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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-rt-devel@lists.linux.dev Subject: Re: [PATCH 2/2] irqchip/gic-v3-its: Use GFP_ATOMIC_RT gfp flag in allocate_vpe_l1_table() In-Reply-To: <20260520204628.933654-2-longman@redhat.com> References: <20260520204628.933654-1-longman@redhat.com> <20260520204628.933654-2-longman@redhat.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: longman@redhat.com, tglx@linutronix.de, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-rt-devel@lists.linux.dev X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-Stat-Signature: m318pt8r5tn5kzaq9m8dssnyy8t1jhub X-Rspamd-Queue-Id: 8C9848000D X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1779437859-194947 X-HE-Meta: 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 CH9xkY6k +OeAldt9PLjxIvZi4D2/Xxcgz0pxGLxeP5zBlOn1Wy0ISgGOPZXk9Q7nbVgnAnG89GG06sF3OI3XpG9PCKxgRbeoOzyWBJclv3c2FN51fwfrms9AvlAEkbTcC3yajJOY8rU11onwM3XdOr1fzZ8Rxv1+lW2KaPq4sCWUMLoTPx2ovcXjCTT7ExLR1vtVD66eqc+qw1QrWaRmjXacwKN97+3hC1Fi/WzKE0meElodq4KkkXW9CaTZCUwJy8MimigefvN2oo9mitYfVhgww3GvnSW/TUgxMthPVksPi Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 20 May 2026 21:46:28 +0100, Waiman Long wrote: > > A longer term solution is to defer the allocation to a later stage of the > hotplug pipeline where interrupt isn't disabled. And that's what needs doing. Not papering over this in a bizarre way. I proposed a potential solution a few months back, but didn't get a chance to work on it. If you have the bandwidth, that's the way to go. But papering over this issue this way seems like a bad case of short term and unsustainable hack. Thanks, M. -- Without deviation from the norm, progress is not possible.