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Date:   Wed, 7 Sep 2022 14:34:27 +0100
From:   Will Deacon <will@kernel.org>
To:     Qi Zheng <zhengqi.arch@bytedance.com>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Arnd Bergmann <arnd@arndb.de>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Mark Rutland <mark.rutland@arm.com>
Subject: Re: [PATCH v3] arm64: run softirqs on the per-CPU IRQ stack
Message-ID: <20220907133426.GA30248@willie-the-truck>
References: <20220815124739.15948-1-zhengqi.arch@bytedance.com>
 <595c912a-1503-d420-f32f-297b824decae@bytedance.com>
 <430e3e5f-d446-6307-cba0-6f859bce560f@bytedance.com>
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On Wed, Sep 07, 2022 at 03:04:48PM +0800, Qi Zheng wrote:
> 
> 
> On 2022/8/26 12:16, Qi Zheng wrote:
> > 
> > 
> > On 2022/8/15 20:47, Qi Zheng 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>
> > > Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> > > Acked-by: Will Deacon <will@kernel.org>
> > > ---
> > > v2: https://lore.kernel.org/lkml/20220802065325.39740-1-zhengqi.arch@bytedance.com/
> > > v1: https://lore.kernel.org/lkml/20220708094950.41944-1-zhengqi.arch@bytedance.com/
> > > RFC: https://lore.kernel.org/lkml/20220707110511.52129-1-zhengqi.arch@bytedance.com/
> > > 
> > > Changelog in v2 -> v3:
> > > ? - rebase onto the v6.0-rc1
> 
> Hi Will,
> 
> Are we good to merge this patch? Or if there is anything else I need to
> do, please let me know. :)

I'm expecting Catalin to pick this one up for 6.1.

Will