IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
Pull networking fixes from David Miller:
1) Restore previous behavior of CAP_SYS_ADMIN wrt loading networking
BPF programs, from Maciej Żenczykowski.
2) Fix dropped broadcasts in mac80211 code, from Seevalamuthu
Mariappan.
3) Slay memory leak in nl80211 bss color attribute parsing code, from
Luca Coelho.
4) Get route from skb properly in ip_route_use_hint(), from Miaohe Lin.
5) Don't allow anything other than ARPHRD_ETHER in llc code, from Eric
Dumazet.
6) xsk code dips too deeply into DMA mapping implementation internals.
Add dma_need_sync and use it. From Christoph Hellwig
7) Enforce power-of-2 for BPF ringbuf sizes. From Andrii Nakryiko.
8) Check for disallowed attributes when loading flow dissector BPF
programs. From Lorenz Bauer.
9) Correct packet injection to L3 tunnel devices via AF_PACKET, from
Jason A. Donenfeld.
10) Don't advertise checksum offload on ipa devices that don't support
it. From Alex Elder.
11) Resolve several issues in TCP MD5 signature support. Missing memory
barriers, bogus options emitted when using syncookies, and failure
to allow md5 key changes in established states. All from Eric
Dumazet.
12) Fix interface leak in hsr code, from Taehee Yoo.
13) VF reset fixes in hns3 driver, from Huazhong Tan.
14) Make loopback work again with ipv6 anycast, from David Ahern.
15) Fix TX starvation under high load in fec driver, from Tobias
Waldekranz.
16) MLD2 payload lengths not checked properly in bridge multicast code,
from Linus Lüssing.
17) Packet scheduler code that wants to find the inner protocol
currently only works for one level of VLAN encapsulation. Allow
Q-in-Q situations to work properly here, from Toke
Høiland-Jørgensen.
18) Fix route leak in l2tp, from Xin Long.
19) Resolve conflict between the sk->sk_user_data usage of bpf reuseport
support and various protocols. From Martin KaFai Lau.
20) Fix socket cgroup v2 reference counting in some situations, from
Cong Wang.
21) Cure memory leak in mlx5 connection tracking offload support, from
Eli Britstein.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
mlxsw: pci: Fix use-after-free in case of failed devlink reload
mlxsw: spectrum_router: Remove inappropriate usage of WARN_ON()
net: macb: fix call to pm_runtime in the suspend/resume functions
net: macb: fix macb_suspend() by removing call to netif_carrier_off()
net: macb: fix macb_get/set_wol() when moving to phylink
net: macb: mark device wake capable when "magic-packet" property present
net: macb: fix wakeup test in runtime suspend/resume routines
bnxt_en: fix NULL dereference in case SR-IOV configuration fails
libbpf: Fix libbpf hashmap on (I)LP32 architectures
net/mlx5e: CT: Fix memory leak in cleanup
net/mlx5e: Fix port buffers cell size value
net/mlx5e: Fix 50G per lane indication
net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash
net/mlx5e: Fix VXLAN configuration restore after function reload
net/mlx5e: Fix usage of rcu-protected pointer
net/mxl5e: Verify that rpriv is not NULL
net/mlx5: E-Switch, Fix vlan or qos setting in legacy mode
net/mlx5: Fix eeprom support for SFP module
cgroup: Fix sock_cgroup_data on big-endian.
selftests: bpf: Fix detach from sockmap tests
...
PERF_RECORD_KSYMBOL_TYPE_OOL marks an executable page. Create a map
backed only by memory, which will be populated as necessary by text poke
events.
Committer notes:
From the patch:
OOL stands for "Out of line" code such as kprobe-replaced instructions
or optimized kprobes or ftrace trampolines.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20200512121922.8997-13-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add processing for PERF_RECORD_TEXT_POKE events. When a text poke event
is processed, then the kernel dso data cache is updated with the poked
bytes.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20200512121922.8997-12-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I realize that we fairly recently raised it to 4.8, but the fact is, 4.9
is a much better minimum version to target.
We have a number of workarounds for actual bugs in pre-4.9 gcc versions
(including things like internal compiler errors on ARM), but we also
have some syntactic workarounds for lacking features.
In particular, raising the minimum to 4.9 means that we can now just
assume _Generic() exists, which is likely the much better replacement
for a lot of very convoluted built-time magic with conditionals on
sizeof and/or __builtin_choose_expr() with same_type() etc.
Using _Generic also means that you will need to have a very recent
version of 'sparse', but thats easy to build yourself, and much less of
a hassle than some old gcc version can be.
The latest (in a long string) of reasons for minimum compiler version
upgrades was commit 5435f73d5c4a ("efi/x86: Fix build with gcc 4").
Ard points out that RHEL 7 uses gcc-4.8, but the people who stay back on
old RHEL versions persumably also don't build their own kernels anyway.
And maybe they should cross-built or just have a little side affair with
a newer compiler?
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add auto-detection for the cgroup/sock_release programs.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200706230128.4073544-3-sdf@google.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-07-04
The following pull-request contains BPF updates for your *net-next* tree.
We've added 73 non-merge commits during the last 17 day(s) which contain
a total of 106 files changed, 5233 insertions(+), 1283 deletions(-).
The main changes are:
1) bpftool ability to show PIDs of processes having open file descriptors
for BPF map/program/link/BTF objects, relying on BPF iterator progs
to extract this info efficiently, from Andrii Nakryiko.
2) Addition of BPF iterator progs for dumping TCP and UDP sockets to
seq_files, from Yonghong Song.
3) Support access to BPF map fields in struct bpf_map from programs
through BTF struct access, from Andrey Ignatov.
4) Add a bpf_get_task_stack() helper to be able to dump /proc/*/stack
via seq_file from BPF iterator progs, from Song Liu.
5) Make SO_KEEPALIVE and related options available to bpf_setsockopt()
helper, from Dmitry Yakunin.
6) Optimize BPF sk_storage selection of its caching index, from Martin
KaFai Lau.
7) Removal of redundant synchronize_rcu()s from BPF map destruction which
has been a historic leftover, from Alexei Starovoitov.
8) Several improvements to test_progs to make it easier to create a shell
loop that invokes each test individually which is useful for some CIs,
from Jesper Dangaard Brouer.
9) Fix bpftool prog dump segfault when compiled without skeleton code on
older clang versions, from John Fastabend.
10) Bunch of cleanups and minor improvements, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce helper bpf_get_task_stack(), which dumps stack trace of given
task. This is different to bpf_get_stack(), which gets stack track of
current task. One potential use case of bpf_get_task_stack() is to call
it from bpf_iter__task and dump all /proc/<pid>/stack to a seq_file.
bpf_get_task_stack() uses stack_trace_save_tsk() instead of
get_perf_callchain() for kernel stack. The benefit of this choice is that
stack_trace_save_tsk() doesn't require changes in arch/. The downside of
using stack_trace_save_tsk() is that stack_trace_save_tsk() dumps the
stack trace to unsigned long array. For 32-bit systems, we need to
translate it to u64 array.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630062846.664389-3-songliubraving@fb.com
Daniel Borkmann says:
====================
pull-request: bpf 2020-06-30
The following pull-request contains BPF updates for your *net* tree.
We've added 28 non-merge commits during the last 9 day(s) which contain
a total of 35 files changed, 486 insertions(+), 232 deletions(-).
The main changes are:
1) Fix an incorrect verifier branch elimination for PTR_TO_BTF_ID pointer
types, from Yonghong Song.
2) Fix UAPI for sockmap and flow_dissector progs that were ignoring various
arguments passed to BPF_PROG_{ATTACH,DETACH}, from Lorenz Bauer & Jakub Sitnicki.
3) Fix broken AF_XDP DMA hacks that are poking into dma-direct and swiotlb
internals and integrate it properly into DMA core, from Christoph Hellwig.
4) Fix RCU splat from recent changes to avoid skipping ingress policy when
kTLS is enabled, from John Fastabend.
5) Fix BPF ringbuf map to enforce size to be the power of 2 in order for its
position masking to work, from Andrii Nakryiko.
6) Fix regression from CAP_BPF work to re-allow CAP_SYS_ADMIN for loading
of network programs, from Maciej Żenczykowski.
7) Fix libbpf section name prefix for devmap progs, from Jesper Dangaard Brouer.
8) Fix formatting in UAPI documentation for BPF helpers, from Quentin Monnet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Don't insert ESP trailer twice in IPSEC code, from Huy Nguyen.
2) The default crypto algorithm selection in Kconfig for IPSEC is out
of touch with modern reality, fix this up. From Eric Biggers.
3) bpftool is missing an entry for BPF_MAP_TYPE_RINGBUF, from Andrii
Nakryiko.
4) Missing init of ->frame_sz in xdp_convert_zc_to_xdp_frame(), from
Hangbin Liu.
5) Adjust packet alignment handling in ax88179_178a driver to match
what the hardware actually does. From Jeremy Kerr.
6) register_netdevice can leak in the case one of the notifiers fail,
from Yang Yingliang.
7) Use after free in ip_tunnel_lookup(), from Taehee Yoo.
8) VLAN checks in sja1105 DSA driver need adjustments, from Vladimir
Oltean.
9) tg3 driver can sleep forever when we get enough EEH errors, fix from
David Christensen.
10) Missing {READ,WRITE}_ONCE() annotations in various Intel ethernet
drivers, from Ciara Loftus.
11) Fix scanning loop break condition in of_mdiobus_register(), from
Florian Fainelli.
12) MTU limit is incorrect in ibmveth driver, from Thomas Falcon.
13) Endianness fix in mlxsw, from Ido Schimmel.
14) Use after free in smsc95xx usbnet driver, from Tuomas Tynkkynen.
15) Missing bridge mrp configuration validation, from Horatiu Vultur.
16) Fix circular netns references in wireguard, from Jason A. Donenfeld.
17) PTP initialization on recovery is not done properly in qed driver,
from Alexander Lobakin.
18) Endian conversion of L4 ports in filters of cxgb4 driver is wrong,
from Rahul Lakkireddy.
19) Don't clear bound device TX queue of socket prematurely otherwise we
get problems with ktls hw offloading, from Tariq Toukan.
20) ipset can do atomics on unaligned memory, fix from Russell King.
21) Align ethernet addresses properly in bridging code, from Thomas
Martitz.
22) Don't advertise ipv4 addresses on SCTP sockets having ipv6only set,
from Marcelo Ricardo Leitner.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (149 commits)
rds: transport module should be auto loaded when transport is set
sch_cake: fix a few style nits
sch_cake: don't call diffserv parsing code when it is not needed
sch_cake: don't try to reallocate or unshare skb unconditionally
ethtool: fix error handling in linkstate_prepare_data()
wil6210: account for napi_gro_receive never returning GRO_DROP
hns: do not cast return value of napi_gro_receive to null
socionext: account for napi_gro_receive never returning GRO_DROP
wireguard: receive: account for napi_gro_receive never returning GRO_DROP
vxlan: fix last fdb index during dump of fdb with nhid
sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket
tc-testing: avoid action cookies with odd length.
bpf: tcp: bpf_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
net: dsa: sja1105: fix tc-gate schedule with single element
net: dsa: sja1105: recalculate gating subschedule after deleting tc-gate rules
net: dsa: sja1105: unconditionally free old gating config
net: dsa: sja1105: move sja1105_compose_gating_subschedule at the top
net: macb: free resources on failure path of at91ether_open()
net: macb: call pm_runtime_put_sync on failure path
...
The helper is used in tracing programs to cast a socket
pointer to a udp6_sock pointer.
The return value could be NULL if the casting is illegal.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20200623230815.3988481-1-yhs@fb.com
Three more helpers are added to cast a sock_common pointer to
an tcp_sock, tcp_timewait_sock or a tcp_request_sock for
tracing programs.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230811.3988277-1-yhs@fb.com
The helper is used in tracing programs to cast a socket
pointer to a tcp6_sock pointer.
The return value could be NULL if the casting is illegal.
A new helper return type RET_PTR_TO_BTF_ID_OR_NULL is added
so the verifier is able to deduce proper return types for the helper.
Different from the previous BTF_ID based helpers,
the bpf_skc_to_tcp6_sock() argument can be several possible
btf_ids. More specifically, all possible socket data structures
with sock_common appearing in the first in the memory layout.
