In the Linux kernel, the following vulnerability has been resolved: rcu-tasks: Fix access non-existent percpu rtpcp variable in rcutasksneedgpcb() For kernels built with CONFIGFORCENRCPUS=y, the nrcpuids is defined as NRCPUS instead of the number of possible cpus, this will cause the following system panic: smpboot: Allowing 4 CPUs, 0 hotplug CPUs ... setuppercpu: NRCPUS:512 nrcpumaskbits:512 nrcpuids:512 nrnodeids:1 ... BUG: unable to handle page fault for address: ffffffff9911c8c8 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 15 Comm: rcutaskstrace Tainted: G W 6.6.21 #1 5dc7acf91a5e8e9ac9dcfc35bee0245691283ea6 RIP: 0010:rcutasksneedgpcb+0x25d/0x2c0 RSP: 0018:ffffa371c00a3e60 EFLAGS: 00010082 CR2: ffffffff9911c8c8 CR3: 000000040fa20005 CR4: 00000000001706f0 Call Trace: <TASK> ? _die+0x23/0x80 ? pagefaultoops+0xa4/0x180 ? excpagefault+0x152/0x180 ? asmexcpagefault+0x26/0x40 ? rcutasksneedgpcb+0x25d/0x2c0 ? _pfxrcutaskskthread+0x40/0x40 rcutasksonegp+0x69/0x180 rcutaskskthread+0x94/0xc0 kthread+0xe8/0x140 ? _pfxkthread+0x40/0x40 retfromfork+0x34/0x80 ? _pfxkthread+0x40/0x40 retfromforkasm+0x1b/0x80 </TASK> Considering that there may be holes in the CPU numbers, use the maximum possible cpu number, instead of nrcpu_ids, for configuring enqueue and dequeue limits. [ neeraj.upadhyay: Fix htmldocs build error reported by Stephen Rothwell ]