On Tue, May 03, 2016 at 03:38:03PM +0200, Johannes Thumshirn wrote: > Inititialize the hd_struct's perpcu reference before assigning the hd_struct > to the partition table list. > > This fixes a race which could be triggered using a simple partition > creation/deletion loop with virtio-blk on aarch64. > > Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx> > --- > block/partition-generic.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/block/partition-generic.c b/block/partition-generic.c > index 5d87019..aa5b83a 100644 > --- a/block/partition-generic.c > +++ b/block/partition-generic.c > @@ -361,6 +361,10 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno, > goto out_del; > } > > + err = -ENOMEM; > + if (hd_ref_init(p)) > + goto out_free_info; > + > /* everything is up and running, commence */ > rcu_assign_pointer(ptbl->part[partno], p); > > @@ -368,8 +372,7 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno, > if (!dev_get_uevent_suppress(ddev)) > kobject_uevent(&pdev->kobj, KOBJ_ADD); > > - if (!hd_ref_init(p)) > - return p; > + return p; > > out_free_info: > free_part_info(p); > -- > 1.8.5.2 > We've just seen that this is already fixed with b30a337ca 'block: partition: initialize percpuref before sending out KOBJ_ADD' Sorry for the noise, Johannes -- Johannes Thumshirn Storage jthumshirn@xxxxxxx +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html