From: Ed Cashin Date: Tue, 18 Dec 2012 00:03:47 +0000 (-0800) Subject: aoe: manipulate aoedev network stats under lock X-Git-Tag: firefly_0821_release~3680^2~1415^2~42 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0d555ecfa468f6dc29697829844f2f79909e376f;p=firefly-linux-kernel-4.4.55.git aoe: manipulate aoedev network stats under lock With this bugfix in place the calculation of the criterion for "lateness" is performed under lock. Without the lock, there is a chance that one of the non-atomic operations performed on the round trip time statistics could be incomplete, such that an incorrect lateness criterion would be calculated. Without this change, the effect of the bug would be rare unecessary but benign retransmissions. Signed-off-by: Ed Cashin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c index 6ea27fd8954d..9aefbe3957ca 100644 --- a/drivers/block/aoe/aoecmd.c +++ b/drivers/block/aoe/aoecmd.c @@ -603,14 +603,14 @@ rexmit_timer(ulong vp) d = (struct aoedev *) vp; + spin_lock_irqsave(&d->lock, flags); + /* timeout based on observed timings and variations */ timeout = 2 * d->rttavg >> RTTSCALE; timeout += 8 * d->rttdev >> RTTDSCALE; if (timeout == 0) timeout = 1; - spin_lock_irqsave(&d->lock, flags); - if (d->flags & DEVFL_TKILL) { spin_unlock_irqrestore(&d->lock, flags); return;