From: Neil Brown Date: Fri, 27 Jun 2008 22:31:14 +0000 (+1000) Subject: Don't acknowlege that stripe-expand is complete until it really is. X-Git-Tag: v2.6.26-rc9~82^2~1 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=efe311431869b40d67911820a309f9a1a41306f3;p=linux-2.6 Don't acknowlege that stripe-expand is complete until it really is. We shouldn't acknowledge that a stripe has been expanded (When reshaping a raid5 by adding a device) until the moved data has actually been written out. However we are currently acknowledging (by calling md_done_sync) when the POST_XOR is complete and before the write. So track in s.locked whether there are pending writes, and don't call md_done_sync yet if there are. Note: we all set R5_LOCKED on devices which are are about to read from. This probably isn't technically necessary, but is usually done when writing a block, and justifies the use of s.locked here. This bug can lead to a crash if an array is stopped while an reshape is in progress. Cc: Signed-off-by: Neil Brown --- diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 475fba4d37..54c8ee28fc 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2898,6 +2898,8 @@ static void handle_stripe5(struct stripe_head *sh) for (i = conf->raid_disks; i--; ) { set_bit(R5_Wantwrite, &sh->dev[i].flags); + set_bit(R5_LOCKED, &dev->flags); + s.locked++; if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) sh->ops.count++; } @@ -2911,6 +2913,7 @@ static void handle_stripe5(struct stripe_head *sh) conf->raid_disks); s.locked += handle_write_operations5(sh, 1, 1); } else if (s.expanded && + s.locked == 0 && !test_bit(STRIPE_OP_POSTXOR, &sh->ops.pending)) { clear_bit(STRIPE_EXPAND_READY, &sh->state); atomic_dec(&conf->reshape_stripes);