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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) MIME-Version: 1.0 X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 656C72000D X-Rspam-User: X-Stat-Signature: tubi7hksxdciyeqofjgtujei3rorwxt6 X-HE-Tag: 1735661757-51719 X-HE-Meta: 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 PMqxGM51 zVRzt4YqOMAnHCHnXXeu5cBefEaQOFqp3bRUVijz6ciIYrQjow8P2EzbuhLNHbqyg8NZLC8UHfnyMFAvXp2HHeF8Jiho+OrK8qenqKKHvxExF2rW2H5zMAHEFrxT11n4flB4mBWVv4/THeNQHhOs0cA6vavUJ4Cxe/BWSgs9PuKYZeqfU+LhG8BFX1imtkTNveg0UqYx/poRdbAUf15isBSCaY7ZQ49CMzeCNBxSdZkZwESEQLOQFxBqjox3Ctn4vHGmTtY9qyDLI8vecfneaFW0iWNXMm5x7Sn+YgVGxi9nn0IyJzAbxwnvgHLzRPgDR3pb43kGtg9xs7X7yWOjq/+1CO/2nnqENai15Nh/YMJ2OJ+ce+Ugzosx9C2BY0xyxCc+T X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 2024-12-30 at 19:41 +0100, Borislav Petkov wrote: > On Mon, Dec 30, 2024 at 12:53:02PM -0500, Rik van Riel wrote: > > Currently x86 uses CONFIG_MMU_GATHER_TABLE_FREE when using > > paravirt, and not when running on bare metal. > >=20 > > There is no real good reason to do things differently for > > each setup. Make them all the same. > >=20 > > After this change, the synchronization between get_user_pages_fast > > and page table freeing is handled by RCU, which prevents page > > tables > > from being reused for other data while get_user_pages_fast is > > walking > > them. >=20 > I'd rather like to read here why this is not a problem anymore and > why >=20 > =C2=A0 48a8b97cfd80 ("x86/mm: Only use tlb_remove_table() for paravirt") >=20 > is not relevant anymore. That would be a question for Peter :) >=20 > > This allows us to invalidate page tables while other CPUs have > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ^^ >=20 > Please use passive voice in your commit message: no "we" or "I", etc, > and describe your changes in imperative mood. Will do. Between your feedback, the suggestions from Qi and Nadav, and the kernel test robot flagging some build issues without CONFIG_CPU_SUP_AMD, there's enough to warrant a v4 :) --=20 All Rights Reversed.