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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?HXs7ITzs3b2u2AIV/XsbAFqrZjEWOMUmjG5/djcfVHhLfdfl0BCUm2EZGijl?= =?us-ascii?Q?xmV2k2Cou2Gis3jHaSm98JJYcZ4Xlt7Z8OEUJ6mD4eD+zIpRW09XRgRhIpE7?= =?us-ascii?Q?Q/U2b90NWf0KcS5fYTLvf9R4DJTDFa10kW5D5lWRHwfPowu1vbsaSyMrPSNr?= =?us-ascii?Q?MkM/JQKeQYaTpF30NUl72Jn7tNWhc6HHPoMV9KF6pnZ8DE56LQ6uuzM07wJw?= =?us-ascii?Q?sopbP6EPQpUtpwK6GBssA/c6eVG1xjg1Cdw6kmqTG8FuC/J4Tsv/muEKMVpK?= =?us-ascii?Q?p0b8aev5eR/mR+pZfHJe6s0ITxIO0xhoxdiAtghFBzTxy6YBV2YfGAygpSsB?= =?us-ascii?Q?8/LTgXMji5LGajjtoyH5WRVK6ccZGoq89z1qxuZuec37GdJd+MpDZRL+AbFf?= =?us-ascii?Q?ipydcxkUS0D2RmmrVjvjalwyGFQva8eEkqBFOffudJDa7NyK/Ef3niiycioZ?= =?us-ascii?Q?ySAJajh0xd2YRcN5Q9/hha2N2zKtGTlUm0Jjve0lbSi8YrTR7f7NnHWoy2OZ?= =?us-ascii?Q?RToEzD0td4h9ve+NUIblaJH/D8gdJZFWOmsPaJJVH+UuUkYkzZF5sMKDviMp?= =?us-ascii?Q?z8eDE7Dm/7Tp26HLnkepoc0oS0C16PjAm0whW8apPsnz/5ra6o4VdyG/jnXq?= =?us-ascii?Q?7ZeFryryDyDGVPlmpn+GU2Kv8c66p5ILhA9sE8FFhV33WCHPfQu2CDAG/J9Q?= =?us-ascii?Q?AVP/uxF3zuoZJYgNnbv+floB2MPdxLdEOjREHmoFLtNkYSZYdv6QW42A7bkZ?= =?us-ascii?Q?votwPnNQUVbC48R3PPaxn2T1r+CbNfr2IpUw0ggFzOTtva9V7QDKHzqCBBkT?= =?us-ascii?Q?PODvAC+Ve+dNdLghKOxd/UF+6rFZmXmq/elgOkw5lGSL50An5CmPpFozRF4v?= =?us-ascii?Q?R7tAj3Q5M6pm2VLduOoIjB4YizNjdoycSTQdI9yk+o21Vb4WFbBqkXUiPEPD?= =?us-ascii?Q?9I7gHocUTsQk7x0n9SDqpovPJcqpQ3hq6blyB0zmDFkkxLtStGib9b2C5lvM?= =?us-ascii?Q?i41a0CNxDwEmLDgm2E+hkYwX4eFbQp2qysEiNKGMHjvdHdJ6PflcUZINswse?= =?us-ascii?Q?QpGldWhw8dRiA5R77Hs7cDw/43OjDbHLtayKITGFkGcsHx9vzJlDnMYjbheI?= =?us-ascii?Q?809S0iQF6IEnivy3xsBcW422QWqsMClAeM/kxbTp5zobrgp4WNhaYBtwbI9h?= =?us-ascii?Q?CrNGRG4NL5YVDfpCe2ZgHVlsJv9ikXKjX3O+Tx+OSdDi4loHSD+v5EueHziN?= =?us-ascii?Q?hoZuyib+/6tg//p+TP0Qwh9Lfab3Chk03TLBEjXeaZgFJCvsYjjbakJodVIQ?= =?us-ascii?Q?6PvyRIZD+kX7WZncjPDHs2KgEhYp34ctwNdKt1HSV2hq+B2/h51odngVuQKC?= =?us-ascii?Q?Qu/xS72XqdM8Zi4NyW0T4TqfEcmeibbeFjgQ+zjHQ1UzyfYjkctfI6Bavnby?= =?us-ascii?Q?wS11+QjsGLGnovqO16UL9x4FU7iTYcsmhCubzkQtDxydDp/baBYHgoLgwOHC?= =?us-ascii?Q?91k7Dg6VdzL9XW/JGJO2Y9j+nEif2HC3wJbzNkE4toCFOfaOKY2+SqssrDWb?= =?us-ascii?Q?xJPppsjPfWm9OwR4z6qyEXYnh1HH0AdCOIx7sCTC2FDfsGgSXWRmOy8cdT+e?= =?us-ascii?Q?7nL8N8he5AEjBSH5tmbFg6rVOeQl9Oda/z/0m172cbVhi8sRp52GuvUZLah0?= =?us-ascii?Q?TSCQ5jeXPpfwUqgv/dNQ8BossfGuhaGyoPEv1PGkEoM4zVEV?