[hyperv] BUG: unable to handle kernel paging request at ffff8801f5bc7cbb (netvsc_select_queue)

From: Sitsofe Wheeler
Date: Fri Aug 29 2014 - 05:31:53 EST


While booting a 10 vcpu system with a post v3.17-rc2 kernel with the
"Drivers: hv: vmbus: Eliminate calls to BUG_ON()", "Drivers: hv: vmbus:
Miscellaneous cleanup" patches and debugging/verification config options
on I'm seeing the following:

[ 31.570860] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null)
[ 31.799558] systemd-journald[367]: Received request to flush runtime journal from PID 1
[ 32.679811] hv_utils: KVP: user-mode registering done.
[ 39.826001] hv_netvsc vmbus_0_15: net device safe to remove
[ 39.868109] hv_netvsc: hv_netvsc channel opened successfully
[ 41.585834] hv_netvsc vmbus_0_15: Send section size: 6144, Section count:2560
[ 41.644187] hv_netvsc vmbus_0_15: Device MAC 00:15:5d:6f:02:a5 link state up
[ 43.174058] BUG: unable to handle kernel paging request at ffff8801f5bc7cbb
[ 43.174956] IP: [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 43.174956] PGD 2db0067 PUD 207dc0067 PMD 207c12067 PTE 80000001f5bc7060
[ 43.174956] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 43.174956] CPU: 7 PID: 640 Comm: arping Not tainted 3.17.0-rc2.x86_64-00096-g9c6196f #137
[ 43.174956] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012
[ 43.174956] task: ffff8800ebc56090 ti: ffff8800ecf04000 task.ti: ffff8800ecf04000
[ 43.174956] RIP: 0010:[<ffffffff814e701d>] [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 43.174956] RSP: 0018:ffff8800ecf07c60 EFLAGS: 00010206
[ 43.174956] RAX: 0000000000000000 RBX: ffff8800f13f0000 RCX: 000000000000ffff
[ 43.174956] RDX: ffff8801f5bb7cb0 RSI: ffff8800ecf47a80 RDI: ffff8800f13f0000
[ 43.174956] RBP: ffff8800ecf07c88 R08: 000000000000002a R09: 0000000000000000
[ 43.174956] R10: ffff8801f99b2290 R11: 000000000000000a R12: ffff8800ecf47a80
[ 43.174956] R13: 0000000000000000 R14: ffff8800ecfb1bd8 R15: ffff8800ecf47a80
[ 43.174956] FS: 00007f69fdf31740(0000) GS:ffff880206ce0000(0000) knlGS:0000000000000000
[ 43.174956] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 43.174956] CR2: ffff8801f5bc7cbb CR3: 00000000ecfc9000 CR4: 00000000000406e0
[ 43.174956] Stack:
[ 43.174956] ffffffff8167f651 ffff8800f13f0000 000000000000001c 0000000000000000
[ 43.174956] ffff8800ecfb1bd8 ffff8800ecf07d48 ffffffff816833bc ffff8800ebc567d0
[ 43.174956] 0000000000000000 ffff8800ecf07d68 0000000000000046 000000000000001c
[ 43.174956] Call Trace:
[ 43.174956] [<ffffffff8167f651>] ? packet_pick_tx_queue+0x31/0xa0
[ 43.174956] [<ffffffff816833bc>] packet_sendmsg+0xc1c/0xdd0
[ 43.174956] [<ffffffff810bd106>] ? lock_release_non_nested+0xc6/0x330
[ 43.174956] [<ffffffff815b4368>] sock_sendmsg+0x88/0xb0
[ 43.174956] [<ffffffff81185443>] ? might_fault+0xa3/0xb0
[ 43.174956] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 43.174956] [<ffffffff815b449e>] SYSC_sendto+0x10e/0x150
[ 43.174956] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 43.174956] [<ffffffff816a32d5>] ? sysret_check+0x22/0x5d
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff8139c09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 43.174956] [<ffffffff815b547e>] SyS_sendto+0xe/0x10
[ 43.174956] [<ffffffff816a32a9>] system_call_fastpath+0x16/0x1b
