From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) (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 5A3E335E956; Fri, 18 Sep 2026 20:00:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=204.191.154.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789761601; cv=none; b=gxmnZerjEWLcNSrBDAEnlRm8aikLN4LoMLtTqXF9+JVLni7x+H0xgNZuGmnHW7uzcvNkAhWon2LGYPA1btg8Z2er+9GzqP7G3Tsjf5fiE+Alv4idm8l+OaJFBIYy7My3d/ep3TT+OqQENKnWQkVZLqcBuWeTaUM8m2qS01WENOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789761601; c=relaxed/simple; bh=ujkhGy2FSYAIasmOkN8vs+uHhKJMbQlyvbnsVAWbj1o=; h=Message-ID:Date:MIME-Version:To:Cc:References:From:In-Reply-To: Content-Type:Subject; b=IKzrhETNZm4Id2TBQ2+vdXFmAhy8b4lD3Ijd2as9QzU+nElmDRICochwDeUUPxTomKA5Vp2OuUJhPn53cRZayk1b8NR0mMZn76nmPJAxC+iElqQ2CFixUjUxQrOLcOoW59UavlLsEKQVRmUule42wpuRs49zkr98pfHdnZKQEgw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com; spf=pass smtp.mailfrom=deltatee.com; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b=W/ONbTcH; arc=none smtp.client-ip=204.191.154.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=deltatee.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b="W/ONbTcH" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:In-Reply-To:From:References:Cc:To: MIME-Version:Date:Message-ID:content-disposition; bh=cmiry3JcpazZ6l/PDBYrf3Gg/OWOS79zaTVf2b02IB0=; b=W/ONbTcHvbbIcERFDBy5V9+fz8 ClXKlqhfI9/+PEX5UPZD/o9kNZB2xeLc6zsCCTmVEebXhBjHQB1VHAH3gZOcPOirQCS5xTtaH0f5y s0JCpmFhn7hlwfUnwEhUXZMND0d06IpSnuXzm8j86ZILMwQr8gCPbjPiwyNNd/0T4UK7TSQzEcPNC 5aqkcHGEO3iirTALpNPzRsqeyqDK7uUa2nahHS2hhtAH2q05KmkruKKkOSr1EwNbW/d6ezacx2EXb kuJwha3ZRhs0SHbPVT9LjGFOUI6TCSn71LmSJBR0L8gAurJAb3h9zxd1NU58TeZwTWpyag9nqPIUW MSa9+CMQ==; Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.98.2) (envelope-from ) id 1x7ekV-0000000Cs4I-1zVG; Fri, 18 Sep 2026 13:59:56 -0600 Message-ID: <1384e37c-d4d4-41d7-8d74-c4e60f52c9d7@deltatee.com> Date: Fri, 18 Sep 2026 13:59:54 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Leon Romanovsky , Bjorn Helgaas , Chaitanya Kulkarni , Greg Kroah-Hartman , Jens Axboe , Alex Williamson , Ankit Agrawal , Jason Gunthorpe , Jonathan Corbet , Shuah Khan , "Joerg Roedel (AMD)" , Will Deacon , Robin Murphy , Randy Dunlap , Sumit Semwal , =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, iommu@lists.linux.dev, Tushar Dave , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-rdma@vger.kernel.org, kvm@vger.kernel.org References: <20260914-fix-p2p-acs-v4-0-v6-0-5ef07ec9ef06@nvidia.com> <20260914-fix-p2p-acs-v4-0-v6-4-5ef07ec9ef06@nvidia.com> Content-Language: en-CA From: Logan Gunthorpe In-Reply-To: <20260914-fix-p2p-acs-v4-0-v6-4-5ef07ec9ef06@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: leon@kernel.org, bhelgaas@google.com, kch@nvidia.com, gregkh@linuxfoundation.org, axboe@kernel.dk, alex@shazbot.org, ankita@nvidia.com, jgg@ziepe.ca, corbet@lwn.net, skhan@linuxfoundation.org, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, rdunlap@infradead.org, sumit.semwal@linaro.org, christian.koenig@amd.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, iommu@lists.linux.dev, tdave@nvidia.com, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-rdma@vger.kernel.org, kvm@vger.kernel.org X-SA-Exim-Mail-From: logang@deltatee.com X-Spam-Level: Subject: Re: [PATCH v6 04/18] PCI: Reject unreadable ACS controls in isolation checks X-SA-Exim-Version: 4.2.1 (built Sun, 23 Feb 2025 07:57:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) On 2026-09-14 05:22, Leon Romanovsky wrote: > From: Leon Romanovsky > > pci_acs_flags_enabled() and the Intel SPT PCH quirk use ACS registers > without checking config-space read errors. A failed read may leave control > state indeterminate yet allow the device to satisfy requested isolation > controls. > > Return false when either ACS capability or control state cannot be read. > An unknown state cannot prove isolation. > > Signed-off-by: Leon Romanovsky Looks good to me. Reviewed-by: Logan Gunthorpe