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| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2024-07-04 19:03:36 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-01 01:58:20 +0100 |
| commit | 380681a29066c1f5402053f62862931f1cf6b305 (patch) | |
| tree | 2ee27df27ba45527a11411520d0eda858e44cee3 /include | |
| parent | a3fe89d4f5bb12791e4407542385b39bde55fc39 (diff) | |
| download | linux-380681a29066c1f5402053f62862931f1cf6b305.tar.gz linux-380681a29066c1f5402053f62862931f1cf6b305.tar.bz2 linux-380681a29066c1f5402053f62862931f1cf6b305.zip | |
task_work: Add TWA_NMI_CURRENT as an additional notify mode.
[ Upstream commit 466e4d801cd438a1ab2c8a2cce1bef6b65c31bbb ]
Adding task_work from NMI context requires the following:
- The kasan_record_aux_stack() is not NMU safe and must be avoided.
- Using TWA_RESUME is NMI safe. If the NMI occurs while the CPU is in
userland then it will continue in userland and not invoke the `work'
callback.
Add TWA_NMI_CURRENT as an additional notify mode. In this mode skip
kasan and use irq_work in hardirq-mode to for needed interrupt. Set
TIF_NOTIFY_RESUME within the irq_work callback due to k[ac]san
instrumentation in test_and_set_bit() which does not look NMI safe in
case of a report.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240704170424.1466941-3-bigeasy@linutronix.de
Stable-dep-of: 73ab05aa46b0 ("sched/core: Disable page allocation in task_tick_mm_cid()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/task_work.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/task_work.h b/include/linux/task_work.h index 26b8a47f41fc..cf5e7e891a77 100644 --- a/include/linux/task_work.h +++ b/include/linux/task_work.h @@ -18,6 +18,7 @@ enum task_work_notify_mode { TWA_RESUME, TWA_SIGNAL, TWA_SIGNAL_NO_IPI, + TWA_NMI_CURRENT, }; static inline bool task_work_pending(struct task_struct *task) |