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Message-ID: <6541e3d2-69cc-2970-c7db-fde4d64a2f09@bytedance.com>
Date:   Thu, 14 Jul 2022 19:50:38 +0800
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Subject: Re: [PATCH v1 1/2] arm64: run softirqs on the per-CPU IRQ stack
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To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20220708094950.41944-1-zhengqi.arch@bytedance.com>
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 <CAK8P3a2kgVikkKBZLa31XUopEFa9ykLS=qxiH=qiFD8HtUvw=A@mail.gmail.com>
From:   Qi Zheng <zhengqi.arch@bytedance.com>
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On 2022/7/14 19:32, Arnd Bergmann wrote:
> On Fri, Jul 8, 2022 at 11:49 AM Qi Zheng <zhengqi.arch@bytedance.com> wrote:
>>
>> Currently arm64 supports per-CPU IRQ stack, but softirqs
>> are still handled in the task context.
>>
>> Since any call to local_bh_enable() at any level in the task's
>> call stack may trigger a softirq processing run, which could
>> potentially cause a task stack overflow if the combined stack
>> footprints exceed the stack's size, let's run these softirqs
>> on the IRQ stack as well.
>>
>> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
> 
> This seems like a nice improvement, and this version addresses
> my concern I raised on the RFC version.
> 
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Thanks for your review. :)

-- 
Thanks,
Qi