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From:   Michael Ellerman <patch-notifications@ellerman.id.au>
To:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Michael Ellerman <mpe@ellerman.id.au>
Cc:     linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
In-Reply-To: <bbb13848ff0100a76ee9ea95118058c30ae95f2c.1643613343.git.christophe.leroy@csgroup.eu>
References: <bbb13848ff0100a76ee9ea95118058c30ae95f2c.1643613343.git.christophe.leroy@csgroup.eu>
Subject: Re: [PATCH] powerpc/603: Clear C bit when PTE is read only
Message-Id: <164490280429.270256.7360085115220568003.b4-ty@ellerman.id.au>
Date:   Tue, 15 Feb 2022 16:26:44 +1100
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On Mon, 31 Jan 2022 07:17:57 +0000, Christophe Leroy wrote:
> On book3s/32 MMU, PP bits don't offer kernel RO protection,
> kernel pages are always RW.
> 
> However, on the 603 a page fault is always generated when the
> C bit (change bit = dirty bit) is not set.
> 
> Enforce kernel RO protection by clearing C bit in TLB miss
> handler when the page doesn't have _PAGE_RW flag.
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc/603: Clear C bit when PTE is read only
      https://git.kernel.org/powerpc/c/4634bf4455fe26f07dabf97c3585c9ccb86353c4

cheers