Re: [PATCH v2 1/3] irqdomain: simplify simple and legacy domain creation

["Jiaxun Yang" <jiaxun.yang@flygoat.com>]

在2024年8月13日八月 上午11:54，Matti Vaittinen写道：
[...]
>> This might be caused by drivers/irqchip/irq-mips-cpu.c has 
>> irq_domain_add_legacy() called with
>> first_irq set to 0.

>> 
>
> Right. Thanks for the report! I do appreciate this testing!
>
> first_irq gets assigned to the info->virq_base making it 0.
>
> Later, in the __irq_domain_instantiate() we use the info->virq_base as a 
> condition for
> 	if (info->virq_base > 0)
>                  irq_domain_associate_many()
> which was previously unconditionally called in the irq_domain_add_legacy().

Thanks for troubleshooting!

For those who want an easy reproducer on QEMU (9.0.2):

make ARCH=mips CROSS_COMPILE=mips64-linux- 64r6el_defconfig
make ARCH=mips CROSS_COMPILE=mips64-linux- -j8
qemu-system-mips64el -M boston -cpu I6500 -kernel ./vmlinux -append "console=ttyS0,115200" -nographic

Thanks

>
>> Do you have any idea on how should we fix it?
> Maybe we could add a flag for domain association similar to the "bool 
> cond_alloc_descs", but maybe Thomas has some better ideas...?
>
>
> Yours,
> 	-- Matti
> -- 
> Matti Vaittinen
> Linux kernel developer at ROHM Semiconductors
> Oulu Finland
>
> ~~ When things go utterly wrong vim users can always type :help! ~~

-- 
- Jiaxun