[ 43.174956] Code: 00 4d 85 d2 0f 84 1c 01 00 00 44 8b 9f 8c 03 00 00 31 c0 41 83 fb 01 0f 86 1b 01 00 00 0f b7 8e b4 00 00 00 48 8b 96 c0 00 00 00 <66> 83 7c 0a 0c 08 0f 85 01 01 00 00 55 48 89 e5 41 55 41 54 53
[ 43.174956] RIP [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 43.174956] RSP <ffff8800ecf07c60>
[ 43.174956] CR2: ffff8801f5bc7cbb
[ 43.174956] ---[ end trace d476efa8244dbdc1 ]---
[ 43.174956] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:41
[ 43.174956] in_atomic(): 0, irqs_disabled(): 1, pid: 640, name: arping
[ 43.174956] INFO: lockdep is turned off.
[ 43.174956] irq event stamp: 5710
[ 43.174956] hardirqs last enabled at (5709): [<ffffffff81698cb4>] __slab_alloc+0x50b/0x576
[ 43.174956] hardirqs last disabled at (5710): [<ffffffff816a5326>] error_sti+0x5/0x6
[ 43.174956] softirqs last enabled at (5662): [<ffffffff815cedb0>] __dev_queue_xmit+0x5b0/0x690
[ 43.174956] softirqs last disabled at (5628): [<ffffffff815ce858>] __dev_queue_xmit+0x58/0x690
[ 43.174956] CPU: 7 PID: 640 Comm: arping Tainted: G D 3.17.0-rc2.x86_64-00096-g9c6196f #137
[ 43.174956] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012
[ 43.174956] 0000000000000046 ffff8800ecf078e0 ffffffff8169a70b ffff8800ebc56090
[ 43.174956] ffff8800ecf078f8 ffffffff8109ec65 ffff8801f35eacd8 ffff8800ecf07918
[ 43.174956] ffffffff816a0d44 ffffffff81090f38 ffff8800ebc56090 ffff8800ecf07938
[ 43.174956] Call Trace:
[ 43.174956] [<ffffffff8169a70b>] dump_stack+0x4d/0x66
[ 43.174956] [<ffffffff8109ec65>] __might_sleep+0x115/0x120
[ 43.174956] [<ffffffff816a0d44>] down_read+0x24/0x70
[ 43.174956] [<ffffffff81090f38>] ? __validate_process_creds+0xd8/0xf0
[ 43.174956] [<ffffffff8107f9d4>] exit_signals+0x24/0x140
[ 43.174956] [<ffffffff810737d9>] do_exit+0x129/0xa20
[ 43.174956] [<ffffffff810c4bcc>] ? kmsg_dump+0xfc/0x110
[ 43.174956] [<ffffffff810c4af5>] ? kmsg_dump+0x25/0x110
[ 43.174956] [<ffffffff81006348>] oops_end+0xa8/0xc0
[ 43.174956] [<ffffffff81695288>] no_context+0x322/0x36b
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff8169549c>] __bad_area_nosemaphore+0x1cb/0x1e8
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff816954cc>] bad_area_nosemaphore+0x13/0x15
[ 43.174956] [<ffffffff8104040e>] __do_page_fault+0x1ee/0x4f0
[ 43.174956] [<ffffffff815bcd6e>] ? __alloc_skb+0x4e/0x240
[ 43.174956] [<ffffffff810bd106>] ? lock_release_non_nested+0xc6/0x330
[ 43.174956] [<ffffffff8139c0dd>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[ 43.174956] [<ffffffff81040762>] do_page_fault+0x22/0x30
[ 43.174956] [<ffffffff816a5108>] page_fault+0x28/0x30
[ 43.174956] [<ffffffff814e701d>] ? netvsc_select_queue+0x3d/0x150
[ 43.174956] [<ffffffff8167f651>] ? packet_pick_tx_queue+0x31/0xa0
[ 43.174956] [<ffffffff816833bc>] packet_sendmsg+0xc1c/0xdd0
[ 43.174956] [<ffffffff810bd106>] ? lock_release_non_nested+0xc6/0x330
[ 43.174956] [<ffffffff815b4368>] sock_sendmsg+0x88/0xb0
[ 43.174956] [<ffffffff81185443>] ? might_fault+0xa3/0xb0
[ 43.174956] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 43.174956] [<ffffffff815b449e>] SYSC_sendto+0x10e/0x150
[ 43.174956] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 43.174956] [<ffffffff816a32d5>] ? sysret_check+0x22/0x5d
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff8139c09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 43.174956] [<ffffffff815b547e>] SyS_sendto+0xe/0x10
[ 43.174956] [<ffffffff816a32a9>] system_call_fastpath+0x16/0x1b
