Hello, this patch set fixes problems when buffer heads are discarded under a live filesystem (which can lead to all sorts of issues like crashes in case of ext4). Patch 1 drops some stale buffer invalidation code, patch 2 temporarily gets exclusive access to the block device for the duration of buffer cache handling to avoid interfering with other exclusive bdev user. The patch fixes the problems for me and pass xfstests for ext4. Changes since v1: * Check for exclusive access to the bdev instead of for the presence of superblock Honza
