35546 Commits

Author SHA1 Message Date
Eduard Zingerman
63bb645b9d selftests/bpf: Add notion of auxiliary programs for test_loader
In order to express test cases that use bpf_tail_call() intrinsic it
is necessary to have several programs to be loaded at a time.
This commit adds __auxiliary annotation to the set of annotations
supported by test_loader.c. Programs marked as auxiliary are always
loaded but are not treated as a separate test.

For example:

    void dummy_prog1(void);

    struct {
            __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
            __uint(max_entries, 4);
            __uint(key_size, sizeof(int));
            __array(values, void (void));
    } prog_map SEC(".maps") = {
            .values = {
                    [0] = (void *) &dummy_prog1,
            },
    };

    SEC("tc")
    __auxiliary
    __naked void dummy_prog1(void) {
            asm volatile ("r0 = 42; exit;");
    }

    SEC("tc")
    __description("reference tracking: check reference or tail call")
    __success __retval(0)
    __naked void check_reference_or_tail_call(void)
    {
            asm volatile (
            "r2 = %[prog_map] ll;"
            "r3 = 0;"
            "call %[bpf_tail_call];"
            "r0 = 0;"
            "exit;"
            :: __imm(bpf_tail_call),
            :  __clobber_all);
    }

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230421174234.2391278-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 12:16:56 -07:00
Florian Westphal
006c0e44ed selftests/bpf: add missing netfilter return value and ctx access tests
Extend prog_tests with two test cases:

 # ./test_progs --allow=verifier_netfilter_retcode
 #278/1   verifier_netfilter_retcode/bpf_exit with invalid return code. test1:OK
 #278/2   verifier_netfilter_retcode/bpf_exit with valid return code. test2:OK
 #278/3   verifier_netfilter_retcode/bpf_exit with valid return code. test3:OK
 #278/4   verifier_netfilter_retcode/bpf_exit with invalid return code. test4:OK
 #278     verifier_netfilter_retcode:OK

This checks that only accept and drop (0,1) are permitted.

NF_QUEUE could be implemented later if we can guarantee that attachment
of such programs can be rejected if they get attached to a pf/hook that
doesn't support async reinjection.

NF_STOLEN could be implemented via trusted helpers that can guarantee
that the skb will eventually be free'd.

v4: test case for bpf_nf_ctx access checks, requested by Alexei Starovoitov.
v5: also check ctx->{state,skb} can be dereferenced (Alexei).

 # ./test_progs --allow=verifier_netfilter_ctx
 #281/1   verifier_netfilter_ctx/netfilter invalid context access, size too short:OK
 #281/2   verifier_netfilter_ctx/netfilter invalid context access, size too short:OK
 #281/3   verifier_netfilter_ctx/netfilter invalid context access, past end of ctx:OK
 #281/4   verifier_netfilter_ctx/netfilter invalid context, write:OK
 #281/5   verifier_netfilter_ctx/netfilter valid context read and invalid write:OK
 #281/6   verifier_netfilter_ctx/netfilter test prog with skb and state read access:OK
 #281/7   verifier_netfilter_ctx/netfilter test prog with skb and state read access @unpriv:OK
 #281     verifier_netfilter_ctx:OK
Summary: 1/7 PASSED, 0 SKIPPED, 0 FAILED

This checks:
1/2: partial reads of ctx->{skb,state} are rejected
3. read access past sizeof(ctx) is rejected
4. write to ctx content, e.g. 'ctx->skb = NULL;' is rejected
5. ctx->state content cannot be altered
6. ctx->state and ctx->skb can be dereferenced
7. ... same program fails for unpriv (CAP_NET_ADMIN needed).

Link: https://lore.kernel.org/bpf/20230419021152.sjq4gttphzzy6b5f@dhcp-172-26-102-232.dhcp.thefacebook.com/
Link: https://lore.kernel.org/bpf/20230420201655.77kkgi3dh7fesoll@MacBook-Pro-6.local/
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-8-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:50 -07:00
Florian Westphal
d0fe92fb5e tools: bpftool: print netfilter link info
Dump protocol family, hook and priority value:
$ bpftool link
2: netfilter  prog 14
        ip input prio -128
        pids install(3264)
5: netfilter  prog 14
        ip6 forward prio 21
        pids a.out(3387)
9: netfilter  prog 14
        ip prerouting prio 123
        pids a.out(5700)
10: netfilter  prog 14
        ip input prio 21
        pids test2(5701)

v2: Quentin Monnet suggested to also add 'bpftool net' support:

$ bpftool net
xdp:

tc:

flow_dissector:

netfilter:

        ip prerouting prio 21 prog_id 14
        ip input prio -128 prog_id 14
        ip input prio 21 prog_id 14
        ip forward prio 21 prog_id 14
        ip output prio 21 prog_id 14
        ip postrouting prio 21 prog_id 14

