RE: [PATCH v3] igb: Free IRQs when device is hotplugged

[Brown, Aaron F]

> From: netdev-owner@xxxxxxxxxxxxxxx [mailto:netdev-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Lyude Paul
> Sent: Tuesday, December 12, 2017 11:32 AM
> To: intel-wired-lan@xxxxxxxxxxxxxxxx
> Cc: Fujinaka, Todd <todd.fujinaka@xxxxxxxxx>; Stephen Hemminger
> <stephen@xxxxxxxxxxxxxxxxxx>; stable@xxxxxxxxxxxxxxx; Kirsher, Jeffrey T
> <jeffrey.t.kirsher@xxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: [PATCH v3] igb: Free IRQs when device is hotplugged
> 
> Recently I got a Caldigit TS3 Thunderbolt 3 dock, and noticed that upon
> hotplugging my kernel would immediately crash due to igb:
> 
> [  680.825801] kernel BUG at drivers/pci/msi.c:352!
> [  680.828388] invalid opcode: 0000 [#1] SMP
> [  680.829194] Modules linked in: igb(O) thunderbolt i2c_algo_bit joydev vfat
> fat btusb btrtl btbcm btintel bluetooth ecdh_generic hp_wmi
> sparse_keymap rfkill wmi_bmof iTCO_wdt intel_rapl
> x86_pkg_temp_thermal coretemp crc32_pclmul snd_pcm rtsx_pci_ms
> mei_me snd_timer memstick snd pcspkr mei soundcore i2c_i801 tpm_tis
> psmouse shpchp wmi tpm_tis_core tpm video hp_wireless acpi_pad
> rtsx_pci_sdmmc mmc_core crc32c_intel serio_raw rtsx_pci mfd_core
> xhci_pci xhci_hcd i2c_hid i2c_core [last unloaded: igb]
> [  680.831085] CPU: 1 PID: 78 Comm: kworker/u16:1 Tainted: G           O
> 4.15.0-rc3Lyude-Test+ #6
> [  680.831596] Hardware name: HP HP ZBook Studio G4/826B, BIOS P71 Ver.
> 01.03 06/09/2017
> [  680.832168] Workqueue: kacpi_hotplug acpi_hotplug_work_fn
> [  680.832687] RIP: 0010:free_msi_irqs+0x180/0x1b0
> [  680.833271] RSP: 0018:ffffc9000030fbf0 EFLAGS: 00010286
> [  680.833761] RAX: ffff8803405f9c00 RBX: ffff88033e3d2e40 RCX:
> 000000000000002c
> [  680.834278] RDX: 0000000000000000 RSI: 00000000000000ac RDI:
> ffff880340be2178
> [  680.834832] RBP: 0000000000000000 R08: ffff880340be1ff0 R09:
> ffff8803405f9c00
> [  680.835342] R10: 0000000000000000 R11: 0000000000000040 R12:
> ffff88033d63a298
> [  680.835822] R13: ffff88033d63a000 R14: 0000000000000060 R15:
> ffff880341959000
> [  680.836332] FS:  0000000000000000(0000) GS:ffff88034f440000(0000)
> knlGS:0000000000000000
> [  680.836817] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [  680.837360] CR2: 000055e64044afdf CR3: 0000000001c09002 CR4:
> 00000000003606e0
> [  680.837954] Call Trace:
> [  680.838853]  pci_disable_msix+0xce/0xf0
> [  680.839616]  igb_reset_interrupt_capability+0x5d/0x60 [igb]
> [  680.840278]  igb_remove+0x9d/0x110 [igb]
> [  680.840764]  pci_device_remove+0x36/0xb0
> [  680.841279]  device_release_driver_internal+0x157/0x220
> [  680.841739]  pci_stop_bus_device+0x7d/0xa0
> [  680.842255]  pci_stop_bus_device+0x2b/0xa0
> [  680.842722]  pci_stop_bus_device+0x3d/0xa0
> [  680.843189]  pci_stop_and_remove_bus_device+0xe/0x20
> [  680.843627]  trim_stale_devices+0xf3/0x140
> [  680.844086]  trim_stale_devices+0x94/0x140
> [  680.844532]  trim_stale_devices+0xa6/0x140
> [  680.845031]  ? get_slot_status+0x90/0xc0
> [  680.845536]  acpiphp_check_bridge.part.5+0xfe/0x140
> [  680.846021]  acpiphp_hotplug_notify+0x175/0x200
> [  680.846581]  ? free_bridge+0x100/0x100
> [  680.847113]  acpi_device_hotplug+0x8a/0x490
> [  680.847535]  acpi_hotplug_work_fn+0x1a/0x30
> [  680.848076]  process_one_work+0x182/0x3a0
> [  680.848543]  worker_thread+0x2e/0x380
> [  680.848963]  ? process_one_work+0x3a0/0x3a0
> [  680.849373]  kthread+0x111/0x130
> [  680.849776]  ? kthread_create_worker_on_cpu+0x50/0x50
> [  680.850188]  ret_from_fork+0x1f/0x30
> [  680.850601] Code: 43 14 85 c0 0f 84 d5 fe ff ff 31 ed eb 0f 83 c5 01 39 6b 14 0f
> 86 c5 fe ff ff 8b 7b 10 01 ef e8 b7 e4 d2 ff 48 83 78 70 00 74 e3 <0f> 0b 49 8d b5
> a0 00 00 00 e8 62 6f d3 ff e9 c7 fe ff ff 48 8b
> [  680.851497] RIP: free_msi_irqs+0x180/0x1b0 RSP: ffffc9000030fbf0
> 
> As it turns out, normally the freeing of IRQs that would fix this is called
> inside of the scope of __igb_close(). However, since the device is
> already gone by the point we try to unregister the netdevice from the
> driver due to a hotplug we end up seeing that the netif isn't present
> and thus, forget to free any of the device IRQs.
> 
> So: make sure that if we're in the process of dismantling the netdev, we
> always allow __igb_close() to be called so that IRQs may be freed
> normally. Additionally, only allow igb_close() to be called from
> __igb_close() if it hasn't already been called for the given adapter.
> 
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> Fixes: 9474933caf21 ("igb: close/suspend race in netif_device_detach")
> Cc: Todd Fujinaka <todd.fujinaka@xxxxxxxxx>
> Cc: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> Changes since v2:
>   - Remove hunk in __igb_close() that was left over by accident, it's
>     not needed
> 
>  drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>