| Message ID | 1383030667-14343-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, Oct 29, 2013 at 03:11:07PM +0800, Jason Wang wrote: > commit 3ab098df35f8b98b6553edc2e40234af512ba877 (virtio-net: don't respond to > cpu hotplug notifier if we're not ready) tries to bypass the cpu hotplug > notifier by checking the config_enable and does nothing is it was false. So it > need to try to hold the config_lock mutex which may happen in atomic > environment which leads the following warnings: > > [ 622.944441] CPU0 attaching NULL sched-domain. > [ 622.944446] CPU1 attaching NULL sched-domain. > [ 622.944485] CPU0 attaching NULL sched-domain. > [ 622.950795] BUG: sleeping function called from invalid context at kernel/mutex.c:616 > [ 622.950796] in_atomic(): 1, irqs_disabled(): 1, pid: 10, name: migration/1 > [ 622.950796] no locks held by migration/1/10. > [ 622.950798] CPU: 1 PID: 10 Comm: migration/1 Not tainted 3.12.0-rc5-wl-01249-gb91e82d #317 > [ 622.950799] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 622.950802] 0000000000000000 ffff88001d42dba0 ffffffff81a32f22 ffff88001bfb9c70 > [ 622.950803] ffff88001d42dbb0 ffffffff810edb02 ffff88001d42dc38 ffffffff81a396ed > [ 622.950805] 0000000000000046 ffff88001d42dbe8 ffffffff810e861d 0000000000000000 > [ 622.950805] Call Trace: > [ 622.950810] [<ffffffff81a32f22>] dump_stack+0x54/0x74 > [ 622.950815] [<ffffffff810edb02>] __might_sleep+0x112/0x114 > [ 622.950817] [<ffffffff81a396ed>] mutex_lock_nested+0x3c/0x3c6 > [ 622.950818] [<ffffffff810e861d>] ? up+0x39/0x3e > [ 622.950821] [<ffffffff8153ea7c>] ? acpi_os_signal_semaphore+0x21/0x2d > [ 622.950824] [<ffffffff81565ed1>] ? acpi_ut_release_mutex+0x5e/0x62 > [ 622.950828] [<ffffffff816d04ec>] virtnet_cpu_callback+0x33/0x87 > [ 622.950830] [<ffffffff81a42576>] notifier_call_chain+0x3c/0x5e > [ 622.950832] [<ffffffff810e86a8>] __raw_notifier_call_chain+0xe/0x10 > [ 622.950835] [<ffffffff810c5556>] __cpu_notify+0x20/0x37 > [ 622.950836] [<ffffffff810c5580>] cpu_notify+0x13/0x15 > [ 622.950838] [<ffffffff81a237cd>] take_cpu_down+0x27/0x3a > [ 622.950841] [<ffffffff81136289>] stop_machine_cpu_stop+0x93/0xf1 > [ 622.950842] [<ffffffff81136167>] cpu_stopper_thread+0xa0/0x12f > [ 622.950844] [<ffffffff811361f6>] ? cpu_stopper_thread+0x12f/0x12f > [ 622.950847] [<ffffffff81119710>] ? lock_release_holdtime.part.7+0xa3/0xa8 > [ 622.950848] [<ffffffff81135e4b>] ? cpu_stop_should_run+0x3f/0x47 > [ 622.950850] [<ffffffff810ea9b0>] smpboot_thread_fn+0x1c5/0x1e3 > [ 622.950852] [<ffffffff810ea7eb>] ? lg_global_unlock+0x67/0x67 > [ 622.950854] [<ffffffff810e36b7>] kthread+0xd8/0xe0 > [ 622.950857] [<ffffffff81a3bfad>] ? wait_for_common+0x12f/0x164 > [ 622.950859] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 > [ 622.950861] [<ffffffff81a45ffc>] ret_from_fork+0x7c/0xb0 > [ 622.950862] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 > [ 622.950876] smpboot: CPU 1 is now offline > [ 623.194556] SMP alternatives: lockdep: fixing up alternatives > [ 623.194559] smpboot: Booting Node 0 Processor 1 APIC 0x1 > ... > > A correct fix is to unregister the hotcpu notifier during restore and register a > new one in resume. > > Reported-by: Fengguang Wu <fengguang.wu@intel.com> > Tested-by: Fengguang Wu <fengguang.wu@intel.com> > Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com> > Cc: Rusty Russell <rusty@rustcorp.com.au> > Cc: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> BTW there's a new Fixes: tag, you might want to use it in the future. > --- > This patch is needed for 3.8 and above. > --- > drivers/net/virtio_net.