36557 Commits

Author SHA1 Message Date
Marc Zyngier
d22558dd0a irqdomain: Introduce irq_resolve_mapping()
Rework irq_find_mapping() to return an both an irq_desc pointer,
optionally the virtual irq number, and rename the result to
__irq_resolve_mapping(). a new helper called irq_resolve_mapping()
is provided for code that doesn't need the virtual irq number.

irq_find_mapping() is also rewritten in terms of __irq_resolve_mapping().

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:18 +01:00
Marc Zyngier
d4a45c68dc irqdomain: Protect the linear revmap with RCU
It is pretty odd that the radix tree uses RCU while the linear
portion doesn't, leading to potential surprises for the users,
depending on how the irqdomain has been created.

Fix this by moving the update of the linear revmap under
the mutex, and the lookup under the RCU read-side lock.

The mutex name is updated to reflect that it doesn't only
cover the radix-tree anymore.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:18 +01:00
Marc Zyngier
48b15a7921 irqdomain: Cache irq_data instead of a virq number in the revmap
Caching a virq number in the revmap is pretty inefficient, as
it means we will need to convert it back to either an irq_data
or irq_desc to do anything with it.

It is also a bit odd, as the radix tree does cache irq_data
pointers.

Change the revmap type to be an irq_data pointer instead of
an unsigned int, and preserve the current API for now.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:18 +01:00
Marc Zyngier
426fa31614 irqdomain: Use struct_size() helper when allocating irqdomain
Instead of open-coding the size computation of struct irqdomain,
use the struct_size() helper instead.

This is going to be handy as we change the type of the revmap
array.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:17 +01:00
Marc Zyngier
4f86a06e2d irqdomain: Make normal and nomap irqdomains exclusive
Direct mappings are completely exclusive of normal mappings, meaning
that we can refactor the code slightly so that we can get rid of
the revmap_direct_max_irq field and use the revmap_size field
instead, reducing the size of the irqdomain structure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:17 +01:00
Marc Zyngier
e37af8011a powerpc: Move the use of irq_domain_add_nomap() behind a config option
Only a handful of old PPC systems are still using the old 'nomap'
variant of the irqdomain library. Move the associated definitions
behind a configuration option, which will allow us to make some
more radical changes.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:17 +01:00
Marc Zyngier
1da027362a irqdomain: Reimplement irq_linear_revmap() with irq_find_mapping()
irq_linear_revmap() is supposed to be a fast path for domain
lookups, but it only exposes low-level details of the irqdomain
implementation, details which are better kept private.

The *overhead* between the two is only a function call and
a couple of tests, so it is likely that noone can show any
meaningful difference compared to the cost of taking an
interrupt.

Reimplement irq_linear_revmap() with irq_find_mapping()
in order to preserve source code compatibility, and
rename the internal field for a measure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:17 +01:00
Peter Zijlstra
156172a13f irq_work: Make irq_work_queue() NMI-safe again
Someone carelessly put NMI unsafe code in irq_work_queue(), breaking
just about every single user. Also, someone has a terrible comment
style.

Fixes: e2b5bcf9f5ba ("irq_work: record irq_work_queue() call stack")
Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YL+uBq8LzXXZsYVf@hirez.programming.kicks-ass.net
2021-06-10 10:00:08 +02:00
Baokun Li
dd8b865cc4 audit: Use list_move instead of list_del/list_add
Using list_move() instead of list_del() + list_add().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-06-08 22:18:35 -04:00
Sergey Nazarov
619ed58ac4 audit: Rename enum audit_state constants to avoid AUDIT_DISABLED redefinition
AUDIT_DISABLED defined in kernel/audit.h as element of enum audit_state
and redefined in kernel/audit.c. This produces a warning when kernel builds
with syscalls audit disabled and brokes kernel build if -Werror used.
enum audit_state used in syscall audit code only. This patch changes
enum audit_state constants prefix AUDIT to AUDIT_STATE to avoid
AUDIT_DISABLED redefinition.

Signed-off-by: Sergey Nazarov <s-nazarov@yandex.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-06-08 22:05:24 -04:00
Jan Kara
11c7aa0dde rq-qos: fix missed wake-ups in rq_qos_throttle try two
Commit 545fbd0775ba ("rq-qos: fix missed wake-ups in rq_qos_throttle")
tried to fix a problem that a process could be sleeping in rq_qos_wait()
without anyone to wake it up. However the fix is not complete and the
following can still happen:

CPU1 (waiter1)		CPU2 (waiter2)		CPU3 (waker)
rq_qos_wait()		rq_qos_wait()
  acquire_inflight_cb() -> fails
			  acquire_inflight_cb() -> fails

						completes IOs, inflight
						  decreased
  prepare_to_wait_exclusive()
			  prepare_to_wait_exclusive()
  has_sleeper = !wq_has_single_sleeper() -> true as there are two sleepers
			  has_sleeper = !wq_has_single_sleeper() -> true
  io_schedule()		  io_schedule()

Deadlock as now there's nobody to wakeup the two waiters. The logic
automatically blocking when there are already sleepers is really subtle
and the only way to make it work reliably is that we check whether there
are some waiters in the queue when adding ourselves there. That way, we
are guaranteed that at least the first process to enter the wait queue
will recheck the waiting condition before going to sleep and thus
guarantee forward progress.

Fixes: 545fbd0775ba ("rq-qos: fix missed wake-ups in rq_qos_throttle")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210607112613.25344-1-jack@suse.cz
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-08 15:12:57 -06:00
Liangyan
3e08a9f976 tracing: Correct the length check which causes memory corruption
We've suffered from severe kernel crashes due to memory corruption on
our production environment, like,

Call Trace:
[1640542.554277] general protection fault: 0000 [#1] SMP PTI
[1640542.554856] CPU: 17 PID: 26996 Comm: python Kdump: loaded Tainted:G
[1640542.556629] RIP: 0010:kmem_cache_alloc+0x90/0x190
[1640542.559074] RSP: 0018:ffffb16faa597df8 EFLAGS: 00010286
[1640542.559587] RAX: 0000000000000000 RBX: 0000000000400200 RCX:
0000000006e931bf
[1640542.560323] RDX: 0000000006e931be RSI: 0000000000400200 RDI:
ffff9a45ff004300
[1640542.560996] RBP: 0000000000400200 R08: 0000000000023420 R09:
0000000000000000
[1640542.561670] R10: 0000000000000000 R11: 0000000000000000 R12:
ffffffff9a20608d
[1640542.562366] R13: ffff9a45ff004300 R14: ffff9a45ff004300 R15:
696c662f65636976
[1640542.563128] FS:  00007f45d7c6f740(0000) GS:ffff9a45ff840000(0000)
knlGS:0000000000000000
[1640542.563937] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1640542.564557] CR2: 00007f45d71311a0 CR3: 000000189d63e004 CR4:
00000000003606e0
[1640542.565279] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[1640542.566069] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[1640542.566742] Call Trace:
[1640542.567009]  anon_vma_clone+0x5d/0x170
[1640542.567417]  __split_vma+0x91/0x1a0
[1640542.567777]  do_munmap+0x2c6/0x320
[1640542.568128]  vm_munmap+0x54/0x70
[1640542.569990]  __x64_sys_munmap+0x22/0x30
[1640542.572005]  do_syscall_64+0x5b/0x1b0
[1640542.573724]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[1640542.575642] RIP: 0033:0x7f45d6e61e27