'bpftool net' only dumps netfilter link type, links are sorted by protocol
family, hook and priority.

v5: fix bpf ci failure: libbpf needs small update to prog_type_name[]
    and probe_prog_load helper.
v4: don't fail with -EOPNOTSUPP in libbpf probe_prog_load, update
    prog_type_name[] with "netfilter" entry (bpf ci)
v3: fix bpf.h copy, 'reserved' member was removed (Alexei)
    use p_err, not fprintf (Quentin)

Suggested-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/eeeaac99-9053-90c2-aa33-cc1ecb1ae9ca@isovalent.com/
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-6-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:49 -07:00
Kui-Feng Lee
45cea721ea bpftool: Update doc to explain struct_ops register subcommand.
The "struct_ops register" subcommand now allows for an optional *LINK_DIR*
to be included. This specifies the directory path where bpftool will pin
struct_ops links with the same name as their corresponding map names.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230420002822.345222-2-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:10:10 -07:00
Kui-Feng Lee
0232b78897 bpftool: Register struct_ops with a link.
You can include an optional path after specifying the object name for the
'struct_ops register' subcommand.

Since the commit 226bc6ae6405 ("Merge branch 'Transit between BPF TCP
congestion controls.'") has been accepted, it is now possible to create a
link for a struct_ops. This can be done by defining a struct_ops in
SEC(".struct_ops.link") to make libbpf returns a real link. If we don't pin
the links before leaving bpftool, they will disappear. To instruct bpftool
to pin the links in a directory with the names of the maps, we need to
provide the path of that directory.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230420002822.345222-1-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:10:10 -07:00
Stanislav Fomichev
833d67ecdc selftests/bpf: Verify optval=NULL case
Make sure we get optlen exported instead of getting EFAULT.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230418225343.553806-3-sdf@google.com
2023-04-21 17:10:34 +02:00
Magnus Karlsson
02e93e0475 selftests/xsk: Put MAP_HUGE_2MB in correct argument
Put the flag MAP_HUGE_2MB in the correct flags argument instead of the
wrong offset argument.

Fixes: 2ddade322925 ("selftests/xsk: Fix munmap for hugepage allocated umem")
Reported-by: Kal Cutter Conley <kal.conley@dectris.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230421062208.3772-1-magnus.karlsson@gmail.com
2023-04-21 16:35:10 +02:00
Dave Marchevsky
4ab07209d5 bpf: Fix bpf_refcount_acquire's refcount_t address calculation
When calculating the address of the refcount_t struct within a local
kptr, bpf_refcount_acquire_impl should add refcount_off bytes to the
address of the local kptr. Due to some missing parens, the function is
incorrectly adding sizeof(refcount_t) * refcount_off bytes. This patch
fixes the calculation.

Due to the incorrect calculation, bpf_refcount_acquire_impl was trying
to refcount_inc some memory well past the end of local kptrs, resulting
in kasan and refcount complaints, as reported in [0]. In that thread,
Florian and Eduard discovered that bpf selftests written in the new
style - with __success and an expected __retval, specifically - were
not actually being run. As a result, selftests added in bpf_refcount
series weren't really exercising this behavior, and thus didn't unearth
the bug.

With this fixed behavior it's safe to revert commit 7c4b96c00043
("selftests/bpf: disable program test run for progs/refcounted_kptr.c"),
this patch does so.

  [0] https://lore.kernel.org/bpf/ZEEp+j22imoN6rn9@strlen.de/

Fixes: 7c50b1cb76ac ("bpf: Add bpf_refcount_acquire kfunc")
Reported-by: Florian Westphal <fw@strlen.de>
Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20230421074431.3548349-1-davemarchevsky@fb.com
2023-04-21 16:31:37 +02:00
Marc Zyngier
6dcf7316e0 Merge branch kvm-arm64/smccc-filtering into kvmarm-master/next
* kvm-arm64/smccc-filtering:
  : .
  : SMCCC call filtering and forwarding to userspace, courtesy of
  : Oliver Upton. From the cover letter:
  :
  : "The Arm SMCCC is rather prescriptive in regards to the allocation of
  : SMCCC function ID ranges. Many of the hypercall ranges have an
  : associated specification from Arm (FF-A, PSCI, SDEI, etc.) with some
  : room for vendor-specific implementations.
  :
  : The ever-expanding SMCCC surface leaves a lot of work within KVM for
  : providing new features. Furthermore, KVM implements its own
  : vendor-specific ABI, with little room for other implementations (like
  : Hyper-V, for example). Rather than cramming it all into the kernel we
  : should provide a way for userspace to handle hypercalls."
  : .
  KVM: selftests: Fix spelling mistake "KVM_HYPERCAL_EXIT_SMC" -> "KVM_HYPERCALL_EXIT_SMC"
  KVM: arm64: Test that SMC64 arch calls are reserved
  KVM: arm64: Prevent userspace from handling SMC64 arch range
  KVM: arm64: Expose SMC/HVC width to userspace
  KVM: selftests: Add test for SMCCC filter
  KVM: selftests: Add a helper for SMCCC calls with SMC instruction
  KVM: arm64: Let errors from SMCCC emulation to reach userspace
  KVM: arm64: Return NOT_SUPPORTED to guest for unknown PSCI version
  KVM: arm64: Introduce support for userspace SMCCC filtering
  KVM: arm64: Add support for KVM_EXIT_HYPERCALL
  KVM: arm64: Use a maple tree to represent the SMCCC filter
  KVM: arm64: Refactor hvc filtering to support different actions
  KVM: arm64: Start handling SMCs from EL1
  KVM: arm64: Rename SMC/HVC call handler to reflect reality
  KVM: arm64: Add vm fd device attribute accessors
  KVM: arm64: Add a helper to check if a VM has ran once
  KVM: x86: Redefine 'longmode' as a flag for KVM_EXIT_HYPERCALL

Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-04-21 09:44:32 +01:00
Marc Zyngier
367eb095b8 Merge branch kvm-arm64/selftest/misc-6.4 into kvmarm-master/next
* kvm-arm64/selftest/misc-6.4:
  : .
  : Misc selftest updates for 6.4
  :
  : - Add comments for recently added ID registers
  : .
  KVM: selftests: Comment newly defined aarch64 ID registers

Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-04-21 09:39:07 +01:00
Marc Zyngier
e2e321a7d6 Merge branch kvm-arm64/selftest/lpa into kvmarm-master/next
* kvm-arm64/selftest/lpa:
  : .
  : Selftest fixes addressing PTE and TTBR0_EL1 encodings for
  : 52bit PAs
  : .
  KVM: selftests: arm64: Fix ttbr0_el1 encoding for PA bits > 48
  KVM: selftests: arm64: Fix pte encode/decode for PA bits > 48
  KVM: selftests: Fixup config fragment for access_tracking_perf_test

Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-04-21 09:37:36 +01:00
Marc Zyngier
b22498c484 Merge branch kvm-arm64/timer-vm-offsets into kvmarm-master/next
* kvm-arm64/timer-vm-offsets: (21 commits)
  : .
  : This series aims at satisfying multiple goals:
  :
  : - allow a VMM to atomically restore a timer offset for a whole VM
  :   instead of updating the offset each time a vcpu get its counter
  :   written
  :
  : - allow a VMM to save/restore the physical timer context, something
  :   that we cannot do at the moment due to the lack of offsetting
  :
  : - provide a framework that is suitable for NV support, where we get
  :   both global and per timer, per vcpu offsetting, and manage
  :   interrupts in a less braindead way.
  :
  : Conflict resolution involves using the new per-vcpu config lock instead
  : of the home-grown timer lock.
  : .
  KVM: arm64: Handle 32bit CNTPCTSS traps
  KVM: arm64: selftests: Augment existing timer test to handle variable offset
  KVM: arm64: selftests: Deal with spurious timer interrupts
  KVM: arm64: selftests: Add physical timer registers to the sysreg list
  KVM: arm64: nv: timers: Support hyp timer emulation
  KVM: arm64: nv: timers: Add a per-timer, per-vcpu offset
  KVM: arm64: Document KVM_ARM_SET_CNT_OFFSETS and co
  KVM: arm64: timers: Abstract the number of valid timers per vcpu
  KVM: arm64: timers: Fast-track CNTPCT_EL0 trap handling
  KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor
  KVM: arm64: timers: Move the timer IRQs into arch_timer_vm_data
  KVM: arm64: timers: Abstract per-timer IRQ access
  KVM: arm64: timers: Rationalise per-vcpu timer init
  KVM: arm64: timers: Allow save/restoring of the physical timer
  KVM: arm64: timers: Allow userspace to set the global counter offset
  KVM: arm64: Expose {un,}lock_all_vcpus() to the rest of KVM
  KVM: arm64: timers: Allow physical offset without CNTPOFF_EL2
  KVM: arm64: timers: Use CNTPOFF_EL2 to offset the physical timer
  arm64: Add HAS_ECV_CNTPOFF capability
  arm64: Add CNTPOFF_EL2 register definition
  ...

Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-04-21 09:36:40 +01:00
Ido Schimmel
7648ac72dc selftests: net: Add bridge neighbor suppression test
Add test cases for bridge neighbor suppression, testing both per-port
and per-{Port, VLAN} neighbor suppression with both ARP and NS packets.

