From: Jeff Mahoney Date: Wed, 1 Aug 2018 22:06:45 +0000 (-0500) Subject: mkfs: avoid divide-by-zero when hardware reports optimal i/o size as 0 X-Git-Tag: v4.18.0-rc1~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=99a3f52e337d9c785315e64a599755bc6f7b2118;p=thirdparty%2Fxfsprogs-dev.git mkfs: avoid divide-by-zero when hardware reports optimal i/o size as 0 Commit 051b4e37f5e (mkfs: factor AG alignment) factored out the AG alignment code into a separate function. It got rid of redundant checks for dswidth != 0 since calc_stripe_factors was supposed to guarantee that if dsunit is non-zero dswidth will be as well. Unfortunately, there's hardware out there that reports its optimal i/o size as larger than the maximum i/o size, which the kernel treats as broken and zeros out the optimal i/o size. To resolve this we can check the topology before consuming it, and ignore the bad stripe geometry. Fixes: 051b4e37f5e (mkfs: factor AG alignment) Signed-off-by: Jeff Mahoney Reviewed-by: Eric Sandeen [sandeen: remove guessing heuristic, just warn and ignore bad data.] Reviewed-by: Jeff Mahoney Signed-off-by: Eric Sandeen --- diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c index 1074886a0..2e53c1e83 100644 --- a/mkfs/xfs_mkfs.c +++ b/mkfs/xfs_mkfs.c @@ -2281,11 +2281,20 @@ _("data stripe width (%d) must be a multiple of the data stripe unit (%d)\n"), /* if no stripe config set, use the device default */ if (!dsunit) { - dsunit = ft->dsunit; - dswidth = ft->dswidth; - use_dev = true; + /* Ignore nonsense from device. XXX add more validation */ + if (ft->dsunit && ft->dswidth == 0) { + fprintf(stderr, +_("%s: Volume reports stripe unit of %d bytes and stripe width of 0, ignoring.\n"), + progname, BBTOB(ft->dsunit)); + ft->dsunit = 0; + ft->dswidth = 0; + } else { + dsunit = ft->dsunit; + dswidth = ft->dswidth; + use_dev = true; + } } else { - /* check and warn is alignment is sub-optimal */ + /* check and warn if user-specified alignment is sub-optimal */ if (ft->dsunit && ft->dsunit != dsunit) { fprintf(stderr, _("%s: Specified data stripe unit %d is not the same as the volume stripe unit %d\n"),