Messages in this thread Patch in this message | | | From | Mark Rutland <> | Subject | [PATCHv7 04/11] alpha: snapshot thread flags | Date | Wed, 17 Nov 2021 16:30:42 +0000 |
| |
Some thread flags can be set remotely, and so even when IRQs are disabled, the flags can change under our feet. Generally this is unlikely to cause a problem in practice, but it is somewhat unsound, and KCSAN will legitimately warn that there is a data race.
To avoid such issues, a snapshot of the flags has to be taken prior to using them. Some places already use READ_ONCE() for that, others do not.
Convert them all to the new flag accessor helpers.
Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Richard Henderson <rth@twiddle.net> --- arch/alpha/kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c index bc077babafab..d8ed71d5bed3 100644 --- a/arch/alpha/kernel/signal.c +++ b/arch/alpha/kernel/signal.c @@ -535,6 +535,6 @@ do_work_pending(struct pt_regs *regs, unsigned long thread_flags, } } local_irq_disable(); - thread_flags = current_thread_info()->flags; + thread_flags = read_thread_flags(); } while (thread_flags & _TIF_WORK_MASK); } -- 2.11.0
| |