Re: [PATCH v3 3/3] genirq: Use the maple tree for IRQ descriptors management

From: Thomas Gleixner
Date: Wed May 10 2023 - 10:41:43 EST


On Wed, May 10 2023 at 15:24, Yujie Liu wrote:
> On Mon, May 08, 2023 at 11:36:37AM +0200, Thomas Gleixner wrote:
>> Ok. So one difference might be that a 64 bit kernel enables interrupt
>> rempping. Can you add 'intremap=off' to the kernel command line please?
> Sorry, my previous info was incorrect.
> The block/008 (do IO while hotplugging CPUs) failure also happens on a
> 64-bit kernel no matter having 'intremap=off' or not, and persists when
> tested against v6.3, but the warning in default_send_IPI_mask_logical
> function is not triggered on a 64-bit kernel. Not sure if that function
> is 32-bit specific since it is set in arch/x86/kernel/apic/probe_32.c.

Ok. That makes more sense as the issue is clearly independent of 32 or
64 bit.

I decoded it by now and that maple_tree conversion is the culprit. It
broke irq_get_next_irq() which is used during hotplug. It misses every
other interrupt, so affinities are not fixed up.

Please ignore that series.

Thanks a lot for your help!