Commit 4ea7ce0a authored by Mark Rutland's avatar Mark Rutland Committed by Thomas Gleixner
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openrisc: 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: default avatarMark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarStafford Horne <shorne@gmail.com>
Acked-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Link: https://lore.kernel.org/r/20211129130653.2037928-9-mark.rutland@arm.com
parent e538c584

arch/openrisc/kernel/signal.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

}