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 9FC5843440B for ; Mon, 21 Sep 2026 11:13:53 +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=1789989235; cv=none; b=DJ142AAN/MD1djOuLr3gXMFRcX5N5QhSqsoEwnsPmViI2THO3Nl+j3yjKK0HMLpcw7wb5BYiXImY3tJdHsBJzWXbG/KuNnZWvoDL2r+956EBTUyCiUzkspkCqkHTYrBbeSEqLu/MjgIlWudK1G4mx862AIZIzkQSYveBtazdERM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789989235; c=relaxed/simple; bh=z0vu0kEnDB+8UBzPJgSwvFS7h1r+pMvYBif+BXXr4RI=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=T7KSnK51gDir7b1V7HNv6lo+LtPrOB50DGTB0WEvGqcXKRLz9U9o0vgqpoB40/soz3APFQPwc3iPzeZNE2kg2m/yhhlnviVzsKEtoTCSW0+y1+ry4FO5601BhmEreBiL5ObdzVMjbzgkfjvSgDiAIR+MAc+m27x/V7/iDsXThqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EcdDZ4dQ; 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="EcdDZ4dQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0848A1F000FF; Mon, 21 Sep 2026 11:13:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789989233; bh=LX4oYrS8lYFIbr7adLnZHEASATvsdGjZX/xQPNzeBG0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=EcdDZ4dQ9Vmq0htPbfIzWwNzYQa+bcT+2V2mYr9/uYSUGUOzPz0NXtVQmAazM8al3 rHNu2bv83o99OWm2PbQMDG8nPOjqzzzYFiyG1MSFapy2IYxOFxwUmkMtDmfu5Q2SR8 UgkiPePA1Q6Own/RetcZf9dHui2JrUQYml8CpLpP7yDlvbETV8p8Z0NTenAz0lj3cQ yUtrtIl9QYhm9vA8nxRrKKieelNnS0p3/sN9elO4TmGbkxg25Ay0Nr5gqP/4H5IHpo rXGwxv+YEPn3WfOPMRiVdD5JGYydauv0rv/uLQHJ4ZUmy30YsOwohL4kBeyg+DYH0D AxRFUxTfpXGYQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH v4] PCI: Accept AtomicOps already enabled by the hypervisor Reply-To: sashiko-reviews@lists.linux.dev To: "Nikola Prica" Cc: linux-pci@vger.kernel.org In-Reply-To: <20260921111903.978687-1-nikprica@amd.com> References: <3f5fb659-c7a8-41cd-91dd-565cb46c0165@amd.com> <20260921111903.978687-1-nikprica@amd.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 21 Sep 2026 11:13:52 +0000 Message-Id: <20260921111353.0848A1F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > From: Nikola Prica >=20 > pci_enable_atomic_ops_to_root() currently fails when no Root Port is > visible. That is common in passthrough guests (ESXi, Hyper-V): the > endpoint is assigned to the VM, but the guest topology has no Root > Port above it. >=20 > In those setups the hypervisor may already have enabled AtomicOp > Requester Enable on the device. If PCI_EXP_DEVCTL2_ATOMIC_REQ is set, > treat AtomicOps as already enabled and return success instead of > failing the Root Port walk. >=20 > After 1ae8c4ce1570 ("PCI: Enable AtomicOps only if Root Port > supports them"), pci_enable_atomic_ops_to_root() always fails if the > Root Port is not visible. On systems where the Root Port is not > visible but *does* support AtomicOps, this is a regression: prior to > 1ae8c4ce1570, it enabled AtomicOps in the endpoint and returned > success. >=20 > Fixes: 1ae8c4ce1570 ("PCI: Enable AtomicOps only if Root Port supports th= em") > Reviewed-by: Christian K=C3=B6nig > Reviewed-by: Gerd Bayer > Tested-by: Gerd Bayer > Signed-off-by: Nikola Prica Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260921111903.9786= 87-1-nikprica@amd.com?part=3D1