James Wang has reproduced it stably on the latest 4.19 LTS.
After some debugging, we finally proved that it's due to ftrace
buffer out-of-bound access using a debug tool as follows:
[   86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000
[   86.780806]  no_context+0xdf/0x3c0
[   86.784327]  __do_page_fault+0x252/0x470
[   86.788367]  do_page_fault+0x32/0x140
[   86.792145]  page_fault+0x1e/0x30
[   86.795576]  strncpy_from_unsafe+0x66/0xb0
[   86.799789]  fetch_memory_string+0x25/0x40
[   86.804002]  fetch_deref_string+0x51/0x60
[   86.808134]  kprobe_trace_func+0x32d/0x3a0
[   86.812347]  kprobe_dispatcher+0x45/0x50
[   86.816385]  kprobe_ftrace_handler+0x90/0xf0
[   86.820779]  ftrace_ops_assist_func+0xa1/0x140
[   86.825340]  0xffffffffc00750bf
[   86.828603]  do_sys_open+0x5/0x1f0
[   86.832124]  do_syscall_64+0x5b/0x1b0
[   86.835900]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

commit b220c049d519 ("tracing: Check length before giving out
the filter buffer") adds length check to protect trace data
overflow introduced in 0fc1b09ff1ff, seems that this fix can't prevent
overflow entirely, the length check should also take the sizeof
entry->array[0] into account, since this array[0] is filled the
length of trace data and occupy addtional space and risk overflow.

Link: https://lkml.kernel.org/r/20210607125734.1770447-1-liangyan.peng@linux.alibaba.com

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Xunlei Pang <xlpang@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: b220c049d519 ("tracing: Check length before giving out the filter buffer")
Reviewed-by: Xunlei Pang <xlpang@linux.alibaba.com>
Reviewed-by: yinbinbin <yinbinbin@alibabacloud.com>
Reviewed-by: Wetp Zhang <wetp.zy@linux.alibaba.com>
Tested-by: James Wang <jnwang@linux.alibaba.com>
Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-08 16:44:00 -04:00
Steven Rostedt (VMware)
6c14133d2d ftrace: Do not blindly read the ip address in ftrace_bug()
It was reported that a bug on arm64 caused a bad ip address to be used for
updating into a nop in ftrace_init(), but the error path (rightfully)
returned -EINVAL and not -EFAULT, as the bug caused more than one error to
occur. But because -EINVAL was returned, the ftrace_bug() tried to report
what was at the location of the ip address, and read it directly. This
caused the machine to panic, as the ip was not pointing to a valid memory
address.

Instead, read the ip address with copy_from_kernel_nofault() to safely
access the memory, and if it faults, report that the address faulted,
otherwise report what was in that location.

Link: https://lore.kernel.org/lkml/20210607032329.28671-1-mark-pk.tsai@mediatek.com/

Cc: stable@vger.kernel.org
Fixes: 05736a427f7e1 ("ftrace: warn on failure to disable mcount callers")
Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-08 16:44:00 -04:00
Suren Baghdasaryan
3958e2d0c3 cgroup: make per-cgroup pressure stall tracking configurable
PSI accounts stalls for each cgroup separately and aggregates it at each
level of the hierarchy. This causes additional overhead with psi_avgs_work
being called for each cgroup in the hierarchy. psi_avgs_work has been
highly optimized, however on systems with large number of cgroups the
overhead becomes noticeable.
Systems which use PSI only at the system level could avoid this overhead
if PSI can be configured to skip per-cgroup stall accounting.
Add "cgroup_disable=pressure" kernel command-line option to allow
requesting system-wide only pressure stall accounting. When set, it
keeps system-wide accounting under /proc/pressure/ but skips accounting
for individual cgroups and does not expose PSI nodes in cgroup hierarchy.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-06-08 14:59:02 -04:00
David S. Miller
126285651b Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net
Bug fixes overlapping feature additions and refactoring, mostly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 13:01:52 -07:00
Jan Kara
64c2c2c62f quota: Change quotactl_path() systcall to an fd-based one
Some users have pointed out that path-based syscalls are problematic in
some environments and at least directory fd argument and possibly also
resolve flags are desirable for such syscalls. Rather than
reimplementing all details of pathname lookup and following where it may
eventually evolve, let's go for full file descriptor based syscall
similar to how ioctl(2) works since the beginning. Managing of quotas
isn't performance sensitive so the extra overhead of open does not
matter and we are able to consume O_PATH descriptors as well which makes
open cheap anyway. Also for frequent operations (such as retrieving
usage information for all users) we can reuse single fd and in fact get
even better performance as well as avoiding races with possible remounts
etc.

Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2021-06-07 12:11:24 +02:00
Linus Torvalds
9d32fa5d74 Networking fixes for 5.13-rc5, including fixes from bpf, wireless,
netfilter and wireguard trees.
 
 The bpf vs lockdown+audit fix is the most notable.
 
 Current release - regressions:
 
  - virtio-net: fix page faults and crashes when XDP is enabled
 
  - mlx5e: fix HW timestamping with CQE compression, and make sure they
           are only allowed to coexist with capable devices
 
  - stmmac:
         - fix kernel panic due to NULL pointer dereference of mdio_bus_data
         - fix double clk unprepare when no PHY device is connected
 
 Current release - new code bugs:
 
  - mt76: a few fixes for the recent MT7921 devices and runtime
          power management
 
 Previous releases - regressions:
 
  - ice: - track AF_XDP ZC enabled queues in bitmap to fix copy mode Tx
         - fix allowing VF to request more/less queues via virtchnl
 	- correct supported and advertised autoneg by using PHY capabilities
         - allow all LLDP packets from PF to Tx
 
  - kbuild: quote OBJCOPY var to avoid a pahole call break the build
 
 Previous releases - always broken:
 
  - bpf, lockdown, audit: fix buggy SELinux lockdown permission checks
 
  - mt76: address the recent FragAttack vulnerabilities not covered
          by generic fixes
 
  - ipv6: fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
 
  - Bluetooth:
  	 - fix the erroneous flush_work() order, to avoid double free
          - use correct lock to prevent UAF of hdev object
 
  - nfc: fix NULL ptr dereference in llcp_sock_getname() after failed connect
 
  - ieee802154: multiple fixes to error checking and return values
 
  - igb: fix XDP with PTP enabled
 
  - intel: add correct exception tracing for XDP
 
  - tls: fix use-after-free when TLS offload device goes down and back up
 
  - ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service
 
  - netfilter: nft_ct: skip expectations for confirmed conntrack
 
  - mptcp: fix falling back to TCP in presence of out of order packets
           early in connection lifetime
 
  - wireguard: switch from O(n) to a O(1) algorithm for maintaining peers,
           fixing stalls and a large memory leak in the process
 
 Misc:
 
  - devlink: correct VIRTUAL port to not have phys_port attributes
 
  - Bluetooth: fix VIRTIO_ID_BT assigned number
 
  - net: return the correct errno code ENOBUF -> ENOMEM
 
  - wireguard:
          - peer: allocate in kmem_cache saving 25% on peer memory
          - do not use -O3
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Networking fixes, including fixes from bpf, wireless, netfilter and
  wireguard trees.