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: a9ffb426-9657-4bdf-58c6-08df39e72252 X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Nov 2026 20:14:58.7710 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: xz/EhoQuQBVnqE4ji/PMgZlXU9Z/Z+M3Uk9VRWFF2lLT4Fpn8LxMyZybC9Y2Fgc+Q1EzipF2Wm0a5hlQuN794g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB9176 On Tue, Oct 20, 2026 at 11:19:19AM -0700, Kuppuswamy Sathyanarayanan wrote: > From: Lukas Wunner > > Downstream Port Containment does not mandate presence of an Advanced Error > Reporting capability, so a Downstream Port may support DPC, but not AER > (PCIe r7.1 sec 6.2.11.2). > > Commit 708b20003624 ("PCI/AER: Remove HEST/FIRMWARE_FIRST parsing for AER > ownership") seemingly inadvertently constrained DPC to AER-supporting > Downstream Ports by inserting a call to pcie_aer_is_native() in > dpc_probe(), which implicitly checks for presence of an AER capability. > > Drop the call. It is superfluous because it duplicates the conditions > applied by the PCIe port service driver when it decides whether to > instantiate a DPC port service (see get_port_device_capability()). > If the conditions are not met, no port service is instantiated and > dpc_probe() isn't executed. > > The only difference between the conditions in dpc_probe() and the ones in > get_port_device_capability() is the check for the AER capability, so by > removing the checks from dpc_probe(), DPC is supported on AER-incapable > Downstream Ports again. > > Fixes: 708b20003624 ("PCI/AER: Remove HEST/FIRMWARE_FIRST parsing for AER ownership") > Signed-off-by: Lukas Wunner > Cc: stable@vger.kernel.org # v5.8+ Another open question from the other set: https://lore.kernel.org/all/02a33171-b901-400b-921a-c40fe167b424@linux.intel.com/ Maybe the issue is more about how to handle the Fixes tag? The recent commit is where this seems to functionally break. The older commit is where this logically broke. > --- > drivers/pci/pcie/dpc.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c > index 793a799053f1..104ff2b91f1f 100644 > --- a/drivers/pci/pcie/dpc.c > +++ b/drivers/pci/pcie/dpc.c > @@ -474,9 +474,6 @@ static int dpc_probe(struct pcie_device *dev) > int status; > u16 cap; > > - if (!pcie_aer_is_native(pdev) && !pcie_ports_dpc_native) > - return -ENOTSUPP; > - > status = devm_request_threaded_irq(device, dev->irq, dpc_irq, > dpc_handler, IRQF_SHARED, > "pcie-dpc", pdev); > -- But I agree this is okay otherwise. Reviewed-by: Yazen Ghannam Thanks, Yazen