Example truncated output:

 # ./test_bridge_neigh_suppress.sh
 [...]
 Tests passed: 148
 Tests failed:   0

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21 08:25:50 +01:00
Shunsuke Mie
e9c4962c5d tools/virtio: fix build caused by virtio_ring changes
Fix the build dependency for virtio_test. The virtio_ring that is used from
the test requires container_of_const(). Change to use container_of.h kernel
header directly and adapt related codes.

Signed-off-by: Shunsuke Mie <mie@igel.co.jp>
Message-Id: <20230417022037.917668-2-mie@igel.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:35 -04:00
Rong Tao
6b27cd84a7 tools/virtio: virtio_test -h,--help should return directly
When we get help information, we should return directly, and we should not
execute test cases. Move the exit() directly into the help() function and
remove it from case '?'.

Signed-off-by: Rong Tao <rongtao@cestc.cn>
Message-Id: <tencent_822CEBEB925205EA1573541CD1C2604F4805@qq.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:30 -04:00
Rong Tao
9b2b3de63c tools/virtio: virtio_test: Fix indentation
Replace eight spaces with Tab.

Signed-off-by: Rong Tao <rtoax@foxmail.com>
Message-Id: <tencent_89579C514BC4020324A1A4ACA44B5B95BB07@qq.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:30 -04:00
Vladimir Oltean
e6991384ac selftests: forwarding: add a test for MAC Merge layer
The MAC Merge layer (IEEE 802.3-2018 clause 99) does all the heavy
lifting for Frame Preemption (IEEE 802.1Q-2018 clause 6.7.2), a TSN
feature for minimizing latency.

Preemptible traffic is different on the wire from normal traffic in
incompatible ways. If we send a preemptible packet and the link partner
doesn't support preemption, it will drop it as an error frame and we
will never know. The MAC Merge layer has a control plane of its own,
which can be manipulated (using ethtool) in order to negotiate this
capability with the link partner (through LLDP).

Actually the TLV format for LLDP solves this problem only partly,
because both partners only advertise:
- if they support preemption (RX and TX)
- if they have enabled preemption (TX)
so we cannot tell the link partner what to do - we cannot force it to
enable reception of our preemptible packets.

That is fully solved by the verification feature, where the local device
generates some small probe frames which look like preemptible frames
with no useful content, and the link partner is obliged to respond to
them if it supports the standard. If the verification times out, we know
that preemption isn't active in our TX direction on the link.

Having clarified the definition, this selftest exercises the manual
(ethtool) configuration path of 2 link partners (with and without
verification), and the LLDP code path, using the openlldp project.

The test also verifies the TX activity of the MAC Merge layer by
sending traffic through a traffic class configured as preemptible
(using mqprio). There isn't a good way to make this really portable
(user space cannot find out how many traffic classes there are for
a device), but I chose num_tc 4 here, that should work reasonably well.
I also know that some devices (stmmac) only permit TXQ0 to be
preemptible, so this is why PREEMPTIBLE_PRIO was strategically chosen
as 0. Even if other hardware is more configurable, this test should
cover the baseline.

This is not really a "forwarding" selftest, but I put it near the other
"ethtool" selftests.

$ ./ethtool_mm.sh eno0 swp0
TEST: Manual configuration with verification: eno0 to swp0          [ OK ]
TEST: Manual configuration with verification: swp0 to eno0          [ OK ]
TEST: Manual configuration without verification: eno0 to swp0       [ OK ]
TEST: Manual configuration without verification: swp0 to eno0       [ OK ]
TEST: Manual configuration with failed verification: eno0 to swp0   [ OK ]
TEST: Manual configuration with failed verification: swp0 to eno0   [ OK ]
TEST: LLDP                                                          [ OK ]

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 20:03:21 -07:00
Vladimir Oltean
b5bf7126a6 selftests: forwarding: introduce helper for standard ethtool counters
Counters for the MAC Merge layer and preemptible MAC have standardized
so far on using structured ethtool stats as opposed to the driver
specific names and meanings.

Benefit from that rare opportunity and introduce a helper to lib.sh for
querying standardized counters, in the hope that these will take off for
other uses as well.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 20:03:21 -07:00
Petr Machata
8fcac79270 selftests: forwarding: generalize bail_on_lldpad from mlxsw
mlxsw selftests often invoke a bail_on_lldpad() helper to make sure LLDPAD
is not running, to prevent conflicts between the QoS configuration applied
through TC or DCB command line tool, and the DCB configuration that LLDPAD
might apply. This helper might be useful to others. Move the function to
lib.sh, and parameterize to make reusable in other contexts.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 20:03:21 -07:00
Petr Machata
54e906f163 selftests: forwarding: sch_tbf_*: Add a pre-run hook
The driver-specific wrappers of these selftests invoke bail_on_lldpad to
make sure that LLDPAD doesn't trample the configuration. The function
bail_on_lldpad is going to move to lib.sh in the next patch. With that, it
won't be visible for the wrappers before sourcing the framework script. And
after sourcing it, it is too late: the selftest will have run by then.

