From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C17933F211C; Thu, 2 Apr 2026 16:38:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775147922; cv=none; b=FbaFtfGcVj5hvu0EG91QWcIvhLRWtwJl71zVKo3h0adLC/nRqeOPpU4dAIxIztuRAyk0C42wysbW9f3CN+LZVc+aVHQjA1p6DvNQ9UXaaMr2k5zqnGieb32BIcUE3neka4AooLfCB+qZZ97KhJCLQSYUr9AHsm+O/4p853czvK4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775147922; c=relaxed/simple; bh=SS+BtVdttMvo6X20fLR3JClq/W5wC0bvQxoXCy/55dc=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=ltqt2wDRJoBK05JjK+J50RfPayuCabZr4F35/tbp8WHV2iKyDBBKZ1MwYlOlmFXbKe2ZHdoNHZC10f0d3BlPCf3UjRAjjgEJuyo6E5klux5X1MqMCtbfge3LptRFCzx0jD5WpsXSi6ZI0fJ5AGQq1oegr6SenPZSJaib+qEJbhw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=U3vICxvM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="U3vICxvM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDE30C116C6; Thu, 2 Apr 2026 16:38:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775147922; bh=SS+BtVdttMvo6X20fLR3JClq/W5wC0bvQxoXCy/55dc=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=U3vICxvMqgBh7amR+oCizO3AJ7YOv3bxzO8OCsh6ZNB5XW45uHJ/8h8WJx54f1P91 xDmPSvdX9WiW9SuHdR2YUbGunbzjakgfC9lpI1iEHTaYHIZ3/27UQhAdF5d8lWlB1x Pd5ZE1JHkCSZ9qd9lw5ug60ehF3zJp/hs6R1OwWeq/rWlnIZq277RkUEVs2UadCRmq K58kn3MHghtAlrqMVicW2YdHuCFzNec/LSZEHYXCPZmAh/+BkYJmoaCfBR6PS8wfU8 uWou+k7OQkgxGJ5V+67qVIGW3r+gVfCohHAvry1cjRT3YXi9BZAFZ34kvNTES8g39K D+hKMQ+afiejw== Date: Thu, 2 Apr 2026 11:38:40 -0500 From: Bjorn Helgaas To: Gerd Bayer Cc: Bjorn Helgaas , Jay Cornwall , Felix Kuehling , Ilpo =?utf-8?B?SsOkcnZpbmVu?= , Christian Borntraeger , Niklas Schnelle , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Sven Schnelle , Leon Romanovsky , Alexander Schmidt , linux-s390@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v7 0/3] PCI: AtomicOps: Fix pci_enable_atomic_ops_to_root() Message-ID: <20260402163840.GA279690@bhelgaas> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260330-fix_pciatops-v7-0-f601818417e8@linux.ibm.com> On Mon, Mar 30, 2026 at 03:09:43PM +0200, Gerd Bayer wrote: > Hi Bjorn et al. > > On s390, AtomicOp Requests are enabled on a PCI function that supports > them, despite the helper being ignorant about the root port's capability > to supporting their completion. > > Patch 1: Do not enable AtomicOps Requests on RCiEPs > Patch 2: Fix the logic in pci_enable_atomic_ops_to_root() > Patch 3: Update references to PCIe spec in that function. > > I did test that the issue is fixed with these patches. Also, I verified > that on a Mellanox/Nvidia ConnectX-6 adapter plugged straight into the > root port of a x86 system still gets AtomicOp Requests enabled. > > Due to a lack of the required hardware, I did not test this with any PCIe > switches between root port and endpoint. So test exposure in other > environments is highly appreciated. > > Signed-off-by: Gerd Bayer Thanks, applied to pci/atomics for v7.1 with minor rework of 2/3. > --- > Changes in v7: > - Prepend series with a patch to explicitly exclude RCiEPs from > enablement of AtomicOps Requests > - Limit the core patch 2 to enforce a full check of the entire > PCIe hierarchy for support of AtomicOps capabilities. > - Rebase to v7.0-rc6 > - Link to v6: https://lore.kernel.org/r/20260325-fix_pciatops-v6-0-10bf19d76dd1@linux.ibm.com > > Changes in v6: > - Incorporate Ilpo's editorial comments. > - Correct logic in pci_is_atomicops_capable_rp() (annotated by Sashiko) > - Link to v5: https://lore.kernel.org/r/20260323-fix_pciatops-v5-0-fada7233aea8@linux.ibm.com > > Changes in v5: > - Introduce new pcibios_connects_to_atomicops_capable_rc() so arch's can > declare AtomicOps support outside of PCIe config space. Defaults to > "true" - except s390. > - rebase to 7.0-rc5 > - Link to v4: https://lore.kernel.org/r/20260313-fix_pciatops-v4-0-93bc70a63935@linux.ibm.com > > Changes in v4: > - drop patch 1 - it will become the base of a new series > - previous patch 2, now 1: reword commit message > - add a new patch to update references to PCI spec within > pci_enable_atomic_ops_to_root() > - rebase to latest master > - Link to v3: https://lore.kernel.org/r/20260306-fix_pciatops-v3-0-99d12bcafb19@linux.ibm.com > > Changes in v3: > - rebase to 7.0-rc2 > - gentle ping > - add netdev and rdma lists for awareness > - Link to v2: https://lore.kernel.org/r/20251216-fix_pciatops-v2-0-d013e9b7e2ee@linux.ibm.com > > Changes in v2: > - rebase to 6.19-rc1 > - otherwise unchanged to v1 > - Link to v1: https://lore.kernel.org/r/20251110-fix_pciatops-v1-0-edc58a57b62e@linux.ibm.com > > --- > Gerd Bayer (3): > PCI: AtomicOps: Do not enable requests by RCiEPs > PCI: AtomicOps: Do not enable without support in root port > PCI: AtomicOps: Update references to PCIe spec > > drivers/pci/pci.c | 48 ++++++++++++++++++++++++++---------------------- > 1 file changed, 26 insertions(+), 22 deletions(-) > --- > base-commit: 7aaa8047eafd0bd628065b15757d9b48c5f9c07d > change-id: 20251106-fix_pciatops-7e8608eccb03 > > Best regards, > -- > Gerd Bayer >