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[109.81.23.83]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48150bf5f0esm4963432f8f.4.2026.08.12.01.14.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Aug 2026 01:14:33 -0700 (PDT) Date: Wed, 12 Aug 2026 10:14:32 +0200 From: Michal Hocko To: David Woodhouse Cc: Steven Rostedt , Jason Gunthorpe , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Sebastian Andrzej Siewior , Clark Williams , Simona Vetter , =?iso-8859-1?B?Suly9G1l?= Glisse , Christian =?iso-8859-1?Q?K=F6nig?= , "Paul E. McKenney" , Sean Christopherson , Paolo Bonzini , linux-mm@kvack.org, kvm@vger.kernel.org, linux-rt-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/mmu_notifier: Remove non_block_start/end() from notifier invocation Message-ID: References: <20260811135537.GC544626@ziepe.ca> <1d669aca4ffee797b9c29215382444a5b23624b3.camel@infradead.org> <20260811142730.GG544626@ziepe.ca> <20260811104229.72fdd928@gandalf.local.home> <37b83b429b9f14ea6ad4ca1c13cc8e565ec09033.camel@infradead.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <37b83b429b9f14ea6ad4ca1c13cc8e565ec09033.camel@infradead.org> On Tue 11-08-26 16:24:48, David Woodhouse wrote: [...] > I had a second reason for disabling the overzealous check too: to allow > SRCU grace periods within the notifier callbacks. Is there a way that srcu barrier could cause an indirect dependency on memory allocation? In other words what might block the scru to complete? -- Michal Hocko SUSE Labs