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Shutemov" Cc: Matthew Wilcox , Borislav Petkov , Andy Lutomirski , Dave Hansen , Sean Christopherson , Andrew Morton , Joerg Roedel , Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Dario Faggioli , Mike Rapoport , David Hildenbrand , Mel Gorman , marcelo.cerri@canonical.com, tim.gardner@canonical.com, philip.cox@canonical.com, aarcange@redhat.com, peterx@redhat.com, x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, stable@kernel.org, Nikolay Borisov Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 9933180003 X-Rspam-User: X-Stat-Signature: cqrt3839nj8psszbpp7z3z97eaiqd7kx X-Rspamd-Server: rspam01 X-HE-Tag: 1697528549-166307 X-HE-Meta: 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 OCTj7kkD o+zM0NrhWEZatHE8Tvxu/jj1tfpXGu2HTaVp1cVr+WOHwuoc9flOHZLGjq9yStBhUT610g4ATzt8i36wNwlpPSe2fvPXHDHcc5IcBSY6hS0npF6nlInkBq4AQ/wR/yhcfVtkbeQlXNCUfzsz8KOkcSCXhSf9HELKJNilTUhB0zDfhfuLdih4BLMkuspz8AEaw7rkuwpuwbnB9cbH0qRPqJOXvS9+fiJHigD+cj9sUGEtn5M0= 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: On Mon, 16 Oct 2023 at 23:39, Kirill A. Shutemov wrote: > > On Mon, Oct 16, 2023 at 06:55:41PM +0100, Matthew Wilcox wrote: > > On Mon, Oct 16, 2023 at 07:31:22PM +0300, Kirill A. Shutemov wrote: > > > v2: > > > - Fix deadlock (Vlastimil); > > > - Fix comments (Vlastimil); > > > - s/cond_resched()/cpu_relax()/ -- cond_resched() cannot be called > > > from atomic context; > > > > Isn't there an implicit cpu_relax() while we're spinning? Does this > > really accomplish anything? > > You are right. It is useless. I will drop it in v3. > I can drop that bit when applying the patch. One question I have is whether the sequence spin_lock_irqsave(&unaccepted_memory_lock, flags); ... spin_unlock(&unaccepted_memory_lock); arch_accept_memory(phys_start, phys_end); spin_lock(&unaccepted_memory_lock); ... spin_unlock_irqrestore(&unaccepted_memory_lock, flags); is considered sound and is supported by all architectures?