On Fri, Oct 13, 2017 at 06:36:31PM +0800, Hou Tao wrote: > For a RAID1 device using a file-based bitmap, if a bitmap write error > occurs and the later writes succeed, it's possible both BITMAP_STALE > and BITMAP_WRITE_ERROR bit will be written to the bitmap super block, > and the BITMAP_WRITE_ERROR bit in sb->flags will make bitmap_create() > to fail. Why don't clear the bit in the 'latter succeeded write'? > So clear it to protect against the write failure-success case. > > Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> > --- > drivers/md/bitmap.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c > index d212163..97c423a 100644 > --- a/drivers/md/bitmap.c > +++ b/drivers/md/bitmap.c > @@ -688,8 +688,13 @@ static int bitmap_read_sb(struct bitmap *bitmap) > } > } > > - /* assign fields using values from superblock */ > - bitmap->flags |= le32_to_cpu(sb->state); > + /* > + * assign fields using values from superblock > + * clear BITMAP_WRITE_ERROR bit to protect against the case that > + * a bitmap write error had occurred and the later writes had > + * succeeded. > + */ > + bitmap->flags |= (le32_to_cpu(sb->state) & ~BIT(BITMAP_WRITE_ERROR)); > if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN) > set_bit(BITMAP_HOSTENDIAN, &bitmap->flags); > bitmap->events_cleared = le64_to_cpu(sb->events_cleared); > -- > 2.5.0 > -- 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
