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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xoIcglV6499EsaZxcY8rFA0kCzvTcUFPSE2ogUcZ6v+kX+5Ek6Phzj/lbxlT?= =?us-ascii?Q?Hgg++NuqtZSlznNYkKbjA8VmBX5IncuBxHZWco0o0cMbc+EctCWCgA833Y36?= =?us-ascii?Q?BItgDqeh5E74UlpQNvRl0J8eD76gROZtJlxW+AVjE0jw/sEnUuAdskXQJwgV?= =?us-ascii?Q?xldqh590ToOkJTochKzVUtC1sqDaY+EFXIyV8fY+LvCvLRNymuUvtUTcEegC?= =?us-ascii?Q?lardFYHBFg1n2lrXm9z39Uc+fr24LT9h062XSyICJs5ZD9pXbuEZzh1CRYn9?= =?us-ascii?Q?QAN+oSgBv23TljUpsF5E0e3HICQijHxrEKDCzIggVRomYltxlMKBQhV6e2z1?= =?us-ascii?Q?gpaCFB1owBWjQKGz1sJVhf/QIplkx28V07q2r0w3+aiYMrJ+UJ2hwaIimWsa?= =?us-ascii?Q?ciFU0MgabFTj7UUNmwD9ELN+P3IYAQ/3GvGHkQAyVp8fLVkatNxF6qESzpg7?= =?us-ascii?Q?zKnbxWmra9RvDiy4Ct7VFTkOW9MTshzM5b1MKONZDP+uT+EcM5VbF/bG58SG?= =?us-ascii?Q?smOxJirxEsTwM5t46Ku4u+PA6fK8L8qQbHVRcawgtj9UjXfsshuMEnKmDbLI?= =?us-ascii?Q?KhoqKfecSqwPP0bNLwMoXM95hjnKh+/pl8kVUPP6BZTt9CGZRrGORHsRV/WR?= =?us-ascii?Q?Z/Axaxf6IwAoiD4AP1+d2SzT1u7AKjSFfnkRv16ENTOg3NIditrgwZHH5tlA?= =?us-ascii?Q?O5gCHmtj3map4c2BDU5+7+b4XTcxIPtVKym9Zlwj+b/rYuq4Z92Sj8aZvbZc?= =?us-ascii?Q?px1u2zPxN91Vux7/xnT3bUwbxSRon7d4YP+UTQCiGnfM8W/PkmDhj+jSvQb5?= =?us-ascii?Q?tB190ew6e2PaUVdSsZrdE0y3A5AMPyCjEigcVSEQS26xYLU0LAAC8WGApMOC?= =?us-ascii?Q?jAvRSmDfoGoor7vfVMdoGzlf7C5lilzLy2kyk9xnF+4U1fzFa1Y6vn4Wk5mr?= =?us-ascii?Q?6JEqUs4EU0FBpE6nIbax48P1T5btdnPVg/B+irzfhiXgm8kIDLKsSXxB1Vr9?= =?us-ascii?Q?mP3BohCgceHlZpGLS4WsR0/HREmSm4LiXNPjsZ3rb9X3IN6ANEMIq/xev4YC?= =?us-ascii?Q?se6d1Bpi+wlUB8MA4qelI5MgQj1ycYBM+1BKdLOcXIODo8y9gXIB3stkjyR4?= =?us-ascii?Q?AFJiG+4c2tHmAECmUW7qXsLBxZ+DZQ00P21jwmVMzvuGH1Mtc92gOO6XGIc/?= =?us-ascii?Q?qkaUwLUf9mEti7JBx0bGecI52tyzqTCioUfp1n0pVm8AedHX4MPsPOEXqUgS?= =?us-ascii?Q?yKD3HDqku1znxVPHt83dCG5EsRfoFVffRu9w6gN+hW4zCMWaXTFHbUuDy4m4?= =?us-ascii?Q?NeYD6ioUCnY7xW32BuTJ3aTWiwU7GRAmruNvmSb6VWSni7izGLvBE0AVxIUi?= =?us-ascii?Q?o+o/SeRfbg0FLzdPmiUWtBUDM7c+def1LN/f9YPeyCzWoPU4pkLrsU3CduGW?= =?us-ascii?Q?IfIfS2pPPNvtNrVs9S9QyVySP/ZVDlrBeesWowzB0zjnPDC78EJWSElJF5t7?= =?us-ascii?Q?OrFaHUVnbZWwC3Xe97aIPBDt0dLIfzGnD2jSbZr3ovxK5tOgfkqxJOeK8GCh?= =?us-ascii?Q?yKIq+1+f7YAK1Uv6LvEu2hCufHOCzxEFX4+ynIct4o5JdIIujx789bsHFN+v?= =?us-ascii?Q?KHOiT+G4ztZ6i2Fc3OOyNFPz/WqvhXWiyVnSYZkGNH8gUgOCvHaFyUSgMUj6?= =?us-ascii?Q?ArtfXkLKgug9ci9F/xhpTIriMrDVraQAqKKau9/M/RMjr+k3?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 17bdf0b2-f17e-4361-aa98-08df02b6263c X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2026 14:35:46.0512 (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: kOSCp39MdlkE4RMBHSS6n9qdl+Ew0/dEowguz76JoN53VcTph0pRZWxAr+LD8E7tjGKkqRgFxrJCaPIKkmVNgA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB5657 On Tue, Aug 25, 2026 at 09:52:06AM -0400, Yazen Ghannam wrote: > 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. > Actually, this isn't an issue. An exhaustive search ends with a NULL pointer. The PCI search helpers would have done the 'put' on the last device. This also means that the second 'root = NULL' is redundant. I'll remove it in the next revision. Please let me know what you think. Thanks, Yazen