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 1A482395DBF for ; Sun, 2 Aug 2026 15:50:51 +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=1785685853; cv=none; b=Yyf5u1ROSDXZKBfCDEqqxHYOBuZpCSkM+jNyYHEq56kNp8Y1Zx53oTLcDAmFs5DtMIrUOMLSK04bUa6DPzofOrchdBwyLwOFTiuHH82qAtP0T6ZyGq/P4OsTa61sR6HIY5YUw7+m+aXBz3MPpy4L0xRug1Vp4bvfzar/4eHKAQs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785685853; c=relaxed/simple; bh=jbtjG2iwrY4Vm48rvmDVMacAnTcueCosg99BtnDNTnI=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=C//o3HcEnuv7k2J//z7i9nuzAPhuEvZScKtJ/BURAVqXo+nfl1Eb00oYxPHVvJW/9/RUO5HKuDX2y7rcDZ+dxkdCGzOZj7mntirhTPn5SWJ0o6snXS2nuQrcjtswiCBq7OjRH9H2I7OQZw1gOlu0wJifGbjw/mtcGEwweYk1V5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FoivzLgh; 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="FoivzLgh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B07E01F000E9; Sun, 2 Aug 2026 15:50:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785685851; bh=jbtjG2iwrY4Vm48rvmDVMacAnTcueCosg99BtnDNTnI=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=FoivzLghMGDlhx6Yq9W6UT1jCdpaLK5vtPva8v/C1Y6qXMf5hW28u/EznVbd6ZEO9 dggKywSN2Z0lR/cmIj0vj+uLgsGoy+pWNzrhK6gzDkxKUwxv2Setmx9r9PxTcAp4dB iRH0v8bcAYXAm4OXVM+yFE6NZFTE2gVBy+y1UMVZwjRzTSgEn/qXWskxiPYTi4+rnA c78VydiHL5FeK9kLKhXUsVd4zvr4ia9a1RjjSzHKc31oINSVYUd/ZxD4QLObMO0bmP ELhG6rkHb9ZVZNhzJ0z3SdeC12t+gVoWdZC2L2701wbgVOVrhHHkJm9DYJUfG5GDun 0w8bcJpWbcrGA== From: sashiko-bot@kernel.org Subject: Re: [PATCH 06/13] PCI: Account for ACS egress control in isolation checks Reply-To: sashiko-reviews@lists.linux.dev To: "Leon Romanovsky" Cc: linux-pci@vger.kernel.org In-Reply-To: <20260802-fix-p2p-acs-v1-6-a7c5eb64fff6@nvidia.com> References: <20260802-fix-p2p-acs-v1-0-a7c5eb64fff6@nvidia.com> <20260802-fix-p2p-acs-v1-6-a7c5eb64fff6@nvidia.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sun, 02 Aug 2026 15:50:51 +0000 Message-Id: <20260802155051.B07E01F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > From: Leon Romanovsky >=20 > pci_acs_enabled() treats P2P Request Redirect as effective whenever its > control bit is set. PCIe r7.0, sec 6.12.3, table 6-11 lets an enabled > Egress Control Vector override it: a clear vector bit routes the request > directly. >=20 > IOMMU grouping uses this check to prove peer requests cannot bypass the > IOMMU, but cannot know every applicable vector bit, so Request Redirect > gives no such guarantee while Egress Control is enabled. >=20 > Report Request Redirect as ineffective there, merging the devices into > one IOMMU group, and report no isolation when the register cannot be > read. Apply the same rule to the Intel SPT PCH quirk. >=20 > Signed-off-by: Leon Romanovsky Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260802-fix-p2p-ac= s-v1-0-a7c5eb64fff6@nvidia.com?part=3D6