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McKenney" Cc: Sean Christopherson , David Woodhouse , Jason Gunthorpe , Michal Hocko , Steven Rostedt , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Clark Williams , Simona Vetter , Jerome Glisse , Christian Koenig , 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: <20260826073233.T-KtFXmj@linutronix.de> References: <333c4cdb-8f34-4e3f-a47f-961f47e089a0@paulmck-laptop> <11dcf5a87125451897982f728c1f65a5151987e4.camel@infradead.org> <69567965-48fd-48c5-abb6-0699d7f5bd16@paulmck-laptop> <124af87fb49c267eeb26b8b4d952b9b1a5b3fb68.camel@infradead.org> <9427a8e0-3ba6-4f31-a35d-54429bd7e071@paulmck-laptop> <3d0463b6099d4fcde9a025a2f9e231d75303b61c.camel@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: X-Stat-Signature: 7abxi3gkcp1kok8q7na5su4bce1p6dgb X-Rspamd-Queue-Id: 5B96280002 X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1787729562-3689 X-HE-Meta: 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 CHToO/7W KZEDBsFjuFZArNopRCmfcD3YVOkQLDg1W/Fs0vFzB8bmzVm011Zx99pHYX3Fsfig6bZMr4NnRt9PaIZ4JZFXOloe3pN5QXMC5s0+/UzKYcPSjfuPhkdUv/f2B6iuT1tTyOmCb8g3QjFIkMViKeqmqpcJKpkMLw9CdB4sjOEHD+UmL+D4cMK4rU+0s6cSc1WW1kblYtFgeCUUrCj15KLdmWKBrrRXdtwu+3KJ0w7ln5MJw750CZeq8YcEhww== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026-08-25 13:51:14 [-0700], Paul E. McKenney wrote: > Very good, preemption disabling it is! It is quite possible that the > PREEMPT_RT guys will need something else, but one thing at a time. This reminds me of classic RCU ;) It might work in this use case but I am afraid that other users might come along where it actually hurts. With PREEMPT LAZY the preemption within the read-section should hopefully be the exception. =E2=80=A6 > Thanx, Paul Sebastian