One option might be to source NUM_NETIFS=0 lib.sh from the wrapper, but
even if that worked (it might, it might not), that seems cumbersome. lib.sh
is doing fair amount of stuff, and even if it works today, it does not look
particularly solid as a solution.

Instead, introduce a hook, sch_tbf_pre_hook(), that when available, gets
invoked. Move the bail to the hook.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 20:03:21 -07:00
Eduard Zingerman
cbb110bc66 selftests/bpf: populate map_array_ro map for verifier_array_access test
Two test cases:
- "valid read map access into a read-only array 1" and
- "valid read map access into a read-only array 2"

Expect that map_array_ro map is filled with mock data. This logic was
not taken into acount during initial test conversion.

This commit modifies prog_tests/verifier.c entry point for this test
to fill the map.

Fixes: a3c830ae0209 ("selftests/bpf: verifier/array_access.c converted to inline assembly")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230420232317.2181776-5-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-20 16:49:16 -07:00
Eduard Zingerman
5b22f4d143 selftests/bpf: add pre bpf_prog_test_run_opts() callback for test_loader
When a test case is annotated with __retval tag the test_loader engine
would use libbpf's bpf_prog_test_run_opts() to do a test run of the
program and compare retvals.

This commit allows to perform arbitrary actions on bpf object right
before test loader invokes bpf_prog_test_run_opts(). This could be
used to setup some state for program execution, e.g. fill some maps.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230420232317.2181776-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-20 16:49:16 -07:00
Eduard Zingerman
7cdddb99e4 selftests/bpf: fix __retval() being always ignored
Florian Westphal found a bug in and suggested a fix for test_loader.c
processing of __retval tag. Because of this bug the function
test_loader.c:do_prog_test_run() never executed and all __retval test
tags were ignored.

If this bug is fixed a number of test cases from
progs/verifier_array_access.c fail with retval not matching the
expected value. This test was recently converted to use test_loader.c
and inline assembly in [1]. When doing the conversion I missed the
important detail of test_verifier.c operation: when it creates
fixup_map_array_ro, fixup_map_array_wo and fixup_map_array_small it
populates these maps with a dummy record.

Disabling the __retval checks for the affected verifier_array_access
in this commit to avoid false-postivies in any potential bisects.
The issue is addressed in the next patch.

I verified that the __retval tags are now respected by changing
expected return values for all tests annotated with __retval, and
checking that these tests started to fail.

[1] https://lore.kernel.org/bpf/20230325025524.144043-1-eddyz87@gmail.com/

Fixes: 19a8e06f5f91 ("selftests/bpf: Tests execution support for test_loader.c")
Reported-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/bpf/f4c4aee644425842ee6aa8edf1da68f0a8260e7c.camel@gmail.com/T/
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230420232317.2181776-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-20 16:49:16 -07:00
Eduard Zingerman
7c4b96c000 selftests/bpf: disable program test run for progs/refcounted_kptr.c
Florian Westphal found a bug in test_loader.c processing of __retval
tag. Because of this bug the function test_loader.c:do_prog_test_run()
never executed and all __retval test tags were ignored. This hid an
issue with progs/refcounted_kptr.c tests.

When __retval tag bug is fixed and refcounted_kptr.c tests are run
kernel reports various issues and eventually hangs. Shortest reproducer
is the following command run a few times:

  $ for i in $(seq 1 4); do (./test_progs --allow=refcounted_kptr &); done

Commenting out __retval tags for these tests until this issue is resolved.

Reported-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/bpf/f4c4aee644425842ee6aa8edf1da68f0a8260e7c.camel@gmail.com/T/
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230420232317.2181776-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-20 16:49:16 -07:00
Quentin Monnet
4b7ef71ac9 bpftool: Replace "__fallthrough" by a comment to address merge conflict
The recent support for inline annotations in control flow graphs
generated by bpftool introduced the usage of the "__fallthrough" macro
in a switch/case block in btf_dumper.c. This change went through the
bpf-next tree, but resulted in a merge conflict in linux-next, because
this macro has been renamed "fallthrough" (no underscores) in the
meantime.

To address the conflict, we temporarily switch to a simple comment
instead of a macro.

