diff options
author | Mark Rutland <mark.rutland@arm.com> | 2021-11-29 14:06:48 +0100 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2021-12-01 00:06:44 +0100 |
commit | 342b3808786518ced347f40b59bae68664e20007 (patch) | |
tree | 606e6ea97e7e8dfdaabee98e6e071d8176d830b7 /arch/arm64/kernel/entry-common.c | |
parent | ARM: Snapshot thread flags (diff) | |
download | linux-342b3808786518ced347f40b59bae68664e20007.tar.xz linux-342b3808786518ced347f40b59bae68664e20007.zip |
arm64: Snapshot thread flags
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>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20211129130653.2037928-7-mark.rutland@arm.com
Diffstat (limited to 'arch/arm64/kernel/entry-common.c')
-rw-r--r-- | arch/arm64/kernel/entry-common.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index f7408edf8571..ef7fcefb96bd 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -129,7 +129,7 @@ static __always_inline void prepare_exit_to_user_mode(struct pt_regs *regs) local_daif_mask(); - flags = READ_ONCE(current_thread_info()->flags); + flags = read_thread_flags(); if (unlikely(flags & _TIF_WORK_MASK)) do_notify_resume(regs, flags); } |