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From:   Michael Ellerman <patch-notifications@ellerman.id.au>
To:     Michael Ellerman <mpe@ellerman.id.au>,
        Paul Mackerras <paulus@samba.org>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc:     Finn Thain <fthain@linux-m68k.org>,
        Stan Johnson <userm57@yahoo.com>, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org
In-Reply-To: <2e3acfe63d289c6fba366e16973c9ab8369e8b75.1631803922.git.christophe.leroy@csgroup.eu>
References: <2e3acfe63d289c6fba366e16973c9ab8369e8b75.1631803922.git.christophe.leroy@csgroup.eu>
Subject: Re: [PATCH v2] powerpc: warn on emulation of dcbz instruction in kernel mode
Message-Id: <163584790970.1845480.2701645430318676678.b4-ty@ellerman.id.au>
Date:   Tue, 02 Nov 2021 21:11:49 +1100
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On Thu, 16 Sep 2021 16:52:09 +0200, Christophe Leroy wrote:
> dcbz instruction shouldn't be used on non-cached memory. Using
> it on non-cached memory can result in alignment exception and
> implies a heavy handling.
> 
> Instead of silentely emulating the instruction and resulting in high
> performance degradation, warn whenever an alignment exception is
> taken in kernel mode due to dcbz, so that the user is made aware that
> dcbz instruction has been used unexpectedly by the kernel.
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc: warn on emulation of dcbz instruction in kernel mode
      https://git.kernel.org/powerpc/c/cbe654c779616807e1e6823c3bdbfe07a10562b8

cheers