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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Yqp8pynvmz0NgZ29wJvyjvOCJxKFzbQovRk5uoStkfFHLMVE59FO+qn7ErHA?= =?us-ascii?Q?J2jf/F49kJDPbPJfcNIHO4sk/RJKZs16h43C2Q9aEv5wEXsn9XxJaw+d9gFf?= =?us-ascii?Q?Erx8hKGUpzhfAMJ4mkAYCC/vq9Veu68pC33/gVwQlQyUfswDsaJMcvPMJZAa?= =?us-ascii?Q?eOAt4802LRghRLY+8B83Z1qoZxK6Hsq7Lh/vo6sx/0VFE3zDa3V3kddTRSRE?= =?us-ascii?Q?drpXRynDUS7rtL3AfsoYXVI1EccqFb1R4N77DeCVmYbcc4P5NdQrTAH2nR2O?= =?us-ascii?Q?HHiWqN2TtyVOl4LFRO6bCwwhEiiRg4hfbrIU4Ok1mdkBxvh+e/+zw9+u8PbP?= =?us-ascii?Q?IKBtw4vImag9LX3uloWgovQL2PlYIIAmpKgfQp362+OwioKciem+baeCeNou?= =?us-ascii?Q?cfWSsQ5QDQ6iFq9M0CcXsW4fpmm0akVTC/S/+8AYIsaHELI7rXxX3D6wLncC?= =?us-ascii?Q?lQGOImcL83EnluoXKgFJd2C/yh9BciUMxyaYSlmHC4ZD2UneFrk/N3OYmk0L?= =?us-ascii?Q?PVyCPMfJFlkBTk7/8oyqtnxEXZWkBnDgzLUs2zlo69EErg51UfdVmscYDM6p?= =?us-ascii?Q?cdLV1khkNmnjchA2cqf+CqYrJtT8weX30P43wHdi8fMd2aroRTxMOV1Uz/sq?= =?us-ascii?Q?i8sGZpX4/8a8YkjFqLS5kWZq/zRMTa5z9sbbu/V0uOHU9+JgTNBIFVTEOIVh?= =?us-ascii?Q?OD1wVm4yoT0rVxiXqAp3y6LGAvPrYFAtxocB/TCIPsjqFTzFsQ4M/TEHaIxG?= =?us-ascii?Q?4/6r5tKnCd0UbdpKIXlYQF+iXHpPsIGTObjINvk5JrM6C3cNRKiSqGApnf7V?= =?us-ascii?Q?/fqQchVlobWw5CorM5SmSsVu3KQlDDHSdCv/EZ9UBAyOcOS22JDkSFhjsxrH?= =?us-ascii?Q?yK/VValmtLROvKL5OJ6YSKpn1519SzZhJREnwtivScg9tuSnVydShcUBF7dH?= =?us-ascii?Q?2XBAot5x9S5Gm9TC4rwmBnA5sOnLlpapKD2cbdAHWIdWsmKsjKypnRbwxNjl?= =?us-ascii?Q?njHivQLLB87I9GHHhnxUyY1wvZxxq0zLos8SB1DwC1JYnHtAsJe1pqpT/uHN?= =?us-ascii?Q?8PFU+DX3t2qogoc83fyUX/v/vpSbv6nJmedmJiTJZYuiJT/kSgzAU/SRrCOK?= =?us-ascii?Q?Y53YV1r69LMi8gkdQdfvr8caRDoj3zGZDAUDr2RwlLbiuuB+Nzqg/0oy6sLh?= =?us-ascii?Q?yw7PlnQmTWmK8J60zUSpLymIFEmK9vjF33Mr8wODczMSkvalt2vv+69cm0sy?= =?us-ascii?Q?hEui9bnTlqCxrcW/wdKG5+ajrp/OZ+D3YHxUnYQPd4wqdzPIOEkfXGGTs0Fn?= =?us-ascii?Q?NEN1fIi7sOSN2XwYob4vDk7z8ocKN5gzZXCHrU33i03scpS8sX2jdpOj/jh/?= =?us-ascii?Q?0PDz9zTvv0nlO/ZQLe3xWuIQcP2rDfOAkUA+YnWGeeLoi4dtjK/nMmd9a8HD?= =?us-ascii?Q?Nls0f4RmjoJbaqx652F8MMLERqHe0FXHl8YPE2BLULwPQb7QD6zHvC6op3+7?= =?us-ascii?Q?Jk5VPdFOLR80jOWXBGurdPIeDUPYBA8ZwQzdoNK6VQVrClpTQpHyJp6gY5Ri?= =?us-ascii?Q?hzMkmsDEgZNXVqIlGC1Dq07VVL/8kw0xOUcTGus+eFuaKhPJUDtJ9quz6ifq?= =?us-ascii?Q?G5D/H6wv6nTZrn9XC3I7dHEdH4HoFYXaTyp9rH/1yLWA+y8/o0JYuI7FYSaR?= =?us-ascii?Q?avqrJNRpgz2ClkOedVxMe7ZMrFHUtwXDVTJ88efOB6aU6lIU?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: d1dcc4ae-b34a-4358-becd-08df02b011be X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2026 13:52:14.6771 (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: poRUT0o6sjhDVNKPDx8gdLQzq3MLMvo6EMNR7MMbni2PRGs/d6SnADuko+J9vF73NHOKTKuSSV4un5F7qqdchw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB7665 On Mon, Aug 24, 2026 at 10:59:28PM -0500, Serge Hallyn (AMD) wrote: > On Mon, Aug 24, 2026 at 12:50:03PM -0500, Yazen Ghannam wrote: > > The local "root" pointer is a temporary variable used during the device > > search. Therefore, refcount related to the search iterators should be > > cleaned up after the search is complete. > > > > Use the __free() cleanup macro to ensure the refcount is decremented > > when the temporary pointer goes out of scope. > > > > Additionally, increment the refcount when caching a root pointer. This > > ensures the in-use refcount is separate from the temporary search > > refcounting. > > > > Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") > > Reported-by: Sashiko > > Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com > > Assisted-by: Claude-Code:claude-opus-5 > > Signed-off-by: Yazen Ghannam > > --- > > arch/x86/kernel/amd_node.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/arch/x86/kernel/amd_node.c b/arch/x86/kernel/amd_node.c > > index 0be01725a2a4..312adf73313b 100644 > > --- a/arch/x86/kernel/amd_node.c > > +++ b/arch/x86/kernel/amd_node.c > > @@ -247,7 +247,7 @@ __setup("amd_smn_debugfs_enable", amd_smn_enable_dfs); > > static int __init amd_smn_init(void) > > { > > u16 count, num_roots, roots_per_node, node, num_nodes; > > - struct pci_dev *root; > > + struct pci_dev *root __free(pci_dev_put) = NULL; > > > > if (!cpu_feature_enabled(X86_FEATURE_ZEN)) > > return 0; > > @@ -258,7 +258,6 @@ static int __init amd_smn_init(void) > > return 0; > > > > num_roots = 0; > > - root = NULL; > > while ((root = get_next_root(root))) { > > pci_dbg(root, "Reserving PCI config space\n"); > > > > Will this leak the ref taken on the last get_next_root(root) in the > first loop? You might need a pci_dev_put(root) before the root = NULL > above the second loop. Or I could be wrong. > Yes, I think you're right. Good catch. I'll send another revision with your suggestion. Thanks, Yazen