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Author SHA1 Message Date
Ye Bin
39fbef4b0f PM: hibernate: Get block device exclusively in swsusp_check()
The following kernel crash can be triggered:

[   89.266592] ------------[ cut here ]------------
[   89.267427] kernel BUG at fs/buffer.c:3020!
[   89.268264] invalid opcode: 0000 [#1] SMP KASAN PTI
[   89.269116] CPU: 7 PID: 1750 Comm: kmmpd-loop0 Not tainted 5.10.0-862.14.0.6.x86_64-08610-gc932cda3cef4-dirty #20
[   89.273169] RIP: 0010:submit_bh_wbc.isra.0+0x538/0x6d0
[   89.277157] RSP: 0018:ffff888105ddfd08 EFLAGS: 00010246
[   89.278093] RAX: 0000000000000005 RBX: ffff888124231498 RCX: ffffffffb2772612
[   89.279332] RDX: 1ffff11024846293 RSI: 0000000000000008 RDI: ffff888124231498
[   89.280591] RBP: ffff8881248cc000 R08: 0000000000000001 R09: ffffed1024846294
[   89.281851] R10: ffff88812423149f R11: ffffed1024846293 R12: 0000000000003800
[   89.283095] R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881161f7000
[   89.284342] FS:  0000000000000000(0000) GS:ffff88839b5c0000(0000) knlGS:0000000000000000
[   89.285711] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.286701] CR2: 00007f166ebc01a0 CR3: 0000000435c0e000 CR4: 00000000000006e0
[   89.287919] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   89.289138] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   89.290368] Call Trace:
[   89.290842]  write_mmp_block+0x2ca/0x510
[   89.292218]  kmmpd+0x433/0x9a0
[   89.294902]  kthread+0x2dd/0x3e0
[   89.296268]  ret_from_fork+0x22/0x30
[   89.296906] Modules linked in:

by running the following commands:

 1. mkfs.ext4 -O mmp  /dev/sda -b 1024
 2. mount /dev/sda /home/test
 3. echo "/dev/sda" > /sys/power/resume

That happens because swsusp_check() calls set_blocksize() on the
target partition which confuses the file system:

       Thread1                       Thread2
mount /dev/sda /home/test
get s_mmp_bh  --> has mapped flag
start kmmpd thread
				echo "/dev/sda" > /sys/power/resume
				  resume_store
				    software_resume
				      swsusp_check
				        set_blocksize
					  truncate_inode_pages_range
					    truncate_cleanup_page
					      block_invalidatepage
					        discard_buffer --> clean mapped flag
write_mmp_block
  submit_bh
    submit_bh_wbc
      BUG_ON(!buffer_mapped(bh))

To address this issue, modify swsusp_check() to open the target block
device with exclusive access.

Signed-off-by: Ye Bin <yebin10@huawei.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-21 19:38:32 +02:00
Cai Huoqing
9437e39377 PM: hibernate: swap: Use vzalloc() and kzalloc()
Replace vmalloc()/memset() with vzalloc() and kmalloc()/memset() with
kzalloc() to simplify the code.

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-21 13:04:57 +02:00
Anders Roxell
01de5fcd8b PM: hibernate: fix sparse warnings
When building the kernel with sparse enabled 'C=1' the following
warnings shows up:

kernel/power/swap.c:390:29: warning: incorrect type in assignment (different base types)
kernel/power/swap.c:390:29:    expected int ret
kernel/power/swap.c:390:29:    got restricted blk_status_t

This is due to function hib_wait_io() returns a 'blk_status_t' which is
a bitwise u8. Commit 5416da01ff ("PM: hibernate: Remove
blk_status_to_errno in hib_wait_io") seemed to have mixed up the return
type. However, the 4e4cbee93d ("block: switch bios to blk_status_t")
actually broke the behaviour by returning the wrong type.

Rework so function hib_wait_io() returns a 'int' instead of
'blk_status_t' and make sure to call function
blk_status_to_errno(hb->error)' when returning from function
hib_wait_io() a int gets returned.

Fixes: 4e4cbee93d ("block: switch bios to blk_status_t")
Fixes: 5416da01ff ("PM: hibernate: Remove blk_status_to_errno in hib_wait_io")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-21 12:45:18 +02:00
Jiri Olsa
130c080658 tracing: Add trampoline/graph selftest
Adding selftest for checking that direct trampoline can
co-exist together with graph tracer on same function.

This is supported for CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
config option, which is defined only for x86_64 for now.

Link: https://lkml.kernel.org/r/20211008091336.33616-5-jolsa@kernel.org

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-20 23:44:44 -04:00
Steven Rostedt (VMware)
0c0593b45c x86/ftrace: Make function graph use ftrace directly
We don't need special hook for graph tracer entry point,
but instead we can use graph_ops::func function to install
the return_hooker.