Related: commit f7a858bffcdd ("tools: Rename __fallthrough to fallthrough")

Fixes: 9fd496848b1c ("bpftool: Support inline annotations when dumping the CFG of a program")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/all/yt9dttxlwal7.fsf@linux.ibm.com/
Link: https://lore.kernel.org/bpf/20230412123636.2358949-1-tmricht@linux.ibm.com/
Link: https://lore.kernel.org/bpf/20230420003333.90901-1-quentin@isovalent.com
2023-04-20 16:38:10 -07:00
Jakub Kicinski
681c5b51dc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Adjacent changes:

net/mptcp/protocol.h
  63740448a32e ("mptcp: fix accept vs worker race")
  2a6a870e44dd ("mptcp: stops worker on unaccepted sockets at listener close")
  ddb1a072f858 ("mptcp: move first subflow allocation at mpc access time")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 16:29:51 -07:00
Ian Rogers
9be6ab181b libperf rc_check: Enable implicitly with sanitizers
If using leak sanitizer then implicitly enable reference count checking.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230420171812.561603-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-20 15:12:02 -03:00
Ian Rogers
edd4cab2d4 perf test: Fix maps use after put
Fix a use after put reference count issue. maps is copied from leader,
but the leader is put on line 79 and then maps is used to read the
reference count below - so a use after put, with the put of maps
happening within thread__put. Fix by reversing the order of puts so
that the leader is put last.

To explain the reference count checker, I wrote this up as a little
example here:
https://perf.wiki.kernel.org/index.php/Reference_Count_Checking

Note, the bug was introduced by the committer and wasn't present in
the original reference count patch set.

Committer notes:

Yes, the bug predated your patch and is detected by the reference count
checking you contributed.

This was just part of splitting up your series into smaller chunks, in
this case either we fix the problem detected while developing this
reference counting infrastructure before the patch introducing REFCNT_CHECKING
or fix it later after the merged infrastructure, when built with
EXTRA_CFLAGS="-DREFCNT_CHECKING=1" detects it when running 'perf test', which
is what this patch does.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20230420030430.489243-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-20 08:23:52 -03:00
Feng Zhou
5ff54dedf3 selftests/bpf: Add test to access integer type of variable array
Add prog test for accessing integer type of variable array in tracing
program.
In addition, hook load_balance function to access sd->span[0], only
to confirm whether the load is successful. Because there is no direct
way to trigger load_balance call.

Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com>
Link: https://lore.kernel.org/r/20230420032735.27760-3-zhoufeng.zf@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-19 21:29:39 -07:00
Benjamin Gray
ae7312c090 selftests/powerpc/dscr: Restore timeout to DSCR selftests
Reducing the time taken by dscr_sysfs_test.c allows restoring the
default timeout, which was removed in
commit 850507f30c38 ("selftests/powerpc: Turn off timeout setting for
benchmarks, dscr, signal, tm") because that test took too long.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-8-bgray@linux.ibm.com
2023-04-20 13:21:46 +10:00
Benjamin Gray
c14a9d0a79 selftests/powerpc/dscr: Speed up DSCR sysfs tests
This test case is extremely slow, taking around a minute compared to
most of the other DSCR tests taking a second at most. Perf shows most
time is spent by the kernel switching to each CPU it reads in
/sys/devices/system/cpu. This switching is an unavoidable consequnce
of reading all the .../cpuN/dscr values.

Remove the outer iteration loop from this test case, reducing the reads
from 1600 to 16. This still updates the DSCR 16 times and verifies on
every CPU each time, so I do not expect the lower coverage to be
meaningful. The speedup is significant: back down to ~1 second like the
other tests.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-7-bgray@linux.ibm.com
2023-04-20 13:21:46 +10:00
Benjamin Gray
3067b89ab6 selftests/powerpc/dscr: Improve DSCR explicit random test case
The tests currently have a single writer thread updating the system
DSCR with a 1/1000 chance looped only 100 times. So only around one in
10 runs actually do anything.

* Add multiple threads to the dscr_explicit_random_test case.
* Use a barrier to make all the threads start work as simultaneously as
  possible.
* Use a rwlock and make all threads have a reasonable chance to write to
  the DSCR on each iteration.
  PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP is used to prevent
  writers from starving while all the other threads keep reading.
  Logging the reads/writes shows a decent mix across the whole test.
* Allow all threads a chance to write.
* Make the chance of writing more likely.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-6-bgray@linux.ibm.com
2023-04-20 13:21:45 +10:00
Benjamin Gray
fda8158870 selftests/powerpc/dscr: Add lockstep test cases to DSCR explicit tests
Add new cases to the relevant tests that use explicitly synchronized
threads to test the behaviour across context switches with less
randomness. By locking the participants to the same CPU we guarantee a
context switch occurs each time they make progress, which is a likely
failure point if the kernel is not tracking the thread local DSCR
correctly.

The random case is left in to keep exercising potential edge cases.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-5-bgray@linux.ibm.com
2023-04-20 13:21:45 +10:00
Benjamin Gray
6ff4dc2548 selftests/powerpc: Allow bind_to_cpu() to automatically pick CPU
All current users of bind_to_cpu() don't care _which_ CPU they get, just
that they are bound to a single free one. So alter the interface to

	1. Accept a BIND_CPU_ANY value that tells it to automatically
	   pick a CPU
	2. Return the picked CPU

And convert all these users to bind_to_cpu(BIND_CPU_ANY).

