1. 23 9月, 2010 24 次提交
  2. 22 9月, 2010 13 次提交
  3. 21 9月, 2010 3 次提交
    • S
      sched: Fix nohz balance kick · f6c3f168
      Suresh Siddha 提交于
      There's a situation where the nohz balancer will try to wake itself:
      
      cpu-x is idle which is also ilb_cpu
      got a scheduler tick during idle
      and the nohz_kick_needed() in trigger_load_balance() checks for
      rq_x->nr_running which might not be zero (because of someone waking a
      task on this rq etc) and this leads to the situation of the cpu-x
      sending a kick to itself.
      
      And this can cause a lockup.
      
      Avoid this by not marking ourself eligible for kicking.
      Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      LKML-Reference: <1284400941.2684.19.camel@sbsiddha-MOBL3.sc.intel.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f6c3f168
    • V
      cfq-iosched: fix a kernel OOPs when usb key is inserted · 180be2a0
      Vivek Goyal 提交于
      Mike reported a kernel crash when a usb key hotplug is performed while all
      kernel thrads are not in a root cgroup and are running in one of the child
      cgroups of blkio controller.
      
      	BUG: unable to handle kernel NULL pointer dereference at 0000002c
      	IP: [<c11c7b08>] cfq_get_queue+0x232/0x412
      	*pde = 00000000
      	Oops: 0000 [#1] PREEMPT
      	last sysfs file: /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:1.0/host3/scsi_host/host3/uevent
      
      	[..]
      	Pid: 30039, comm: scsi_scan_3 Not tainted 2.6.35.2-fg.roam #1 Volvi2                         /Aspire 4315
      	EIP: 0060:[<c11c7b08>] EFLAGS: 00010086 CPU: 0
      	EIP is at cfq_get_queue+0x232/0x412
      	EAX: f705f9c0 EBX: e977abac ECX: 00000000 EDX: 00000000
      	ESI: f00da400 EDI: f00da4ec EBP: e977a800 ESP: dff8fd00
      	 DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
      	Process scsi_scan_3 (pid: 30039, ti=dff8e000 task=f6b6c9a0 task.ti=dff8e000)
      	Stack:
      	 00000000 00000000 00000001 01ff0000 f00da508 00000000 f00da524 f00da540
      	<0> e7994940 dd631750 f705f9c0 e977a820 e977ac44 f00da4d0 00000001 f6b6c9a0
      	<0> 00000010 00008010 0000000b 00000000 00000001 e977a800 dd76fac0 00000246
      	Call Trace:
      	 [<c11c7f10>] ? cfq_set_request+0x228/0x34c
      	 [<c11c7ce8>] ? cfq_set_request+0x0/0x34c
      	 [<c11bb3b9>] ? elv_set_request+0xf/0x1c
      	 [<c11bdd51>] ? get_request+0x1ad/0x22f
      	 [<c11bddf2>] ? get_request_wait+0x1f/0x11a
      	 [<c11d013b>] ? kvasprintf+0x33/0x3b
      	 [<c127b537>] ? scsi_execute+0x1d/0x103
      	 [<c127b675>] ? scsi_execute_req+0x58/0x83
      	 [<c127c391>] ? scsi_probe_and_add_lun+0x188/0x7c2
      	 [<c12718c6>] ? attribute_container_add_device+0x15/0xfa
      	 [<c11c95d1>] ? kobject_get+0xf/0x13
      	 [<c126d1db>] ? get_device+0x10/0x14
      	 [<c127be93>] ? scsi_alloc_target+0x217/0x24d
      	 [<c127cbd8>] ? __scsi_scan_target+0x95/0x480
      	 [<c10204eb>] ? dequeue_entity+0x14/0x1fe
      	 [<c1020491>] ? update_curr+0x165/0x1ab
      	 [<c1020491>] ? update_curr+0x165/0x1ab
      	 [<c127d00d>] ? scsi_scan_channel+0x4a/0x76
      	 [<c127d0b0>] ? scsi_scan_host_selected+0x77/0xad
      	 [<c127d13c>] ? do_scan_async+0x0/0x11a
      	 [<c127d137>] ? do_scsi_scan_host+0x51/0x56
      	 [<c127d13c>] ? do_scan_async+0x0/0x11a
      	 [<c127d14a>] ? do_scan_async+0xe/0x11a
      	 [<c127d13c>] ? do_scan_async+0x0/0x11a
      	 [<c10354c5>] ? kthread+0x5e/0x63
      	 [<c1035467>] ? kthread+0x0/0x63
      	 [<c1002af6>] ? kernel_thread_helper+0x6/0x10
      	Code: 44 24 1c 54 83 44 24 18 54 83 fa 03 75 94 8b 06 c7 86 64 02 00 00 01 00 00 00 83 e0 03 09 f0 89 06 8b 44 24 28 8b 90 58 01 00 00 <8b> 42 2c 85 c0 75 03 8b 42 08 8d 54 24 48 52 8d 4c 24 50 51 68
      	EIP: [<c11c7b08>] cfq_get_queue+0x232/0x412 SS:ESP 0068:dff8fd00
      	CR2: 000000000000002c
      	---[ end trace 9a88306573f69b12 ]---
      
      The problem here is that we don't have bdi->dev information available when
      thread does some IO.  Hence when dev_name() tries to access bdi->dev, it
      crashes.
      
      This problem does not happen if kernel threads are in root group as root
      group is statically allocated at device initialization time and we don't
      hit this piece of code.
      
      Fix it by delaying the filling of major and minor number information of
      device in blk_group.  Initially a blk_group is created with 0 as device
      information and this information is filled later once some more IO comes
      in from same group.
      Reported-by: NMike Kazantsev <mk.fraggod@gmail.com>
      Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: NJens Axboe <jaxboe@fusionio.com>
      180be2a0
    • B
      block: fix blk_rq_map_kern bio direction flag · a45dc2d2
      Benny Halevy 提交于
      This bug was introduced in 7b6d91da
      "block: unify flags for struct bio and struct request"
      
      Cc: Boaz Harrosh <bharrosh@panasas.com>
      Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
      Signed-off-by: NJens Axboe <jaxboe@fusionio.com>
      a45dc2d2