This moves the graph tracing setup _before_ the direct
trampoline prepares the stack, so the return_hooker will
be called when the direct trampoline is finished.

This simplifies the code, because we don't need to take into
account the direct trampoline setup when preparing the graph
tracer hooker and we can allow function graph tracer on entries
registered with direct trampoline.

Link: https://lkml.kernel.org/r/20211008091336.33616-4-jolsa@kernel.org

[fixed compile error reported by kernel test robot <lkp@intel.com>]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-20 23:44:43 -04:00
Linus Torvalds
515dcc2e02 dma-mapping fixes for Linux 5.15
- fix more dma-debug fallout (Gerald Schaefer, Hamza Mahfooz)
  - fix a kerneldoc warning (Logan Gunthorpe)
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Merge tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:

 - fix more dma-debug fallout (Gerald Schaefer, Hamza Mahfooz)

 - fix a kerneldoc warning (Logan Gunthorpe)

* tag 'dma-mapping-5.15-2' of git://git.infradead.org/users/hch/dma-mapping:
  dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC
  dma-debug: fix sg checks in debug_dma_map_sg()
  dma-mapping: fix the kerneldoc for dma_map_sgtable()
2021-10-20 10:16:51 -10:00
Florian Fainelli
945486bf1e genirq: Export irq_gc_noop()
In order to build drivers/irqchip/irq-bcm7120-l2.c as a module which
references irq_gc_noop(), we need to export it towards modules.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211020184859.2705451-10-f.fainelli@gmail.com
2021-10-20 20:06:33 +01:00
Florian Fainelli
fcd0f63dec genirq: Export irq_gc_{unmask_enable,mask_disable}_reg
In order to allow drivers/irqchip/irq-brcmstb-l2.c to be built as a
module we need to export: irq_gc_unmask_enable_reg() and
irq_gc_mask_disable_reg().

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211020184859.2705451-8-f.fainelli@gmail.com
2021-10-20 20:06:33 +01:00
Eric W. Biederman
a52f60fa29 reboot: Remove the unreachable panic after do_exit in reboot(2)
Link: https://lkml.kernel.org/r/20211020174406.17889-3-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-10-20 13:09:51 -05:00
Quentin Monnet
5f52d47c5f bpf/preload: Clean up .gitignore and "clean-files" target
kernel/bpf/preload/Makefile was recently updated to have it install
libbpf's headers locally instead of pulling them from tools/lib/bpf. But
two items still need to be addressed.

First, the local .gitignore file was not adjusted to ignore the files
generated in the new kernel/bpf/preload/libbpf output directory.

Second, the "clean-files" target is now incorrect. The old artefacts
names were not removed from the target, while the new ones were added
incorrectly. This is because "clean-files" expects names relative to
$(obj), but we passed the absolute path instead. This results in the
output and header-destination directories for libbpf (and their
contents) not being removed from kernel/bpf/preload on "make clean" from
the root of the repository.

This commit fixes both issues. Note that $(userprogs) needs not be added
to "clean-files", because the cleaning infrastructure already accounts
for it.

Cleaning the files properly also prevents make from printing the
following message, for builds coming after a "make clean":
"make[4]: Nothing to be done for 'install_headers'."

v2: Simplify the "clean-files" target.

Fixes: bf60791741 ("bpf: preload: Install libbpf headers when building")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211020094647.15564-1-quentin@isovalent.com
2021-10-20 10:39:04 -07:00
Imran Khan
55df0933be workqueue: Introduce show_one_worker_pool and show_one_workqueue.
Currently show_workqueue_state shows the state of all workqueues and of
all worker pools. In certain cases we may need to dump state of only a
specific workqueue or worker pool. For example in destroy_workqueue we
only need to show state of the workqueue which is getting destroyed.

So rename show_workqueue_state to show_all_workqueues(to signify it
dumps state of all busy workqueues) and divide it into more granular
functions (show_one_workqueue and show_one_worker_pool), that would show
states of individual workqueues and worker pools and can be used in
cases such as the one mentioned above.

Also, as mentioned earlier, make destroy_workqueue dump data pertaining
to only the workqueue that is being destroyed and make user(s) of
earlier interface(show_workqueue_state), use new interface
(show_all_workqueues).

Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-10-20 06:19:03 -10:00
Linus Torvalds
6da52dead8 audit/stable-5.15 PR 20211019
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Merge tag 'audit-pr-20211019' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit fix from Paul Moore:
 "One small audit patch to add a pointer NULL check"

* tag 'audit-pr-20211019' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: fix possible null-pointer dereference in audit_filter_rules
2021-10-20 06:11:17 -10:00
Linus Torvalds
fc9b289344 tracing recursion fix:
- While cleaning up some of the tracing recursion protection logic,
    I discovered a scenario that the current design would miss, and
    would allow an infinite recursion. Removing an optimization trick
    that opened the hole, fixes the issue and cleans up the code as well.
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Merge tag 'trace-v5.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Recursion fix for tracing.