This patch only added socket types related to tcp and udp.
All possible argument btf_id and return value btf_id
for helper bpf_skc_to_tcp6_sock() are pre-calculcated and
cached. In the future, it is even possible to precompute
these btf_id's at kernel build time.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230809.3988195-1-yhs@fb.com
This patch adds support of SO_KEEPALIVE flag and TCP related options
to bpf_setsockopt() routine. This is helpful if we want to enable or tune
TCP keepalive for applications which don't do it in the userspace code.
v3:
- update kernel-doc in uapi (Nikita Vetoshkin <nekto0n@yandex-team.ru>)
v4:
- update kernel-doc in tools too (Alexei Starovoitov)
- add test to selftests (Alexei Starovoitov)
Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200620153052.9439-3-zeil@yandex-team.ru
When producing the bpf-helpers.7 man page from the documentation from
the BPF user space header file, rst2man complains:
<stdin>:2636: (ERROR/3) Unexpected indentation.
<stdin>:2640: (WARNING/2) Block quote ends without a blank line; unexpected unindent.
Let's fix formatting for the relevant chunk (item list in
bpf_ringbuf_query()'s description), and for a couple other functions.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200623153935.6215-1-quentin@isovalent.com
Switch most of BPF helper definitions from returning int to long. These
definitions are coming from comments in BPF UAPI header and are used to
generate bpf_helper_defs.h (under libbpf) to be later included and used from
BPF programs.
In actual in-kernel implementation, all the helpers are defined as returning
u64, but due to some historical reasons, most of them are actually defined as
returning int in UAPI (usually, to return 0 on success, and negative value on
error).
This actually causes Clang to quite often generate sub-optimal code, because
compiler believes that return value is 32-bit, and in a lot of cases has to be
up-converted (usually with a pair of 32-bit bit shifts) to 64-bit values,
before they can be used further in BPF code.
Besides just "polluting" the code, these 32-bit shifts quite often cause
problems for cases in which return value matters. This is especially the case
for the family of bpf_probe_read_str() functions. There are few other similar
helpers (e.g., bpf_read_branch_records()), in which return value is used by
BPF program logic to record variable-length data and process it. For such
cases, BPF program logic carefully manages offsets within some array or map to
read variable-length data. For such uses, it's crucial for BPF verifier to
track possible range of register values to prove that all the accesses happen
within given memory bounds. Those extraneous zero-extending bit shifts,
inserted by Clang (and quite often interleaved with other code, which makes
the issues even more challenging and sometimes requires employing extra
per-variable compiler barriers), throws off verifier logic and makes it mark
registers as having unknown variable offset. We'll study this pattern a bit
later below.
Another common pattern is to check return of BPF helper for non-zero state to
detect error conditions and attempt alternative actions in such case. Even in
this simple and straightforward case, this 32-bit vs BPF's native 64-bit mode
quite often leads to sub-optimal and unnecessary extra code. We'll look at
this pattern as well.
Clang's BPF target supports two modes of code generation: ALU32, in which it
is capable of using lower 32-bit parts of registers, and no-ALU32, in which
only full 64-bit registers are being used. ALU32 mode somewhat mitigates the
above described problems, but not in all cases.
This patch switches all the cases in which BPF helpers return 0 or negative
error from returning int to returning long. It is shown below that such change
in definition leads to equivalent or better code. No-ALU32 mode benefits more,
but ALU32 mode doesn't degrade or still gets improved code generation.
Another class of cases switched from int to long are bpf_probe_read_str()-like
helpers, which encode successful case as non-negative values, while still
returning negative value for errors.
In all of such cases, correctness is preserved due to two's complement
encoding of negative values and the fact that all helpers return values with
32-bit absolute value. Two's complement ensures that for negative values
higher 32 bits are all ones and when truncated, leave valid negative 32-bit
value with the same value. Non-negative values have upper 32 bits set to zero
and similarly preserve value when high 32 bits are truncated. This means that
just casting to int/u32 is correct and efficient (and in ALU32 mode doesn't
require any extra shifts).
To minimize the chances of regressions, two code patterns were investigated,
as mentioned above. For both patterns, BPF assembly was analyzed in
ALU32/NO-ALU32 compiler modes, both with current 32-bit int return type and
new 64-bit long return type.
Case 1. Variable-length data reading and concatenation. This is quite
ubiquitous pattern in tracing/monitoring applications, reading data like
process's environment variables, file path, etc. In such case, many pieces of
string-like variable-length data are read into a single big buffer, and at the
end of the process, only a part of array containing actual data is sent to
user-space for further processing. This case is tested in test_varlen.c
selftest (in the next patch). Code flow is roughly as follows:
void *payload = &sample->payload;
u64 len;
len = bpf_probe_read_kernel_str(payload, MAX_SZ1, &source_data1);
if (len <= MAX_SZ1) {
payload += len;
sample->len1 = len;
}
len = bpf_probe_read_kernel_str(payload, MAX_SZ2, &source_data2);
if (len <= MAX_SZ2) {
payload += len;
sample->len2 = len;
}
/* and so on */
sample->total_len = payload - &sample->payload;
/* send over, e.g., perf buffer */
There could be two variations with slightly different code generated: when len
is 64-bit integer and when it is 32-bit integer. Both variations were analysed.
BPF assembly instructions between two successive invocations of
bpf_probe_read_kernel_str() were used to check code regressions. Results are
below, followed by short analysis. Left side is using helpers with int return
type, the right one is after the switch to long.
ALU32 + INT ALU32 + LONG
=========== ============
64-BIT (13 insns): 64-BIT (10 insns):
------------------------------------ ------------------------------------
17: call 115 17: call 115
18: if w0 > 256 goto +9 <LBB0_4> 18: if r0 > 256 goto +6 <LBB0_4>
19: w1 = w0 19: r1 = 0 ll
20: r1 <<= 32 21: *(u64 *)(r1 + 0) = r0
21: r1 s>>= 32 22: r6 = 0 ll
22: r2 = 0 ll 24: r6 += r0
24: *(u64 *)(r2 + 0) = r1 00000000000000c8 <LBB0_4>:
25: r6 = 0 ll 25: r1 = r6
27: r6 += r1 26: w2 = 256
00000000000000e0 <LBB0_4>: 27: r3 = 0 ll
28: r1 = r6 29: call 115
29: w2 = 256
30: r3 = 0 ll
32: call 115
32-BIT (11 insns): 32-BIT (12 insns):
------------------------------------ ------------------------------------
17: call 115 17: call 115
18: if w0 > 256 goto +7 <LBB1_4> 18: if w0 > 256 goto +8 <LBB1_4>
19: r1 = 0 ll 19: r1 = 0 ll
21: *(u32 *)(r1 + 0) = r0 21: *(u32 *)(r1 + 0) = r0
22: w1 = w0 22: r0 <<= 32
23: r6 = 0 ll 23: r0 >>= 32
25: r6 += r1 24: r6 = 0 ll
00000000000000d0 <LBB1_4>: 26: r6 += r0
26: r1 = r6 00000000000000d8 <LBB1_4>:
27: w2 = 256 27: r1 = r6
28: r3 = 0 ll 28: w2 = 256
30: call 115 29: r3 = 0 ll
31: call 115
In ALU32 mode, the variant using 64-bit length variable clearly wins and
avoids unnecessary zero-extension bit shifts. In practice, this is even more
important and good, because BPF code won't need to do extra checks to "prove"
that payload/len are within good bounds.
32-bit len is one instruction longer. Clang decided to do 64-to-32 casting
with two bit shifts, instead of equivalent `w1 = w0` assignment. The former
uses extra register. The latter might potentially lose some range information,
but not for 32-bit value. So in this case, verifier infers that r0 is [0, 256]
after check at 18:, and shifting 32 bits left/right keeps that range intact.
We should probably look into Clang's logic and see why it chooses bitshifts
over sub-register assignments for this.
NO-ALU32 + INT NO-ALU32 + LONG
============== ===============
64-BIT (14 insns): 64-BIT (10 insns):
------------------------------------ ------------------------------------
17: call 115 17: call 115
18: r0 <<= 32 18: if r0 > 256 goto +6 <LBB0_4>
19: r1 = r0 19: r1 = 0 ll
20: r1 >>= 32 21: *(u64 *)(r1 + 0) = r0
21: if r1 > 256 goto +7 <LBB0_4> 22: r6 = 0 ll
22: r0 s>>= 32 24: r6 += r0
23: r1 = 0 ll 00000000000000c8 <LBB0_4>:
25: *(u64 *)(r1 + 0) = r0 25: r1 = r6
26: r6 = 0 ll 26: r2 = 256
28: r6 += r0 27: r3 = 0 ll
00000000000000e8 <LBB0_4>: 29: call 115
29: r1 = r6
30: r2 = 256
31: r3 = 0 ll
33: call 115
32-BIT (13 insns): 32-BIT (13 insns):
------------------------------------ ------------------------------------
17: call 115 17: call 115
18: r1 = r0 18: r1 = r0
19: r1 <<= 32 19: r1 <<= 32
20: r1 >>= 32 20: r1 >>= 32
21: if r1 > 256 goto +6 <LBB1_4> 21: if r1 > 256 goto +6 <LBB1_4>
22: r2 = 0 ll 22: r2 = 0 ll
24: *(u32 *)(r2 + 0) = r0 24: *(u32 *)(r2 + 0) = r0
25: r6 = 0 ll 25: r6 = 0 ll
27: r6 += r1 27: r6 += r1
00000000000000e0 <LBB1_4>: 00000000000000e0 <LBB1_4>:
28: r1 = r6 28: r1 = r6
29: r2 = 256 29: r2 = 256
30: r3 = 0 ll 30: r3 = 0 ll
32: call 115 32: call 115
In NO-ALU32 mode, for the case of 64-bit len variable, Clang generates much
superior code, as expected, eliminating unnecessary bit shifts. For 32-bit
len, code is identical.
So overall, only ALU-32 32-bit len case is more-or-less equivalent and the
difference stems from internal Clang decision, rather than compiler lacking
enough information about types.
Case 2. Let's look at the simpler case of checking return result of BPF helper
for errors. The code is very simple:
long bla;
if (bpf_probe_read_kenerl(&bla, sizeof(bla), 0))
return 1;
else
return 0;
ALU32 + CHECK (9 insns) ALU32 + CHECK (9 insns)
==================================== ====================================
0: r1 = r10 0: r1 = r10
1: r1 += -8 1: r1 += -8
2: w2 = 8 2: w2 = 8
3: r3 = 0 3: r3 = 0
4: call 113 4: call 113
5: w1 = w0 5: r1 = r0
6: w0 = 1 6: w0 = 1
7: if w1 != 0 goto +1 <LBB2_2> 7: if r1 != 0 goto +1 <LBB2_2>
8: w0 = 0 8: w0 = 0
0000000000000048 <LBB2_2>: 0000000000000048 <LBB2_2>:
9: exit 9: exit
Almost identical code, the only difference is the use of full register
assignment (r1 = r0) vs half-registers (w1 = w0) in instruction #5. On 32-bit
architectures, new BPF assembly might be slightly less optimal, in theory. But
one can argue that's not a big issue, given that use of full registers is
still prevalent (e.g., for parameter passing).
NO-ALU32 + CHECK (11 insns) NO-ALU32 + CHECK (9 insns)
==================================== ====================================
0: r1 = r10 0: r1 = r10
1: r1 += -8 1: r1 += -8
2: r2 = 8 2: r2 = 8
3: r3 = 0 3: r3 = 0
4: call 113 4: call 113
5: r1 = r0 5: r1 = r0
6: r1 <<= 32 6: r0 = 1
7: r1 >>= 32 7: if r1 != 0 goto +1 <LBB2_2>
8: r0 = 1 8: r0 = 0
9: if r1 != 0 goto +1 <LBB2_2> 0000000000000048 <LBB2_2>:
10: r0 = 0 9: exit
0000000000000058 <LBB2_2>:
11: exit
NO-ALU32 is a clear improvement, getting rid of unnecessary zero-extension bit
shifts.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200623032224.4020118-1-andriin@fb.com
To pick the changes from:
b383a73f2b83 ("fs/ext4: Introduce DAX inode flag")
And silence this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h
It causes various beautifiers for things like fspick, fsmount, etc (see
below) to get rebuilt, but this specific change doesn't make 'perf
trace' be capable of decoding anything new, as we still don't decode
what comes from ioctls, just its cmds.
