For a RAID1 device using a file-based bitmap, if a bitmap write error occurs but the later writes succeed, it's possible both BITMAP_STALE and BITMAP_WRITE_ERROR bits will be written to the bitmap super block, the BITMAP_STALE bit will be handled properly and be cleared, but the BITMAP_WRITE_ERROR bit in sb->flags will make bitmap_create() to fail. So clear it to protect against the write failure-and-then-recovery case. Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> --- v2: * clear the BITMAP_WRITE_ERROR bit before writing sb, not after reading sb v1: * http://www.spinics.net/lists/raid/msg59590.html --- drivers/md/bitmap.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index d212163..30e503d 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -459,7 +459,11 @@ void bitmap_update_sb(struct bitmap *bitmap) /* rocking back to read-only */ bitmap->events_cleared = bitmap->mddev->events; sb->events_cleared = cpu_to_le64(bitmap->events_cleared); - sb->state = cpu_to_le32(bitmap->flags); + /* + * clear BITMAP_WRITE_ERROR bit to protect against the case that + * a bitmap write error occurred but the later writes succeeded. + */ + sb->state = cpu_to_le32(bitmap->flags & ~BIT(BITMAP_WRITE_ERROR)); /* Just in case these have been changed via sysfs: */ sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ); sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind); -- 2.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