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 9fbdfcd..bbc9cb8 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1118,11 +1118,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, > { > struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb); > > - mutex_lock(&vi->config_lock); > - > - if (!vi->config_enable) > - goto done; > - > switch(action & ~CPU_TASKS_FROZEN) { > case CPU_ONLINE: > case CPU_DOWN_FAILED: > @@ -1136,8 +1131,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, > break; > } > > -done: > - mutex_unlock(&vi->config_lock); > return NOTIFY_OK; > } > > @@ -1699,6 +1692,8 @@ static int virtnet_freeze(struct virtio_device *vdev) > struct virtnet_info *vi = vdev->priv; > int i; > > + unregister_hotcpu_notifier(&vi->nb); > + > /* Prevent config work handler from accessing the device */ > mutex_lock(&vi->config_lock); > vi->config_enable = false; > @@ -1747,6 +1742,10 @@ static int virtnet_restore(struct virtio_device *vdev) > virtnet_set_queues(vi, vi->curr_queue_pairs); > rtnl_unlock(); > > + err = register_hotcpu_notifier(&vi->nb); > + if (err) > + return err; > + > return 0; > } > #endif > -- > 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 10/29/2013 03:11 PM, Jason Wang wrote: > commit 3ab098df35f8b98b6553edc2e40234af512ba877 (virtio-net: don't respond to > cpu hotplug notifier if we're not ready) tries to bypass the cpu hotplug > notifier by checking the config_enable and does nothing is it was false. So it > need to try to hold the config_lock mutex which may happen in atomic > environment which leads the following warnings: > > [ 622.944441] CPU0 attaching NULL sched-domain. > [ 622.944446] CPU1 attaching NULL sched-domain. > [ 622.944485] CPU0 attaching NULL sched-domain. > [ 622.950795] BUG: sleeping function called from invalid context at kernel/mutex.c:616 > [ 622.950796] in_atomic(): 1, irqs_disabled(): 1, pid: 10, name: migration/1 > [ 622.950796] no locks held by migration/1/10. > [ 622.950798] CPU: 1 PID: 10 Comm: migration/1 Not tainted 3.12.0-rc5-wl-01249-gb91e82d #317 > [ 622.950799] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 622.950802] 0000000000000000 ffff88001d42dba0 ffffffff81a32f22 ffff88001bfb9c70 > [ 622.950803] ffff88001d42dbb0 ffffffff810edb02 ffff88001d42dc38 ffffffff81a396ed > [ 622.950805] 0000000000000046 ffff88001d42dbe8 ffffffff810e861d 0000000000000000 > [ 622.950805] Call Trace: > [ 622.950810] [<ffffffff81a32f22>] dump_stack+0x54/0x74 > [ 622.950815] [<ffffffff810edb02>] __might_sleep+0x112/0x114 > [ 622.950817] [<ffffffff81a396ed>] mutex_lock_nested+0x3c/0x3c6 > [ 622.950818] [<ffffffff810e861d>] ? up+0x39/0x3e > [ 622.950821] [<ffffffff8153ea7c>] ? acpi_os_signal_semaphore+0x21/0x2d > [ 622.950824] [<ffffffff81565ed1>] ? acpi_ut_release_mutex+0x5e/0x62 > [ 622.950828] [<ffffffff816d04ec>] virtnet_cpu_callback+0x33/0x87 > [ 622.950830] [<ffffffff81a42576>] notifier_call_chain+0x3c/0x5e > [ 622.950832] [<ffffffff810e86a8>] __raw_notifier_call_chain+0xe/0x10 > [ 622.950835] [<ffffffff810c5556>] __cpu_notify+0x20/0x37 > [ 622.950836] [<ffffffff810c5580>] cpu_notify+0x13/0x15 > [ 622.950838] [<ffffffff81a237cd>] take_cpu_down+0x27/0x3a > [ 622.950841] [<ffffffff81136289>] stop_machine_cpu_stop+0x93/0xf1 > [ 622.950842] [<ffffffff81136167>] cpu_stopper_thread+0xa0/0x12f > [ 622.950844] [<ffffffff811361f6>] ? cpu_stopper_thread+0x12f/0x12f > [ 622.950847] [<ffffffff81119710>] ? lock_release_holdtime.part.7+0xa3/0xa8 > [ 622.950848] [<ffffffff81135e4b>] ? cpu_stop_should_run+0x3f/0x47 > [ 622.950850] [<ffffffff810ea9b0>] smpboot_thread_fn+0x1c5/0x1e3 > [ 622.950852] [<ffffffff810ea7eb>] ? lg_global_unlock+0x67/0x67 > [ 622.950854] [<ffffffff810e36b7>] kthread+0xd8/0xe0 > [ 622.950857] [<ffffffff81a3bfad>] ? wait_for_common+0x12f/0x164 > [ 622.950859] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 > [ 622.950861] [<ffffffff81a45ffc>] ret_from_fork+0x7c/0xb0 > [ 622.950862] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 > [ 622.950876] smpboot: CPU 1 is now offline > [ 623.194556] SMP alternatives: lockdep: fixing up alternatives > [ 623.194559] smpboot: Booting Node 0 Processor 1 APIC 0x1 > ... > > A correct fix is to unregister the hotcpu notifier during restore and register a > new one in resume. > > Reported-by: Fengguang Wu <fengguang.wu@intel.com> > Tested-by: Fengguang Wu <fengguang.wu@intel.com> > Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com> > Cc: Rusty Russell <rusty@rustcorp.com.au> > Cc: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> Thank you for your fix. Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> > --- > This patch is needed for 3.8 and above. > --- > drivers/net/virtio_net.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 9fbdfcd..bbc9cb8 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1118,11 +1118,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, > { > struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb); > > - mutex_lock(&vi->config_lock); > - > - if (!vi->config_enable) > - goto done; > - > switch(action & ~CPU_TASKS_FROZEN) { > case CPU_ONLINE: > case CPU_DOWN_FAILED: > @@ -1136,8 +1131,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, > break; > } > > -done: > - mutex_unlock(&vi->config_lock); > return NOTIFY_OK; > } > > @@ -1699,6 +1692,8 @@ static int virtnet_freeze(struct virtio_device *vdev) > struct virtnet_info *vi = vdev->priv; > int i; > > + unregister_hotcpu_notifier(&vi->nb); > + > /* Prevent config work handler from accessing the device */ > mutex_lock(&vi->config_lock); > vi->config_enable = false; > @@ -1747,6 +1742,10 @@ static int virtnet_restore(struct virtio_device *vdev) > virtnet_set_queues(vi, vi->curr_queue_pairs); > rtnl_unlock(); > > + err = register_hotcpu_notifier(&vi->nb); > + if (err) > + return err; > + > return 0; > } > #endif > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Jason Wang <jasowang@redhat.com> Date: Tue, 29 Oct 2013 15:11:07 +0800 > commit 3ab098df35f8b98b6553edc2e40234af512ba877 (virtio-net: don't respond to > cpu hotplug notifier if we're not ready) tries to bypass the cpu hotplug > notifier by checking the config_enable and does nothing is it was false. So it > need to try to hold the config_lock mutex which may happen in atomic > environment which leads the following warnings: ... > A correct fix is to unregister the hotcpu notifier during restore and register a > new one in resume. > > Reported-by: Fengguang Wu <fengguang.wu@intel.com> > Tested-by: Fengguang Wu <fengguang.wu@intel.com> > Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com> > Cc: Rusty Russell <rusty@rustcorp.com.au> > Cc: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > This patch is needed for 3.8 and above. Applied and queued up for -stable, thanks Jason. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 9fbdfcd..bbc9cb8 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1118,11 +1118,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, { struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb); - mutex_lock(&vi->config_lock); - - if (!vi->config_enable) - goto done; - switch(action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: case CPU_DOWN_FAILED: @@ -1136,8 +1131,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb, break; } -done: - mutex_unlock(&vi->config_lock); return NOTIFY_OK; } @@ -1699,6 +1692,8 @@ static int virtnet_freeze(struct virtio_device *vdev) struct virtnet_info *vi = vdev->priv; int i; + unregister_hotcpu_notifier(&vi->nb); + /* Prevent config work handler from accessing the device */ mutex_lock(&vi->config_lock); vi->config_enable = false; @@ -1747,6 +1742,10 @@ static int virtnet_restore(struct virtio_device *vdev) virtnet_set_queues(vi, vi->curr_queue_pairs); rtnl_unlock(); + err = register_hotcpu_notifier(&vi->nb); + if (err) + return err; + return 0; } #endif