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Howlett" , Vlastimil Babka , Mike Rapoport , Michal Hocko , Matthew Wilcox , iommu@lists.linux.dev, security@kernel.org, x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20251014130437.1090448-1-baolu.lu@linux.intel.com> <20251014174339.c7b7d2cfb9f60d225e4fe5ec@linux-foundation.org> <6b187b20-6017-4f85-93ac-529d5df33aa2@linux.intel.com> Content-Language: en-US From: Baolu Lu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: C2BA2C0002 X-Rspamd-Server: rspam02 X-Stat-Signature: 8byosmqmobofh47geooah5k7ekczwhm7 X-HE-Tag: 1760665561-449956 X-HE-Meta: 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 J0DKqNq1 +g77few5MFKeAuo04dUsjgGZjzIomaA+ue3j5p9nF1f53Mbt5U6s/u1VeCoXVahwulsQO2+LI1lsiKqff0hQuZkO/7eC7HbqKrn92CzTnorjq/yefz2Bh/qN8qULdziJV9dIdhSlqXyJWSjzmGtiAk1jsWWuKftVo/9EkkLKafi90eLxrzPcXn/R0epbd5veCcpxjl+mAnm1nISZPIVBq2InBQ6lGzhr7RtlB 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 10/15/25 23:55, Dave Hansen wrote: >>> Only [7/7] has acc:stable, even though that patch is not at all >>> backportable.  Please give some thought and suggestions regarding >>> whether you think we should backport this into earlier kernels. >> Yes. We should backport this series to stable kernels. >> >>> If "yes" then the size and scope of the series looks problematic.  Is >>> it possible to put together something simple and expedient just to plug >>> the hole in older kernels? >> Squashing some patches is one way. But would it be workable to backport >> this series manually? Say, could we send a pull request to the stable >> mailing list after this series has landed? > I honestly think we should just disable SVA in old kernels at compile > time, or at least default it to be disabled at runtime. That's the > simplest thing. > > The other alternative is to have arch_vmap_pmd_supported() return false > when SVA is active, or maybe when it's supported on the platform. > > Either of those are 10-ish lines of code and easy to backport. Hi iommu folks, any insights on this? Thanks, baolu