From: Lars Ellenberg Date: Wed, 1 Sep 2010 13:12:12 +0000 (+0200) Subject: drbd: fix race on meta-data update X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3f3a9b849d2b703934c07fa17f5eac2dc37c1f6b;p=openwrt%2Fstaging%2Fblogic.git drbd: fix race on meta-data update The race: drbd_md_mark_dirty() drbd_md_sync() if (!test_and_clear_bit(MD_DIRTY, &mdev->flags)) return; drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE) ==> RACE clear_bit(MD_DIRTY, &mdev->flags); <== spurious Fixed by removing the spurious clear_bit. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 23878ffc43c8..73c905d0ef18 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -3446,12 +3446,9 @@ void drbd_md_sync(struct drbd_conf *mdev) D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset); sector = mdev->ldev->md.md_offset; - if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) { - clear_bit(MD_DIRTY, &mdev->flags); - } else { + if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) { /* this was a try anyways ... */ dev_err(DEV, "meta data update failed!\n"); - drbd_chk_io_error(mdev, 1, TRUE); }