On Thu, Jul 19, 2018 at 05:23:22PM -0400, Jeff Mahoney wrote: > 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. We'll accept > the multi-sector dsunit but have a zero dswidth and hit a divide-by-zero > in align_ag_geometry. > > To resolve this we can check the topology before consuming it, default > to using the stripe unit as the stripe width, and warn the user about it. > I wonder if this shouldn't go into blkid_get_topology since something is wrong with the information reported by the storage. And require a force_overwrite to continue, at this point, something looks quite wrong in the storage, and I think this is the last 'resource' a sysadmin will have to notice this before making the FS, and start using it, so, maybe requiring force_overwrite would bring more attention. > Fixes: 051b4e37f5e (mkfs: factor AG alignment) > Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx> > --- > mkfs/xfs_mkfs.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c > index a135e06e..35542e57 100644 > --- a/mkfs/xfs_mkfs.c > +++ b/mkfs/xfs_mkfs.c > @@ -2295,6 +2295,12 @@ _("data stripe width (%d) must be a multiple of the data stripe unit (%d)\n"), > if (!dsunit) { > dsunit = ft->dsunit; > dswidth = ft->dswidth; > + if (dsunit && dswidth == 0) { > + fprintf(stderr, > +_("%s: Volume reports stripe unit of %d bytes but stripe width of 0. Using stripe width of %d bytes, which may not be optimal.\n"), > + progname, dsunit << 9, dsunit << 9); > + dswidth = dsunit; > + } > use_dev = true; > } else { > /* check and warn is alignment is sub-optimal */ > -- > 2.16.4 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Carlos -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html