  While cleaning up some of the tracing recursion protection logic, I
  discovered a scenario that the current design would miss, and would
  allow an infinite recursion. Removing an optimization trick that
  opened the hole fixes the issue and cleans up the code as well"

* tag 'trace-v5.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have all levels of checks prevent recursion
2021-10-20 06:02:58 -10:00
Christoph Hellwig
008f75a20e block: cleanup the flush plug helpers
Consolidate the various helpers into a single blk_flush_plug helper that
takes a plk_plug and the from_scheduler bool and switch all callsites to
call it directly.  Checks that the plug is non-NULL must be performed by
the caller, something that most already do anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211020144119.142582-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-20 09:56:11 -06:00
Eric W. Biederman
32342701b4 ucounts: Use atomic_long_sub_return for clarity
Decrement ucounts using atomic_long_sub_return to make it
clear the point is for the ucount to decrease.

Not a big deal but it should make it easier to catch bugs.

Suggested-by: Yu Zhao <yuzhao@google.com>
Link: https://lkml.kernel.org/r/87k0iaqkqj.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-20 10:45:34 -05:00
Eric W. Biederman
da70d3109e ucounts: Add get_ucounts_or_wrap for clarity
Add a helper function get_ucounts_or_wrap that is a trivial
wrapper around atomic_add_negative, that makes it clear
how atomic_add_negative is used in the context of ucounts.

Link: https://lkml.kernel.org/r/87pms2qkr9.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-20 10:45:34 -05:00
Eric W. Biederman
5fc9e37cd5 ucounts: Remove unnecessary test for NULL ucount in get_ucounts
All of the callers of get_ucounts are passeds a non-NULL value so stop
handling a NULL ucounts pointer in get_ucounts.

It is guaranteed that ever valid fully formed cred that is passed to
commit_cred contains a non-NULL ucounts pointer.  This in turn
gurantees that current_ucounts() never returns NULL.

The call of get_ucounts in user_shm_lock is always passed
current_ucounts().

The call of get_ucounts in mqueue_get_inode is always passed
current_ucounts().

The call of get_ucounts in inc_rlmit_get_ucounts is always
passed iter, after iter has been verified to be non-NULL.

The call of get_ucounts in key_change_session_keyring is always passed
current_ucounts().

The call of get_ucounts in prepare_cred is always passed
current_ucounts().

The call of get_ucounts in prepare_kernel_cred is always
passed task->cred->ucounts or init_cred->ucounts which
being on tasks are guaranteed to have a non-NULL ucounts
field.

Link: https://lkml.kernel.org/r/87v91uqksg.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-20 10:45:34 -05:00
Eric W. Biederman
99c31f9fed ucounts: In set_cred_ucounts assume new->ucounts is non-NULL
Any cred that is destined for use by commit_creds must have a non-NULL
cred->ucounts field.  Only curing credential construction is a NULL
cred->ucounts valid.  Only abort_creds, put_cred, and put_cred_rcu
needs to deal with a cred with a NULL ucount.  As set_cred_ucounts is
non of those case don't confuse people by handling something that can
not happen.

Link: https://lkml.kernel.org/r/871r4irzds.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-20 10:45:34 -05:00
Eric W. Biederman
5ebcbe342b ucounts: Move get_ucounts from cred_alloc_blank to key_change_session_keyring
Setting cred->ucounts in cred_alloc_blank does not make sense.  The
uid and user_ns are deliberately not set in cred_alloc_blank but
instead the setting is delayed until key_change_session_keyring.

So move dealing with ucounts into key_change_session_keyring as well.

Unfortunately that movement of get_ucounts adds a new failure mode to
key_change_session_keyring.  I do not see anything stopping the parent
process from calling setuid and changing the relevant part of it's
cred while keyctl_session_to_parent is running making it fundamentally
necessary to call get_ucounts in key_change_session_keyring.  Which
means that the new failure mode cannot be avoided.

A failure of key_change_session_keyring results in a single threaded
parent keeping it's existing credentials.  Which results in the parent
process not being able to access the session keyring and whichever
keys are in the new keyring.

Further get_ucounts is only expected to fail if the number of bits in
the refernece count for the structure is too few.

Since the code has no other way to report the failure of get_ucounts
and because such failures are not expected to be common add a WARN_ONCE
to report this problem to userspace.

Between the WARN_ONCE and the parent process not having access to
the keys in the new session keyring I expect any failure of get_ucounts
will be noticed and reported and we can find another way to handle this
condition.  (Possibly by just making ucounts->count an atomic_long_t).

