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X-MS-Exchange-CrossTenant-Id: b61c8803-16f3-4c35-9b17-6f65f441df86 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 48xU7lClMSQecmH8SYqMmtU/3zkyBDZrBmCV9e65ucbV+h2ZMgQJjkTucw8G2yqN2h78l2UU+SqsENhKBDdTLQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DSVPR04MB993550 On 31/08/2026 09:10, Christoph Hellwig wrote: > On Thu, Aug 27, 2026 at 01:28:55PM +0200, Hans Holmberg wrote: >> mkfs probes the device topology before libxfs_init opens the target. >> If blkid cannot open the device, blkid_new_probe_from_filename returns >> NULL and leaves the topology sector sizes initialized to zero. This >> causes mkfs to report the misleading error "illegal sector size 0". >> >> Report the underlying open error immediately so that permission >> failures are diagnosed correctly. For example: >> >> cannot probe device topology for device /dev/nvme1n1: Permission denied > > Did you also accidentally run mkfs as a regular users? :) That's how > I ran into this, but didn't get around fixing it. Yeah, I do this all the time and became so annoyed with the wierd error message i had to fix it :) > >> >> Signed-off-by: Hans Holmberg >> --- >> libxfs/topology.c | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/libxfs/topology.c b/libxfs/topology.c >> index dc2aaa17..5571c9d8 100644 >> --- a/libxfs/topology.c >> +++ b/libxfs/topology.c >> @@ -230,8 +230,12 @@ blkid_get_topology( >> blkid_probe pr; >> >> pr = blkid_new_probe_from_filename(device); >> - if (!pr) >> - return; >> + if (!pr) { >> + fprintf(stderr, >> + _("cannot probe device topology for device %s: %s\n"), >> + device, strerror(errno)); >> + exit(EXIT_FAILURE); >> + } > > I wonder if there are any valid failures from blkid_new_probe_from_filename > where we'd want to continue? Probably not as it doesn't really have an > obvious failure path, but so far we continue here. So the print is useful > for sure, but I wonder if failing here might cause regressions in some > really odd use case (containers without sysfs? Although we'd run into > trouble with that quickly in other places). Yeah, it might be safer to just print the warning, and that would solve my problem (no instructive error message), On the other hand it's nice to fail early - but not if it causes regressions of course.