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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?o+Bcl0kGgipqe5IgOvGIpQqDVpMDJoKW7bDJJ5d4qK3FXZG+cujTEJ6gDOc1?= =?us-ascii?Q?W64Rh2O5pYyfiosTAg/6lMk+0BtaG4qm9PfvoE6bAa5l/gpgtq18TOB35wqR?= =?us-ascii?Q?TdhEpVF2UbZz20kd4Xpa1ApARP6MiXfIk7ptdrCq+K20KXNxzpZ+7KPzo+6+?= =?us-ascii?Q?5QgkBJV6JI35512eNsjAOUrsDeXGicE+dj15IJN36vNhvTLI0SwOtjhlh4uL?= =?us-ascii?Q?VaSRebpDa3EdvXA6Q3Le2MJwaPYanUdx9FI/r3pOr5ZH/mXwyz44+7B4rv/h?= =?us-ascii?Q?7Sm/nx1QTwxpIFh96ej6V33il2T4y5RMbTw0iT8Frng5yHrUu7l7MP1qXctZ?= =?us-ascii?Q?BTZxMgQOFvlUy+Y3crswPZ0czGuTV2ZWIQLDMJUO28tI7u4/yDdOfl0JwPjd?= =?us-ascii?Q?U3mmObScBuO+WgBh0SxVV5p/YJ9lFzEKOLf2aWrlkNuQEGdkN+Y3V0E25+Yy?= =?us-ascii?Q?1Hr36btkr3FjKzj9rQISgwyAA76mbsIrtQTIBcnHbydQ5+YtAqWnKDA/fQP7?= =?us-ascii?Q?iLezzp8m1dqX9JDH7cRd8/5vxLhObDGkrjxyQUB/U/ZrgX9AUaUQLVsmHgRG?= =?us-ascii?Q?LeA2X+jiDTuD0x+c7/ygVqXYQftyGYw5k2ptI0aZFH0KXXxbtMY4y1vCs5wH?= =?us-ascii?Q?g5yIL6rDgpXSklgalUpPG6k8CV39OACgJ1QjpNS5ip4PrQTqXzpMHb0nucNL?= =?us-ascii?Q?sGcFvZijisCZ46DqYPiB2dTYyibaKrr4OlM5p9KXGhAxbPIzIedp0FgmvdRq?= =?us-ascii?Q?u0jLnOF4j5AX4Z9H3YxxqhvGzig6cf6TfbnxCI/dJAvme0GPxeFFOx8HIbMS?= =?us-ascii?Q?4zsNJ7AOrHnTqrupSqWUgwCo/+Z2DbCoA+HCMJH8kJI5Est3eknq3raLJswJ?= =?us-ascii?Q?a/xLjJWiwk0FiYdWlL15e0l//1OWvdRqfeycpCr+kiRgJpj5sMb2s9+23ZRV?= =?us-ascii?Q?UgEpD25ea8FH4uv8cx2ACNgMkwepSc1Qz7SOUh6jQSLBPXoAYJHjS4PW20VO?= =?us-ascii?Q?O3H+9Shl5G1v+YQZPy6xYMdVk9uvEdzh8PDQ3jJfQ6bx6JeVzq1mXH4dW+cF?= =?us-ascii?Q?lnrDo8LetpZnocfO8UsndLvZ9gzFsFN0BA69UYuqPWrQq9URw/b+VqmRwsmn?= =?us-ascii?Q?txJW5+vos5s3gOtOnqn/5CMaIWd4rbPj7c5Z30GgH3YouT8FsvMOqwKoNd/3?= =?us-ascii?Q?wmoR1D3RAgzxGLMt9BZO9azSxUtbVNHB/32jKO32i5ipOqWEWeZZouKQQCK0?= =?us-ascii?Q?Vf9kc16D6AcH1InsT4zbmjq9CDUGShAZWROlvsgWNe+w1b54sWiu06sjzAVf?= =?us-ascii?Q?lT1n+zhb/UqSMm99wPVtjRUPpQMwQfuAocWwHPQeYdA11TulGXgL8oyVqoU1?= =?us-ascii?Q?EF5W0xcKG9TIeoAzhkwoD/aqK9xqF1P1BEh+u48G9RSoRdHPufQVeuYaDLBX?= =?us-ascii?Q?X2fX5eVNxvGNQ6SnaYyPavZIXZPtQJsJ7Gw2+b7Fnn3xEJ+uP2knoEWL9sJZ?= =?us-ascii?Q?2TJvSYph5WEyU92GwERNdhg1i2qGCnK4BCjLQBz8JeD339kideWD75z6+Mny?= =?us-ascii?Q?08OTXdqIJCT+IDEV/205yh6N7xTDGeKGBbTcdebzhqFHYFIlTqglJioYMgtM?= =?us-ascii?Q?+gee9cCsH1dwfYOsQKEiNrUc9ONN0I9aDfooD+PLBkH/vwaLIGCKPuJOVh5V?= =?us-ascii?Q?7sKrqz3EmMCtYSOStRHBDG50W4z18Tr9voVOKTPoK1X609yb?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: cbaf8d7e-2ac4-45e0-c594-08df100a7eba X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Sep 2026 13:42:17.3260 (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: JCzjzvirBsbM7Sat6RbzW4QsQFEi359vnRA9F6DNtJM/qWcPVmkbmAOyINwW9Osw7S289sKgs3qcmpYXeiAC2g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6849 On Thu, Sep 10, 2026 at 08:03:03PM -0700, Borislav Petkov wrote: > On Thu, Sep 03, 2026 at 02:37:08PM -0500, Serge Hallyn (AMD) wrote: > > On Thu, Sep 03, 2026 at 10:43:25AM -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. > > Ontop of this: > > From: "Borislav Petkov (AMD)" > Date: Thu, 10 Sep 2026 18:43:33 -0700 > Subject: [PATCH] x86/topo: Initialize AMD nodes per package > > Sashiko reports that > > If amd_num_nodes() evaluates to 0, kzalloc_objs(*amd_roots, 0) returns the > truthy ZERO_SIZE_PTR (typically (void *)16). > > Because ZERO_SIZE_PTR is not NULL, the subsequent check for !amd_roots will > fail to catch it, resulting in a divide-by-zero kernel panic on the very > next line during the __init boot phase. > > Make sure topology_amd_nodes_per_pkg() doesn't return 0 - the AMD nodes per > package count can be trivially 1 if detection fails just like the rest > of the max* and num* packages topology attributes. > > Closes: https://sashiko.dev/#/patchset/20260903154325.74343-1-yazen.ghannam%40amd.com > Signed-off-by: Borislav Petkov (AMD) > --- > arch/x86/kernel/cpu/topology_common.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/cpu/topology_common.c b/arch/x86/kernel/cpu/topology_common.c > index 6845e3c63fbb..7a7442981594 100644 > --- a/arch/x86/kernel/cpu/topology_common.c > +++ b/arch/x86/kernel/cpu/topology_common.c > @@ -14,7 +14,7 @@ > struct x86_topology_system x86_topo_system __ro_after_init; > EXPORT_SYMBOL_GPL(x86_topo_system); > > -unsigned int __amd_nodes_per_pkg __ro_after_init; > +unsigned int __amd_nodes_per_pkg __ro_after_init = 1; > EXPORT_SYMBOL_GPL(__amd_nodes_per_pkg); > > /* CPUs which are the primary SMT threads */ > -- Reviewed-by: Yazen Ghannam Thanks, Yazen