On Mon, Feb 22, 2021 at 08:20:38PM +0800, Zhengyejian (Zetta) wrote: > > > On 2021/2/22 20:07, Greg KH wrote: > > On Mon, Feb 22, 2021 at 11:54:24AM +0000, Lee Jones wrote: > > > On Mon, 22 Feb 2021, Zheng Yejian wrote: > > > > > > > From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > > > > > > > commit a97cb0e7b3f4c6297fd857055ae8e895f402f501 upstream. > > > > > > > > Both Geert and DaveJ reported that the recent futex commit: > > > > > > > > c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex") > > > > > > > > introduced a problem with setting OWNER_DEAD. We set the bit on an > > > > uninitialized variable and then entirely optimize it away as a > > > > dead-store. > > > > > > > > Move the setting of the bit to where it is more useful. > > > > > > > > Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > > > > Reported-by: Dave Jones <davej@xxxxxxxxxxxxxxxxx> > > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > > > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > > > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > > > Cc: Paul E. McKenney <paulmck@xxxxxxxxxx> > > > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > > > Fixes: c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex") > > > > Link: http://lkml.kernel.org/r/20180122103947.GD2228@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx > > > > Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> > > > > Signed-off-by: Zheng Yejian <zhengyejian1@xxxxxxxxxx> > > > > --- > > > > kernel/futex.c | 7 +++---- > > > > 1 file changed, 3 insertions(+), 4 deletions(-) > > > > > > Reviewed-by: Lee Jones <lee.jones@xxxxxxxxxx> > > > > This does not apply to the 4.9.y tree at all right now, are you all sure > > you got the backport correct? > > > > confused, > > > > greg k-h > > . > > > I make the patch basing on 282aeb477a10 ("Linux 4.9.257"). > Should I base on f0cf73f13b39 ("Linux 4.9.258-rc1")? Yes please as I think this is already there. How about just waiting for the next release to come out, I will push out the 4.4 and 4.9 -rc releases right now as well to give everyone a chance to sync up properly. thanks, greg k-h