Cc: stable@vger.kernel.org
Fixes: 905ae01c4a ("Add a reference to ucounts for each cred")
Link: https://lkml.kernel.org/r/7k0ias0uf.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-20 10:34:20 -05:00
Steven Rostedt (VMware)
91ebe8bcbf tracing/perf: Add interrupt_context_level() helper
Now that there are three different instances of doing the addition trick
to the preempt_count() and NMI_MASK, HARDIRQ_MASK and SOFTIRQ_OFFSET
macros, it deserves a helper function defined in the preempt.h header.

Add the interrupt_context_level() helper and replace the three instances
that do that logic with it.

Link: https://lore.kernel.org/all/20211015142541.4badd8a9@gandalf.local.home/

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-19 20:33:20 -04:00
Steven Rostedt (VMware)
9b84fadc44 tracing: Reuse logic from perf's get_recursion_context()
Instead of having branches that adds noise to the branch prediction, use
the addition logic to set the bit for the level of interrupt context that
the state is currently in. This copies the logic from perf's
get_recursion_context() function.

Link: https://lore.kernel.org/all/20211015161702.GF174703@worktop.programming.kicks-ass.net/

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-19 20:33:20 -04:00
Kalesh Singh
7ce1bb83a1 tracing/cfi: Fix cmp_entries_* functions signature mismatch
If CONFIG_CFI_CLANG=y, attempting to read an event histogram will cause
the kernel to panic due to failed CFI check.

    1. echo 'hist:keys=common_pid' >> events/sched/sched_switch/trigger
    2. cat events/sched/sched_switch/hist
    3. kernel panics on attempting to read hist

This happens because the sort() function expects a generic
int (*)(const void *, const void *) pointer for the compare function.
To prevent this CFI failure, change tracing map cmp_entries_* function
signatures to match this.

Also, fix the build error reported by the kernel test robot [1].

[1] https://lore.kernel.org/r/202110141140.zzi4dRh4-lkp@intel.com/

Link: https://lkml.kernel.org/r/20211014045217.3265162-1-kaleshsingh@google.com

Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-19 20:33:20 -04:00
Steven Rostedt (VMware)
34cdd18b8d tracing: Use linker magic instead of recasting ftrace_ops_list_func()
In an effort to enable -Wcast-function-type in the top-level Makefile to
support Control Flow Integrity builds, all function casts need to be
removed.

This means that ftrace_ops_list_func() can no longer be defined as
ftrace_ops_no_ops(). The reason for ftrace_ops_no_ops() is to use that when
an architecture calls ftrace_ops_list_func() with only two parameters
(called from assembly). And to make sure there's no C side-effects, those
archs call ftrace_ops_no_ops() which only has two parameters, as
ftrace_ops_list_func() has four parameters.

Instead of a typecast, use vmlinux.lds.h to define ftrace_ops_list_func() to
arch_ftrace_ops_list_func() that will define the proper set of parameters.

Link: https://lore.kernel.org/r/20200614070154.6039-1-oscar.carter@gmx.com
Link: https://lkml.kernel.org/r/20200617165616.52241bde@oasis.local.home
Link: https://lore.kernel.org/all/20211005053922.GA702049@embeddedor/

Requested-by: Oscar Carter <oscar.carter@gmx.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-19 20:33:12 -04:00
Kumar Kartikeya Dwivedi
588cd7ef53 bpf: Silence Coverity warning for find_kfunc_desc_btf
The helper function returns a pointer that in the failure case encodes
an error in the struct btf pointer. The current code lead to Coverity
warning about the use of the invalid pointer:

 *** CID 1507963:  Memory - illegal accesses  (USE_AFTER_FREE)
 /kernel/bpf/verifier.c: 1788 in find_kfunc_desc_btf()
 1782                          return ERR_PTR(-EINVAL);
 1783                  }
 1784
 1785                  kfunc_btf = __find_kfunc_desc_btf(env, offset, btf_modp);
 1786                  if (IS_ERR_OR_NULL(kfunc_btf)) {
 1787                          verbose(env, "cannot find module BTF for func_id %u\n", func_id);
 >>>      CID 1507963:  Memory - illegal accesses  (USE_AFTER_FREE)
 >>>      Using freed pointer "kfunc_btf".
 1788                          return kfunc_btf ?: ERR_PTR(-ENOENT);
 1789                  }
 1790                  return kfunc_btf;
 1791          }
 1792          return btf_vmlinux ?: ERR_PTR(-ENOENT);
 1793     }

Daniel suggested the use of ERR_CAST so that the intended use is clear
to Coverity, but on closer look it seems that we never return NULL from
the helper. Andrii noted that since __find_kfunc_desc_btf already logs
errors for all cases except btf_get_by_fd, it is much easier to add
logging for that and remove the IS_ERR check altogether, returning
directly from it.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211009040900.803436-1-memxor@gmail.com
2021-10-19 16:55:50 -07:00
Rafael J. Wysocki
c1bfc59818 Revert "PM: sleep: Do not assume that "mem" is always present"
Revert commit bfcc1e67ff ("PM: sleep: Do not assume that "mem" is
always present"), because it breaks compatibility with user space
utilities assuming that "mem" will always be present in
/sys/power/state.