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-4-bgray@linux.ibm.com
2023-04-20 13:21:45 +10:00
Benjamin Gray
c97b2fc662 selftests/powerpc: Move bind_to_cpu() to utils.h
This function will be useful in the DSCR test patches later in this
series, so promote it to be shared by all powerpc selftests.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-3-bgray@linux.ibm.com
2023-04-20 13:21:45 +10:00
Benjamin Gray
15f0c2601e selftests/powerpc/dscr: Correct typos
Correct a couple of typos while working on other improvements to the
DSCR tests.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406043320.125138-2-bgray@linux.ibm.com
2023-04-20 13:21:45 +10:00
Nicholas Piggin
4e991e3c16 powerpc: add CFUNC assembly label annotation
This macro is to be used in assembly where C functions are called.
pcrel addressing mode requires branches to functions with a
localentry value of 1 to have either a trailing nop or @notoc.
This macro permits the latter without changing callers.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add dummy definitions to fix selftests build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-5-npiggin@gmail.com
2023-04-20 12:54:24 +10:00
Linus Torvalds
cb0856346a 22 hotfixes.
19 are cc:stable and the remainder address issues which were introduced
 during this merge cycle, or aren't considered suitable for -stable
 backporting.
 
 19 are for MM and the remainder are for other subsystems.
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Merge tag 'mm-hotfixes-stable-2023-04-19-16-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "22 hotfixes.

  19 are cc:stable and the remainder address issues which were
  introduced during this merge cycle, or aren't considered suitable for
  -stable backporting.

  19 are for MM and the remainder are for other subsystems"

* tag 'mm-hotfixes-stable-2023-04-19-16-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
  nilfs2: initialize unused bytes in segment summary blocks
  mm: page_alloc: skip regions with hugetlbfs pages when allocating 1G pages
  mm/mmap: regression fix for unmapped_area{_topdown}
  maple_tree: fix mas_empty_area() search
  maple_tree: make maple state reusable after mas_empty_area_rev()
  mm: kmsan: handle alloc failures in kmsan_ioremap_page_range()
  mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush()
  tools/Makefile: do missed s/vm/mm/
  mm: fix memory leak on mm_init error handling
  mm/page_alloc: fix potential deadlock on zonelist_update_seq seqlock
  kernel/sys.c: fix and improve control flow in __sys_setres[ug]id()
  Revert "userfaultfd: don't fail on unrecognized features"
  writeback, cgroup: fix null-ptr-deref write in bdi_split_work_to_wbs
  maple_tree: fix a potential memory leak, OOB access, or other unpredictable bug
  tools/mm/page_owner_sort.c: fix TGID output when cull=tg is used
  mailmap: update jtoppins' entry to reference correct email
  mm/mempolicy: fix use-after-free of VMA iterator
  mm/huge_memory.c: warn with pr_warn_ratelimited instead of VM_WARN_ON_ONCE_FOLIO
  mm/mprotect: fix do_mprotect_pkey() return on error
  mm/khugepaged: check again on anon uffd-wp during isolation
  ...
2023-04-19 17:55:45 -07:00
Arnaldo Carvalho de Melo
265b0de2f0 perf probe: Add missing 0x prefix for addresses printed in hexadecimal
To fix this confusing warning:

  # perf probe -l
  Failed to find debug information for address 798240
    probe_main:prometheus_new_counter__return (on github.com/prometheus/client_golang/prometheus.NewCounter%return in /home/acme/git/prometheus-uprobes/main with counter)
  #

As that 798240 is printed with PRIx64 but has no letters, better print
the 0x prefix to disambiguate.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZEBCyFu2GjTw6qOi@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 16:38:43 -03:00
Arnaldo Carvalho de Melo
686c511866 perf build: Test the refcnt check build
Make sure we test build the currently added REFCNT_CHECKING
infrastructure.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 13:47:03 -03:00
Ian Rogers
2832ef81d4 perf map: Add reference count checking
There's no strict get/put policy with map that leads to leaks or use
after free. Reference count checking identifies correct pairing of gets
and puts.