  The bpf vs lockdown+audit fix is the most notable.

  Things haven't slowed down just yet, both in terms of regressions in
  current release and largish fixes for older code, but we usually see a
  slowdown only after -rc5.

  Current release - regressions:

   - virtio-net: fix page faults and crashes when XDP is enabled

   - mlx5e: fix HW timestamping with CQE compression, and make sure they
     are only allowed to coexist with capable devices

   - stmmac:
      - fix kernel panic due to NULL pointer dereference of
        mdio_bus_data
      - fix double clk unprepare when no PHY device is connected

  Current release - new code bugs:

   - mt76: a few fixes for the recent MT7921 devices and runtime power
     management

  Previous releases - regressions:

   - ice:
      - track AF_XDP ZC enabled queues in bitmap to fix copy mode Tx
      - fix allowing VF to request more/less queues via virtchnl
      - correct supported and advertised autoneg by using PHY
        capabilities
      - allow all LLDP packets from PF to Tx

   - kbuild: quote OBJCOPY var to avoid a pahole call break the build

  Previous releases - always broken:

   - bpf, lockdown, audit: fix buggy SELinux lockdown permission checks

   - mt76: address the recent FragAttack vulnerabilities not covered by
     generic fixes

   - ipv6: fix KASAN: slab-out-of-bounds Read in
     fib6_nh_flush_exceptions

   - Bluetooth:
      - fix the erroneous flush_work() order, to avoid double free
      - use correct lock to prevent UAF of hdev object

   - nfc: fix NULL ptr dereference in llcp_sock_getname() after failed
     connect

   - ieee802154: multiple fixes to error checking and return values

   - igb: fix XDP with PTP enabled

   - intel: add correct exception tracing for XDP

   - tls: fix use-after-free when TLS offload device goes down and back
     up

   - ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service

   - netfilter: nft_ct: skip expectations for confirmed conntrack

   - mptcp: fix falling back to TCP in presence of out of order packets
     early in connection lifetime

   - wireguard: switch from O(n) to a O(1) algorithm for maintaining
     peers, fixing stalls and a large memory leak in the process

  Misc:

   - devlink: correct VIRTUAL port to not have phys_port attributes

   - Bluetooth: fix VIRTIO_ID_BT assigned number

   - net: return the correct errno code ENOBUF -> ENOMEM

   - wireguard:
      - peer: allocate in kmem_cache saving 25% on peer memory
      - do not use -O3"

* tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
  cxgb4: avoid link re-train during TC-MQPRIO configuration
  sch_htb: fix refcount leak in htb_parent_to_leaf_offload
  wireguard: allowedips: free empty intermediate nodes when removing single node
  wireguard: allowedips: allocate nodes in kmem_cache
  wireguard: allowedips: remove nodes in O(1)
  wireguard: allowedips: initialize list head in selftest
  wireguard: peer: allocate in kmem_cache
  wireguard: use synchronize_net rather than synchronize_rcu
  wireguard: do not use -O3
  wireguard: selftests: make sure rp_filter is disabled on vethc
  wireguard: selftests: remove old conntrack kconfig value
  virtchnl: Add missing padding to virtchnl_proto_hdrs
  ice: Allow all LLDP packets from PF to Tx
  ice: report supported and advertised autoneg using PHY capabilities
  ice: handle the VF VSI rebuild failure
  ice: Fix VFR issues for AVF drivers that expect ATQLEN cleared
  ice: Fix allowing VF to request more/less queues via virtchnl
  virtio-net: fix for skb_over_panic inside big mode
  ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
  fib: Return the correct errno code
  ...
2021-06-04 18:25:39 -07:00
Yang Li
2ca11b0e04 cgroup: Fix kernel-doc
Fix function name in cgroup.c and rstat.c kernel-doc comment
to remove these warnings found by clang_w1.

kernel/cgroup/cgroup.c:2401: warning: expecting prototype for
cgroup_taskset_migrate(). Prototype was for cgroup_migrate_execute()
instead.
kernel/cgroup/rstat.c:233: warning: expecting prototype for
cgroup_rstat_flush_begin(). Prototype was for cgroup_rstat_flush_hold()
instead.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: 'commit e595cd706982 ("cgroup: track migration context in cgroup_mgctx")'
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-06-04 10:51:07 -04:00
Eric Dumazet
1faa491a49 sched/debug: Remove obsolete init_schedstats()
Revert commit 4698f88c06b8 ("sched/debug: Fix 'schedstats=enable'
cmdline option").

After commit 6041186a3258 ("init: initialize jump labels before
command line option parsing") we can rely on jump label infra being
ready for use when setup_schedstats() is called.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20210602112108.1709635-1-eric.dumazet@gmail.com
2021-06-04 15:38:42 +02:00
Ingo Molnar
a9e906b71f Merge branch 'sched/urgent' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-06-03 19:00:49 +02:00
Dietmar Eggemann
68d7a19068 sched/fair: Fix util_est UTIL_AVG_UNCHANGED handling
The util_est internal UTIL_AVG_UNCHANGED flag which is used to prevent
unnecessary util_est updates uses the LSB of util_est.enqueued. It is
exposed via _task_util_est() (and task_util_est()).

Commit 92a801e5d5b7 ("sched/fair: Mask UTIL_AVG_UNCHANGED usages")
mentions that the LSB is lost for util_est resolution but
find_energy_efficient_cpu() checks if task_util_est() returns 0 to
return prev_cpu early.

_task_util_est() returns the max value of util_est.ewma and
util_est.enqueued or'ed w/ UTIL_AVG_UNCHANGED.
So task_util_est() returning the max of task_util() and
_task_util_est() will never return 0 under the default
SCHED_FEAT(UTIL_EST, true).

To fix this use the MSB of util_est.enqueued instead and keep the flag
util_est internal, i.e. don't export it via _task_util_est().

The maximal possible util_avg value for a task is 1024 so the MSB of
'unsigned int util_est.enqueued' isn't used to store a util value.

