From: Wang ShaoBo bobo.shaobowang@huawei.com
mainline inclusion from mainline-v5.16-rc1 commit 4cc4cc28ec4154c4f1395648ab67ac9fd3e71fdc category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4WA1K CVE: NA
--------------------------------
When testing cpu online and offline, warning happened like this:
[ 146.746743] WARNING: CPU: 92 PID: 974 at kernel/sched/topology.c:2215 build_sched_domains+0x81c/0x11b0 [ 146.749988] CPU: 92 PID: 974 Comm: kworker/92:2 Not tainted 5.15.0 #9 [ 146.750402] Hardware name: Huawei TaiShan 2280 V2/BC82AMDDA, BIOS 1.79 08/21/2021 [ 146.751213] Workqueue: events cpuset_hotplug_workfn [ 146.751629] pstate: 00400009 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 146.752048] pc : build_sched_domains+0x81c/0x11b0 [ 146.752461] lr : build_sched_domains+0x414/0x11b0 [ 146.752860] sp : ffff800040a83a80 [ 146.753247] x29: ffff800040a83a80 x28: ffff20801f13a980 x27: ffff20800448ae00 [ 146.753644] x26: ffff800012a858e8 x25: ffff800012ea48c0 x24: 0000000000000000 [ 146.754039] x23: ffff800010ab7d60 x22: ffff800012f03758 x21: 000000000000005f [ 146.754427] x20: 000000000000005c x19: ffff004080012840 x18: ffffffffffffffff [ 146.754814] x17: 3661613030303230 x16: 30303078303a3239 x15: ffff800011f92b48 [ 146.755197] x14: ffff20be3f95cef6 x13: 2e6e69616d6f642d x12: 6465686373204c4c [ 146.755578] x11: ffff20bf7fc83a00 x10: 0000000000000040 x9 : 0000000000000000 [ 146.755957] x8 : 0000000000000002 x7 : ffffffffe0000000 x6 : 0000000000000002 [ 146.756334] x5 : 0000000090000000 x4 : 00000000f0000000 x3 : 0000000000000001 [ 146.756705] x2 : 0000000000000080 x1 : ffff800012f03860 x0 : 0000000000000001 [ 146.757070] Call trace: [ 146.757421] build_sched_domains+0x81c/0x11b0 [ 146.757771] partition_sched_domains_locked+0x57c/0x978 [ 146.758118] rebuild_sched_domains_locked+0x44c/0x7f0 [ 146.758460] rebuild_sched_domains+0x2c/0x48 [ 146.758791] cpuset_hotplug_workfn+0x3fc/0x888 [ 146.759114] process_one_work+0x1f4/0x480 [ 146.759429] worker_thread+0x48/0x460 [ 146.759734] kthread+0x158/0x168 [ 146.760030] ret_from_fork+0x10/0x20 [ 146.760318] ---[ end trace 82c44aad6900e81a ]---
For some architectures like risc-v and arm64 which use common code clear_cpu_topology() in shutting down CPUx, When CONFIG_SCHED_CLUSTER is set, cluster_sibling in cpu_topology of each sibling adjacent to CPUx is missed clearing, this causes checking failed in topology_span_sane() and rebuilding topology failure at end when CPU online.
Different sibling's cluster_sibling in cpu_topology[] when CPU92 offline (CPU 92, 93, 94, 95 are in one cluster):
Before revision: CPU [92] [93] [94] [95] cluster_sibling [92] [92-95] [92-95] [92-95]
After revision: CPU [92] [93] [94] [95] cluster_sibling [92] [93-95] [93-95] [93-95]
Fixes: c5e22feffdd7 ("topology: Represent clusters of CPUs within a die") Signed-off-by: Wang ShaoBo bobo.shaobowang@huawei.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Reviewed-by: Dietmar Eggemann dietmar.eggemann@arm.com Acked-by: Barry Song song.bao.hua@hisilicon.com Tested-by: Dietmar Eggemann dietmar.eggemann@arm.com Link: https://lore.kernel.org/r/20211110095856.469360-1-bobo.shaobowang@huawei.com Reviewed-by: Cheng Jian cj.chengjian@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/base/arch_topology.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 21e63b6fab83..0d19fe5c99d4 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -586,6 +586,8 @@ void remove_cpu_topology(unsigned int cpu) cpumask_clear_cpu(cpu, topology_core_cpumask(sibling)); for_each_cpu(sibling, topology_sibling_cpumask(cpu)) cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling)); + for_each_cpu(sibling, topology_cluster_cpumask(cpu)) + cpumask_clear_cpu(cpu, topology_cluster_cpumask(sibling)); for_each_cpu(sibling, topology_llc_cpumask(cpu)) cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));