On Fri 12-08-22 14:42:36, Jeff Layton wrote: > On Fri, 2022-08-12 at 14:37 +0200, Lukas Czerner wrote: > > ea_inodes are using i_version for storing part of the reference count so > > we really need to leave it alone. > > > > The problem can be reproduced by xfstest ext4/026 when iversion is > > enabled. Fix it by not calling inode_inc_iversion() for EXT4_EA_INODE_FL > > inodes in ext4_mark_iloc_dirty(). > > > > Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx> > > Reviewed-by: Jan Kara <jack@xxxxxxx> > > Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> > > --- > > v2, v3: no change > > > > fs/ext4/inode.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > > index 601214453c3a..2a220be34caa 100644 > > --- a/fs/ext4/inode.c > > +++ b/fs/ext4/inode.c > > @@ -5731,7 +5731,12 @@ int ext4_mark_iloc_dirty(handle_t *handle, > > } > > ext4_fc_track_inode(handle, inode); > > > > - if (IS_I_VERSION(inode)) > > + /* > > + * ea_inodes are using i_version for storing reference count, don't > > + * mess with it > > + */ > > + if (IS_I_VERSION(inode) && > > + !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) > > inode_inc_iversion(inode); > > > > /* the do_update_inode consumes one bh->b_count */ > > > I've spent some time writing tests for the i_version counter (still > quite rough right now), and what I've found is that this particular > inode_inc_iversion results in the counter being bumped on _reads_ as > well as writes, due to the atime changing. This call to > inode_inc_iversion seems to make no sense, as we aren't bumping the > mtime here. > > I'm still working on and testing this, but I think we'll probably just > want to remove this inode_inc_iversion entirely, and leave the i_version > bumping for normal files to happen when the timestamps are updated. So > far, my testing seems to indicate that that does the right thing. I agree that inode_inc_iversion() may be overly agressive here but where else does get iversion updated for things like inode owner update or permission changes? Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