As a caveat the code behind the util_est_se trace point has to filter
UTIL_AVG_UNCHANGED to see the real util_est.enqueued value which should
be easy to do.

This also fixes an issue report by Xuewen Yan that util_est_update()
only used UTIL_AVG_UNCHANGED for the subtrahend of the equation:

  last_enqueued_diff = ue.enqueued - (task_util() | UTIL_AVG_UNCHANGED)

Fixes: b89997aa88f0b sched/pelt: Fix task util_est update filtering
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Xuewen Yan <xuewen.yan@unisoc.com>
Reviewed-by: Vincent Donnefort <vincent.donnefort@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20210602145808.1562603-1-dietmar.eggemann@arm.com
2021-06-03 15:47:23 +02:00
Vincent Guittot
fcf6631f37 sched/pelt: Ensure that *_sum is always synced with *_avg
Rounding in PELT calculation happening when entities are attached/detached
of a cfs_rq can result into situations where util/runnable_avg is not null
but util/runnable_sum is. This is normally not possible so we need to
ensure that util/runnable_sum stays synced with util/runnable_avg.

detach_entity_load_avg() is the last place where we don't sync
util/runnable_sum with util/runnbale_avg when moving some sched_entities

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210601085832.12626-1-vincent.guittot@linaro.org
2021-06-03 12:55:55 +02:00
Daniel Borkmann
ff40e51043 bpf, lockdown, audit: Fix buggy SELinux lockdown permission checks
Commit 59438b46471a ("security,lockdown,selinux: implement SELinux lockdown")
added an implementation of the locked_down LSM hook to SELinux, with the aim
to restrict which domains are allowed to perform operations that would breach
lockdown. This is indirectly also getting audit subsystem involved to report
events. The latter is problematic, as reported by Ondrej and Serhei, since it
can bring down the whole system via audit:

  1) The audit events that are triggered due to calls to security_locked_down()
     can OOM kill a machine, see below details [0].

  2) It also seems to be causing a deadlock via avc_has_perm()/slow_avc_audit()
     when trying to wake up kauditd, for example, when using trace_sched_switch()
     tracepoint, see details in [1]. Triggering this was not via some hypothetical
     corner case, but with existing tools like runqlat & runqslower from bcc, for
     example, which make use of this tracepoint. Rough call sequence goes like:

     rq_lock(rq) -> -------------------------+
       trace_sched_switch() ->               |
         bpf_prog_xyz() ->                   +-> deadlock
           selinux_lockdown() ->             |
             audit_log_end() ->              |
               wake_up_interruptible() ->    |
                 try_to_wake_up() ->         |
                   rq_lock(rq) --------------+

What's worse is that the intention of 59438b46471a to further restrict lockdown
settings for specific applications in respect to the global lockdown policy is
completely broken for BPF. The SELinux policy rule for the current lockdown check
looks something like this:

  allow <who> <who> : lockdown { <reason> };

However, this doesn't match with the 'current' task where the security_locked_down()
is executed, example: httpd does a syscall. There is a tracing program attached
to the syscall which triggers a BPF program to run, which ends up doing a
bpf_probe_read_kernel{,_str}() helper call. The selinux_lockdown() hook does
the permission check against 'current', that is, httpd in this example. httpd
has literally zero relation to this tracing program, and it would be nonsensical
having to write an SELinux policy rule against httpd to let the tracing helper
pass. The policy in this case needs to be against the entity that is installing
the BPF program. For example, if bpftrace would generate a histogram of syscall
counts by user space application:

  bpftrace -e 'tracepoint:raw_syscalls:sys_enter { @[comm] = count(); }'

bpftrace would then go and generate a BPF program from this internally. One way
of doing it [for the sake of the example] could be to call bpf_get_current_task()
helper and then access current->comm via one of bpf_probe_read_kernel{,_str}()
helpers. So the program itself has nothing to do with httpd or any other random
app doing a syscall here. The BPF program _explicitly initiated_ the lockdown
check. The allow/deny policy belongs in the context of bpftrace: meaning, you
want to grant bpftrace access to use these helpers, but other tracers on the
system like my_random_tracer _not_.

Therefore fix all three issues at the same time by taking a completely different
approach for the security_locked_down() hook, that is, move the check into the
program verification phase where we actually retrieve the BPF func proto. This
also reliably gets the task (current) that is trying to install the BPF tracing
program, e.g. bpftrace/bcc/perf/systemtap/etc, and it also fixes the OOM since
we're moving this out of the BPF helper's fast-path which can be called several
millions of times per second.

The check is then also in line with other security_locked_down() hooks in the
system where the enforcement is performed at open/load time, for example,
open_kcore() for /proc/kcore access or module_sig_check() for module signatures
just to pick few random ones. What's out of scope in the fix as well as in
other security_locked_down() hook locations /outside/ of BPF subsystem is that
if the lockdown policy changes on the fly there is no retrospective action.
This requires a different discussion, potentially complex infrastructure, and
it's also not clear whether this can be solved generically. Either way, it is
out of scope for a suitable stable fix which this one is targeting. Note that
the breakage is specifically on 59438b46471a where it started to rely on 'current'
as UAPI behavior, and _not_ earlier infrastructure such as 9d1f8be5cf42 ("bpf:
Restrict bpf when kernel lockdown is in confidentiality mode").

[0] https://bugzilla.redhat.com/show_bug.cgi?id=1955585, Jakub Hrozek says:

  I starting seeing this with F-34. When I run a container that is traced with
  BPF to record the syscalls it is doing, auditd is flooded with messages like:

  type=AVC msg=audit(1619784520.593:282387): avc:  denied  { confidentiality }
    for pid=476 comm="auditd" lockdown_reason="use of bpf to read kernel RAM"
      scontext=system_u:system_r:auditd_t:s0 tcontext=system_u:system_r:auditd_t:s0
        tclass=lockdown permissive=0

  This seems to be leading to auditd running out of space in the backlog buffer
  and eventually OOMs the machine.

  [...]
  auditd running at 99% CPU presumably processing all the messages, eventually I get:
  Apr 30 12:20:42 fedora kernel: audit: backlog limit exceeded
  Apr 30 12:20:42 fedora kernel: audit: backlog limit exceeded
  Apr 30 12:20:42 fedora kernel: audit: audit_backlog=2152579 > audit_backlog_limit=64
  Apr 30 12:20:42 fedora kernel: audit: audit_backlog=2152626 > audit_backlog_limit=64
  Apr 30 12:20:42 fedora kernel: audit: audit_backlog=2152694 > audit_backlog_limit=64
  Apr 30 12:20:42 fedora kernel: audit: audit_lost=6878426 audit_rate_limit=0 audit_backlog_limit=64
  Apr 30 12:20:45 fedora kernel: oci-seccomp-bpf invoked oom-killer: gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=-1000
  Apr 30 12:20:45 fedora kernel: CPU: 0 PID: 13284 Comm: oci-seccomp-bpf Not tainted 5.11.12-300.fc34.x86_64 #1
  Apr 30 12:20:45 fedora kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
  [...]

