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    mm/page_alloc.c: fix build_all_zonelist() where percpu_alloc() is wrongly... · e9959f0f
    KAMEZAWA Hiroyuki 提交于
    mm/page_alloc.c: fix build_all_zonelist() where percpu_alloc() is wrongly called under stop_machine_run()
    
    During memory hotplug, build_allzonelists() may be called under
    stop_machine_run().  In this function, setup_zone_pageset() is called.
    But it's bug because it will do page allocation under stop_machine_run().
    
    Here is a report from Alok Kataria.
    
      BUG: sleeping function called from invalid context at kernel/mutex.c:94
      in_atomic(): 0, irqs_disabled(): 1, pid: 4, name: migration/0
      Pid: 4, comm: migration/0 Not tainted 2.6.35.6-45.fc14.x86_64 #1
      Call Trace:
       [<ffffffff8103d12b>] __might_sleep+0xeb/0xf0
       [<ffffffff81468245>] mutex_lock+0x24/0x50
       [<ffffffff8110eaa6>] pcpu_alloc+0x6d/0x7ee
       [<ffffffff81048888>] ? load_balance+0xbe/0x60e
       [<ffffffff8103a1b3>] ? rt_se_boosted+0x21/0x2f
       [<ffffffff8103e1cf>] ? dequeue_rt_stack+0x18b/0x1ed
       [<ffffffff8110f237>] __alloc_percpu+0x10/0x12
       [<ffffffff81465e22>] setup_zone_pageset+0x38/0xbe
       [<ffffffff810d6d81>] ? build_zonelists_node.clone.58+0x79/0x8c
       [<ffffffff81452539>] __build_all_zonelists+0x419/0x46c
       [<ffffffff8108ef01>] ? cpu_stopper_thread+0xb2/0x198
       [<ffffffff8108f075>] stop_machine_cpu_stop+0x8e/0xc5
       [<ffffffff8108efe7>] ? stop_machine_cpu_stop+0x0/0xc5
       [<ffffffff8108ef57>] cpu_stopper_thread+0x108/0x198
       [<ffffffff81467a37>] ? schedule+0x5b2/0x5cc
       [<ffffffff8108ee4f>] ? cpu_stopper_thread+0x0/0x198
       [<ffffffff81065f29>] kthread+0x7f/0x87
       [<ffffffff8100aae4>] kernel_thread_helper+0x4/0x10
       [<ffffffff81065eaa>] ? kthread+0x0/0x87
       [<ffffffff8100aae0>] ? kernel_thread_helper+0x0/0x10
      Built 5 zonelists in Node order, mobility grouping on.  Total pages: 289456
      Policy zone: Normal
    
    This patch tries to fix the issue by moving setup_zone_pageset() out from
    stop_machine_run(). It's obviously not necessary to be called under
    stop_machine_run().
    
    [akpm@linux-foundation.org: remove unneeded local]
    Reported-by: NAlok Kataria <akataria@vmware.com>
    Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Petr Vandrovec <petr@vmware.com>
    Cc: Pekka Enberg <penberg@cs.helsinki.fi>
    Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
    Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
    e9959f0f
page_alloc.c 152.3 KB