Fixes: bfcc1e67ff ("PM: sleep: Do not assume that "mem" is always present")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-19 20:59:02 +02:00
Menglong Dong
d25302e465 workqueue: make sysfs of unbound kworker cpumask more clever
Some unfriendly component, such as dpdk, write the same mask to
unbound kworker cpumask again and again. Every time it write to
this interface some work is queue to cpu, even though the mask
is same with the original mask.

So, fix it by return success and do nothing if the cpumask is
equal with the old one.

Signed-off-by: Mengen Sun <mengensun@tencent.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-10-19 08:38:31 -10:00
Eric W. Biederman
34dc2fd6e6 ucounts: Proper error handling in set_cred_ucounts
Instead of leaking the ucounts in new if alloc_ucounts fails, store
the result of alloc_ucounts into a temporary variable, which is later
assigned to new->ucounts.

Cc: stable@vger.kernel.org
Fixes: 905ae01c4a ("Add a reference to ucounts for each cred")
Link: https://lkml.kernel.org/r/87pms2s0v8.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-19 11:04:25 -05:00
Eric W. Biederman
629715adc6 ucounts: Pair inc_rlimit_ucounts with dec_rlimit_ucoutns in commit_creds
The purpose of inc_rlimit_ucounts and dec_rlimit_ucounts in commit_creds
is to change which rlimit counter is used to track a process when the
credentials changes.

Use the same test for both to guarantee the tracking is correct.

Cc: stable@vger.kernel.org
Fixes: 21d1c5e386 ("Reimplement RLIMIT_NPROC on top of ucounts")
Link: https://lkml.kernel.org/r/87v91us0w4.fsf_-_@disp2133
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-19 11:01:52 -05:00
Woody Lin
63acd42c0d sched/scs: Reset the shadow stack when idle_task_exit
Commit f1a0a376ca ("sched/core: Initialize the idle task with
preemption disabled") removed the init_idle() call from
idle_thread_get(). This was the sole call-path on hotplug that resets
the Shadow Call Stack (scs) Stack Pointer (sp).

Not resetting the scs-sp leads to scs overflow after enough hotplug
cycles. Therefore add an explicit scs_task_reset() to the hotplug code
to make sure the scs-sp does get reset on hotplug.

Fixes: f1a0a376ca ("sched/core: Initialize the idle task with preemption disabled")
Signed-off-by: Woody Lin <woodylin@google.com>
[peterz: Changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lore.kernel.org/r/20211012083521.973587-1-woodylin@google.com
2021-10-19 17:46:11 +02:00
Yanfei Xu
5197fcd09a locking/rwsem: Fix comments about reader optimistic lock stealing conditions
After the commit 617f3ef951 ("locking/rwsem: Remove reader
optimistic spinning"), reader doesn't support optimistic spinning
anymore, there is no need meet the condition which OSQ is empty.

BTW, add an unlikely() for the max reader wakeup check in the loop.

Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20211013134154.1085649-4-yanfei.xu@windriver.com
2021-10-19 17:27:06 +02:00
Yanfei Xu
6c2787f2a2 locking: Remove rcu_read_{,un}lock() for preempt_{dis,en}able()
preempt_disable/enable() is equal to RCU read-side crital section, and
the spinning codes in mutex and rwsem could ensure that the preemption
is disabled. So let's remove the unnecessary rcu_read_lock/unlock for
saving some cycles in hot codes.

Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20211013134154.1085649-2-yanfei.xu@windriver.com
2021-10-19 17:27:06 +02:00
Yanfei Xu
7cdacc5f52 locking/rwsem: Disable preemption for spinning region
The spinning region rwsem_spin_on_owner() should not be preempted,
however the rwsem_down_write_slowpath() invokes it and don't disable
preemption. Fix it by adding a pair of preempt_disable/enable().

Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
[peterz: Fix CONFIG_RWSEM_SPIN_ON_OWNER=n build]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20211013134154.1085649-3-yanfei.xu@windriver.com
2021-10-19 17:27:05 +02:00
Peter Zijlstra
4d38167330 futex: Fix PREEMPT_RT build
Mike reported that rcuwait went walk-about and is causing failures on
the PREEMPT_RT builds, restore it.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-10-19 17:27:05 +02:00
Christoph Hellwig
8a7d267b4a block: don't call blk_status_to_errno in blk_update_request
We only need to call it to resolve the blk_status_t -> errno mapping for
tracing, so move the conversion into the tracepoints that are not called
at all when tracing isn't enabled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-19 05:54:57 -06:00
Yonghong Song
223f903e9c bpf: Rename BTF_KIND_TAG to BTF_KIND_DECL_TAG
Patch set [1] introduced BTF_KIND_TAG to allow tagging
declarations for struct/union, struct/union field, var, func
and func arguments and these tags will be encoded into
dwarf. They are also encoded to btf by llvm for the bpf target.