[1] https://lore.kernel.org/linux-audit/CANYvDQN7H5tVp47fbYcRasv4XF07eUbsDwT_eDCHXJUj43J7jQ@mail.gmail.com/,
    Serhei Makarov says:

  Upstream kernel 5.11.0-rc7 and later was found to deadlock during a
  bpf_probe_read_compat() call within a sched_switch tracepoint. The problem
  is reproducible with the reg_alloc3 testcase from SystemTap's BPF backend
  testsuite on x86_64 as well as the runqlat, runqslower tools from bcc on
  ppc64le. Example stack trace:

  [...]
  [  730.868702] stack backtrace:
  [  730.869590] CPU: 1 PID: 701 Comm: in:imjournal Not tainted, 5.12.0-0.rc2.20210309git144c79ef3353.166.fc35.x86_64 #1
  [  730.871605] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
  [  730.873278] Call Trace:
  [  730.873770]  dump_stack+0x7f/0xa1
  [  730.874433]  check_noncircular+0xdf/0x100
  [  730.875232]  __lock_acquire+0x1202/0x1e10
  [  730.876031]  ? __lock_acquire+0xfc0/0x1e10
  [  730.876844]  lock_acquire+0xc2/0x3a0
  [  730.877551]  ? __wake_up_common_lock+0x52/0x90
  [  730.878434]  ? lock_acquire+0xc2/0x3a0
  [  730.879186]  ? lock_is_held_type+0xa7/0x120
  [  730.880044]  ? skb_queue_tail+0x1b/0x50
  [  730.880800]  _raw_spin_lock_irqsave+0x4d/0x90
  [  730.881656]  ? __wake_up_common_lock+0x52/0x90
  [  730.882532]  __wake_up_common_lock+0x52/0x90
  [  730.883375]  audit_log_end+0x5b/0x100
  [  730.884104]  slow_avc_audit+0x69/0x90
  [  730.884836]  avc_has_perm+0x8b/0xb0
  [  730.885532]  selinux_lockdown+0xa5/0xd0
  [  730.886297]  security_locked_down+0x20/0x40
  [  730.887133]  bpf_probe_read_compat+0x66/0xd0
  [  730.887983]  bpf_prog_250599c5469ac7b5+0x10f/0x820
  [  730.888917]  trace_call_bpf+0xe9/0x240
  [  730.889672]  perf_trace_run_bpf_submit+0x4d/0xc0
  [  730.890579]  perf_trace_sched_switch+0x142/0x180
  [  730.891485]  ? __schedule+0x6d8/0xb20
  [  730.892209]  __schedule+0x6d8/0xb20
  [  730.892899]  schedule+0x5b/0xc0
  [  730.893522]  exit_to_user_mode_prepare+0x11d/0x240
  [  730.894457]  syscall_exit_to_user_mode+0x27/0x70
  [  730.895361]  entry_SYSCALL_64_after_hwframe+0x44/0xae
  [...]

Fixes: 59438b46471a ("security,lockdown,selinux: implement SELinux lockdown")
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Reported-by: Jakub Hrozek <jhrozek@redhat.com>
Reported-by: Serhei Makarov <smakarov@redhat.com>
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris <jamorris@linux.microsoft.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Frank Eigler <fche@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/bpf/01135120-8bf7-df2e-cff0-1d73f1f841c3@iogearbox.net
2021-06-02 21:59:22 +02:00
Valentin Schneider
475ea6c602 sched: Don't defer CPU pick to migration_cpu_stop()
Will reported that the 'XXX __migrate_task() can fail' in migration_cpu_stop()
can happen, and it *is* sort of a big deal. Looking at it some more, one
will note there is a glaring hole in the deferred CPU selection:

  (w/ CONFIG_CPUSET=n, so that the affinity mask passed via taskset doesn't
  get AND'd with cpu_online_mask)

  $ taskset -pc 0-2 $PID
  # offline CPUs 3-4
  $ taskset -pc 3-5 $PID
    `\
      $PID may stay on 0-2 due to the cpumask_any_distribute() picking an
      offline CPU and __migrate_task() refusing to do anything due to
      cpu_is_allowed().

set_cpus_allowed_ptr() goes to some length to pick a dest_cpu that matches
the right constraints vs affinity and the online/active state of the
CPUs. Reuse that instead of discarding it in the affine_move_task() case.

Fixes: 6d337eab041d ("sched: Fix migrate_disable() vs set_cpus_allowed_ptr()")
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210526205751.842360-2-valentin.schneider@arm.com
2021-06-01 16:00:11 +02:00
Odin Ugedal
08f7c2f4d0 sched/fair: Fix ascii art by relpacing tabs
When using something other than 8 spaces per tab, this ascii art
makes not sense, and the reader might end up wondering what this
advanced equation "is".

Signed-off-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210518125202.78658-4-odin@uged.al
2021-06-01 16:00:11 +02:00
Peter Zijlstra
15faafc6b4 sched,init: Fix DEBUG_PREEMPT vs early boot
Extend 8fb12156b8db ("init: Pin init task to the boot CPU, initially")
to cover the new PF_NO_SETAFFINITY requirement.

While there, move wait_for_completion(&kthreadd_done) into kernel_init()
to make it absolutely clear it is the very first thing done by the init
thread.

Fixes: 570a752b7a9b ("lib/smp_processor_id: Use is_percpu_thread() instead of nr_cpus_allowed")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/YLS4mbKUrA3Gnb4t@hirez.programming.kicks-ass.net
2021-06-01 16:00:11 +02:00
Peter Zijlstra
7b419f47fa sched: Add CONFIG_SCHED_CORE help text
Hugh noted that the SCHED_CORE Kconfig option could do with a help
text.

Requested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Hugh Dickins <hughd@google.com>
Link: https://lkml.kernel.org/r/YKyhtwhEgvtUDOyl@hirez.programming.kicks-ass.net
2021-06-01 16:00:10 +02:00
Peter Zijlstra
ec6aba3d2b kprobes: Remove kprobe::fault_handler
The reason for kprobe::fault_handler(), as given by their comment:

 * We come here because instructions in the pre/post
 * handler caused the page_fault, this could happen
 * if handler tries to access user space by
 * copy_from_user(), get_user() etc. Let the
 * user-specified handler try to fix it first.

Is just plain bad. Those other handlers are ran from non-preemptible
context and had better use _nofault() functions. Also, there is no
upstream usage of this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20210525073213.561116662@infradead.org
2021-06-01 16:00:08 +02:00
Qiujun Huang
9ce4d216fe uprobes: Update uprobe_write_opcode() kernel-doc comment
commit 6d43743e9079 ("Uprobe: Additional argument arch_uprobe to
uprobe_write_opcode()") added the parameter @auprobe.

