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Date:   Wed, 7 Sep 2022 21:35:49 -0300
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Subject: Re: [PATCH V3] firmware: google: Test spinlock on panic path to avoid
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To:     Evan Green <evgreen@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Greg KH <gregkh@linuxfoundation.org>
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        kernel@gpiccoli.net, Ard Biesheuvel <ardb@kernel.org>,
        David Gow <davidgow@google.com>,
        Julius Werner <jwerner@chromium.org>
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From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 06/09/2022 14:09, Evan Green wrote:
> [...]
> 
> I basically came to the same conclusion as Andrew. It seems like this
> patch does fix a problem, which is a panic coming in on another CPU
> and NMIing on top of a CPU doing a normal operation holding this lock.
> The problem seems pretty theoretical, but I suppose I don't have
> numbers one way or another since any attempt to gather numbers would
> be reliant on this very mechanism. My Reviewed-by tag is already on
> there.
> -Evan

Thanks for the feedback Evan and Andrew.

So if Greg (or anybody else) doesn't oppose, I'll send a V4 with the
commit message/comment suggestions.

Cheers,


Guilherme