On Tue, Jul 09, 2019 at 07:22:26AM -0700, Darrick J. Wong wrote: > On Tue, Jul 09, 2019 at 06:59:43AM -0700, Darrick J. Wong wrote: > > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > > > There's a subtle unit conversion error when we increment the INUMBERS > > cursor at the end of xfs_inumbers_walk. If there's an inode chunk at > > the very end of the AG /and/ the AG size is a perfect power of two, that > > means we can have inodes, that means that the startino of that last > > "...is a perfect power of two, the startino of that last chunk..." > Yeah, was going to point out this looked like some stale/spurious text... :P > --D > > > chunk (which is in units of AG inodes) will be 63 less than (1 << > > agino_log). If we add XFS_INODES_PER_CHUNK to the startino, we end up > > with a startino that's larger than (1 << agino_log) and when we convert > > that back to fs inode units we'll rip off that upper bit and wind up > > back at the start of the AG. > > > > Fix this by converting to units of fs inodes before adding > > XFS_INODES_PER_CHUNK so that we'll harmlessly end up pointing to the > > next AG. > > > > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > --- Otherwise looks good: Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> > > fs/xfs/xfs_itable.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c > > index cda8ae94480c..a8a06bb78ea8 100644 > > --- a/fs/xfs/xfs_itable.c > > +++ b/fs/xfs/xfs_itable.c > > @@ -338,15 +338,14 @@ xfs_inumbers_walk( > > .xi_version = XFS_INUMBERS_VERSION_V5, > > }; > > struct xfs_inumbers_chunk *ic = data; > > - xfs_agino_t agino; > > int error; > > > > error = ic->formatter(ic->breq, &inogrp); > > if (error && error != XFS_IBULK_ABORT) > > return error; > > > > - agino = irec->ir_startino + XFS_INODES_PER_CHUNK; > > - ic->breq->startino = XFS_AGINO_TO_INO(mp, agno, agino); > > + ic->breq->startino = XFS_AGINO_TO_INO(mp, agno, irec->ir_startino) + > > + XFS_INODES_PER_CHUNK; > > return error; > > } > >