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210524041411.157027-1-hqjagain@gmail.com
2021-06-01 16:00:08 +02:00
Harishankar Vishwanathan
05924717ac bpf, tnums: Provably sound, faster, and more precise algorithm for tnum_mul
This patch introduces a new algorithm for multiplication of tristate
numbers (tnums) that is provably sound. It is faster and more precise when
compared to the existing method.

Like the existing method, this new algorithm follows the long
multiplication algorithm. The idea is to generate partial products by
multiplying each bit in the multiplier (tnum a) with the multiplicand
(tnum b), and adding the partial products after appropriately bit-shifting
them. The new algorithm, however, uses just a single loop over the bits of
the multiplier (tnum a) and accumulates only the uncertain components of
the multiplicand (tnum b) into a mask-only tnum. The following paper
explains the algorithm in more detail: https://arxiv.org/abs/2105.05398.

A natural way to construct the tnum product is by performing a tnum
addition on all the partial products. This algorithm presents another
method of doing this: decompose each partial product into two tnums,
consisting of the values and the masks separately. The mask-sum is
accumulated within the loop in acc_m. The value-sum tnum is generated
using a.value * b.value. The tnum constructed by tnum addition of the
value-sum and the mask-sum contains all possible summations of concrete
values drawn from the partial product tnums pairwise. We prove this result
in the paper.

Our evaluations show that the new algorithm is overall more precise
(producing tnums with less uncertain components) than the existing method.
As an illustrative example, consider the input tnums A and B. The numbers
in the parenthesis correspond to (value;mask).

  A                = 000000x1 (1;2)
  B                = 0010011x (38;1)
  A * B (existing) = xxxxxxxx (0;255)
  A * B (new)      = 0x1xxxxx (32;95)

Importantly, we present a proof of soundness of the new algorithm in the
aforementioned paper. Additionally, we show that this new algorithm is
empirically faster than the existing method.

Co-developed-by: Matan Shachnai <m.shachnai@rutgers.edu>
Co-developed-by: Srinivas Narayana <srinivas.narayana@rutgers.edu>
Co-developed-by: Santosh Nagarakatte <santosh.nagarakatte@rutgers.edu>
Signed-off-by: Matan Shachnai <m.shachnai@rutgers.edu>
Signed-off-by: Srinivas Narayana <srinivas.narayana@rutgers.edu>
Signed-off-by: Santosh Nagarakatte <santosh.nagarakatte@rutgers.edu>
Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan@rutgers.edu>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://arxiv.org/abs/2105.05398
Link: https://lore.kernel.org/bpf/20210531020157.7386-1-harishankar.vishwanathan@rutgers.edu
2021-06-01 13:34:15 +02:00
Will Deacon
245a057fee timer_list: Print name of per-cpu wakeup device
With the introduction of per-cpu wakeup devices that can be used in
preference to the broadcast timer, print the name of such devices when
they are available.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-6-will@kernel.org
2021-05-31 17:04:49 +02:00
Will Deacon
ea5c7f1b9a tick/broadcast: Program wakeup timer when entering idle if required
When configuring the broadcast timer on entry to and exit from deep idle
states, prefer a per-CPU wakeup timer if one exists.

On entry to idle, stop the tick device and transfer the next event into
the oneshot wakeup device, which will serve as the wakeup from idle. To
avoid the overhead of additional hardware accesses on exit from idle,
leave the timer armed and treat the inevitable interrupt as a (possibly
spurious) tick event.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-5-will@kernel.org
2021-05-31 17:04:46 +02:00
Will Deacon
c94a8537df tick/broadcast: Prefer per-cpu oneshot wakeup timers to broadcast
Some SoCs have two per-cpu timer implementations where the timer with the
higher rating stops in deep idle (i.e. suffers from CLOCK_EVT_FEAT_C3STOP)
but is otherwise preferable to the timer with the lower rating. In such a
design, selecting the higher rated devices relies on a global broadcast
timer and IPIs to wake up from deep idle states.

To avoid the reliance on a global broadcast timer and also to reduce the
overhead associated with the IPI wakeups, extend
tick_install_broadcast_device() to manage per-cpu wakeup timers separately
from the broadcast device.

For now, these timers remain unused.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-4-will@kernel.org
2021-05-31 17:04:45 +02:00
Will Deacon
e5007c288e tick/broadcast: Split __tick_broadcast_oneshot_control() into a helper
In preparation for adding support for per-cpu wakeup timers, split
_tick_broadcast_oneshot_control() into a helper function which deals
only with the broadcast timer management across idle transitions.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-3-will@kernel.org
2021-05-31 17:04:45 +02:00
Will Deacon
c2d4fee3f6 tick/broadcast: Drop unneeded CONFIG_GENERIC_CLOCKEVENTS_BROADCAST guard
tick-broadcast.o is only built if CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y
so remove the redundant #ifdef guards around the definition of
tick_receive_broadcast().

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210524221818.15850-2-will@kernel.org
2021-05-31 17:04:44 +02:00
YueHaibing
1fa98d96ea clockevents: Use DEVICE_ATTR_[RO|WO] macros
Use the DEVICE_ATTR_[RO|WO] helpers instead of plain DEVICE_ATTR, which
makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210523065825.19684-1-yuehaibing@huawei.com
2021-05-31 17:04:42 +02:00
Marco Elver
6c605f8371 perf: Fix data race between pin_count increment/decrement
KCSAN reports a data race between increment and decrement of pin_count:

  write to 0xffff888237c2d4e0 of 4 bytes by task 15740 on cpu 1:
   find_get_context		kernel/events/core.c:4617
   __do_sys_perf_event_open	kernel/events/core.c:12097 [inline]
   __se_sys_perf_event_open	kernel/events/core.c:11933
   ...
  read to 0xffff888237c2d4e0 of 4 bytes by task 15743 on cpu 0:
   perf_unpin_context		kernel/events/core.c:1525 [inline]
   __do_sys_perf_event_open	kernel/events/core.c:12328 [inline]
   __se_sys_perf_event_open	kernel/events/core.c:11933
   ...

Because neither read-modify-write here is atomic, this can lead to one
of the operations being lost, resulting in an inconsistent pin_count.
Fix it by adding the missing locking in the CPU-event case.

Fixes: fe4b04fa31a6 ("perf: Cure task_oncpu_function_call() races")
Reported-by: syzbot+142c9018f5962db69c7e@syzkaller.appspotmail.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210527104711.2671610-1-elver@google.com
2021-05-31 10:14:51 +02:00
Frederic Weisbecker
f268c3737e tick/nohz: Only check for RCU deferred wakeup on user/guest entry when needed
Checking for and processing RCU-nocb deferred wakeup upon user/guest
entry is only relevant when nohz_full runs on the local CPU, otherwise
the periodic tick should take care of it.