[ 43.174956] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:41
[ 43.174956] in_atomic(): 0, irqs_disabled(): 1, pid: 640, name: arping
[ 43.174956] INFO: lockdep is turned off.
[ 43.174956] irq event stamp: 5710
[ 43.174956] hardirqs last enabled at (5709): [<ffffffff81698cb4>] __slab_alloc+0x50b/0x576
[ 43.174956] hardirqs last disabled at (5710): [<ffffffff816a5326>] error_sti+0x5/0x6
[ 43.174956] softirqs last enabled at (5662): [<ffffffff815cedb0>] __dev_queue_xmit+0x5b0/0x690
[ 43.174956] softirqs last disabled at (5628): [<ffffffff815ce858>] __dev_queue_xmit+0x58/0x690
[ 43.174956] CPU: 7 PID: 640 Comm: arping Tainted: G D 3.17.0-rc2.x86_64-00096-g9c6196f #137
[ 43.174956] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012
[ 43.174956] ffff8800ebc56090 ffff8800ecf078d0 ffffffff8169a70b ffff8800ebc56090
[ 43.174956] ffff8800ecf078e8 ffffffff8109ec65 ffff8801f3afba18 ffff8800ecf07908
[ 43.174956] ffffffff816a0d44 ffffffff810d5cb1 ffff8801f35ea880 ffff8800ecf07938
[ 43.174956] Call Trace:
[ 43.174956] [<ffffffff8169a70b>] dump_stack+0x4d/0x66
[ 43.174956] [<ffffffff8109ec65>] __might_sleep+0x115/0x120
[ 43.174956] [<ffffffff816a0d44>] down_read+0x24/0x70
[ 43.174956] [<ffffffff810d5cb1>] ? hrtimer_try_to_cancel+0xf1/0x100
[ 43.174956] [<ffffffff810ec612>] acct_collect+0x52/0x1c0
[ 43.174956] [<ffffffff81074082>] do_exit+0x9d2/0xa20
[ 43.174956] [<ffffffff810c4bcc>] ? kmsg_dump+0xfc/0x110
[ 43.174956] [<ffffffff810c4af5>] ? kmsg_dump+0x25/0x110
[ 43.174956] [<ffffffff81006348>] oops_end+0xa8/0xc0
[ 43.174956] [<ffffffff81695288>] no_context+0x322/0x36b
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff8169549c>] __bad_area_nosemaphore+0x1cb/0x1e8
[ 43.174956] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 43.174956] [<ffffffff816954cc>] bad_area_nosemaphore+0x13/0x15
[ 43.174956] [<ffffffff8104040e>] __do_page_fault+0x1ee/0x4f0
[ 43.174956] [<ffffffff815bcd6e>] ? __alloc_skb+0x4e/0x240
[ 43.174956] [<ffffffff810bd106>] ? lock_release_non_nested+0xc6/0x330
[ 43.174956] [<ffffffff8139c0dd>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[ 43.174956] [<ffffffff81040762>] do_page_fault+0x22/0x30
[ 43.174956] [<ffffffff816a5108>] page_fault+0x28/0x30
[ 43.174956] [<ffffffff814e701d>] ? netvsc_select_queue+0x3d/0x150
[ 43.174956] [<ffffffff8167f651>] ? packet_pick_tx_queue+0x31/0xa0
[ 43.174956] [<ffffffff816833bc>] packet_sendmsg+0xc1c/0xdd0
[ 43.174956] [<ffffffff810bd106>] ? lock_release_non_nested+0xc6/0x330
[ 43.174956] [<ffffffff815b4368>] sock_sendmsg+0x88/0xb0
[ 43.174956] [<ffffffff81185443>] ? might_fault+0xa3/0xb0
[ 43.174956] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 48.347217] [<ffffffff815b449e>] SYSC_sendto+0x10e/0x150
[ 48.347217] [<ffffffff811853fa>] ? might_fault+0x5a/0xb0
[ 48.347217] [<ffffffff816a32d5>] ? sysret_check+0x22/0x5d
[ 48.347217] [<ffffffff810b97fd>] ? trace_hardirqs_on_caller+0x17d/0x210
[ 48.347217] [<ffffffff8139c09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 48.347217] [<ffffffff815b547e>] SyS_sendto+0xe/0x10
[ 48.347217] [<ffffffff816a32a9>] system_call_fastpath+0x16/0x1b
[ 48.663676] BUG: unable to handle kernel paging request at ffff8800ee453a23
[ 48.708188] IP:
[ 48.708188] [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 48.708188] PGD 2db0067
[ 48.708188] PUD 2075be067
[ 48.708188] PMD 20744b067
[ 48.708188] PTE 80000000ee453060