Committer notes:

Extracted from a larger patch removing bits that were covered by the use
of pre-existing map__ accessors (e.g. maps__nr_maps()) and new ones
added (map__refcnt() and the maps__set_ ones) to reduce
RC_CHK_ACCESS(maps)-> source code pollution.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Link: https://lore.kernel.org/lkml/20230407230405.2931830-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 12:57:53 -03:00
Arnaldo Carvalho de Melo
e6a9efcee5 perf map: Add set_ methods for map->{start,end,pgoff,pgoff,reloc,erange_warned,dso,map_ip,unmap_ip,priv}
To have a way to intercept usage of the reference counted struct map.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 12:54:41 -03:00
Arnaldo Carvalho de Melo
e1805aae1e perf map: Add missing conversions to map__refcnt()
Some conversions weren't performed in 4e8db2d7520f780f ("perf map: Add
map__refcnt() accessor to use in the maps test"), fix it.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 12:33:53 -03:00
Magnus Karlsson
2ddade3229 selftests/xsk: Fix munmap for hugepage allocated umem
Fix the unmapping of hugepage allocated umems so that they are
properly unmapped. The new test referred to in the fixes label,
introduced a test that allocated a umem that is not a multiple of a 2M
hugepage size. This is fine for mmap() that rounds the size up the
nearest multiple of 2M. But munmap() requires the size to be a
multiple of the hugepage size in order for it to unmap the region. The
current behaviour of not properly unmapping the umem, was discovered
when further additions of tests that require hugepages (unaligned mode
tests only) started failing as the system was running out of
hugepages.

Fixes: c0801598e543 ("selftests: xsk: Add test UNALIGNED_INV_DESC_4K1_FRAME_SIZE")
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230418143617.27762-1-magnus.karlsson@gmail.com
2023-04-19 16:33:53 +02:00
Ian Rogers
8f12692b7e perf maps: Add reference count checking
Add reference count checking to make sure of good use of get and put.
Add and use accessors to reduce RC_CHK clutter.

The only significant issue was in tests/thread-maps-share.c where
reference counts were released in the reverse order to acquisition,
leading to a use after put. This was fixed by reversing the put order.

Committer notes:

Extracted from a larger patch removing bits that were covered by the use
of pre-existing maps__ accessors (e.g. maps__nr_maps()) and new ones
added (maps__refcnt()) to reduce RC_CHK_ACCESS(maps)-> source code
pollution.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Link: https://lore.kernel.org/lkml/20230407230405.2931830-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 10:53:01 -03:00
Arnaldo Carvalho de Melo
a07dacad8a perf maps: Use maps__nr_maps() instead of open coded maps->nr_maps
To use the existing accessor and be consistent.

Signef-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 10:52:54 -03:00
Arnaldo Carvalho de Melo
fe693d951e perf maps: Add maps__refcnt() accessor to allow checking maps pointer
To remove one more direct access to 'struct maps' so that we can
intercept accesses to its instantiations and refcount check it to catch
use after free, etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 10:52:54 -03:00
Arnaldo Carvalho de Melo
3ad1be6fae perf dso: Fix use before NULL check introduced by map__dso() introduction
James Clark noticed that the recent 63df0e4bc368adbd ("perf map: Add
accessor for dso") patch accessed map->dso before the 'map' variable was
NULL checked, which is a change in logic that leads to segmentation
faults, so comb thru that patch to fix similar cases.

Fixes: 63df0e4bc368adbd ("perf map: Add accessor for dso")
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/lkml/ZD68RYCVT8hqPuxr@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-19 10:51:48 -03:00
Tiezhu Yang
b5533e990d tools/loongarch: Use __SIZEOF_LONG__ to define __BITS_PER_LONG
Although __SIZEOF_POINTER__ is equal to _SIZEOF_LONG__ on LoongArch,
it is better to use __SIZEOF_LONG__ to define __BITS_PER_LONG to keep
consistent between arch/loongarch/include/uapi/asm/bitsperlong.h and
tools/arch/loongarch/include/uapi/asm/bitsperlong.h.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-04-19 12:07:34 +08:00
Linus Torvalds
427fda2c8a x86: improve on the non-rep 'copy_user' function
The old 'copy_user_generic_unrolled' function was oddly implemented for
largely historical reasons: it had been largely based on the uncached
copy case, which has some other concerns.

For example, the __copy_user_nocache() function uses 'movnti' for the
destination stores, and those want the destination to be aligned.  In
contrast, the regular copy function doesn't really care, and trying to
align things only complicates matters.

Also, like the clear_user function, the copy function had some odd
handling of the repeat counts, complicating the exception handling for
no really good reason.  So as with clear_user, just write it to keep all
the byte counts in the %rcx register, exactly like the 'rep movs'
functionality that this replaces.

Unlike a real 'rep movs', we do allow for this to trash a few temporary
registers to not have to unnecessarily save/restore registers on the
stack.

And like the clearing case, rename this to what it now clearly is:
'rep_movs_alternative', and make it one coherent function, so that it
shows up as such in profiles (instead of the odd split between
"copy_user_generic_unrolled" and "copy_user_short_string", the latter of
which was not about strings at all, and which was shared with the
uncached case).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-04-18 17:05:28 -07:00