After BTF_KIND_TAG is introduced, we intended to use it
for kernel __user attributes. But kernel __user is actually
a type attribute. Upstream and internal discussion showed
it is not a good idea to mix declaration attribute and
type attribute. So we proposed to introduce btf_type_tag
as a type attribute and existing btf_tag renamed to
btf_decl_tag ([2]).

This patch renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG and some
other declarations with *_tag to *_decl_tag to make it clear
the tag is for declaration. In the future, BTF_KIND_TYPE_TAG
might be introduced per [3].

 [1] https://lore.kernel.org/bpf/20210914223004.244411-1-yhs@fb.com/
 [2] https://reviews.llvm.org/D111588
 [3] https://reviews.llvm.org/D111199

Fixes: b5ea834dde ("bpf: Support for new btf kind BTF_KIND_TAG")
Fixes: 5b84bd1036 ("libbpf: Add support for BTF_KIND_TAG")
Fixes: 5c07f2fec0 ("bpftool: Add support for BTF_KIND_TAG")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211012164838.3345699-1-yhs@fb.com
2021-10-18 18:35:36 -07:00
Gaosheng Cui
d9516f346e audit: return early if the filter rule has a lower priority
It is not necessary for audit_filter_rules() functions to check
audit fileds of the rule with a lower priority, and if we did,
there might be some unintended effects, such as the ctx->ppid
may be changed unexpectedly, so return early if the rule has
a lower priority.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
[PM: slight tweak to the subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-10-18 18:34:37 -04:00
Gaosheng Cui
6e3ee990c9 audit: fix possible null-pointer dereference in audit_filter_rules
Fix  possible null-pointer dereference in audit_filter_rules.

audit_filter_rules() error: we previously assumed 'ctx' could be null

Cc: stable@vger.kernel.org
Fixes: bf361231c2 ("audit: add saddr_fam filter field")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-10-18 18:27:47 -04:00
Steven Rostedt (VMware)
ed65df63a3 tracing: Have all levels of checks prevent recursion
While writing an email explaining the "bit = 0" logic for a discussion on
making ftrace_test_recursion_trylock() disable preemption, I discovered a
path that makes the "not do the logic if bit is zero" unsafe.

The recursion logic is done in hot paths like the function tracer. Thus,
any code executed causes noticeable overhead. Thus, tricks are done to try
to limit the amount of code executed. This included the recursion testing
logic.

Having recursion testing is important, as there are many paths that can
end up in an infinite recursion cycle when tracing every function in the
kernel. Thus protection is needed to prevent that from happening.

Because it is OK to recurse due to different running context levels (e.g.
an interrupt preempts a trace, and then a trace occurs in the interrupt
handler), a set of bits are used to know which context one is in (normal,
softirq, irq and NMI). If a recursion occurs in the same level, it is
prevented*.

Then there are infrastructure levels of recursion as well. When more than
one callback is attached to the same function to trace, it calls a loop
function to iterate over all the callbacks. Both the callbacks and the
loop function have recursion protection. The callbacks use the
"ftrace_test_recursion_trylock()" which has a "function" set of context
bits to test, and the loop function calls the internal
trace_test_and_set_recursion() directly, with an "internal" set of bits.

If an architecture does not implement all the features supported by ftrace
then the callbacks are never called directly, and the loop function is
called instead, which will implement the features of ftrace.

Since both the loop function and the callbacks do recursion protection, it
was seemed unnecessary to do it in both locations. Thus, a trick was made
to have the internal set of recursion bits at a more significant bit
location than the function bits. Then, if any of the higher bits were set,
the logic of the function bits could be skipped, as any new recursion
would first have to go through the loop function.

This is true for architectures that do not support all the ftrace
features, because all functions being traced must first go through the
loop function before going to the callbacks. But this is not true for
architectures that support all the ftrace features. That's because the
loop function could be called due to two callbacks attached to the same
function, but then a recursion function inside the callback could be
called that does not share any other callback, and it will be called
directly.

i.e.

 traced_function_1: [ more than one callback tracing it ]
   call loop_func

 loop_func:
   trace_recursion set internal bit
   call callback

 callback:
   trace_recursion [ skipped because internal bit is set, return 0 ]
   call traced_function_2

 traced_function_2: [ only traced by above callback ]
   call callback

 callback:
   trace_recursion [ skipped because internal bit is set, return 0 ]
   call traced_function_2

 [ wash, rinse, repeat, BOOM! out of shampoo! ]

Thus, the "bit == 0 skip" trick is not safe, unless the loop function is
call for all functions.

Since we want to encourage architectures to implement all ftrace features,
having them slow down due to this extra logic may encourage the
maintainers to update to the latest ftrace features. And because this
logic is only safe for them, remove it completely.