Details about the update:
$ cp include/uapi/linux/fs.h tools/include/uapi/linux/fs.h
$ git diff
diff --git a/tools/include/uapi/linux/fs.h b/tools/include/uapi/linux/fs.h
index 379a612f8f1d..f44eb0a04afd 100644
--- a/tools/include/uapi/linux/fs.h
+++ b/tools/include/uapi/linux/fs.h
@@ -262,6 +262,7 @@ struct fsxattr {
#define FS_EA_INODE_FL 0x00200000 /* Inode used for large EA */
#define FS_EOFBLOCKS_FL 0x00400000 /* Reserved for ext4 */
#define FS_NOCOW_FL 0x00800000 /* Do not cow file */
+#define FS_DAX_FL 0x02000000 /* Inode is DAX */
#define FS_INLINE_DATA_FL 0x10000000 /* Reserved for ext4 */
#define FS_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
#define FS_CASEFOLD_FL 0x40000000 /* Folder is case insensitive */
$ m
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build
INSTALL GTK UI
CC /tmp/build/perf/builtin-trace.o
DESCEND plugins
CC /tmp/build/perf/trace/beauty/fsmount.o
CC /tmp/build/perf/trace/beauty/fspick.o
CC /tmp/build/perf/trace/beauty/mount_flags.o
CC /tmp/build/perf/trace/beauty/move_mount.o
CC /tmp/build/perf/trace/beauty/renameat.o
CC /tmp/build/perf/trace/beauty/sync_file_range.o
INSTALL trace_plugins
LD /tmp/build/perf/trace/beauty/perf-in.o
LD /tmp/build/perf/perf-in.o
LINK /tmp/build/perf/perf
<SNIP>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get some newer headers that got out of sync with the copies in tools/
so that we can try to have the tools/perf/ build clean for v5.8 with
fewer pull requests.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix definition of bpf_ringbuf_output() in UAPI header comments, which is used
to generate libbpf's bpf_helper_defs.h header. Return value is a number (error
code), not a pointer.
Fixes: 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200615214926.3638836-1-andriin@fb.com
Pull networking fixes from David Miller:
1) Fix cfg80211 deadlock, from Johannes Berg.
2) RXRPC fails to send norigications, from David Howells.
3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from
Geliang Tang.
4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu.
5) The ucc_geth driver needs __netdev_watchdog_up exported, from
Valentin Longchamp.
6) Fix hashtable memory leak in dccp, from Wang Hai.
7) Fix how nexthops are marked as FDB nexthops, from David Ahern.
8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni.
9) Fix crashes in tipc_disc_rcv(), from Tuong Lien.
10) Fix link speed reporting in iavf driver, from Brett Creeley.
11) When a channel is used for XSK and then reused again later for XSK,
we forget to clear out the relevant data structures in mlx5 which
causes all kinds of problems. Fix from Maxim Mikityanskiy.
12) Fix memory leak in genetlink, from Cong Wang.
13) Disallow sockmap attachments to UDP sockets, it simply won't work.
From Lorenz Bauer.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits)
net: ethernet: ti: ale: fix allmulti for nu type ale
net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init
net: atm: Remove the error message according to the atomic context
bpf: Undo internal BPF_PROBE_MEM in BPF insns dump
libbpf: Support pre-initializing .bss global variables
tools/bpftool: Fix skeleton codegen
bpf: Fix memlock accounting for sock_hash
bpf: sockmap: Don't attach programs to UDP sockets
bpf: tcp: Recv() should return 0 when the peer socket is closed
ibmvnic: Flush existing work items before device removal
genetlink: clean up family attributes allocations
net: ipa: header pad field only valid for AP->modem endpoint
net: ipa: program upper nibbles of sequencer type
net: ipa: fix modem LAN RX endpoint id
net: ipa: program metadata mask differently
ionic: add pcie_print_link_status
rxrpc: Fix race between incoming ACK parser and retransmitter
net/mlx5: E-Switch, Fix some error pointer dereferences
net/mlx5: Don't fail driver on failure to create debugfs
net/mlx5e: CT: Fix ipv6 nat header rewrite actions
...
Alexei Starovoitov says:
====================
pull-request: bpf 2020-06-12
The following pull-request contains BPF updates for your *net* tree.
We've added 26 non-merge commits during the last 10 day(s) which contain
a total of 27 files changed, 348 insertions(+), 93 deletions(-).
The main changes are:
1) sock_hash accounting fix, from Andrey.
2) libbpf fix and probe_mem sanitizing, from Andrii.
3) sock_hash fixes, from Jakub.
4) devmap_val fix, from Jesper.
5) load_bytes_relative fix, from YiFei.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch series "Add log level to show_stack()", v3.
Add log level argument to show_stack().
Done in three stages:
1. Introducing show_stack_loglvl() for every architecture
2. Migrating old users with an explicit log level
3. Renaming show_stack_loglvl() into show_stack()
Justification:
- It's a design mistake to move a business-logic decision into platform
realization detail.
- I have currently two patches sets that would benefit from this work:
Removing console_loglevel jumps in sysrq driver [1] Hung task warning
before panic [2] - suggested by Tetsuo (but he probably didn't realise
what it would involve).
- While doing (1), (2) the backtraces were adjusted to headers and other
messages for each situation - so there won't be a situation when the
backtrace is printed, but the headers are missing because they have
lesser log level (or the reverse).
- As the result in (2) plays with console_loglevel for kdb are removed.
The least important for upstream, but maybe still worth to note that every
company I've worked in so far had an off-list patch to print backtrace
with the needed log level (but only for the architecture they cared
about). If you have other ideas how you will benefit from show_stack()
with a log level - please, reply to this cover letter.
See also discussion on v1:
https://lore.kernel.org/linux-riscv/20191106083538.z5nlpuf64cigxigh@pathway.suse.cz/
This patch (of 50):
print_ip_sym() needs to have a log level parameter to comply with other
parts being printed. Otherwise, half of the expected backtrace would be
printed and other may be missing with some logging level.
The following callee(s) are using now the adjusted log level:
- microblaze/unwind: the same level as headers & userspace unwind.
Note that pr_debug()'s there are for debugging the unwinder itself.
- nds32/traps: symbol addresses are printed with the same log level
as backtrace headers.
- lockdep: ip for locking issues is printed with the same log level
as other part of the warning.
- sched: ip where preemption was disabled is printed as error like
the rest part of the message.
- ftrace: bug reports are now consistent in the log level being used.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Will Deacon <will@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-2-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To pick the changes in:
f97f5a56f597 ("x86/kvm/hyper-v: Add support for synthetic debugger interface")
850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration")
2c4c41325540 ("KVM: x86: Print symbolic names of VMX VM-Exit flags in traces")
cc440cdad5b7 ("KVM: nSVM: implement KVM_GET_NESTED_STATE and KVM_SET_NESTED_STATE")
f7d31e65368a ("x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit")
72de5fa4c161 ("KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT")
acd05785e48c ("kvm: add capability for halt polling")
3ecad8c2c1ff ("docs: fix broken references for ReST files that moved around")
That do not result in any change in tooling, as the additions are not
being used in any table generator.
This silences these perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/kvm.h' differs from latest version at 'arch/x86/include/uapi/asm/kvm.h'
diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/vmx.h' differs from latest version at 'arch/x86/include/uapi/asm/vmx.h'
diff -u tools/arch/x86/include/uapi/asm/vmx.h arch/x86/include/uapi/asm/vmx.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Matlack <dmatlack@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jon Doron <arilou@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Shier <pshier@google.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the change in:
4ef10fe05ba0 ("drm/i915/perf: add new open param to configure polling of OA buffer")
11ecbdddf2f8 ("drm/i915/perf: introduce global sseu pinning")
That don't result in any changes in tooling, just silences this perf
build warning:
Warning: Kernel ABI header at 'tools/include/uapi/drm/i915_drm.h' differs from latest version at 'include/uapi/drm/i915_drm.h'
diff -u tools/include/uapi/drm/i915_drm.h include/uapi/drm/i915_drm.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes from:
e3b1078bedd3 ("fscrypt: add support for IV_INO_LBLK_32 policies")
That don't trigger any changes in tooling.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/fscrypt.h' differs from latest version at 'include/uapi/linux/fscrypt.h'
diff -u tools/include/uapi/linux/fscrypt.h include/uapi/linux/fscrypt.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes from:
80340fe3605c ("statx: add mount_root")
fa2fcf4f1df1 ("statx: add mount ID")
581701b7efd6 ("uapi: deprecate STATX_ALL")
712b2698e4c0 ("fs/stat: Define DAX statx attribute")
These add some constants that will have to be manually added in a
followup cset, at some point this should move to the shell based
automated way.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/stat.h' differs from latest version at 'include/uapi/linux/stat.h'
diff -u tools/include/uapi/linux/stat.h include/uapi/linux/stat.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Update the copies of files affected by:
c8ffd8bcdd28 ("vfs: add faccessat2 syscall")
To address this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/fcntl.h' differs from latest version at 'include/uapi/linux/fcntl.h'
diff -u tools/include/uapi/linux/fcntl.h include/uapi/linux/fcntl.h
Warning: Kernel ABI header at 'tools/include/uapi/asm-generic/unistd.h' differs from latest version at 'include/uapi/asm-generic/unistd.h'
diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h
Warning: Kernel ABI header at 'tools/perf/arch/x86/entry/syscalls/syscall_64.tbl' differs from latest version at 'arch/x86/entry/syscalls/syscall_64.tbl'
diff -u tools/perf/arch/x86/entry/syscalls/syscall_64.tbl arch/x86/entry/syscalls/syscall_64.tbl
Which results in 'perf trace' gaining support for the 'faccessat2'
syscall, now one can use:
# perf trace -e faccessat2
And have system wide tracing of this syscall. And this also will include
it;
# perf trace -e faccess*
Together with the other variants.
How it affects building/usage (on an x86_64 system):
$ cp /tmp/build/perf/arch/x86/include/generated/asm/syscalls_64.c /tmp/syscalls_64.c.before
$
[root@five ~]# perf trace -e faccessat2
event syntax error: 'faccessat2'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf trace [<options>] [<command>]
or: perf trace [<options>] -- <command> [<options>]
or: perf trace record [<options>] [<command>]
or: perf trace record [<options>] -- <command> [<options>]
-e, --event <event> event/syscall selector. use 'perf list' to list available events
[root@five ~]#
$ cp arch/x86/entry/syscalls/syscall_64.tbl tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
$ git diff
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index 37b844f839bc..78847b32e137 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -359,6 +359,7 @@
435 common clone3 sys_clone3
437 common openat2 sys_openat2
438 common pidfd_getfd sys_pidfd_getfd
+439 common faccessat2 sys_faccessat2
#
# x32-specific system call numbers start at 512 to avoid cache impact
$
$ make -C tools/perf O=/tmp/build/perf/ install-bin
<SNIP>
CC /tmp/build/perf/util/syscalltbl.o
LD /tmp/build/perf/util/perf-in.o
LD /tmp/build/perf/perf-in.o
LINK /tmp/build/perf/perf
<SNIP>
[root@five ~]# perf trace -e faccessat2
^C[root@five ~]#
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- Further Intel PT call-trace fixes
- Improve SELinux docs and tool warnings
- Fix race at exit in 'perf record' using eventfd.
- Add missing build tests to the default set of 'make -C tools/perf build-test'
- Sync msr-index.h getting new AMD MSRs to decode and filter in 'perf trace'.
- Fix fallback to libaudit in 'perf trace' for arches not using per-arch *.tbl files.
- Fixes for 'perf ftrace'.
- Fixes and improvements for the 'perf stat' metrics.
- Use dummy event to get PERF_RECORD_{FORK,MMAP,etc} while synthesizing
those metadata events for pre-existing threads.
- Fix leaks detected using clang tooling.
- Improvements to PMU event metric testing.
- Report summary for 'perf stat' interval mode at the end, summing up
all the intervals.
- Improve pipe mode, i.e. this now works as expected, continuously
dumping samples:
# perf record -g -e raw_syscalls:sys_enter | perf --no-pager script
- Fixes for event grouping, detecting incompatible groups such as:
# perf stat -e '{cycles,power/energy-cores/}' -v
WARNING: group events cpu maps do not match, disabling group:
anon group { power/energy-cores/, cycles }
power/energy-cores/: 0
cycles: 0-7
- Fixes for 'perf probe': blacklist address checking, number of
kretprobe instances, etc.
