On Wed, Jul 22 2020 at 2:46pm -0400, Mikulas Patocka <[email protected]> wrote:
> Hi Mike > > Please submit this to Linus and to RHEL-8. > > Mikulas > > > > From: Mikulas Patocka <[email protected]> > > The patch adc0daad366b62ca1bce3e2958a40b0b71a8b8b3 broke recalculation on > dm-integrity. The patch replaces a private variable "suspending" with a > call to "dm_suspended". > > The problem is that dm_suspended returns true not only during suspend, but > also during resume. This race condition could occur: > 1. dm_integrity_resume calls queue_work(ic->recalc_wq, &ic->recalc_work) > 2. integrity_recalc (&ic->recalc_work) preempts the current thread > 3. integrity_recalc calls if (unlikely(dm_suspended(ic->ti))) goto unlock_ret; > 4. integrity_recalc exits and no recalculating is done. > > In order to fix this race condition, we stop using dm_suspended and start > using the variable "suspending" (that is only set during suspend, not > during resume). > > Signed-off-by: Mikulas Patocka <[email protected]> > Fixes: adc0daad366b ("dm: report suspended device during destroy") > Cc: [email protected] # v4.18+ OK, but why not add a dm_suspending() to DM core? Could be other future targets would like this same info right? I don't see harm in elevating it. Mike -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
