Frederic Weisbecker 8f6b943f9f entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up ... [ Upstream commit b416514054 ] RCU sometimes needs to perform a delayed wake up for specific kthreads handling offloaded callbacks (RCU_NOCB). These wakeups are performed by timers and upon entry to idle (also to guest and to user on nohz_full). However the delayed wake-up on kernel exit is actually performed after the thread flags are fetched towards the fast path check for work to do on exit to user. As a result, and if there is no other pending work to do upon that kernel exit, the current task will resume to userspace with TIF_RESCHED set and the pending wake up ignored. Fix this with fetching the thread flags _after_ the delayed RCU-nocb kthread wake-up. Fixes: 47b8ff194c ("entry: Explicitly flush pending rcuog wakeup before last rescheduling point") Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230315194349.10798-3-joel@joelfernandes.org Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-03-30 12:47:51 +02:00
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common.c	entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up	2023-03-30 12:47:51 +02:00
common.h	kernel: Implement selective syscall userspace redirection	2020-12-02 15:07:56 +01:00
kvm.c	entry: Snapshot thread flags	2023-03-30 12:47:50 +02:00
Makefile	kernel: Implement selective syscall userspace redirection	2020-12-02 15:07:56 +01:00
syscall_user_dispatch.c	signal: Replace force_fatal_sig with force_exit_sig when in doubt	2021-11-25 09:49:07 +01:00