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Peter Anvin" , Jacob Pan , Jason Gunthorpe , jpoimboe@kernel.org, Joerg Roedel , juri.lelli@redhat.com, Kent Overstreet , kinseyho@google.com, "Kirill A. Shutemov" , lstoakes@gmail.com, mgorman@suse.de, mic@digikod.net, michael.christie@oracle.com, Ingo Molnar , mjguzik@gmail.com, "Michael S. Tsirkin" , Nicholas Piggin , "Peter Zijlstra (Intel)" , Petr Mladek , Rick P Edgecombe , Steven Rostedt , Suren Baghdasaryan , Thomas Gleixner , Uladzislau Rezki , vincent.guittot@linaro.org, vschneid@redhat.com Content-Type: text/plain; charset="UTF-8" X-Rspam-User: X-Stat-Signature: 1mi39idddpgau43unmm4xowhk8as1tmo X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 61AAF40019 X-HE-Tag: 1710203058-938189 X-HE-Meta: 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 nmVz4rNi B7a0VkMOQFu86fUWQnm2QcDWDrgUSVs7KJ0YmaYPP04P7GEH0rLyJtHiaqQAlUCoRkLhKLQkmt28Gq7j8F+58eYFX2sASTGERv6AF 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: > > > > You can't block when scheduling, either. What if you can't refill the pool? > > Why can't we (I am not a scheduler guy)? IRQ's are not yet disabled, > what prevents us from blocking while the old process has not yet been > removed from the CPU? Answering my own question: single cpu machine, the thread is going away, but tries to refill the dynamic-pages, alloc_page() goes into slow path i.e (__alloc_pages_slowpath), where it performs cond_resched() while waiting for oom kills, and yet we cannot leave the CPU.