 [*] There is on layer of recursion that is allowed, and that is to allow
     for the transition between interrupt context (normal -> softirq ->
     irq -> NMI), because a trace may occur before the context update is
     visible to the trace recursion logic.

Link: https://lore.kernel.org/all/609b565a-ed6e-a1da-f025-166691b5d994@linux.alibaba.com/
Link: https://lkml.kernel.org/r/20211018154412.09fcad3c@gandalf.local.home

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jisheng Zhang <jszhang@kernel.org>
Cc: =?utf-8?b?546L6LSH?= <yun.wang@linux.alibaba.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: stable@vger.kernel.org
Fixes: edc15cafcb ("tracing: Avoid unnecessary multiple recursion checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-18 18:12:09 -04:00
Eric W. Biederman
15bc01effe ucounts: Fix signal ucount refcounting
In commit fda31c5029 ("signal: avoid double atomic counter
increments for user accounting") Linus made a clever optimization to
how rlimits and the struct user_struct.  Unfortunately that
optimization does not work in the obvious way when moved to nested
rlimits.  The problem is that the last decrement of the per user
namespace per user sigpending counter might also be the last decrement
of the sigpending counter in the parent user namespace as well.  Which
means that simply freeing the leaf ucount in __free_sigqueue is not
enough.

Maintain the optimization and handle the tricky cases by introducing
inc_rlimit_get_ucounts and dec_rlimit_put_ucounts.

By moving the entire optimization into functions that perform all of
the work it becomes possible to ensure that every level is handled
properly.

The new function inc_rlimit_get_ucounts returns 0 on failure to
increment the ucount.  This is different than inc_rlimit_ucounts which
increments the ucounts and returns LONG_MAX if the ucount counter has
exceeded it's maximum or it wrapped (to indicate the counter needs to
decremented).

I wish we had a single user to account all pending signals to across
all of the threads of a process so this complexity was not necessary

Cc: stable@vger.kernel.org
Fixes: d646969055 ("Reimplement RLIMIT_SIGPENDING on top of ucounts")
v1: https://lkml.kernel.org/r/87mtnavszx.fsf_-_@disp2133
Link: https://lkml.kernel.org/r/87fssytizw.fsf_-_@disp2133
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Tested-by: Rune Kleveland <rune.kleveland@infomedia.dk>
Tested-by: Yu Zhao <yuzhao@google.com>
Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-10-18 16:02:30 -05:00
Christoph Hellwig
6a5850d129 sched: move the <linux/blkdev.h> include out of kernel/sched/sched.h
Only core.c needs blkdev.h, so move the #include statement there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Christoph Hellwig
545c6647d2 kernel: remove spurious blkdev.h includes
Various files have acquired spurious includes of <linux/blkdev.h> over
time.  Remove them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Matthew Wilcox (Oracle)
9dd3d06940 mm/filemap: Add filemap_add_folio()
Convert __add_to_page_cache_locked() into __filemap_add_folio().
Add an assertion to it that (for !hugetlbfs), the folio is naturally
aligned within the file.  Move the prototype from mm.h to pagemap.h.
Convert add_to_page_cache_lru() into filemap_add_folio().  Add a
compatibility wrapper for unconverted callers.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
2021-10-18 07:49:40 -04:00
Hamza Mahfooz
c2bbf9d1e9 dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC
Mapping something twice should be possible as long as,
DMA_ATTR_SKIP_CPU_SYNC is passed to the strictly speaking second relevant
mapping operation (that attempts to map the same thing). So, don't issue a
warning if the specified condition is met in add_dma_entry().

Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-10-18 12:46:45 +02:00
Shawn Guo
d46b3f5bc0 reboot: export symbol 'reboot_mode'
Some drivers like Qualcomm pm8941-pwrkey need to access 'reboot_mode'
for triggering reboot between cold and warm mode.  Export the symbol, so
that drivers built as module can still access the symbol.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20210714095850.27185-2-shawn.guo@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2021-10-16 21:31:06 -07:00
Linus Torvalds
368a978cc5 Tracing fixes for 5.15:
- Fix defined but not use warning/error for osnoise function
 
  - Fix memory leak in event probe
 
  - Fix memblock leak in bootconfig
 
  - Fix the API of event probes to be like kprobes
 
  - Added test to check removal of event probe API
 
  - Fix recordmcount.pl for nds32 failed build
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Merge tag 'trace-v5.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Tracing fixes for 5.15:

