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Subject[PATCHv7 08/11] openrisc: snapshot thread flags
Date
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: Stafford Horne <shorne@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
---
arch/openrisc/kernel/signal.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
index 99516c9191c7..92c5b70740f5 100644
--- a/arch/openrisc/kernel/signal.c
+++ b/arch/openrisc/kernel/signal.c
@@ -313,7 +313,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
}
}
local_irq_disable();
- thread_flags = current_thread_info()->flags;
+ thread_flags = read_thread_flags();
} while (thread_flags & _TIF_WORK_MASK);
return 0;
}
--
2.11.0
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