From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792500241; b=KFPTEWDXRd+8vp+xOIQUN9FJ3H8ZEbPBdIRu+xY8DYUfTc/p9Nyz++oQVMgwVnSH/Z1N 3jaGkznRFHk95byoaCkTozGaLS1wFGuaokAq8t2Jv0J6byDIRidJD757nfqA28h1OnaDs k6svfkkNXRIFZFbsa6qhtDWCRkkKqgvgKYmQy6qCTW53HVhsOwrBbaxbLvS5mxiAmWt3d SoTRZwY47np+TcrEjhSJ+bQeJ6G85NOXsOQMzuejELsbZh8guB42+DRhBrbb4rFrUbe82 0rQHNtTmxzXNajkVEjpwOP7hyVfJTUtHcSfozxAjqp7s9YOB0Of04C+fp5kWSyr4EKA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792500241; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=70044XyRM7M9zlZ1E3/O3HI1xtBAY4tCs57x88K8Ao8=; b=D/Nkdunn7GjfRhZCr0Q8Pdl1qCwGmTjRjqwfdC9vFMooD2X0nxJK1FZ4nFKFD9eugEX7 btNBBHn0AqW8SrTEPtE1N1i1kkSUFgRPxNr2Z0MlY0spoNHEWFJXzK0AJ/gz2hRgw/20F +lfnhzD9iYOWSUQstbwoAVTfFlrcsLmuYh172jjdxf4R7DR7UFqoKC9j8FlNa3u9/w+2S F5C3T6shofJzSTu4NtA26WlHIjc1Ece4JPgFLs8R5eVRvkwhLEp6AAl9z18GebhTgzt9M 6d731712jbr4Jb+n41h3axszrKvfdBi+7C2bdSF6A5NFhffFFFpziezE31UbJXFc3hg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=knUlUaYR; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DCCE6606A324 for ; Tue, 20 Oct 2026 12:44:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=knUlUaYR Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9351C1F000C4; Tue, 20 Oct 2026 12:44:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792500240; bh=70044XyRM7M9zlZ1E3/O3HI1xtBAY4tCs57x88K8Ao8=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=knUlUaYRbk5jjOfUatVr7/VWiwJXvSp7iTCe5FQm69nCEHjeI7ugUcyQoWRpjtv6F RlWf1qsH/luhRp6gwkE4eeiCrMBGbe6D08FEm5BOMW5US1icYZkVbxU0Rw/NMujtzW 01nVNEo4I+m+qYanxTprAQgNMD2+xXdekC3HE8rvkwLZSymyqGXvugOc3AlEDEyKEX mXRb90t+ROVNaXmugPuKroUco6Hv5Slu/mbmrOtWbOtBSFqIBOw1/lRKQWGXnSVgap gDgysUxvTiJooEpBlakxGVarPJPCBm4OeIDK70CLcL3tcPLiUXEXJGUwmbulVGaGqy tITt+UnHTbPWw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 1/3] PCI: Match the hierarchy's MPS to a device's MPSS as necessary Reply-To: sashiko-reviews@lists.linux.dev To: "Niklas Cassel" Cc: linux-pci@vger.kernel.org In-Reply-To: <20261020122854.1500883-6-cassel@kernel.org> References: <20261020122854.1500883-5-cassel@kernel.org> <20261020122854.1500883-6-cassel@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 20 Oct 2026 12:44:00 +0000 X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Hans Zhang <18255117159@163.com> >=20 > pci_configure_mps() enumerates top-down and programs each device's Maximum > Payload Size (MPS) to match its upstream bridge. When a device's MPS > Supported (MPSS) is too small to match, commit 9f0e89359775 ("PCI: Match > Root Port's MPS to endpoint's MPSS as necessary") reduces the upstream > bridge instead, but only when that bridge is a Root Port. >=20 > That covers an endpoint directly below a Root Port and nothing else. With > a Switch in between, the Switch ports have already inherited the Root > Port's larger MPS, the reduction is skipped because the upstream bridge is > a Switch Downstream Port, and pcie_set_mps() then fails with -EINVAL for > the endpoint. The endpoint is left below a port programmed for a larger > MPS, so any larger TLP it receives is treated as Malformed. >=20 > [ ... ] >=20 > Fixes: 9f0e89359775 ("PCI: Match Root Port's MPS to endpoint's MPSS as ne= cessary") > Signed-off-by: Hans Zhang <18255117159@163.com> > Co-developed-by: Niklas Cassel > Signed-off-by: Niklas Cassel Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261020122854.1500= 883-5-cassel@kernel.org?part=3D1