- JIT processing improvements and fixes plus the addition of a 'perf
test' entry for the java demangler.
- Add support for synthesizing first/last level cache, TLB and remove
access events from HW tracing in the auxtrace code, first to use is
ARM SPE.
- Vendor events updates and fixes, including for POWER9 and Intel.
- Allow using ~/.perfconfig for removing the ',' separators in 'perf
stat' output.
- Opt-in support for libpfm4.
=================================================================================
Adrian Hunter (8):
perf intel-pt: Use allocated branch stack for PEBS sample
perf symbols: Fix debuginfo search for Ubuntu
perf kcore_copy: Fix module map when there are no modules loaded
perf evlist: Disable 'immediate' events last
perf script: Fix --call-trace for Intel PT
perf record: Respect --no-switch-events
perf intel-pt: Refine kernel decoding only warning message
perf symbols: Fix kernel maps for kcore and eBPF
Alexey Budankov (3):
perf docs: Extend CAP_SYS_ADMIN with CAP_PERFMON where needed
perf tool: Make perf tool aware of SELinux access control
perf docs: Introduce security.txt file to document related issues
Anand K Mistry (1):
perf record: Use an eventfd to wakeup when done
Andi Kleen (1):
perf script: Don't force less for non tty output with --xed
Arnaldo Carvalho de Melo (21):
perf evsel: Rename perf_evsel__object_config() to evsel__object_config()
perf evsel: Rename perf_evsel__resort*() to evsel__resort*()
perf evsel: Rename perf_evsel__fprintf() to evsel__fprintf()
perf evsel: Rename *perf_evsel__get_config_term() & friends to evsel__env()
perf evsel: Rename perf_evsel__new*() to evsel__new*()
perf evsel: Rename perf_evsel__[hs]w_cache* to evsel__[hs]w_cache*
perf counts: Rename perf_evsel__*counts() to evsel__*counts()
perf parse-events: Fix incorrect conversion of 'if () free()' to 'zfree()'
perf evsel: Initialize evsel->per_pkg_mask to NULL in evsel__init()
tools feature: Rename HAVE_EVENTFD to HAVE_EVENTFD_SUPPORT
perf build: Group the NO_SYSCALL_TABLE logic
perf build: Allow explicitely disabling the NO_SYSCALL_TABLE variable
perf trace: Remove union from syscalltbl, all the fields are needed
perf trace: Use zalloc() to make sure all fields are zeroed in the syscalltbl constructor
perf trace: Grow the syscall table as needed when using libaudit
perf build: Remove libaudit from the default feature checks
perf build: Add NO_SYSCALL_TABLE=1 to the build tests
perf build: Add NO_LIBCRYPTO=1 to the default set of build tests
perf build: Add NO_SDT=1 to the default set of build tests
perf build: Add a LIBPFM4=1 build test entry
tools arch x86: Sync the msr-index.h copy with the kernel sources
Changbin Du (2):
perf ftrace: Trace system wide if no target is given
perf ftrace: Detect workload failure
Ed Maste (1):
perf tools: Correct license on jsmn JSON parser
Gustavo A. R. Silva (2):
perf tools: Replace zero-length array with flexible-array
perf branch: Replace zero-length array with flexible-array
Ian Rogers (38):
perf expr: Allow for unlimited escaped characters in a symbol
perf metrics: Fix parse errors in cascade lake metrics
perf metrics: Fix parse errors in skylake metrics
perf expr: Allow ',' to be an other token
perf expr: Increase max other
perf expr: Parse numbers as doubles
perf expr: Debug lex if debugging yacc
perf metrics: Fix parse errors in power8 metrics
perf metrics: Fix parse errors in power9 metrics
perf expr: Print a debug message for division by zero
perf evsel: Dummy events never triggers, no need to ask for PERF_SAMPLE_BRANCH_STACK
perf record: Add dummy event during system wide synthesis
perf c2c: Fix 'perf c2c record -e list' to show the default events used
perf evsel: Fix 2 memory leaks
perf expr: Test parsing of floating point numbers
perf expr: Fix memory leaks in metric bison
perf parse-events: Make add PMU verbose output clearer
perf test: Provide a subtest callback to ask for the reason for skipping a subtest
perf test: Improve pmu event metric testing
perf trace: Fix the selection for architectures to generate the errno name tables
perf beauty: Allow the CC used in the arch errno names script to acccept CFLAGS
perf tools: Grab a copy of libbpf's hashmap
perf expr: Migrate expr ids table to a hashmap
perf metricgroup: Make 'evlist_used' variable a bitmap instead of array of bools
perf expr: Allow numbers to be followed by a dot
perf metricgroup: Free metric_events on error
perf metricgroup: Always place duration_time last
perf metricgroup: Use early return in add_metric
perf metricgroup: Delay events string creation
perf metricgroup: Order event groups by size
perf metricgroup: Remove duped metric group events
perf metricgroup: Add options to not group or merge
perf metricgroup: Remove unnecessary ',' from events
perf list: Add metrics to command line usage
tools compiler.h: Add attribute to disable tail calls
perf tests: Don't tail call optimize in unwind test
perf test: Initialize memory in dwarf-unwind
perf libdw: Fix off-by 1 relative directory includes
Jin Yao (6):
perf parse-events: Use strcmp() to compare the PMU name
perf stat: Fix wrong per-thread runtime stat for interval mode
perf counts: Reset prev_raw_counts counts
perf stat: Copy counts from prev_raw_counts to evsel->counts
perf stat: Save aggr value to first member of prev_raw_counts
perf stat: Report summary for interval mode
Jiri Olsa (13):
perf tools: Do not display extra info when there is nothing to build
perf tools: Do not seek in pipe fd during tracing data processing
perf session: Try to read pipe data from file
perf callchain: Setup callchain properly in pipe mode
perf script: Enable IP fields for callchains
perf tools: Fix is_bpf_image function logic
perf trace: Fix compilation error for make NO_LIBBPF=1 DEBUG=1
perf stat: Fix duration_time value for higher intervals
perf stat: Fail on extra comma while parsing events
perf tests: Consider subtests when searching for user specified tests
perf stat: Do not pass avg to generic_metric
perf parse: Add 'struct parse_events_state' pointer to scanner
perf stat: Ensure group is defined on top of the same cpu mask
Li Bin (1):
perf util: Fix potential SEGFAULT in put_tracepoints_path error path
Masami Hiramatsu (4):
perf probe: Accept the instance number of kretprobe event
perf probe: Fix to check blacklist address correctly
perf probe: Check address correctness by map instead of _etext
perf probe: Do not show the skipped events
Nick Gasson (6):
perf jvmti: Fix jitdump for methods without debug info
perf jvmti: Do not report error when missing debug information
perf tests: Add test for the java demangler
perf jvmti: Fix demangling Java symbols
perf jvmti: Remove redundant jitdump line table entries
perf jit: Fix inaccurate DWARF line table
Paul A. Clarke (5):
perf stat: Increase perf metric output resolution
perf vendor events power9: Add missing metrics to POWER9 'cpi_breakdown'
perf stat: POWER9 metrics: expand "ICT" acronym
perf script: Better align register values in dump
perf config: Add stat.big-num support
Ravi Bangoria (1):
perf powerpc: Don't ignore sym-handling.c file
Stephane Eranian (1):
perf tools: Add optional support for libpfm4
Tan Xiaojun (3):
perf tools: Move arm-spe-pkt-decoder.h/c to the new dir
perf auxtrace: Add four itrace options
perf arm-spe: Support synthetic events
Tiezhu Yang (1):
perf tools: Remove some duplicated includes
Wang ShaoBo (1):
perf bpf-loader: Add missing '*' for key_scan_pos
Xie XiuQi (1):
perf util: Fix memory leak of prefix_if_not_in
=================================================================================
Test results:
The first ones are container based builds of tools/perf with and without libelf
support. Where clang is available, it is also used to build perf with/without
libelf, and building with LIBCLANGLLVM=1 (built-in clang) with gcc and clang
when clang and its devel libraries are installed.
The objtool and samples/bpf/ builds are disabled now that I'm switching from
using the sources in a local volume to fetching them from a http server to
build it inside the container, to make it easier to build in a container cluster.
Those will come back later.
Several are cross builds, the ones with -x-ARCH and the android one, and those
may not have all the features built, due to lack of multi-arch devel packages,
available and being used so far on just a few, like
debian:experimental-x-{arm64,mipsel}.
The 'perf test' one will perform a variety of tests exercising
tools/perf/util/, tools/lib/{bpf,traceevent,etc}, as well as run perf commands
with a variety of command line event specifications to then intercept the
sys_perf_event syscall to check that the perf_event_attr fields are set up as
expected, among a variety of other unit tests.
Then there is the 'make -C tools/perf build-test' ones, that build tools/perf/
with a variety of feature sets, exercising the build with an incomplete set of
features as well as with a complete one. It is planned to have it run on each
of the containers mentioned above, using some container orchestration
infrastructure. Get in contact if interested in helping having this in place.
Ubuntu 19.10 is failing when linking against libllvm, which isn't the default,
needs to be investigated, haven't tested with CC=gcc, but should be the same
problem:
+ make ARCH= CROSS_COMPILE= EXTRA_CFLAGS= LIBCLANGLLVM=1 -C /git/linux/tools/perf O=/tmp/build/perf CC=clang
...
/usr/bin/ld: /usr/lib/llvm-9/lib/libclangAnalysis.a(ExprMutationAnalyzer.cpp.o): in function `clang::ast_matchers::internal::matcher_ignoringImpCasts0Matcher::matches(clang::Expr const&, clang::ast_matchers::internal::ASTMatchFinder*, clang::ast_matchers::internal::BoundNodesTreeBuilder*) const':
(.text._ZNK5clang12ast_matchers8internal32matcher_ignoringImpCasts0Matcher7matchesERKNS_4ExprEPNS1_14ASTMatchFinderEPNS1_21BoundNodesTreeBuilderE[_ZNK5clang12ast_matchers8internal32matcher_ignoringImpCasts0Matcher7matchesERKNS_4ExprEPNS1_14ASTMatchFinderEPNS1_21BoundNodesTreeBuilderE]+0x43): undefined reference to `clang::ast_matchers::internal::DynTypedMatcher::matches(clang::ast_type_traits::DynTypedNode const&, clang::ast_matchers::internal::ASTMatchFinder*, clang::ast_matchers::internal::BoundNodesTreeBuilder*) const'
/usr/bin/ld: /usr/lib/llvm-9/lib/libclangAnalysis.a(ExprMutationAnalyzer.cpp.o): in function `clang::ast_matchers::internal::matcher_hasLoopVariable0Matcher::matches(clang::CXXForRangeStmt const&, clang::ast_matchers::internal::ASTMatchFinder*, clang::ast_matchers::internal::BoundNodesTreeBuilder*) const':
(.text._ZNK5clang12ast_matchers8internal31matcher_hasLoopVariable0Matcher7matchesERKNS_15CXXForRangeStmtEPNS1_14ASTMatchFinderEPNS1_21BoundNodesTreeBuilderE[_ZNK5clang12ast_matchers8internal31matcher_hasLoopVariable0Matcher7matchesERKNS_15CXXForRangeStmtEPNS1_14ASTMatchFinderEPNS1_21BoundNodesTreeBuilderE]+0x48): undefined reference to `clang::ast_matchers::internal::DynTypedMatcher::matches(clang::ast_type_traits::DynTypedNode const&, clang::ast_matchers::internal::ASTMatchFinder*, clang::ast_matchers::internal::BoundNodesTreeBuilder*) const'
...
