On 28/11/2014 03:38, Gonglei wrote: >> > Can you find what line of kernel/sched.c it is? > Yes, of course. See below please: > "sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power; " > in update_sg_lb_stats(), file sched.c, line 4094 > And I can share the cause of we found. After commit 787aaf57(target-i386: > forward CPUID cache leaves when -cpu host is used), guest will get cpu cache > from host when -cpu host is used. But if we configure guest numa: > node 0 cpus 0~7 > node 1 cpus 8~15 > then the numa nodes lie in the same host cpu cache (cpus 0~16). > When the guest os boot, calculate group->cpu_power, but the guest find thoes > two different nodes own the same cache, then node1's group->cpu_power > will not be valued, just is the initial value '0'. And when vcpu is scheduled, > division by 0 causes kernel panic.
Thanks. Please open a Red Hat bugzilla with the information, and Cc Larry Woodman <lwood...@redhat.com> who fixed a few instances of this in the past. Paolo
