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Date:   Mon, 03 Jul 2023 11:11:27 -0700 (PDT)
Subject:     Re: [mm] 408579cd62: WARNING:suspicious_RCU_usage
In-Reply-To: <CAHk-=wijh9Gi14SRe0riD8Y9EdPpo3MNU_XDu8vpjY6xWdNhpQ@mail.gmail.com>
CC:     Marc Zyngier <maz@kernel.org>, Conor Dooley <conor@kernel.org>,
        apatel@ventanamicro.com, oliver.sang@intel.com,
        Liam.Howlett@oracle.com, linux-kernel@vger.kernel.org,
        lkp@lists.01.org, lkp@intel.com
From:   Palmer Dabbelt <palmer@rivosinc.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Message-ID: <mhng-ce7af44f-732e-4a48-adb4-62deb17b3eb9@palmer-ri-x1c9>
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On Mon, 03 Jul 2023 10:46:55 PDT (-0700), Linus Torvalds wrote:
> On Mon, 3 Jul 2023 at 10:34, Marc Zyngier <maz@kernel.org> wrote:
>>
>> Comparing with what we do on arm64, a less radical change would be to
>> move the IPI init after notify_cpu_starting(), which explicitly
>> enables RCU usage.
>
> Ack, that looks right to me.

I don't see anything wrong with it and it's passing my tests, but we've 
got a handful of ways to boot so it's all a bit messy and I might be 
messing something.

I'm still catching up a bit as I took both days off this weekend.  
Hopefully just an oversight in a bigger rafactoring, but I'll give it 
another look.

Marc: are you going to send that as a patch?