# export PERF_TARBALL=http://192.168.124.1/perf/perf-5.7.0-rc7.tar.xz
# time dm
1 alpine:3.4 : Ok gcc (Alpine 5.3.0) 5.3.0, clang version 3.8.0 (tags/RELEASE_380/final)
2 alpine:3.5 : Ok gcc (Alpine 6.2.1) 6.2.1 20160822, clang version 3.8.1 (tags/RELEASE_381/final)
3 alpine:3.6 : Ok gcc (Alpine 6.3.0) 6.3.0, clang version 4.0.0 (tags/RELEASE_400/final)
4 alpine:3.7 : Ok gcc (Alpine 6.4.0) 6.4.0, Alpine clang version 5.0.0 (tags/RELEASE_500/final) (based on LLVM 5.0.0)
5 alpine:3.8 : Ok gcc (Alpine 6.4.0) 6.4.0, Alpine clang version 5.0.1 (tags/RELEASE_501/final) (based on LLVM 5.0.1)
6 alpine:3.9 : Ok gcc (Alpine 8.3.0) 8.3.0, Alpine clang version 5.0.1 (tags/RELEASE_502/final) (based on LLVM 5.0.1)
7 alpine:3.10 : Ok gcc (Alpine 8.3.0) 8.3.0, Alpine clang version 8.0.0 (tags/RELEASE_800/final) (based on LLVM 8.0.0)
8 alpine:3.11 : Ok gcc (Alpine 9.2.0) 9.2.0, Alpine clang version 9.0.0 (https://git.alpinelinux.org/aports f7f0d2c2b8bcd6a5843401a9a702029556492689) (based on LLVM 9.0.0)
9 alpine:3.12 : Ok gcc (Alpine 9.3.0) 9.3.0, Alpine clang version 10.0.0 (https://gitlab.alpinelinux.org/alpine/aports.git 7445adce501f8473efdb93b17b5eaf2f1445ed4c)
10 alpine:edge : Ok gcc (Alpine 9.3.0) 9.3.0, Alpine clang version 10.0.0 (git://git.alpinelinux.org/aports 7445adce501f8473efdb93b17b5eaf2f1445ed4c)
11 alt:p8 : Ok x86_64-alt-linux-gcc (GCC) 5.3.1 20151207 (ALT p8 5.3.1-alt3.M80P.1), clang version 3.8.0 (tags/RELEASE_380/final)
12 alt:p9 : Ok x86_64-alt-linux-gcc (GCC) 8.4.1 20200305 (ALT p9 8.4.1-alt0.p9.1), clang version 7.0.1
13 alt:sisyphus : Ok x86_64-alt-linux-gcc (GCC) 9.2.1 20200123 (ALT Sisyphus 9.2.1-alt3), clang version 10.0.0
14 amazonlinux:1 : Ok gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2), clang version 3.6.2 (tags/RELEASE_362/final)
15 amazonlinux:2 : Ok gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-6), clang version 7.0.1 (Amazon Linux 2 7.0.1-1.amzn2.0.2)
16 android-ndk:r12b-arm : Ok arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
17 android-ndk:r15c-arm : Ok arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
18 centos:5 : Ok gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-55)
19 centos:6 : Ok gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-23)
20 centos:7 : Ok gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
21 centos:8 : Ok gcc (GCC) 8.3.1 20190507 (Red Hat 8.3.1-4), clang version 8.0.1 (Red Hat 8.0.1-1.module_el8.1.0+215+a01033fb)
22 clearlinux:latest : Ok gcc (Clear Linux OS for Intel Architecture) 9.3.1 20200501 releases/gcc-9.3.0-196-gcb2c76c8b1, clang version 10.0.0
23 debian:8 : Ok gcc (Debian 4.9.2-10+deb8u2) 4.9.2, Debian clang version 3.5.0-10 (tags/RELEASE_350/final) (based on LLVM 3.5.0)
24 debian:9 : Ok gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, clang version 3.8.1-24 (tags/RELEASE_381/final)
25 debian:10 : Ok gcc (Debian 8.3.0-6) 8.3.0, clang version 7.0.1-8 (tags/RELEASE_701/final)
26 debian:experimental : FAIL gcc (Debian 9.3.0-13) 9.3.0, clang version 9.0.1-12
27 debian:experimental-x-arm64 : Ok aarch64-linux-gnu-gcc (Debian 9.3.0-8) 9.3.0
28 debian:experimental-x-mips : Ok mips-linux-gnu-gcc (Debian 8.3.0-19) 8.3.0
29 debian:experimental-x-mips64 : Ok mips64-linux-gnuabi64-gcc (Debian 9.3.0-8) 9.3.0
30 debian:experimental-x-mipsel : Ok mipsel-linux-gnu-gcc (Debian 9.2.1-8) 9.2.1 20190909
31 fedora:20 : Ok gcc (GCC) 4.8.3 20140911 (Red Hat 4.8.3-7)
32 fedora:22 : Ok gcc (GCC) 5.3.1 20160406 (Red Hat 5.3.1-6), clang version 3.5.0 (tags/RELEASE_350/final)
33 fedora:23 : Ok gcc (GCC) 5.3.1 20160406 (Red Hat 5.3.1-6), clang version 3.7.0 (tags/RELEASE_370/final)
34 fedora:24 : Ok gcc (GCC) 6.3.1 20161221 (Red Hat 6.3.1-1), clang version 3.8.1 (tags/RELEASE_381/final)
35 fedora:24-x-ARC-uClibc : Ok arc-linux-gcc (ARCompact ISA Linux uClibc toolchain 2017.09-rc2) 7.1.1 20170710
36 fedora:25 : Ok gcc (GCC) 6.4.1 20170727 (Red Hat 6.4.1-1), clang version 3.9.1 (tags/RELEASE_391/final)
37 fedora:26 : Ok gcc (GCC) 7.3.1 20180130 (Red Hat 7.3.1-2), clang version 4.0.1 (tags/RELEASE_401/final)
38 fedora:27 : Ok gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-6), clang version 5.0.2 (tags/RELEASE_502/final)
39 fedora:28 : Ok gcc (GCC) 8.3.1 20190223 (Red Hat 8.3.1-2), clang version 6.0.1 (tags/RELEASE_601/final)
40 fedora:29 : Ok gcc (GCC) 8.3.1 20190223 (Red Hat 8.3.1-2), clang version 7.0.1 (Fedora 7.0.1-6.fc29)
41 fedora:30 : Ok gcc (GCC) 9.2.1 20190827 (Red Hat 9.2.1-1), clang version 8.0.0 (Fedora 8.0.0-3.fc30)
42 fedora:30-x-ARC-glibc : Ok arc-linux-gcc (ARC HS GNU/Linux glibc toolchain 2019.03-rc1) 8.3.1 20190225
43 fedora:30-x-ARC-uClibc : Ok arc-linux-gcc (ARCv2 ISA Linux uClibc toolchain 2019.03-rc1) 8.3.1 20190225
44 fedora:31 : Ok gcc (GCC) 9.3.1 20200408 (Red Hat 9.3.1-2), clang version 9.0.1 (Fedora 9.0.1-2.fc31)
45 fedora:32 : Ok gcc (GCC) 10.1.1 20200507 (Red Hat 10.1.1-1), clang version 10.0.0 (Fedora 10.0.0-1.fc32)
46 fedora:rawhide : Ok gcc (GCC) 10.0.1 20200216 (Red Hat 10.0.1-0.8), clang version 10.0.0 (Fedora 10.0.0-0.3.rc2.fc33)
47 gentoo-stage3-amd64:latest : Ok gcc (Gentoo 9.2.0-r2 p3) 9.2.0
48 mageia:5 : Ok gcc (GCC) 4.9.2, clang version 3.5.2 (tags/RELEASE_352/final)
49 mageia:6 : Ok gcc (Mageia 5.5.0-1.mga6) 5.5.0, clang version 3.9.1 (tags/RELEASE_391/final)
50 mageia:7 : Ok gcc (Mageia 8.3.1-0.20190524.1.mga7) 8.3.1 20190524, clang version 8.0.0 (Mageia 8.0.0-1.mga7)
51 manjaro:latest : Ok gcc (GCC) 9.2.0, clang version 9.0.0 (tags/RELEASE_900/final)
52 openmandriva:cooker : Ok gcc (GCC) 10.0.0 20200502 (OpenMandriva), clang version 10.0.1
53 opensuse:15.0 : Ok gcc (SUSE Linux) 7.4.1 20190424 [gcc-7-branch revision 270538], clang version 5.0.1 (tags/RELEASE_501/final 312548)
54 opensuse:15.1 : Ok gcc (SUSE Linux) 7.5.0, clang version 7.0.1 (tags/RELEASE_701/final 349238)
55 opensuse:15.2 : Ok gcc (SUSE Linux) 7.5.0, clang version 7.0.1 (tags/RELEASE_701/final 349238)
56 opensuse:42.3 : Ok gcc (SUSE Linux) 4.8.5, clang version 3.8.0 (tags/RELEASE_380/final 262553)
57 opensuse:tumbleweed : Ok gcc (SUSE Linux) 9.3.1 20200406 [revision 6db837a5288ee3ca5ec504fbd5a765817e556ac2], clang version 10.0.0
58 oraclelinux:6 : Ok gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-23.0.1)
59 oraclelinux:7 : Ok gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39.0.3)
60 oraclelinux:8 : Ok gcc (GCC) 8.3.1 20191121 (Red Hat 8.3.1-5.0.3), clang version 9.0.1 (Red Hat 9.0.1-2.0.1.module+el8.2.0+5599+9ed9ef6d)
61 ubuntu:12.04 : Ok gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, Ubuntu clang version 3.0-6ubuntu3 (tags/RELEASE_30/final) (based on LLVM 3.0)
62 ubuntu:14.04 : Ok gcc (Ubuntu 4.8.4-2ubuntu1~14.04.4) 4.8.4
63 ubuntu:16.04 : Ok gcc (Ubuntu 5.4.0-6ubuntu1~16.04.12) 5.4.0 20160609, clang version 3.8.0-2ubuntu4 (tags/RELEASE_380/final)
64 ubuntu:16.04-x-arm : Ok arm-linux-gnueabihf-gcc (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
65 ubuntu:16.04-x-arm64 : Ok aarch64-linux-gnu-gcc (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
66 ubuntu:16.04-x-powerpc : Ok powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
67 ubuntu:16.04-x-powerpc64 : Ok powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
68 ubuntu:16.04-x-powerpc64el : Ok powerpc64le-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
69 ubuntu:16.04-x-s390 : Ok s390x-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
70 ubuntu:18.04 : Ok gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0, clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
71 ubuntu:18.04-x-arm : Ok arm-linux-gnueabihf-gcc (Ubuntu/Linaro 7.5.0-3ubuntu1~18.04) 7.5.0
72 ubuntu:18.04-x-arm64 : Ok aarch64-linux-gnu-gcc (Ubuntu/Linaro 7.5.0-3ubuntu1~18.04) 7.5.0
73 ubuntu:18.04-x-m68k : Ok m68k-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
74 ubuntu:18.04-x-powerpc : Ok powerpc-linux-gnu-gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0
75 ubuntu:18.04-x-powerpc64 : Ok powerpc64-linux-gnu-gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0
76 ubuntu:18.04-x-powerpc64el : Ok powerpc64le-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
77 ubuntu:18.04-x-riscv64 : Ok riscv64-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
78 ubuntu:18.04-x-s390 : Ok s390x-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
79 ubuntu:18.04-x-sh4 : Ok sh4-linux-gnu-gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0
80 ubuntu:18.04-x-sparc64 : Ok sparc64-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
81 ubuntu:18.10 : Ok gcc (Ubuntu 8.3.0-6ubuntu1~18.10.1) 8.3.0, clang version 7.0.0-3 (tags/RELEASE_700/final)
82 ubuntu:19.04 : Ok gcc (Ubuntu 8.3.0-6ubuntu1) 8.3.0, clang version 8.0.0-3 (tags/RELEASE_800/final)
83 ubuntu:19.04-x-alpha : Ok alpha-linux-gnu-gcc (Ubuntu 8.3.0-6ubuntu1) 8.3.0
84 ubuntu:19.04-x-arm64 : Ok aarch64-linux-gnu-gcc (Ubuntu/Linaro 8.3.0-6ubuntu1) 8.3.0
85 ubuntu:19.04-x-hppa : Ok hppa-linux-gnu-gcc (Ubuntu 8.3.0-6ubuntu1) 8.3.0
86 ubuntu:19.10 : FAIL gcc (Ubuntu 9.2.1-9ubuntu2) 9.2.1 20191008, clang version 9.0.0-2 (tags/RELEASE_900/final)
87 ubuntu:20.04 : Ok gcc (Ubuntu 9.3.0-10ubuntu2) 9.3.0, clang version 10.0.0-4ubuntu1
#
It builds ok with the default set of options.
