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Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vxrSh-0000000Dl6K-15gd; Wed, 04 Mar 2026 19:00:47 +0000 Date: Wed, 4 Mar 2026 19:00:47 +0000 From: Matthew Wilcox To: "Lorenzo Stoakes (Oracle)" Cc: Suren Baghdasaryan , Lorenzo Stoakes , akpm@linux-foundation.org, david@kernel.org, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, gourry@gourry.net, ying.huang@linux.alibaba.com, apopple@nvidia.com, baolin.wang@linux.alibaba.com, Liam.Howlett@oracle.com, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, vbabka@suse.cz, jannh@google.com, rppt@kernel.org, mhocko@suse.com, pfalcato@suse.de, kees@kernel.org, maddy@linux.ibm.com, npiggin@gmail.com, mpe@ellerman.id.au, chleroy@kernel.org, borntraeger@linux.ibm.com, frankja@linux.ibm.com, imbrenda@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, svens@linux.ibm.com, gerald.schaefer@linux.ibm.com, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, "Ritesh Harjani (IBM)" Subject: Re: [PATCH v3 2/3] mm: replace vma_start_write() with vma_start_write_killable() Message-ID: References: <20260226070609.3072570-1-surenb@google.com> <20260226070609.3072570-3-surenb@google.com> <74bffc7a-2b8c-40ae-ab02-cd0ced082e18@lucifer.local> <76aff8f9-1c08-449a-a034-f3b93440d1a8@lucifer.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <76aff8f9-1c08-449a-a034-f3b93440d1a8@lucifer.local> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: F2A994001A X-Stat-Signature: hk8ga5sgdr8r6gqxqs9eda5tquijtrg5 X-Rspam-User: X-HE-Tag: 1772650866-263198 X-HE-Meta: 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 izEiNFPl eleTHzFAcTXAYoUtQiW+rsojlNPLJA5bfZ4S6ItmXTw7U3BqbV7fdW/PYswJwDyu8NBHWq1GemgwguIB1Lby8Vl8rucqB1W0NSSFVWpvm5KSl+Usf2o2La8tqSVbSZZH77Ng6LwVZ8izWa15i9C1IGBRVrRm0PhjTpm/st50bzFNBhXKXL4CfF8YTfNoyWKOrH6zeq2R/z+u+ke8wUR+wfL1WDjWVRCAGkJxA71gGfHYz1q5cI6RMA7UT1nmvGg6gmHmVCB97qfJhjaefk0u5s2bZ0jMaT4EAn1w3i+XdXYnNtZYXzkWrb0QIX0w/Lq+anLokstC+N1kHKnmlQg9e9MbRWkLDEo7fkQg3gzkuadN9o2B+8Ydz+FfSSA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 04, 2026 at 04:53:27PM +0000, Lorenzo Stoakes (Oracle) wrote: > On Wed, Mar 04, 2026 at 03:24:05AM +0000, Matthew Wilcox wrote: > > We could literally return any error code -- it never makes it to > > userspace. I forget where it is, but if you follow the syscall > > return to user path, a dying task never makes it to running a single > > instruction. > > Thanks for that Matthew, that makes life easier then. > > We can probably replace some of the more horrid if (err == -EINTR) stuff with > fatal_signal_pending(current) to be clearer as a result. Umm. Be careful? fatal_signal_pending() may become true at a later point, so you may have acquired the lock _and_ fatal_signal_pending() can be true. I'd need to audit a patch to be sure that it's a reasonable replacement.