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author | Zhang Qiao <zhangqiao22@huawei.com> | 2022-01-21 11:12:10 +0100 |
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committer | Tejun Heo <tj@kernel.org> | 2022-02-14 20:48:04 +0100 |
commit | 05c7b7a92cc87ff8d7fde189d0fade250697573c (patch) | |
tree | ca03eee0d94326ebdd3915f3e0127bbbdc3d4289 /Documentation/networking/cdc_mbim.rst | |
parent | cgroup/cpuset: Fix "suspicious RCU usage" lockdep warning (diff) | |
download | linux-05c7b7a92cc87ff8d7fde189d0fade250697573c.tar.xz linux-05c7b7a92cc87ff8d7fde189d0fade250697573c.zip |
cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug
As previously discussed(https://lkml.org/lkml/2022/1/20/51),
cpuset_attach() is affected with similar cpu hotplug race,
as follow scenario:
cpuset_attach() cpu hotplug
--------------------------- ----------------------
down_write(cpuset_rwsem)
guarantee_online_cpus() // (load cpus_attach)
sched_cpu_deactivate
set_cpu_active()
// will change cpu_active_mask
set_cpus_allowed_ptr(cpus_attach)
__set_cpus_allowed_ptr_locked()
// (if the intersection of cpus_attach and
cpu_active_mask is empty, will return -EINVAL)
up_write(cpuset_rwsem)
To avoid races such as described above, protect cpuset_attach() call
with cpu_hotplug_lock.
Fixes: be367d099270 ("cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time")
Cc: stable@vger.kernel.org # v2.6.32+
Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
Signed-off-by: Zhang Qiao <zhangqiao22@huawei.com>
Acked-by: Waiman Long <longman@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'Documentation/networking/cdc_mbim.rst')
0 files changed, 0 insertions, 0 deletions