Messages in this thread | | | Subject | Re: [PATCH v4] x86, hotplug: fix llc shared map unreleased during cpu hotplug | From | Toshi Kani <> | Date | Tue, 29 Jul 2014 11:18:15 -0600 |
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On Tue, 2014-07-29 at 17:24 +0800, Wanpeng Li wrote: > BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 > IP: [..] find_busiest_group > PGD 5a9d5067 PUD 13067 PMD 0 > Oops: 0000 [#3] SMP > [...] > Call Trace: > load_balance > ? _raw_spin_unlock_irqrestore > idle_balance > __schedule > schedule > schedule_timeout > ? lock_timer_base > schedule_timeout_uninterruptible > msleep > lock_device_hotplug_sysfs > online_store > dev_attr_store > sysfs_write_file > vfs_write > SyS_write > system_call_fastpath > > Last level cache shared map is built during cpu up and build sched domain > routine takes advantage of it to setup sched domain cpu topology, however, > llc shared map is unreleased during cpu disable which lead to invalid sched > domain cpu topology. This patch fix it by release llc shared map correctly > during cpu disable. > > Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
The change looks good to me.
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
Thanks, -Toshi
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