From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 72DDE46D558 for ; Mon, 5 Oct 2026 12:08:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791202126; cv=none; b=VWdYCoTaaaSPIMmDMjLAFHxn41P2R+iMZSfRG7BwsXLiUZYAgJbiHKRrEorYCTTH07QdIxkiBhsgd+NwzxoXsePklJ7ouL02WvboLRcYKh6eWvnMI5uZkvY6XTF/DMMFP1JBl3noSpOt34Sf3Zv2uKAtVANMyHuNjGp6se2vvVw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791202126; c=relaxed/simple; bh=ZrLk4xRj5C458a4QV32SAi6WRUJfb8u+GdQqkUtOPXw=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=VeQMyLvwaSkZGagwbrrCYBUw6YblhF0gW/I6hOYc5HL5rLkdbNkjauV0TOI9yN9uJHTbCD5JxWya+nX/e7dfDn5z9JgbmnWbmLh3Elk784lVPnGDRlIUB9hD4IGpTCba/BX80V23n+cX+8CGR1Q5ol3hwYxkZKRyAL1Fvi4rmLc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ltwxFqo/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ltwxFqo/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDC871F000FF; Mon, 5 Oct 2026 12:08:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791202125; bh=BgtVgL4StLMv8cKhI86zCDTEcztk7A5vJhq4Hv1SLNk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ltwxFqo/24YplKxgZ8n4lyVa4Sn7q94xCabOf+JlgAzcqXUlJqoGbQnEhJaKh7X4f beYpUqi+xqV9Xkp0+R2t4jMg2iN1CZitcRSg2kLV8qwtSMIEKsZdgdZSyqAq9nL8yR 3BW85tJXOvI5kwZIXUsDEoF9XQkBKHe5IHBxIUZyDpKD56qr6coXRh/V9m04n3exOH dE+xdFwM75Pxvg8CNvIHlpV7Fm6jg4pQ0pzFd6LWdVq5fzrUmC0Ri3UVMBITjjAgDS RwZgWB/hezNXV1XyHavlfKfCu4eXjgk4RqWatrnrwVeISO7L1gprjMQ0DsxxF5KuNE h043UBM00MSPw== From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 6/7] s390/pci: Set MSI_FLAG_NO_AFFINITY at IRQ init time Reply-To: sashiko-reviews@lists.linux.dev To: "Tobias Schumacher" Cc: "Heiko Carstens" , "Vasily Gorbik" , "Christian Borntraeger" , linux-s390@vger.kernel.org, "Alexander Gordeev" In-Reply-To: <20261005-s390_irq_domain_fixes-v2-6-d45b824874c0@linux.ibm.com> References: <20261005-s390_irq_domain_fixes-v2-0-d45b824874c0@linux.ibm.com> <20261005-s390_irq_domain_fixes-v2-6-d45b824874c0@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 05 Oct 2026 12:08:44 +0000 Message-Id: <20261005120844.CDC871F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > MSI_FLAG_NO_AFFINITY is added to zpci_msi_parent_ops.required_flags from > zpci_create_parent_msi_domain(), which runs for every new PCI bus, > including buses created at runtime from a hotplug availability event. >=20 > That is a non-atomic read-modify-write on a field which > msi_lib_init_dev_msi_info() reads without a common lock while setting up > MSI for a device on an already existing bus: >=20 > required_flags =3D pops->required_flags; >=20 > The stored value is always the same, so no caller observes a change, but > the race need not exist: irq_delivery is decided once in zpci_irq_init() > and never changes afterwards. >=20 > Set the flag there instead, before any parent domain exists. >=20 > Signed-off-by: Tobias Schumacher Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261005-s390_irq_d= omain_fixes-v2-0-d45b824874c0@linux.ibm.com?part=3D6