On Wed, Oct 11, 2017 at 05:17:56PM +0000, Bart Van Assche wrote: > On Tue, 2017-10-10 at 18:48 -0700, Shaohua Li wrote: > > The problem is __md_stop_writes set some bit like MD_RECOVERY_FROZEN, which > > will prevent md_check_recovery restarting resync/reshape. I think we need > > preserve mddev->recovery in suspend prepare and restore after resume > > Hello Shaohua, > > As far as I can see __md_stop_writes() sets MD_RECOVERY_FROZEN and can set > MD_RECOVERY_INTR. Since md_check_recovery() clears MD_RECOVERY_INTR I think > it should be sufficient to save and restore the state of the > MD_RECOVERY_FROZEN flag. However, when I ran the following test: > * echo frozen > /sys/block/md0/md/sync_action > * cat /sys/block/md0/md/sync_action > * systemctl hibernate > * (power on system again) > * cat /sys/block/md0/md/sync_action > > the output that appeared was as follows: > > frozen > idle > Does that mean that a hibernate or suspend followed by a resume is sufficient > to clear the MD_RECOVERY_FROZEN flag for the md drivers and hence that the > patch at the start of this e-mail thread does not need any further > modifications? Have no idea why it shows 'idle'. From my understanding, after resume, previous memory is stored and MD_RECOVERY_FROZEN bit should be set. Was trying to understand what happens. Thanks, Shaohua