 - Fix defined but not use warning/error for osnoise function

 - Fix memory leak in event probe

 - Fix memblock leak in bootconfig

 - Fix the API of event probes to be like kprobes

 - Added test to check removal of event probe API

 - Fix recordmcount.pl for nds32 failed build

* tag 'trace-v5.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  nds32/ftrace: Fix Error: invalid operands (*UND* and *UND* sections) for `^'
  selftests/ftrace: Update test for more eprobe removal process
  tracing: Fix event probe removal from dynamic events
  tracing: Fix missing * in comment block
  bootconfig: init: Fix memblock leak in xbc_make_cmdline()
  tracing: Fix memory leak in eprobe_register()
  tracing: Fix missing osnoise tracer on max_latency
2021-10-16 10:51:41 -07:00
Song Liu
79df45731d perf/core: Allow ftrace for functions in kernel/event/core.c
It is useful to trace functions in kernel/event/core.c. Allow ftrace for
them by removing $(CC_FLAGS_FTRACE) from Makefile.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211006210732.2826289-1-songliubraving@fb.com
2021-10-15 11:25:31 +02:00
Adrian Hunter
8b8ff8cc3b perf/x86: Add new event for AUX output counter index
PEBS-via-PT records contain a mask of applicable counters. To identify
which event belongs to which counter, a side-band event is needed. Until
now, there has been no side-band event, and consequently users were limited
to using a single event.

Add such a side-band event. Note the event is optimised to output only
when the counter index changes for an event. That works only so long as
all PEBS-via-PT events are scheduled together, which they are for a
recording session because they are in a single group.

Also no attribute bit is used to select the new event, so a new
kernel is not compatible with older perf tools.  The assumption
being that PEBS-via-PT is sufficiently esoteric that users will not
be troubled by this.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210907163903.11820-2-adrian.hunter@intel.com
2021-10-15 11:25:31 +02:00
Sebastian Andrzej Siewior
09089db798 irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT
On PREEMPT_RT most items are processed as LAZY via softirq context.
Avoid to spin-wait for them because irq_work_sync() could have higher
priority and not allow the irq-work to be completed.

Wait additionally for !IRQ_WORK_HARD_IRQ irq_work items on PREEMPT_RT.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211006111852.1514359-5-bigeasy@linutronix.de
2021-10-15 11:25:18 +02:00
Sebastian Andrzej Siewior
b4c6f86ec2 irq_work: Handle some irq_work in a per-CPU thread on PREEMPT_RT
The irq_work callback is invoked in hard IRQ context. By default all
callbacks are scheduled for invocation right away (given supported by
the architecture) except for the ones marked IRQ_WORK_LAZY which are
delayed until the next timer-tick.

While looking over the callbacks, some of them may acquire locks
(spinlock_t, rwlock_t) which are transformed into sleeping locks on
PREEMPT_RT and must not be acquired in hard IRQ context.
Changing the locks into locks which could be acquired in this context
will lead to other problems such as increased latencies if everything
in the chain has IRQ-off locks. This will not solve all the issues as
one callback has been noticed which invoked kref_put() and its callback
invokes kfree() and this can not be invoked in hardirq context.

Some callbacks are required to be invoked in hardirq context even on
PREEMPT_RT to work properly. This includes for instance the NO_HZ
callback which needs to be able to observe the idle context.

The callbacks which require to be run in hardirq have already been
marked. Use this information to split the callbacks onto the two lists
on PREEMPT_RT:
- lazy_list
  Work items which are not marked with IRQ_WORK_HARD_IRQ will be added
  to this list. Callbacks on this list will be invoked from a per-CPU
  thread.
  The handler here may acquire sleeping locks such as spinlock_t and
  invoke kfree().

- raised_list
  Work items which are marked with IRQ_WORK_HARD_IRQ will be added to
  this list. They will be invoked in hardirq context and must not
  acquire any sleeping locks.

The wake up of the per-CPU thread occurs from irq_work handler/
hardirq context. The thread runs with lowest RT priority to ensure it
runs before any SCHED_OTHER tasks do.

[bigeasy: melt tglx's irq_work_tick_soft() which splits irq_work_tick() into a
	  hard and soft variant. Collected fixes over time from Steven
	  Rostedt and Mike Galbraith. Move to per-CPU threads instead of
	  softirq as suggested by PeterZ.]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211007092646.uhshe3ut2wkrcfzv@linutronix.de
2021-10-15 11:25:17 +02:00
Sebastian Andrzej Siewior
810979682c irq_work: Allow irq_work_sync() to sleep if irq_work() no IRQ support.
irq_work() triggers instantly an interrupt if supported by the
architecture. Otherwise the work will be processed on the next timer
tick. In worst case irq_work_sync() could spin up to a jiffy.

irq_work_sync() is usually used in tear down context which is fully
preemptible. Based on review irq_work_sync() is invoked from preemptible
context and there is one waiter at a time. This qualifies it to use
rcuwait for synchronisation.

Let irq_work_sync() synchronize with rcuwait if the architecture
processes irqwork via the timer tick.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211006111852.1514359-3-bigeasy@linutronix.de
2021-10-15 11:25:17 +02:00