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From:   Michael Ellerman <patch-notifications@ellerman.id.au>
To:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Paul Mackerras <paulus@samba.org>,
        Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
In-Reply-To: <ce30364fb7ccda489272af4a1612b6aa147e1d23.1637227521.git.christophe.leroy@csgroup.eu>
References: <ce30364fb7ccda489272af4a1612b6aa147e1d23.1637227521.git.christophe.leroy@csgroup.eu>
Subject: Re: [PATCH] powerpc/32: Fix hardlockup on vmap stack overflow
Message-Id: <163783287691.1228083.396612201232244532.b4-ty@ellerman.id.au>
Date:   Thu, 25 Nov 2021 20:34:36 +1100
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On Thu, 18 Nov 2021 10:39:53 +0100, Christophe Leroy wrote:
> Since the commit c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not
> activate MMU before reading task struct") a vmap stack overflow
> results in a hard lockup. This is because emergency_ctx is still
> addressed with its virtual address allthough data MMU is not active
> anymore at that time.
> 
> Fix it by using a physical address instead.
> 
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/32: Fix hardlockup on vmap stack overflow
      https://git.kernel.org/powerpc/c/5bb60ea611db1e04814426ed4bd1c95d1487678e

cheers