On Tue, 14 Mar 2023 11:06:25 +1100 "NeilBrown" <neilb@xxxxxxx> wrote: > mdopen() will use create_named_array() to ask the kernel to create the > given md array, but only if it is given a number or name. > If it is NOT given a name and is required to choose one itself using > find_free_devnm() it does NOT use create_named_array(). > > On kernels with CONFIG_BLOCK_LEGACY_AUTOLOAD not set, this can result in > failure to assemble an array. This can particularly seen when the > "name" of the array begins with a host name different to the name of the > host running the command. > > So add the missing call to create_named_array(). > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217074 > Signed-off-by: NeilBrown <neilb@xxxxxxx> > --- > mdopen.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mdopen.c b/mdopen.c > index d18c931996d2..810f79a3d19a 100644 > --- a/mdopen.c > +++ b/mdopen.c > @@ -370,6 +370,7 @@ int create_mddev(char *dev, char *name, int autof, int > trustworthy, } > if (block_udev) > udev_block(devnm); > + create_named_array(devnm); > } > > sprintf(devname, "/dev/%s", devnm); Hi Neil, Thanks for handling that. I didn't have time to get into this topic yet. I trust you and I believe that it is a good fix but I cannot verify it by standard code review- the code is to complex. Could you please add test for it to prove it works this way at least for following cases? - mdadm -CR /dev/md/name - mdadm -CR name - mdadm -CR /dev/md_name - mdadm -CR /dev/mdX, where X is a number. You can disable creation via open temporarily by changing value in /sys/module/md_mod/parameters/new_array that should be enough for verification. For code: Acked-by: Mariusz Tkaczyk <mariusz.tkaczyk@xxxxxxxxxxxxxxx> Thanks, Mariusz
