Re: [PATCH io_uring-7.2 1/1] io_uring/zcrx: fail non-qops netdevs early

[Jens Axboe <axboe@kernel.dk>]

On 8/6/26 7:49 AM, Jakub Kicinski wrote:
> On Thu, 06 Aug 2026 06:00:49 -0600 Jens Axboe wrote:
>> On Thu, 06 Aug 2026 12:42:33 +0100, Pavel Begunkov wrote:
>>> netdev_get_by_index_lock() might return a netdev that doesn't have qops
>>> and also relies on rtnl. We're going to reject it later when opening a
>>> queue, but netdev_queue_get_dma_dev() warns before that. Reject non-qops
>>> netdevs earlier for now.
>>>
>>> RTNL: assertion failed at ./include/net/netdev_lock.h (72)
>>> WARNING: ./include/net/netdev_lock.h:72 at netdev_assert_locked_ops_compat
>>>     include/net/netdev_lock.h:72 [inline]
>>> WARNING: ./include/net/netdev_lock.h:72 at netdev_queue_get_dma_dev+0x52e/0x660
>>>     net/core/netdev_queues.c:43,
>>> RIP: 0010:netdev_assert_locked_ops_compat include/net/netdev_lock.h:72 [inline]
>>> RIP: 0010:netdev_queue_get_dma_dev+0x53a/0x660 net/core/netdev_queues.c:43
>>> Call Trace:
>>>  <TASK>
>>>  zcrx_register_netdev io_uring/zcrx.c:831 [inline]
>>>  io_register_zcrx+0xe94/0x1d30 io_uring/zcrx.c:983
>>>  __io_uring_register io_uring/register.c:942 [inline]
>>>  __do_sys_io_uring_register+0x1193/0x1bc0 io_uring/register.c:1040
>>>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>>>  do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
>>>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
>>>
>>> [...]  
>>
>> Applied, thanks!
>>
>> [1/1] io_uring/zcrx: fail non-qops netdevs early
>>       commit: cf7aa48151deb629022a8b0c61c139dbfa579933
> 
> I asked for a different fix :/
> 
> https://lore.kernel.org/all/20260805165817.7e1fc367@kernel.org/
> 
> Outside subsystems should not be poking at random fields and making
> guesses. The assert is simply wrong and should be changed.
> 
> Jens, can you drop this please?

Sure, dropped.

-- 
Jens Axboe