Re: [Intel-wired-lan] ice crashes when not enough IRQs

[Tony Nguyen <anthony.l.nguyen@intel.com>]

On 3/15/2026 1:22 PM, Jakub Kicinski wrote:
> On Sun, 15 Mar 2026 13:01:50 -0700 Jakub Kicinski wrote:
>> On Sun, 15 Mar 2026 12:54:51 -0700 Jakub Kicinski wrote:
>>> Trying to build a minimal kernel I dropped CONFIG_IRQ_REMAP=y from
>>> my config, and (on AMD) that caused IRQ shortage.
>>>
>>> This seems to crash ice after commit ad61cd9c67ad ("ice: get rid of
>>> num_lan_msix field"). Sorry for the lack of line numbers, I also
>>> dropped DEBUG_INFO. But I think the problem itself is pretty obvious.
>>> The fix less so, short of reverting ad61cd9c67ad. We can't just clamp
>>> the queues in ice_vsi_alloc_q_vectors() because AFAICT that would make
>>> ethtool -L succeed but driver would have a lower queue count than
>>> requested.
>>
>> Hm, maybe it's not just CONFIG_IRQ_REMAP=y
>> Enabling it makes no difference. Let me try to see what state the IRQ
>> allocation machinery is in on this kernel. On distro kernel ice gets
>> all the IRQs it wants at boot. But it also barfs something RDMA so
>> I can't really compare..
> 
> I think it's ee13aa1a2c5a ("ice: use netif_get_num_default_rss_queues()")
> It clamped the number of allocated queues but I think it meant to only
> clamp the default enabled queue count. No idea how y'all gonna get the
> extra IRQs later or whether you intended to pack multiple queues per IRQ
> so I'll let you figure this out..

Hi Jakub,

Thanks for letting us know. I think we have the fix for this in the 
pipeline [1]. I'll try to get it tested and out to you ASAP.

Thanks,
Tony

[1] 
https://lore.kernel.org/intel-wired-lan/20260223125157.819135-1-michal.swiatkowski@linux.intel.com/

> Thanks for letting me test crash detection and recovery in NIPA, I guess :D