The "7: Simple expression parser" entry is failing due to a bug in the
hashmap in libbpf that will hit upstream via the bpf tree.
# uname -a
Linux five 5.5.17-200.fc31.x86_64 #1 SMP Mon Apr 13 15:29:42 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
# git log --oneline -1
3e9b26dc2268 perf tools: Remove some duplicated includes
# perf version --build-options
perf version 5.7.rc7.g0affd0e5262b
dwarf: [ on ] # HAVE_DWARF_SUPPORT
dwarf_getlocations: [ on ] # HAVE_DWARF_GETLOCATIONS_SUPPORT
glibc: [ on ] # HAVE_GLIBC_SUPPORT
gtk2: [ on ] # HAVE_GTK2_SUPPORT
syscall_table: [ on ] # HAVE_SYSCALL_TABLE_SUPPORT
libbfd: [ on ] # HAVE_LIBBFD_SUPPORT
libelf: [ on ] # HAVE_LIBELF_SUPPORT
libnuma: [ on ] # HAVE_LIBNUMA_SUPPORT
numa_num_possible_cpus: [ on ] # HAVE_LIBNUMA_SUPPORT
libperl: [ on ] # HAVE_LIBPERL_SUPPORT
libpython: [ on ] # HAVE_LIBPYTHON_SUPPORT
libslang: [ on ] # HAVE_SLANG_SUPPORT
libcrypto: [ on ] # HAVE_LIBCRYPTO_SUPPORT
libunwind: [ on ] # HAVE_LIBUNWIND_SUPPORT
libdw-dwarf-unwind: [ on ] # HAVE_DWARF_SUPPORT
zlib: [ on ] # HAVE_ZLIB_SUPPORT
lzma: [ on ] # HAVE_LZMA_SUPPORT
get_cpuid: [ on ] # HAVE_AUXTRACE_SUPPORT
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
aio: [ on ] # HAVE_AIO_SUPPORT
zstd: [ on ] # HAVE_ZSTD_SUPPORT
# perf test
1: vmlinux symtab matches kallsyms : Ok
2: Detect openat syscall event : Ok
3: Detect openat syscall event on all cpus : Ok
4: Read samples using the mmap interface : Ok
5: Test data source output : Ok
6: Parse event definition strings : Ok
7: Simple expression parser : FAILED!
8: PERF_RECORD_* events & perf_sample fields : Ok
9: Parse perf pmu format : Ok
10: PMU events :
10.1: PMU event table sanity : Ok
10.2: PMU event map aliases : Ok
10.3: Parsing of PMU event table metrics : Ok
11: DSO data read : Ok
12: DSO data cache : Ok
13: DSO data reopen : Ok
14: Roundtrip evsel->name : Ok
15: Parse sched tracepoints fields : Ok
16: syscalls:sys_enter_openat event fields : Ok
17: Setup struct perf_event_attr : Ok
18: Match and link multiple hists : Ok
19: 'import perf' in python : Ok
20: Breakpoint overflow signal handler : Ok
21: Breakpoint overflow sampling : Ok
22: Breakpoint accounting : Ok
23: Watchpoint :
23.1: Read Only Watchpoint : Skip
23.2: Write Only Watchpoint : Ok
23.3: Read / Write Watchpoint : Ok
23.4: Modify Watchpoint : Ok
24: Number of exit events of a simple workload : Ok
25: Software clock events period values : Ok
26: Object code reading : Ok
27: Sample parsing : Ok
28: Use a dummy software event to keep tracking : Ok
29: Parse with no sample_id_all bit set : Ok
30: Filter hist entries : Ok
31: Lookup mmap thread : Ok
32: Share thread maps : Ok
33: Sort output of hist entries : Ok
34: Cumulate child hist entries : Ok
35: Track with sched_switch : Ok
36: Filter fds with revents mask in a fdarray : Ok
37: Add fd to a fdarray, making it autogrow : Ok
38: kmod_path__parse : Ok
39: Thread map : Ok
40: LLVM search and compile :
40.1: Basic BPF llvm compile : Ok
40.2: kbuild searching : Ok
40.3: Compile source for BPF prologue generation : Ok
40.4: Compile source for BPF relocation : Ok
41: Session topology : Ok
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
42.4: BPF relocation checker : Ok
43: Synthesize thread map : Ok
44: Remove thread map : Ok
45: Synthesize cpu map : Ok
46: Synthesize stat config : Ok
47: Synthesize stat : Ok
48: Synthesize stat round : Ok
49: Synthesize attr update : Ok
50: Event times : Ok
51: Read backward ring buffer : Ok
52: Print cpu map : Ok
53: Merge cpu map : Ok
54: Probe SDT events : Ok
55: is_printable_array : Ok
56: Print bitmap : Ok
57: perf hooks : Ok
58: builtin clang support : Skip (not compiled in)
59: unit_number__scnprintf : Ok
60: mem2node : Ok
61: time utils : Ok
62: Test jit_write_elf : Ok
63: Test libpfm4 support : Skip (not compiled in)
64: Test api io : Ok
65: maps__merge_in : Ok
66: Demangle Java : Ok
67: x86 rdpmc : Ok
68: Convert perf time to TSC : Ok
69: DWARF unwind : Ok
70: x86 instruction decoder - new instructions : Ok
71: Intel PT packet decoder : Ok
72: x86 bp modify : Ok
73: probe libc's inet_pton & backtrace it with ping : Ok
74: Use vfs_getname probe to get syscall args filenames : Ok
75: Check open filename arg using perf trace + vfs_getname: Ok
76: Zstd perf.data compression/decompression : Ok
77: Add vfs_getname probe to get syscall args filenames : Ok
#
[acme@five perf]$ git log --oneline -1 ; time make -C tools/perf build-test
3e9b26dc2268 (HEAD -> perf/core, seventh/perf/core, quaco/perf/core) perf tools: Remove some duplicated includes
make: Entering directory '/home/acme/git/perf/tools/perf'
- tarpkg: ./tests/perf-targz-src-pkg .
make_no_libbpf_DEBUG_O: make NO_LIBBPF=1 DEBUG=1
make_with_clangllvm_O: make LIBCLANGLLVM=1
make_no_auxtrace_O: make NO_AUXTRACE=1
make_no_demangle_O: make NO_DEMANGLE=1
make_clean_all_O: make clean all
make_util_pmu_bison_o_O: make util/pmu-bison.o
make_no_newt_O: make NO_NEWT=1
make_no_gtk2_O: make NO_GTK2=1
make_no_libbpf_O: make NO_LIBBPF=1
make_no_libaudit_O: make NO_LIBAUDIT=1
make_perf_o_O: make perf.o
make_no_libelf_O: make NO_LIBELF=1
make_static_O: make LDFLAGS=-static NO_PERF_READ_VDSO32=1 NO_PERF_READ_VDSOX32=1 NO_JVMTI=1
make_install_O: make install
make_no_libpython_O: make NO_LIBPYTHON=1
make_no_libunwind_O: make NO_LIBUNWIND=1
make_no_libdw_dwarf_unwind_O: make NO_LIBDW_DWARF_UNWIND=1
make_no_scripts_O: make NO_LIBPYTHON=1 NO_LIBPERL=1
make_with_libpfm4_O: make LIBPFM4=1
make_pure_O: make
make_doc_O: make doc
make_no_sdt_O: make NO_SDT=1
make_no_slang_O: make NO_SLANG=1
make_no_syscall_tbl_O: make NO_SYSCALL_TABLE=1
make_install_bin_O: make install-bin
make_no_libperl_O: make NO_LIBPERL=1
make_install_prefix_slash_O: make install prefix=/tmp/krava/
make_install_prefix_O: make install prefix=/tmp/krava
make_no_ui_O: make NO_NEWT=1 NO_SLANG=1 NO_GTK2=1
make_no_libnuma_O: make NO_LIBNUMA=1
make_minimal_O: make NO_LIBPERL=1 NO_LIBPYTHON=1 NO_NEWT=1 NO_GTK2=1 NO_DEMANGLE=1 NO_LIBELF=1 NO_LIBUNWIND=1 NO_BACKTRACE=1 NO_LIBNUMA=1 NO_LIBAUDIT=1 NO_LIBBIONIC=1 NO_LIBDW_DWARF_UNWIND=1 NO_AUXTRACE=1 NO_LIBBPF=1 NO_LIBCRYPTO=1 NO_SDT=1 NO_JVMTI=1 NO_LIBZSTD=1 NO_LIBCAP=1 NO_SYSCALL_TABLE=1
make_with_babeltrace_O: make LIBBABELTRACE=1
make_help_O: make help
make_no_libcrypto_O: make NO_LIBCRYPTO=1
make_debug_O: make DEBUG=1
make_no_libbionic_O: make NO_LIBBIONIC=1
make_no_backtrace_O: make NO_BACKTRACE=1
make_tags_O: make tags
make_util_map_o_O: make util/map.o
OK
make: Leaving directory '/home/acme/git/perf/tools/perf'
[acme@five perf]$
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXtaWmgAKCRCyPKLppCJ+
J4mdAQD9wzSFCI96jZkWvCx61AkoZkcG8fyaWBpH+7Wuum3J1QD/Q9c37NGepK3T
/sMFKufuBF7Z0Uy2toMz9i9P/KLaEQI=
=dNn2
-----END PGP SIGNATURE-----
Merge tag 'perf-tools-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tooling updates from Arnaldo Carvalho de Melo:
"These are additional changes to the perf tools, on top of what Ingo
already submitted.
- Further Intel PT call-trace fixes
- Improve SELinux docs and tool warnings
- Fix race at exit in 'perf record' using eventfd.
- Add missing build tests to the default set of 'make -C tools/perf
build-test'
- Sync msr-index.h getting new AMD MSRs to decode and filter in 'perf
trace'.
- Fix fallback to libaudit in 'perf trace' for arches not using
per-arch *.tbl files.
- Fixes for 'perf ftrace'.
- Fixes and improvements for the 'perf stat' metrics.
- Use dummy event to get PERF_RECORD_{FORK,MMAP,etc} while
synthesizing those metadata events for pre-existing threads.
- Fix leaks detected using clang tooling.
- Improvements to PMU event metric testing.
- Report summary for 'perf stat' interval mode at the end, summing up
all the intervals.
- Improve pipe mode, i.e. this now works as expected, continuously
dumping samples:
# perf record -g -e raw_syscalls:sys_enter | perf --no-pager script
- Fixes for event grouping, detecting incompatible groups such as:
# perf stat -e '{cycles,power/energy-cores/}' -v
WARNING: group events cpu maps do not match, disabling group:
anon group { power/energy-cores/, cycles }
power/energy-cores/: 0
cycles: 0-7
- Fixes for 'perf probe': blacklist address checking, number of
kretprobe instances, etc.
- JIT processing improvements and fixes plus the addition of a 'perf
test' entry for the java demangler.
- Add support for synthesizing first/last level cache, TLB and remove
access events from HW tracing in the auxtrace code, first to use is
ARM SPE.
- Vendor events updates and fixes, including for POWER9 and Intel.
- Allow using ~/.perfconfig for removing the ',' separators in 'perf
stat' output.
- Opt-in support for libpfm4"
* tag 'perf-tools-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (120 commits)
perf tools: Remove some duplicated includes
perf symbols: Fix kernel maps for kcore and eBPF
tools arch x86: Sync the msr-index.h copy with the kernel sources
perf stat: Ensure group is defined on top of the same cpu mask
perf libdw: Fix off-by 1 relative directory includes
perf arm-spe: Support synthetic events
perf auxtrace: Add four itrace options
perf tools: Move arm-spe-pkt-decoder.h/c to the new dir
perf test: Initialize memory in dwarf-unwind
perf tests: Don't tail call optimize in unwind test
tools compiler.h: Add attribute to disable tail calls
perf build: Add a LIBPFM4=1 build test entry
perf tools: Add optional support for libpfm4
perf tools: Correct license on jsmn JSON parser
perf jit: Fix inaccurate DWARF line table
perf jvmti: Remove redundant jitdump line table entries
perf build: Add NO_SDT=1 to the default set of build tests
perf build: Add NO_LIBCRYPTO=1 to the default set of build tests
perf build: Add NO_SYSCALL_TABLE=1 to the build tests
perf build: Remove libaudit from the default feature checks
...
