From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5066B2DA77F for ; Fri, 3 Oct 2025 18:25:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759515960; cv=none; b=WspSPLOybB10Ym7kQ0nz3WLL0gw4LwjLCtmV6vlaZVzE5z5HVuHNFu4WG8AGWtLfxPLOP1Ia+4nIBv2dG6d2mmS2KaeGPk8bQQ6N6RUJbcWgouldajQmFsqYjsIzdQyj+GrzhHCIONMl6qU/gpqRVRFlUGRkDBX3QkquAyJMgpY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759515960; c=relaxed/simple; bh=LActVDNHHJ01+cVP7NdYblEaRaHfOE6w3rkfKjPwdu0=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=Syn4KPKPHeV6CoAmlT7JRwdC2MWCHMLZ6Wk5ss5P3F5mAc+g2QZLgmzHJFce+rEUJi8APUhznJ0Pre3jdgd/fn+NujV45OwUgF+Pz6KbfI3MxG0vhrTVvG729RCegAXFfDWQbOG/fdUJEnFb5Mht8tSy5+P52cpMt+CYoKiqgE8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=i37GG8P2; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="i37GG8P2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1759515957; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LActVDNHHJ01+cVP7NdYblEaRaHfOE6w3rkfKjPwdu0=; b=i37GG8P2YTAVSmZ+cj1CiEPOtjhTn52e1RvFqS35ZUfUtbGHRBWPLaudRcjgvCEpY0Yccw cofY3vCqwmpQxU039bkZXu7g2a3BiJfkEZagZFvK0mdDbpp6XlsLvmWGlMGOePKpV3dyRz SwhKmIZ4hbVCjRGcQ/bfQ0QIe6AJ6zE= Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-214--60yLzFqME6rlllg9feWcA-1; Fri, 03 Oct 2025 14:25:56 -0400 X-MC-Unique: -60yLzFqME6rlllg9feWcA-1 X-Mimecast-MFC-AGG-ID: -60yLzFqME6rlllg9feWcA_1759515955 Received: by mail-qt1-f198.google.com with SMTP id d75a77b69052e-4dfe8dafd18so106687171cf.0 for ; Fri, 03 Oct 2025 11:25:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1759515955; x=1760120755; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=LActVDNHHJ01+cVP7NdYblEaRaHfOE6w3rkfKjPwdu0=; b=l9TVUWe3VHDWJwBQvWz2kqajCw5PM5KBgBxzroKeDLPDIkcKNZ+t9uLxX1fGtlXE9q oa9OrYQy0+O/kZd2OjKDKGhi4LJOK7hK63nIxzkWDE7BgEt7GuOZyqu95ZfdB2P97Xo/ E2y1aqb4soueTIQMfqfcKTpV9421A4gS9gZhA/qAf0SBiugU5KOAn3/lsr+JJWEoXuls Vf3E+YWYhNGmp6BwVtnZnYNpNNZTYqTAW/0bijz3d8xj5dYnTibbxuMcCN7LN0iNDmd4 fRqFhvI2d4oFmDNBdfbIrZVNiJGYBNPxBlnnUXn+bBwmDJv+Z3sLMjOKyNsyQVPNzOzJ DuSg== X-Forwarded-Encrypted: i=1; AJvYcCXBhYhQnKN+AxHFw++mo7g0k79wR+ve93WQXPJCf5Q4tE3PMOqDp1NAfDo7NbC6JlPI1FYLdx46L5U=@vger.kernel.org X-Gm-Message-State: AOJu0YzBBQK46SyHK3J0v5W8wR/beQ7Hr+dbPYvLO1RoT6xnQR2d9qr7 Y0cwyRu9OyozI/7e22y3x0CiyGhRfmfTAXf7/r3el3XqlqLlN9MP0zqvW9jRiVtbnN5wyI9caI+ /z/0/M11q/orGNhuQe5EirAWRlMBFeDwxSrRew2ywe4cWfg/kO7L5FjSIfzUIsQ== X-Gm-Gg: ASbGncsIqeg2oY5q1Jxnlnu0ctqgLtaGeyNW4Sd2ZD4TRq+pP5wEPA7oe5krQKBA+0v ICr1Kw/7vS3b3DseTlv61ymEzKX+5PbjyJFvG4xrPbOIYEgXatI/HcAOpWC7WFOimy+VoI/IvhF MBDkbq6JDWopl9EBHQmw1KVGNGOTjlDieCKWJPLHELuF3X1vx81WFlVbDhDnXrxrpoW7lsXGaJY ae+rHlpKo+zldv2j1TF/Ug1EqhRq47GqBYEywGI4AYkEyh/7ErJAtLvhWKksnk3vXRt7JVnJWLL bKUQbUsk7JUyWjGA6YlXFgHDnRMp/6fwEqedOxABIwW6PkRnCJO8A5T2bcqKLCirh7a5/0SGbw= = X-Received: by 2002:a05:622a:420b:b0:4de:5adb:20df with SMTP id d75a77b69052e-4e576b49fc9mr51800421cf.75.1759515955468; 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> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-1.fc42) Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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