Make sure we don't needlessly pollute these fast-paths as a -3%
performance regression on a will-it-scale.per_process_ops has been
reported so far.

Fixes: 47b8ff194c1f (entry: Explicitly flush pending rcuog wakeup before last rescheduling point)
Fixes: 4ae7dc97f726 (entry/kvm: Explicitly flush pending rcuog wakeup before last rescheduling point)
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20210527113441.465489-1-frederic@kernel.org
2021-05-31 10:14:49 +02:00
Vincent Guittot
02da26ad5e sched/fair: Make sure to update tg contrib for blocked load
During the update of fair blocked load (__update_blocked_fair()), we
update the contribution of the cfs in tg->load_avg if cfs_rq's pelt
has decayed.  Nevertheless, the pelt values of a cfs_rq could have
been recently updated while propagating the change of a child. In this
case, cfs_rq's pelt will not decayed because it has already been
updated and we don't update tg->load_avg.

__update_blocked_fair
  ...
  for_each_leaf_cfs_rq_safe: child cfs_rq
    update cfs_rq_load_avg() for child cfs_rq
    ...
    update_load_avg(cfs_rq_of(se), se, 0)
      ...
      update cfs_rq_load_avg() for parent cfs_rq
		-propagation of child's load makes parent cfs_rq->load_sum
		 becoming null
        -UPDATE_TG is not set so it doesn't update parent
		 cfs_rq->tg_load_avg_contrib
  ..
  for_each_leaf_cfs_rq_safe: parent cfs_rq
    update cfs_rq_load_avg() for parent cfs_rq
      - nothing to do because parent cfs_rq has already been updated
		recently so cfs_rq->tg_load_avg_contrib is not updated
    ...
    parent cfs_rq is decayed
      list_del_leaf_cfs_rq parent cfs_rq
	  - but it still contibutes to tg->load_avg

we must set UPDATE_TG flags when propagting pending load to the parent

Fixes: 039ae8bcf7a5 ("sched/fair: Fix O(nr_cgroups) in the load balancing path")
Reported-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Odin Ugedal <odin@uged.al>
Link: https://lkml.kernel.org/r/20210527122916.27683-3-vincent.guittot@linaro.org
2021-05-31 10:14:48 +02:00
Vincent Guittot
7c7ad626d9 sched/fair: Keep load_avg and load_sum synced
when removing a cfs_rq from the list we only check _sum value so we must
ensure that _avg and _sum stay synced so load_sum can't be null whereas
load_avg is not after propagating load in the cgroup hierarchy.

Use load_avg to compute load_sum similarly to what is done for util_sum
and runnable_sum.

Fixes: 0e2d2aaaae52 ("sched/fair: Rewrite PELT migration propagation")
Reported-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Odin Ugedal <odin@uged.al>
Link: https://lkml.kernel.org/r/20210527122916.27683-2-vincent.guittot@linaro.org
2021-05-31 10:14:48 +02:00
Linus Torvalds
9a76c0ee3a seccomp fixes for v5.13-rc4
- Fix addfd notification race condition (Sargun Dhillon)
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Merge tag 'seccomp-fixes-v5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull seccomp fixes from Kees Cook:
 "This fixes a hard-to-hit race condition in the addfd user_notif
  feature of seccomp, visible since v5.9.

  And a small documentation fix"

* tag 'seccomp-fixes-v5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  seccomp: Refactor notification handler to prepare for new semantics
  Documentation: seccomp: Fix user notification documentation
2021-05-29 18:16:09 -10:00
Sargun Dhillon
ddc4739169 seccomp: Refactor notification handler to prepare for new semantics
This refactors the user notification code to have a do / while loop around
the completion condition. This has a small change in semantic, in that
previously we ignored addfd calls upon wakeup if the notification had been
responded to, but instead with the new change we check for an outstanding
addfd calls prior to returning to userspace.

Rodrigo Campos also identified a bug that can result in addfd causing
an early return, when the supervisor didn't actually handle the
syscall [1].

[1]: https://lore.kernel.org/lkml/20210413160151.3301-1-rodrigo@kinvolk.io/

Fixes: 7cf97b125455 ("seccomp: Introduce addfd ioctl to seccomp user notifier")
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Tycho Andersen <tycho@tycho.pizza>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Rodrigo Campos <rodrigo@kinvolk.io>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210517193908.3113-3-sargun@sargun.me
2021-05-29 11:13:27 -07:00
Hangbin Liu
e8e0f0f484 bpf, devmap: Remove drops variable from bq_xmit_all()
As Colin pointed out, the first drops assignment after declaration will
be overwritten by the second drops assignment before using, which makes
it useless.

Since the drops variable will be used only once. Just remove it and
use "cnt - sent" in trace_xdp_devmap_xmit().

Fixes: cb261b594b41 ("bpf: Run devmap xdp_prog on flush instead of bulk enqueue")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210528024356.24333-1-liuhangbin@gmail.com
2021-05-28 22:14:18 +02:00
Yang Yingliang
5e6b8a50a7 cred: add missing return error code when set_cred_ucounts() failed
If set_cred_ucounts() failed, we need return the error code.

Fixes: 905ae01c4ae2 ("Add a reference to ucounts for each cred")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lkml.kernel.org/r/20210526143805.2549649-1-yangyingliang@huawei.com
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-05-28 13:12:52 -05:00
Jakub Kicinski
5ada57a9a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
cdc-wdm: s/kill_urbs/poison_urbs/ to fix build

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-27 09:55:10 -07:00
Haocheng Xie
875dd7bf54 perf/hw_breakpoint: Fix DocBook warnings in perf hw_breakpoint
Fix the following W=1 kernel build warning(s):

  kernel/events/hw_breakpoint.c:461: warning: Function parameter or member 'context' not described in 'register_user_hw_breakpoint'
  kernel/events/hw_breakpoint.c:560: warning: Function parameter or member 'context' not described in 'register_wide_hw_breakpoint'

Signed-off-by: Haocheng Xie <xiehaocheng.cn@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210527031947.1801-4-xiehaocheng.cn@gmail.com
2021-05-27 09:35:22 +02:00
Haocheng Xie
a1ddf5249f perf/core: Fix DocBook warnings
Fix the following W=1 kernel build warning(s):

  kernel/events/core.c:143: warning: Function parameter or member 'cpu' not described in 'cpu_function_call'
  kernel/events/core.c:11924: warning: Function parameter or member 'flags' not described in 'sys_perf_event_open'
  kernel/events/core.c:12382: warning: Function parameter or member 'overflow_handler' not described in 'perf_event_create_kernel_counter'
  kernel/events/core.c:12382: warning: Function parameter or member 'context' not described in 'perf_event_create_kernel_counter'

Signed-off-by: Haocheng Xie <xiehaocheng.cn@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210527031947.1801-3-xiehaocheng.cn@gmail.com
2021-05-27 09:35:21 +02:00
Haocheng Xie
32961aecf9 perf/core: Make local function perf_pmu_snapshot_aux() static
Fixes the following W=1 kernel build warning:

  kernel/events/core.c:6670:6: warning: no previous prototype for 'perf_pmu_snapshot_aux' [-Wmissing-prototypes]

Signed-off-by: Haocheng Xie <xiehaocheng.cn@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210527031947.1801-2-xiehaocheng.cn@gmail.com
2021-05-27 09:35:21 +02:00
Linus Torvalds
d7c5303fbc Networking fixes for 5.13-rc4, including fixes from bpf, netfilter,
can and wireless trees. Notably including fixes for the recently
 announced "FragAttacks" WiFi vulnerabilities. Rather large batch,
 touching some core parts of the stack, too, but nothing hair-raising.
 
