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Fri, 03 Oct 2025 11:25:55 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHl6MbKs3Xb6exRfHKs8R/8W88faZKEv/f6HSCYFxtPk4/rUynv2mK5zOAipf0zbQgK3MTWtQ== X-Received: by 2002:a05:622a:420b:b0:4de:5adb:20df with SMTP id d75a77b69052e-4e576b49fc9mr51799931cf.75.1759515954967; Fri, 03 Oct 2025 11:25:54 -0700 (PDT) Received: from crwood-thinkpadp16vgen1.minnmso.csb ([50.145.183.242]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-878bdf52afcsm44134596d6.46.2025.10.03.11.25.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Oct 2025 11:25:54 -0700 (PDT) Message-ID: <1b3684b424af051b5cb1fbce9ab65fc5cdf2b1a1.camel@redhat.com> Subject: Re: [PATCH] genirq/manage: Reduce priority of forced secondary IRQ handler From: Crystal Wood To: Lukas Wunner , Thomas Gleixner Cc: Sebastian Andrzej Siewior , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Clark Williams , Steven Rostedt , Dietmar Eggemann , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org, Attila Fazekas , linux-pci@vger.kernel.org, linux-rt-devel@lists.linux.dev, Bjorn Helgaas , Mahesh J Salgaonkar , Oliver OHalloran Date: Fri, 03 Oct 2025 13:25:53 -0500 In-Reply-To: References: <83f58870043e2ae64f19b3a2169b5c3cf3f95130.1757346718.git.lukas@wunner.de> <87348g95yd.ffs@tglx> User-Agent: Evolution 3.56.2 (3.56.2-1.fc42) Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: zFAph7Rh5bGwWiqZSQsmp6773fVrNYb8SHp1EsLM8nQ_1759515955 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sun, 2025-09-21 at 15:12 +0200, Lukas Wunner wrote: > On Sat, Sep 20, 2025 at 11:20:26PM +0200, Thomas Gleixner wrote: > > I obviously understand that the proposed change squashs the whole class > > of similar (not yet detected) issues, but that made me look at that > > particular instance nevertheless. > >=20 > > All aer_irq() does is reading two PCI config words, writing one and the= n > > sticking 64bytes into a KFIFO. All of that is hard interrupt safe. So > > arguably this AER problem can be nicely solved by the below one-liner, > > no? >=20 > The one-liner (which sets IRQF_NO_THREAD) was what Crystal originally > proposed: >=20 > https://lore.kernel.org/r/20250902224441.368483-1-crwood@redhat.com/ So, is the plan to apply the original patch then? Thanks, Crystal