[ 48.708188] Oops: 0000 [#2]
[ 48.708188] SMP
[ 48.708188] DEBUG_PAGEALLOC

[ 48.708188] CPU: 7 PID: 609 Comm: dhclient Tainted: G D 3.17.0-rc2.x86_64-00096-g9c6196f #137
[ 48.708188] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012
[ 48.708188] task: ffff8801f9946090 ti: ffff8800ee468000 task.ti: ffff8800ee468000
[ 48.708188] RIP: 0010:[<ffffffff814e701d>]
[ 48.708188] [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 48.708188] RSP: 0018:ffff8800ee46bcd8 EFLAGS: 00010206
[ 48.708188] RAX: 0000000000000000 RBX: ffff8800f13f0000 RCX: 000000000000ffff
[ 48.708188] RDX: ffff8800ee443a18 RSI: ffff8800ecf446c0 RDI: ffff8800f13f0000
[ 48.708188] RBP: ffff8800ee46bd00 R08: 0000000000000156 R09: 0000000000000000
[ 48.708188] R10: ffff8801f99b2290 R11: 000000000000000a R12: ffff8800ecf446c0
[ 48.708188] R13: 0000000000000000 R14: ffff8800ecfb0948 R15: ffff8800ecf446c0
[ 48.708188] FS: 00007f5b90b22880(0000) GS:ffff880206ce0000(0000) knlGS:0000000000000000
[ 48.708188] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 48.708188] CR2: ffff8800ee453a23 CR3: 00000000ec783000 CR4: 00000000000406e0
[ 48.708188] Stack:
[ 48.708188] ffffffff8167f651
[ 48.708188] ffff8800f13f0000
[ 48.708188] 0000000000000156
[ 48.708188] 0000000000000000

[ 48.708188] ffff8800ecfb0948
[ 48.708188] ffff8800ee46bdc0
[ 48.708188] ffffffff816833bc
[ 48.708188] ffffffff00000000

[ 48.708188] 00000000ffffffff
[ 48.708188] ffff8800ee46bd58
[ 48.708188] ffff8800f3354440
[ 48.708188] 0000000000000156

[ 48.708188] Call Trace:

[ 48.708188] [<ffffffff8167f651>] ? packet_pick_tx_queue+0x31/0xa0
[ 48.708188] [<ffffffff816833bc>] packet_sendmsg+0xc1c/0xdd0
[ 48.708188] [<ffffffff815b357b>] sock_aio_write+0xfb/0x120
[ 48.708188] [<ffffffff811c262a>] do_sync_write+0x5a/0x80
[ 48.708188] [<ffffffff811c2925>] vfs_write+0xe5/0x1d0
[ 48.708188] [<ffffffff811c2b09>] SyS_write+0x49/0xb0
[ 48.708188] [<ffffffff816a32a9>] system_call_fastpath+0x16/0x1b
[ 48.708188] Code: 00 4d 85 d2 0f 84 1c 01 00 00 44 8b 9f 8c 03 00 00 31 c0 41 83 fb 01 0f 86 1b 01 00 00 0f b7 8e b4 00 00 00 48 8b 96 c0 00 00 00 <66> 83 7c 0a 0c 08 0f 85 01 01 00 00 55 48 89 e5 41 55 41 54 53
[ 48.708188] RIP [<ffffffff814e701d>] netvsc_select_queue+0x3d/0x150
[ 48.708188] RSP <ffff8800ee46bcd8>
[ 48.708188] CR2: ffff8800ee453a23
[ 48.708188] ---[ end trace d476efa8244dbdc2 ]---
[ 48.708188] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:41
[ 48.708188] in_atomic(): 0, irqs_disabled(): 1, pid: 609, name: dhclient
[ 48.708188] INFO: lockdep is turned off.
[ 48.708188] irq event stamp: 97752
[ 48.708188] hardirqs last enabled at (97751): [<ffffffff816a263d>] _raw_spin_unlock_irqrestore+0x4d/0x70
[ 48.708188] hardirqs last disabled at (97752): [<ffffffff816a251d>] _raw_spin_lock_irq+0x1d/0x60
[ 48.708188] softirqs last enabled at (97356): [<ffffffff810753f8>] __do_softirq+0x278/0x320
[ 48.708188] softirqs last disabled at (97341): [<ffffffff81075768>] irq_exit+0x58/0xc0
[ 48.708188] CPU: 7 PID: 609 Comm: dhclient Tainted: G D 3.17.0-rc2.x86_64-00096-g9c6196f #137
[ 48.708188] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006 05/23/2012
[ 48.708188] 0000000000000046 ffff8800ee46b950 ffffffff8169a70b ffff8801f9946090
[ 48.708188] ffff8800ee46b968 ffffffff8109ec65 ffff8801f35e9898 ffff8800ee46b988
[ 48.708188] ffffffff816a0d44 ffffffff81090f38 ffff8801f9946090 ffff8800ee46b9a8
[ 48.708188] Call Trace:
[ 48.708188] [<ffffffff8169a70b>] dump_stack+0x4d/0x66
[ 48.708188] [<ffffffff8109ec65>] __might_sleep+0x115/0x120
[ 48.708188] [<ffffffff816a0d44>] down_read+0x24/0x70
[ 48.708188] [<ffffffff81090f38>] ? __validate_process_creds+0xd8/0xf0
[ 48.708188] [<ffffffff8107f9d4>] exit_signals+0x24/0x140
[ 48.708188] [<ffffffff810737d9>] do_exit+0x129/0xa20
[ 48.708188] [<ffffffff810c4bcc>] ? kmsg_dump+0xfc/0x110
[ 48.708188] [<ffffffff810c4af5>] ? kmsg_dump+0x25/0x110
[ 48.708188] [<ffffffff81006348>] oops_end+0xa8/0xc0
[ 48.708188] [<ffffffff81695288>] no_context+0x322/0x36b
[ 48.708188] [<ffffffff8169549c>] __bad_area_nosemaphore+0x1cb/0x1e8
[ 48.708188] [<ffffffff816954cc>] bad_area_nosemaphore+0x13/0x15
[ 48.708188] [<ffffffff8104040e>] __do_page_fault+0x1ee/0x4f0
[ 48.708188] [<ffffffff815bcd6e>] ? __alloc_skb+0x4e/0x240
[ 48.708188] [<ffffffff811a990e>] ? __kmalloc_node_track_caller+0x15e/0x2f0
[ 48.708188] [<ffffffff810b9b0d>] ? trace_hardirqs_off+0xd/0x10
[ 48.708188] [<ffffffff8139c0dd>] ? trace_hardirqs_off_thunk+0x3a/0x3c
[ 48.708188] [<ffffffff81040762>] do_page_fault+0x22/0x30
[ 48.708188] [<ffffffff816a5108>] page_fault+0x28/0x30
[ 48.708188] [<ffffffff814e701d>] ? netvsc_select_queue+0x3d/0x150
[ 48.708188] [<ffffffff8167f651>] ? packet_pick_tx_queue+0x31/0xa0
[ 48.708188] [<ffffffff816833bc>] packet_sendmsg+0xc1c/0xdd0
[ 48.708188] [<ffffffff815b357b>] sock_aio_write+0xfb/0x120
[ 48.708188] [<ffffffff811c262a>] do_sync_write+0x5a/0x80
[ 48.708188] [<ffffffff811c2925>] vfs_write+0xe5/0x1d0
[ 48.708188] [<ffffffff811c2b09>] SyS_write+0x49/0xb0
[ 48.708188] [<ffffffff816a32a9>] system_call_fastpath+0x16/0x1b

In https://lkml.org/lkml/2014/8/19/133 (Re: BUG: unable to handle kernel
paging request at ffff8801f3febe63 (netvsc_select_queue)) there is the
following:

On Tue, Aug 19, 2014 at 10:57:30AM +0200, Daniel Borkmann wrote:
>
> Hmm, I am not really familiar with hyper-v, but it seems 5b54dac856cb
> ("hyperv: Add support for virtual Receive Side Scaling (vRSS)") has
> been introduced after 0fd5d57ba345 ("packet: check for
> ndo_select_queue during queue selection").
>
> arping seems to send a raw packet (AF_PACKET) via normal
> packet_sendmsg() out and when doing the queue selection in
> packet_pick_tx_queue(), we discover that the device has
> ndo_select_queue implemented, so we respect that and call into it. In
> netvsc_select_queue(), the fallback of __packet_pick_tx_queue() is not
> being invoked here.
>
> Given that the next log message is "hv_netvsc vmbus_0_15: net device
> safe to remove" ... could it be that your back pointer to the device
> context (the actual struct hv_device) is already invalid when you try
> to get hv_get_drvdata(hdev) as it's sort of decoupled from
> netdev_priv(ndev) ? (Just a wild guess ...)

So I'm guessing this is the same issue.

--
Sitsofe | http://sucs.org/~sits/
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