While the fsstress background writes are busy dirtying the page cache, if a fsfreeze happens then the background writes should stall. A sync should then not have any data to sync to the FS. If it does have any data to sync then sync will cause a deadlock by holding the s_umount write semaphore and waiting in the wait queue for the FS to thaw, whereas the F.S can never thaw without getting the s_umount write semaphore. Signed-off-by: Surbhi Palande <surbhi.palande@xxxxxxxxxxxxx> --- 068 | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/068 b/068 index 82c1a4e..b9ac58d 100755 --- a/068 +++ b/068 @@ -101,6 +101,11 @@ do tee -a $seq.full sleep 2 + # there should be nothing to sync at this point. This may hang in case + # of fsstress background writes dirtying the page cache while the F.S is frozen + sync & + sleep 2 + echo "*** thawing \$SCRATCH_MNT" | tee -a $seq.full xfs_freeze -u "$SCRATCH_MNT" | tee -a $seq.full [ $? != 0 ] && echo xfs_freeze -u "$SCRATCH_MNT" failed | \ -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
