On Wed, 9 Jan 2019 at 14:43, Mark Syms <mark.s...@citrix.com> wrote:
> We don't yet know how the assert got triggered as we've only seen it once
> and in the original form it looks like it would be very hard to trigger in
> any normal case (given that in default usage i_blocks should be at least 8
> times what any putative value for change could be). So, for the assert to
> have triggered we've been asked to remove at least 8 times the number of
> blocks currently allocated to the inode. Possible causes could be a double
> release or some other higher level bug that will require further
> investigation to uncover.
>
The following change has at least survived xfstests:
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -61,8 +61,8 @@ static inline u64 gfs2_get_inode_blocks(const struct
inode *inode)
static inline void gfs2_add_inode_blocks(struct inode *inode, s64 change)
{
- gfs2_assert(GFS2_SB(inode), (change >= 0 || inode->i_blocks >
-change));
- change *= (GFS2_SB(inode)->sd_sb.sb_bsize/GFS2_BASIC_BLOCK);
+ change <<= inode->i_blkbits - 9;
+ gfs2_assert(GFS2_SB(inode), change >= 0 || inode->i_blocks >= -change);
inode->i_blocks += change;
}
Andreas