 Current release - regressions:
 
  - tipc: make node link identity publish thread safe
 
  - dsa: felix: re-enable TAS guard band mode
 
  - stmmac: correct clocks enabled in stmmac_vlan_rx_kill_vid()
 
  - stmmac: fix system hang if change mac address after interface ifdown
 
 Current release - new code bugs:
 
  - mptcp: avoid OOB access in setsockopt()
 
  - bpf: Fix nested bpf_bprintf_prepare with more per-cpu buffers
 
  - ethtool: stats: fix a copy-paste error - init correct array size
 
 Previous releases - regressions:
 
  - sched: fix packet stuck problem for lockless qdisc
 
  - net: really orphan skbs tied to closing sk
 
  - mlx4: fix EEPROM dump support
 
  - bpf: fix alu32 const subreg bound tracking on bitwise operations
 
  - bpf: fix mask direction swap upon off reg sign change
 
  - bpf, offload: reorder offload callback 'prepare' in verifier
 
  - stmmac: Fix MAC WoL not working if PHY does not support WoL
 
  - packetmmap: fix only tx timestamp on request
 
  - tipc: skb_linearize the head skb when reassembling msgs
 
 Previous releases - always broken:
 
  - mac80211: address recent "FragAttacks" vulnerabilities
 
  - mac80211: do not accept/forward invalid EAPOL frames
 
  - mptcp: avoid potential error message floods
 
  - bpf, ringbuf: deny reserve of buffers larger than ringbuf to prevent
                  out of buffer writes
 
  - bpf: forbid trampoline attach for functions with variable arguments
 
  - bpf: add deny list of functions to prevent inf recursion of tracing
         programs
 
  - tls splice: check SPLICE_F_NONBLOCK instead of MSG_DONTWAIT
 
  - can: isotp: prevent race between isotp_bind() and isotp_setsockopt()
 
  - netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check,
               fallback to non-AVX2 version
 
 Misc:
 
  - bpf: add kconfig knob for disabling unpriv bpf by default
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Merge tag 'net-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.13-rc4, including fixes from bpf, netfilter,
  can and wireless trees. Notably including fixes for the recently
  announced "FragAttacks" WiFi vulnerabilities. Rather large batch,
  touching some core parts of the stack, too, but nothing hair-raising.

  Current release - regressions:

   - tipc: make node link identity publish thread safe

   - dsa: felix: re-enable TAS guard band mode

   - stmmac: correct clocks enabled in stmmac_vlan_rx_kill_vid()

   - stmmac: fix system hang if change mac address after interface
     ifdown

  Current release - new code bugs:

   - mptcp: avoid OOB access in setsockopt()

   - bpf: Fix nested bpf_bprintf_prepare with more per-cpu buffers

   - ethtool: stats: fix a copy-paste error - init correct array size

  Previous releases - regressions:

   - sched: fix packet stuck problem for lockless qdisc

   - net: really orphan skbs tied to closing sk

   - mlx4: fix EEPROM dump support

   - bpf: fix alu32 const subreg bound tracking on bitwise operations

   - bpf: fix mask direction swap upon off reg sign change

   - bpf, offload: reorder offload callback 'prepare' in verifier

   - stmmac: Fix MAC WoL not working if PHY does not support WoL

   - packetmmap: fix only tx timestamp on request

   - tipc: skb_linearize the head skb when reassembling msgs

  Previous releases - always broken:

   - mac80211: address recent "FragAttacks" vulnerabilities

   - mac80211: do not accept/forward invalid EAPOL frames

   - mptcp: avoid potential error message floods

   - bpf, ringbuf: deny reserve of buffers larger than ringbuf to
     prevent out of buffer writes

   - bpf: forbid trampoline attach for functions with variable arguments

   - bpf: add deny list of functions to prevent inf recursion of tracing
     programs

   - tls splice: check SPLICE_F_NONBLOCK instead of MSG_DONTWAIT

   - can: isotp: prevent race between isotp_bind() and
     isotp_setsockopt()

   - netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check,
     fallback to non-AVX2 version

  Misc:

   - bpf: add kconfig knob for disabling unpriv bpf by default"

* tag 'net-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (172 commits)
  net: phy: Document phydev::dev_flags bits allocation
  mptcp: validate 'id' when stopping the ADD_ADDR retransmit timer
  mptcp: avoid error message on infinite mapping
  mptcp: drop unconditional pr_warn on bad opt
  mptcp: avoid OOB access in setsockopt()
  nfp: update maintainer and mailing list addresses
  net: mvpp2: add buffer header handling in RX
  bnx2x: Fix missing error code in bnx2x_iov_init_one()
  net: zero-initialize tc skb extension on allocation
  net: hns: Fix kernel-doc
  sctp: fix the proc_handler for sysctl encap_port
  sctp: add the missing setting for asoc encap_port
  bpf, selftests: Adjust few selftest result_unpriv outcomes
  bpf: No need to simulate speculative domain for immediates
  bpf: Fix mask direction swap upon off reg sign change
  bpf: Wrap aux data inside bpf_sanitize_info container
  bpf: Fix BPF_LSM kconfig symbol dependency
  selftests/bpf: Add test for l3 use of bpf_redirect_peer
  bpftool: Add sock_release help info for cgroup attach/prog load command
  net: dsa: microchip: enable phy errata workaround on 9567
  ...
2021-05-26 17:44:49 -10:00
Florent Revest
d6a6a55518 libbpf: Move BPF_SEQ_PRINTF and BPF_SNPRINTF to bpf_helpers.h
These macros are convenient wrappers around the bpf_seq_printf and
bpf_snprintf helpers. They are currently provided by bpf_tracing.h which
targets low level tracing primitives. bpf_helpers.h is a better fit.

The __bpf_narg and __bpf_apply are needed in both files and provided
twice. __bpf_empty isn't used anywhere and is removed from bpf_tracing.h

Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210526164643.2881368-1-revest@chromium.org
2021-05-26 10:45:41 -07:00