{"id":"CVE-2022-49090","summary":"arch/arm64: Fix topology initialization for core scheduling","details":"In the Linux kernel, the following vulnerability has been resolved:\n\narch/arm64: Fix topology initialization for core scheduling\n\nArm64 systems rely on store_cpu_topology() to call update_siblings_masks()\nto transfer the toplogy to the various cpu masks. This needs to be done\nbefore the call to notify_cpu_starting() which tells the scheduler about\neach cpu found, otherwise the core scheduling data structures are setup\nin a way that does not match the actual topology.\n\nWith smt_mask not setup correctly we bail on `cpumask_weight(smt_mask) == 1`\nfor !leaders in:\n\n notify_cpu_starting()\n   cpuhp_invoke_callback_range()\n     sched_cpu_starting()\n       sched_core_cpu_starting()\n\nwhich leads to rq-\u003ecore not being correctly set for !leader-rq's.\n\nWithout this change stress-ng (which enables core scheduling in its prctl\ntests in newer versions -- i.e. with PR_SCHED_CORE support) causes a warning\nand then a crash (trimmed for legibility):\n\n[ 1853.805168] ------------[ cut here ]------------\n[ 1853.809784] task_rq(b)-\u003ecore != rq-\u003ecore\n[ 1853.809792] WARNING: CPU: 117 PID: 0 at kernel/sched/fair.c:11102 cfs_prio_less+0x1b4/0x1c4\n...\n[ 1854.015210] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010\n...\n[ 1854.231256] Call trace:\n[ 1854.233689]  pick_next_task+0x3dc/0x81c\n[ 1854.237512]  __schedule+0x10c/0x4cc\n[ 1854.240988]  schedule_idle+0x34/0x54","modified":"2026-04-02T08:27:17.519751Z","published":"2025-02-26T01:54:46.227Z","related":["SUSE-SU-2025:1027-1","SUSE-SU-2025:1176-1","SUSE-SU-2025:1183-1","SUSE-SU-2025:1241-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49090.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/5524cbb1bfcdff0cad0aaa9f94e6092002a07259"},{"type":"WEB","url":"https://git.kernel.org/stable/c/790c1567582bda8f1153015436e3330a7c6eb278"},{"type":"WEB","url":"https://git.kernel.org/stable/c/87f5d66daa5f457449bb95d6b8d18bb7596aa627"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c78a1b2d0bff678570c8dc9f14035606f5e5257d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49090.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-49090"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"9edeaea1bc452372718837ed2ba775811baf1ba1"},{"fixed":"87f5d66daa5f457449bb95d6b8d18bb7596aa627"},{"fixed":"790c1567582bda8f1153015436e3330a7c6eb278"},{"fixed":"c78a1b2d0bff678570c8dc9f14035606f5e5257d"},{"fixed":"5524cbb1bfcdff0cad0aaa9f94e6092002a07259"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49090.json"}}],"schema_version":"1.7.5"}