We don't have any debug symbols but here is a dump of the .ko at this address: https://gist.github.com/hannes-landeholm/b4664e2e7e37ad13177c It's likely this line (rbd_dev_refresh+0xcb) 3d5b: 4c 89 60 50 mov %r12,0x50(%rax) %rax here is null which causes the invalid write to address 0000000000000050. I'm pretty sure it's the following line in rbd.c which is the offender if you look at the context (below spinlock and shr, above call to revalidate_disk). set_capacity(rbd_dev->disk, size); https://github.com/torvalds/linux/blob/e69b8d414f948c242ad9f3eb2b7e24fba783dbbd/drivers/block/rbd.c#L3682 -- Hannes Landeholm -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html