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
Add a bpf_csum_level() helper which BPF programs can use in combination
with bpf_skb_adjust_room() when they pass in BPF_F_ADJ_ROOM_NO_CSUM_RESET
flag to the latter to avoid falling back to CHECKSUM_NONE.
The bpf_csum_level() allows to adjust CHECKSUM_UNNECESSARY skb->csum_levels
via BPF_CSUM_LEVEL_{INC,DEC} which calls __skb_{incr,decr}_checksum_unnecessary()
on the skb. The helper also allows a BPF_CSUM_LEVEL_RESET which sets the skb's
csum to CHECKSUM_NONE as well as a BPF_CSUM_LEVEL_QUERY to just return the
current level. Without this helper, there is no way to otherwise adjust the
skb->csum_level. I did not add an extra dummy flags as there is plenty of free
bitspace in level argument itself iff ever needed in future.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/279ae3717cb3d03c0ffeb511493c93c450a01e1a.1591108731.git.daniel@iogearbox.net
Lorenz recently reported:
In our TC classifier cls_redirect [0], we use the following sequence of
helper calls to decapsulate a GUE (basically IP + UDP + custom header)
encapsulated packet:
bpf_skb_adjust_room(skb, -encap_len, BPF_ADJ_ROOM_MAC, BPF_F_ADJ_ROOM_FIXED_GSO)
bpf_redirect(skb->ifindex, BPF_F_INGRESS)
It seems like some checksums of the inner headers are not validated in
this case. For example, a TCP SYN packet with invalid TCP checksum is
still accepted by the network stack and elicits a SYN ACK. [...]
That is, we receive the following packet from the driver:
| ETH | IP | UDP | GUE | IP | TCP |
skb->ip_summed == CHECKSUM_UNNECESSARY
ip_summed is CHECKSUM_UNNECESSARY because our NICs do rx checksum offloading.
On this packet we run skb_adjust_room_mac(-encap_len), and get the following:
| ETH | IP | TCP |
skb->ip_summed == CHECKSUM_UNNECESSARY
Note that ip_summed is still CHECKSUM_UNNECESSARY. After bpf_redirect()'ing
into the ingress, we end up in tcp_v4_rcv(). There, skb_checksum_init() is
turned into a no-op due to CHECKSUM_UNNECESSARY.
The bpf_skb_adjust_room() helper is not aware of protocol specifics. Internally,
it handles the CHECKSUM_COMPLETE case via skb_postpull_rcsum(), but that does
not cover CHECKSUM_UNNECESSARY. In this case skb->csum_level of the original
skb prior to bpf_skb_adjust_room() call was 0, that is, covering UDP. Right now
there is no way to adjust the skb->csum_level. NICs that have checksum offload
disabled (CHECKSUM_NONE) or that support CHECKSUM_COMPLETE are not affected.
Use a safe default for CHECKSUM_UNNECESSARY by resetting to CHECKSUM_NONE and
add a flag to the helper called BPF_F_ADJ_ROOM_NO_CSUM_RESET that allows users
from opting out. Opting out is useful for the case where we don't remove/add
full protocol headers, or for the case where a user wants to adjust the csum
level manually e.g. through bpf_csum_level() helper that is added in subsequent
patch.
The bpf_skb_proto_{4_to_6,6_to_4}() for NAT64/46 translation from the BPF
bpf_skb_change_proto() helper uses bpf_skb_net_hdr_{push,pop}() pair internally
as well but doesn't change layers, only transitions between v4 to v6 and vice
versa, therefore no adoption is required there.
[0] https://lore.kernel.org/bpf/20200424185556.7358-1-lmb@cloudflare.com/
Fixes: 2be7e212d541 ("bpf: add bpf_skb_adjust_room helper")
Reported-by: Lorenz Bauer <lmb@cloudflare.com>
Reported-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/CACAyw9-uU_52esMd1JjuA80fRPHJv5vsSg8GnfW3t_qDU4aVKQ@mail.gmail.com/
Link: https://lore.kernel.org/bpf/11a90472e7cce83e76ddbfce81fdfce7bfc68808.1591108731.git.daniel@iogearbox.net
Pull vfs updates from Al Viro:
"Assorted patches from Miklos.
An interesting part here is /proc/mounts stuff..."
The "/proc/mounts stuff" is using a cursor for keeeping the location
data while traversing the mount listing.
Also probably worth noting is the addition of faccessat2(), which takes
an additional set of flags to specify how the lookup is done
(AT_EACCESS, AT_SYMLINK_NOFOLLOW, AT_EMPTY_PATH).
* 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: add faccessat2 syscall
vfs: don't parse "silent" option
vfs: don't parse "posixacl" option
vfs: don't parse forbidden flags
statx: add mount_root
statx: add mount ID
statx: don't clear STATX_ATIME on SB_RDONLY
uapi: deprecate STATX_ALL
utimensat: AT_EMPTY_PATH support
vfs: split out access_override_creds()
proc/mounts: add cursor
aio: fix async fsync creds
vfs: allow unprivileged whiteout creation
set from Mauro toward the completion of the RST conversion. I *really*
hope we are getting close to the end of this. Meanwhile, those patches
reach pretty far afield to update document references around the tree;
there should be no actual code changes there. There will be, alas, more of
the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots of
fixes.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl7VId8PHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Yq/gH/iaDgirQZV6UZ2v9sfwQNYolNpf2sKAuOZjd
bPFB7WJoMQbKwQEvYrAUL2+5zPOcLYuIfzyOfo1BV1py+EyKbACcKjI4AedxfJF7
+NchmOBhlEqmEhzx2U08HRc4/8J223WG17fJRVsV3p+opJySexSFeQucfOciX5NR
RUCxweWWyg/FgyqjkyMMTtsePqZPmcT5dWTlVXISlbWzcv5NFhuJXnSrw8Sfzcmm
SJMzqItv3O+CabnKQ8kMLV2PozXTMfjeWH47ZUK0Y8/8PP9+cvqwFzZ0UDQJ1Xaz
oyW/TqmunaXhfMsMFeFGSwtfgwRHvXdxkQdtwNHvo1dV4dzTvDw=
=fDC/
-----END PGP SIGNATURE-----
Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"
* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
Extend bpf() syscall subcommands that operate on bpf_link, that is
LINK_CREATE, LINK_UPDATE, OBJ_GET_INFO, to accept attach types tied to
network namespaces (only flow dissector at the moment).
Link-based and prog-based attachment can be used interchangeably, but only
one can exist at a time. Attempts to attach a link when a prog is already
attached directly, and the other way around, will be met with -EEXIST.
Attempts to detach a program when link exists result in -EINVAL.
Attachment of multiple links of same attach type to one netns is not
supported with the intention to lift the restriction when a use-case
presents itself. Because of that link create returns -E2BIG when trying to
create another netns link, when one already exists.
Link-based attachments to netns don't keep a netns alive by holding a ref
to it. Instead links get auto-detached from netns when the latter is being
destroyed, using a pernet pre_exit callback.
When auto-detached, link lives in defunct state as long there are open FDs
for it. -ENOLINK is returned if a user tries to update a defunct link.
Because bpf_link to netns doesn't hold a ref to struct net, special care is
taken when releasing, updating, or filling link info. The netns might be
getting torn down when any of these link operations are in progress. That
is why auto-detach and update/release/fill_info are synchronized by the
same mutex. Also, link ops have to always check if auto-detach has not
happened yet and if netns is still alive (refcnt > 0).
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-5-jakub@cloudflare.com
Add xdp_txq_info as the Tx counterpart to xdp_rxq_info. At the
moment only the device is added. Other fields (queue_index)
can be added as use cases arise.
>From a UAPI perspective, add egress_ifindex to xdp context for
bpf programs to see the Tx device.
Update the verifier to only allow accesses to egress_ifindex by
XDP programs with BPF_XDP_DEVMAP expected attach type.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200529220716.75383-4-dsahern@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add BPF_XDP_DEVMAP attach type for use with programs associated with a
DEVMAP entry.
Allow DEVMAPs to associate a program with a device entry by adding
a bpf_prog.fd to 'struct bpf_devmap_val'. Values read show the program
id, so the fd and id are a union. bpf programs can get access to the
struct via vmlinux.h.
The program associated with the fd must have type XDP with expected
attach type BPF_XDP_DEVMAP. When a program is associated with a device
index, the program is run on an XDP_REDIRECT and before the buffer is
added to the per-cpu queue. At this point rxq data is still valid; the
next patch adds tx device information allowing the prorgam to see both
ingress and egress device indices.
XDP generic is skb based and XDP programs do not work with skb's. Block
the use case by walking maps used by a program that is to be attached
via xdpgeneric and fail if any of them are DEVMAP / DEVMAP_HASH with
Block attach of BPF_XDP_DEVMAP programs to devices.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200529220716.75383-3-dsahern@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit adds a new MPSC ring buffer implementation into BPF ecosystem,
which allows multiple CPUs to submit data to a single shared ring buffer. On
the consumption side, only single consumer is assumed.
Motivation
----------
There are two distinctive motivators for this work, which are not satisfied by
existing perf buffer, which prompted creation of a new ring buffer
implementation.
- more efficient memory utilization by sharing ring buffer across CPUs;
- preserving ordering of events that happen sequentially in time, even
across multiple CPUs (e.g., fork/exec/exit events for a task).
These two problems are independent, but perf buffer fails to satisfy both.
Both are a result of a choice to have per-CPU perf ring buffer. Both can be
also solved by having an MPSC implementation of ring buffer. The ordering
problem could technically be solved for perf buffer with some in-kernel
counting, but given the first one requires an MPSC buffer, the same solution
would solve the second problem automatically.
Semantics and APIs
------------------
Single ring buffer is presented to BPF programs as an instance of BPF map of
type BPF_MAP_TYPE_RINGBUF. Two other alternatives considered, but ultimately
rejected.
One way would be to, similar to BPF_MAP_TYPE_PERF_EVENT_ARRAY, make
BPF_MAP_TYPE_RINGBUF could represent an array of ring buffers, but not enforce
"same CPU only" rule. This would be more familiar interface compatible with
existing perf buffer use in BPF, but would fail if application needed more
advanced logic to lookup ring buffer by arbitrary key. HASH_OF_MAPS addresses
this with current approach. Additionally, given the performance of BPF
ringbuf, many use cases would just opt into a simple single ring buffer shared
among all CPUs, for which current approach would be an overkill.
Another approach could introduce a new concept, alongside BPF map, to
represent generic "container" object, which doesn't necessarily have key/value
interface with lookup/update/delete operations. This approach would add a lot
of extra infrastructure that has to be built for observability and verifier
support. It would also add another concept that BPF developers would have to
familiarize themselves with, new syntax in libbpf, etc. But then would really
provide no additional benefits over the approach of using a map.
BPF_MAP_TYPE_RINGBUF doesn't support lookup/update/delete operations, but so
doesn't few other map types (e.g., queue and stack; array doesn't support
delete, etc).
The approach chosen has an advantage of re-using existing BPF map
infrastructure (introspection APIs in kernel, libbpf support, etc), being
familiar concept (no need to teach users a new type of object in BPF program),
and utilizing existing tooling (bpftool). For common scenario of using
a single ring buffer for all CPUs, it's as simple and straightforward, as
would be with a dedicated "container" object. On the other hand, by being
a map, it can be combined with ARRAY_OF_MAPS and HASH_OF_MAPS map-in-maps to
implement a wide variety of topologies, from one ring buffer for each CPU
(e.g., as a replacement for perf buffer use cases), to a complicated
application hashing/sharding of ring buffers (e.g., having a small pool of
ring buffers with hashed task's tgid being a look up key to preserve order,
but reduce contention).
Key and value sizes are enforced to be zero. max_entries is used to specify
the size of ring buffer and has to be a power of 2 value.
There are a bunch of similarities between perf buffer
(BPF_MAP_TYPE_PERF_EVENT_ARRAY) and new BPF ring buffer semantics:
- variable-length records;
- if there is no more space left in ring buffer, reservation fails, no
blocking;
- memory-mappable data area for user-space applications for ease of
consumption and high performance;
- epoll notifications for new incoming data;
- but still the ability to do busy polling for new data to achieve the
lowest latency, if necessary.
