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To: "Liam R. Howlett" , jeffxu@chromium.org, akpm@linux-foundation.org, willy@infradead.org, torvalds@linux-foundation.org, pedro.falcato@gmail.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org, jeffxu@google.com, lorenzo.stoakes@oracle.com, mpe@ellerman.id.au, oliver.sang@intel.com, vbabka@suse.cz, keescook@chromium.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 299254001B X-Stat-Signature: otbuo4zsw9gcbskcjcabw9m6imkjk88w X-Rspam-User: X-HE-Tag: 1723654641-601040 X-HE-Meta: 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 8iMD6Uip 3tGRh0DPhoNGoA4tiQ1USCyW/Ff42nT+PPNJL+RP0E87vQ0+roQ4NBNdHmnR33+s6vsYjO17tCDel4gtDrFOdGKt8ynILITyfGkYoQwPA+GWoww8KS5/dbT5LBAwUct0gVYPbIV0wO15sYesEMVeriS5uo5QorBjjjQRqdk2gNvZxOoOT+tl+lJqudjdsGem1egM0SwOEI9a6aoEYhl35hlyk/FpWqS3Ruz7fa5ktmrSLzv+1BCJers7TaCQyWiY3hLBAcv9NNB4fBWIK7mDWo2+sHJu84MhXUnpYg3+r03gXLcVCOk5rrIpHR4rKybUG1ZzevAaMPxO4gd8= 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 Wed, Aug 14, 2024 at 7:40=E2=80=AFAM Liam R. Howlett wrote: > > * jeffxu@chromium.org [240814 03:14]: > > From: Jeff Xu > > > > mremap doesn't allow relocate, expand, shrink across VMA boundaries, > > refactor the code to check src address range before doing anything on > > the destination, i.e. destination won't be unmapped, if src address > > failed the boundaries check. > > > > This also allows us to remove can_modify_mm from mremap.c, since > > the src address must be single VMA, can_modify_vma is used. > > I don't think sending out a separate patch to address the same thing as > the patch you said you were testing [1] is the correct approach. You > had already sent suggestions on mremap changes - why send this patch set > instead of making another suggestion? > As indicated in the cover letter, this patch aims to improve mremap performance while preserving existing mseal's semantics. And this patch can go in-dependantly regardless of in-loop out-loop discussion. [1] link in your email is broken, but I assume you meant Pedro's V1/V2 of in-loop change. In-loop change has a semantic/regression risk to mseal, and will take longer time to review/test/prove and bake. We can leave in-loop discussion in Pedro's thread, I hope the V3 of Pedro's patch adds more testing coverage and addresses existing comments in V2. Thanks -Jeff -Jeff