BPF ringbuf provides two sets of APIs to BPF programs:
- bpf_ringbuf_output() allows to *copy* data from one place to a ring
buffer, similarly to bpf_perf_event_output();
- bpf_ringbuf_reserve()/bpf_ringbuf_commit()/bpf_ringbuf_discard() APIs
split the whole process into two steps. First, a fixed amount of space is
reserved. If successful, a pointer to a data inside ring buffer data area
is returned, which BPF programs can use similarly to a data inside
array/hash maps. Once ready, this piece of memory is either committed or
discarded. Discard is similar to commit, but makes consumer ignore the
record.
bpf_ringbuf_output() has disadvantage of incurring extra memory copy, because
record has to be prepared in some other place first. But it allows to submit
records of the length that's not known to verifier beforehand. It also closely
matches bpf_perf_event_output(), so will simplify migration significantly.
bpf_ringbuf_reserve() avoids the extra copy of memory by providing a memory
pointer directly to ring buffer memory. In a lot of cases records are larger
than BPF stack space allows, so many programs have use extra per-CPU array as
a temporary heap for preparing sample. bpf_ringbuf_reserve() avoid this needs
completely. But in exchange, it only allows a known constant size of memory to
be reserved, such that verifier can verify that BPF program can't access
memory outside its reserved record space. bpf_ringbuf_output(), while slightly
slower due to extra memory copy, covers some use cases that are not suitable
for bpf_ringbuf_reserve().
The difference between commit and discard is very small. Discard just marks
a record as discarded, and such records are supposed to be ignored by consumer
code. Discard is useful for some advanced use-cases, such as ensuring
all-or-nothing multi-record submission, or emulating temporary malloc()/free()
within single BPF program invocation.
Each reserved record is tracked by verifier through existing
reference-tracking logic, similar to socket ref-tracking. It is thus
impossible to reserve a record, but forget to submit (or discard) it.
bpf_ringbuf_query() helper allows to query various properties of ring buffer.
Currently 4 are supported:
- BPF_RB_AVAIL_DATA returns amount of unconsumed data in ring buffer;
- BPF_RB_RING_SIZE returns the size of ring buffer;
- BPF_RB_CONS_POS/BPF_RB_PROD_POS returns current logical possition of
consumer/producer, respectively.
Returned values are momentarily snapshots of ring buffer state and could be
off by the time helper returns, so this should be used only for
debugging/reporting reasons or for implementing various heuristics, that take
into account highly-changeable nature of some of those characteristics.
One such heuristic might involve more fine-grained control over poll/epoll
notifications about new data availability in ring buffer. Together with
BPF_RB_NO_WAKEUP/BPF_RB_FORCE_WAKEUP flags for output/commit/discard helpers,
it allows BPF program a high degree of control and, e.g., more efficient
batched notifications. Default self-balancing strategy, though, should be
adequate for most applications and will work reliable and efficiently already.
Design and implementation
-------------------------
This reserve/commit schema allows a natural way for multiple producers, either
on different CPUs or even on the same CPU/in the same BPF program, to reserve
independent records and work with them without blocking other producers. This
means that if BPF program was interruped by another BPF program sharing the
same ring buffer, they will both get a record reserved (provided there is
enough space left) and can work with it and submit it independently. This
applies to NMI context as well, except that due to using a spinlock during
reservation, in NMI context, bpf_ringbuf_reserve() might fail to get a lock,
in which case reservation will fail even if ring buffer is not full.
The ring buffer itself internally is implemented as a power-of-2 sized
circular buffer, with two logical and ever-increasing counters (which might
wrap around on 32-bit architectures, that's not a problem):
- consumer counter shows up to which logical position consumer consumed the
data;
- producer counter denotes amount of data reserved by all producers.
Each time a record is reserved, producer that "owns" the record will
successfully advance producer counter. At that point, data is still not yet
ready to be consumed, though. Each record has 8 byte header, which contains
the length of reserved record, as well as two extra bits: busy bit to denote
that record is still being worked on, and discard bit, which might be set at
commit time if record is discarded. In the latter case, consumer is supposed
to skip the record and move on to the next one. Record header also encodes
record's relative offset from the beginning of ring buffer data area (in
pages). This allows bpf_ringbuf_commit()/bpf_ringbuf_discard() to accept only
the pointer to the record itself, without requiring also the pointer to ring
buffer itself. Ring buffer memory location will be restored from record
metadata header. This significantly simplifies verifier, as well as improving
API usability.
Producer counter increments are serialized under spinlock, so there is
a strict ordering between reservations. Commits, on the other hand, are
completely lockless and independent. All records become available to consumer
in the order of reservations, but only after all previous records where
already committed. It is thus possible for slow producers to temporarily hold
off submitted records, that were reserved later.
Reservation/commit/consumer protocol is verified by litmus tests in
Documentation/litmus-test/bpf-rb.
One interesting implementation bit, that significantly simplifies (and thus
speeds up as well) implementation of both producers and consumers is how data
area is mapped twice contiguously back-to-back in the virtual memory. This
allows to not take any special measures for samples that have to wrap around
at the end of the circular buffer data area, because the next page after the
last data page would be first data page again, and thus the sample will still
appear completely contiguous in virtual memory. See comment and a simple ASCII
diagram showing this visually in bpf_ringbuf_area_alloc().
Another feature that distinguishes BPF ringbuf from perf ring buffer is
a self-pacing notifications of new data being availability.
bpf_ringbuf_commit() implementation will send a notification of new record
being available after commit only if consumer has already caught up right up
to the record being committed. If not, consumer still has to catch up and thus
will see new data anyways without needing an extra poll notification.
Benchmarks (see tools/testing/selftests/bpf/benchs/bench_ringbuf.c) show that
this allows to achieve a very high throughput without having to resort to
tricks like "notify only every Nth sample", which are necessary with perf
buffer. For extreme cases, when BPF program wants more manual control of
notifications, commit/discard/output helpers accept BPF_RB_NO_WAKEUP and
BPF_RB_FORCE_WAKEUP flags, which give full control over notifications of data
availability, but require extra caution and diligence in using this API.
Comparison to alternatives
--------------------------
Before considering implementing BPF ring buffer from scratch existing
alternatives in kernel were evaluated, but didn't seem to meet the needs. They
largely fell into few categores:
- per-CPU buffers (perf, ftrace, etc), which don't satisfy two motivations
outlined above (ordering and memory consumption);
- linked list-based implementations; while some were multi-producer designs,
consuming these from user-space would be very complicated and most
probably not performant; memory-mapping contiguous piece of memory is
simpler and more performant for user-space consumers;
- io_uring is SPSC, but also requires fixed-sized elements. Naively turning
SPSC queue into MPSC w/ lock would have subpar performance compared to
locked reserve + lockless commit, as with BPF ring buffer. Fixed sized
elements would be too limiting for BPF programs, given existing BPF
programs heavily rely on variable-sized perf buffer already;
- specialized implementations (like a new printk ring buffer, [0]) with lots
of printk-specific limitations and implications, that didn't seem to fit
well for intended use with BPF programs.
[0] https://lwn.net/Articles/779550/
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-2-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tail call optimizations can remove stack frames that are used in
unwinding tests. Add an attribute that can be used to disable the tail
call optimization. Tested on clang and GCC.
Committer notes:
Old versions of clang don't like that __attribute__((optimize)), so add
an ifdef to make it go away.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: clang-built-linux@googlegroups.com
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200530082015.39162-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As stated in 983695fa6765 ("bpf: fix unconnected udp hooks"), the objective
for the existing cgroup connect/sendmsg/recvmsg/bind BPF hooks is to be
transparent to applications. In Cilium we make use of these hooks [0] in
order to enable E-W load balancing for existing Kubernetes service types
for all Cilium managed nodes in the cluster. Those backends can be local
or remote. The main advantage of this approach is that it operates as close
as possible to the socket, and therefore allows to avoid packet-based NAT
given in connect/sendmsg/recvmsg hooks we only need to xlate sock addresses.
This also allows to expose NodePort services on loopback addresses in the
host namespace, for example. As another advantage, this also efficiently
blocks bind requests for applications in the host namespace for exposed
ports. However, one missing item is that we also need to perform reverse
xlation for inet{,6}_getname() hooks such that we can return the service
IP/port tuple back to the application instead of the remote peer address.
The vast majority of applications does not bother about getpeername(), but
in a few occasions we've seen breakage when validating the peer's address
since it returns unexpectedly the backend tuple instead of the service one.
Therefore, this trivial patch allows to customise and adds a getpeername()
as well as getsockname() BPF cgroup hook for both IPv4 and IPv6 in order
to address this situation.
Simple example:
# ./cilium/cilium service list
ID Frontend Service Type Backend
1 1.2.3.4:80 ClusterIP 1 => 10.0.0.10:80
Before; curl's verbose output example, no getpeername() reverse xlation:
# curl --verbose 1.2.3.4
* Rebuilt URL to: 1.2.3.4/
* Trying 1.2.3.4...
* TCP_NODELAY set
* Connected to 1.2.3.4 (10.0.0.10) port 80 (#0)
> GET / HTTP/1.1
> Host: 1.2.3.4
> User-Agent: curl/7.58.0
> Accept: */*
[...]
After; with getpeername() reverse xlation:
# curl --verbose 1.2.3.4
* Rebuilt URL to: 1.2.3.4/
* Trying 1.2.3.4...
* TCP_NODELAY set
* Connected to 1.2.3.4 (1.2.3.4) port 80 (#0)
> GET / HTTP/1.1
> Host: 1.2.3.4
> User-Agent: curl/7.58.0
> Accept: */*
[...]
Originally, I had both under a BPF_CGROUP_INET{4,6}_GETNAME type and exposed
peer to the context similar as in inet{,6}_getname() fashion, but API-wise
this is suboptimal as it always enforces programs having to test for ctx->peer
which can easily be missed, hence BPF_CGROUP_INET{4,6}_GET{PEER,SOCK}NAME split.
Similarly, the checked return code is on tnum_range(1, 1), but if a use case
comes up in future, it can easily be changed to return an error code instead.
Helper and ctx member access is the same as with connect/sendmsg/etc hooks.
[0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/61a479d759b2482ae3efb45546490bacd796a220.1589841594.git.daniel@iogearbox.net
With having ability to lookup sockets in cgroup skb programs it becomes
useful to access cgroup id of retrieved sockets so that policies can be
implemented based on origin cgroup of such socket.
For example, a container running in a cgroup can have cgroup skb ingress
program that can lookup peer socket that is sending packets to a process
inside the container and decide whether those packets should be allowed
or denied based on cgroup id of the peer.
More specifically such ingress program can implement intra-host policy
"allow incoming packets only from this same container and not from any
other container on same host" w/o relying on source IP addresses since
quite often it can be the case that containers share same IP address on
the host.
Introduce two new helpers for this use-case: bpf_sk_cgroup_id() and
bpf_sk_ancestor_cgroup_id().
These helpers are similar to existing bpf_skb_{,ancestor_}cgroup_id
helpers with the only difference that sk is used to get cgroup id
instead of skb, and share code with them.
See documentation in UAPI for more details.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/f5884981249ce911f63e9b57ecd5d7d19154ff39.1589486450.git.rdna@fb.com
bpf_sock_addr.user_port supports only 4-byte load and it leads to ugly
code in BPF programs, like:
volatile __u32 user_port = ctx->user_port;
__u16 port = bpf_ntohs(user_port);
Since otherwise clang may optimize the load to be 2-byte and it's
rejected by verifier.
Add support for 1- and 2-byte loads same way as it's supported for other
fields in bpf_sock_addr like user_ip4, msg_src_ip4, etc.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/c1e983f4c17573032601d0b2b1f9d1274f24bc16.1589420814.git.rdna@fb.com
Constants of the *_ALL type can be actively harmful due to the fact that
developers will usually fail to consider the possible effects of future
changes to the definition.
Deprecate STATX_ALL in the uapi, while no damage has been done yet.
We could keep something like this around in the kernel, but there's
actually no point, since all filesystems should be explicitly checking
flags that they support and not rely on the VFS masking unknown ones out: a
flag could be known to the VFS, yet not known to the filesystem.
Cc: David Howells <dhowells@redhat.com>
Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Synchronise the bpf.h header under tools, to report the fixes recently
brought to the documentation for the BPF helpers.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200511161536.29853-5-quentin@isovalent.com