Re: [PATCH v4 1/1] bus: mhi: host: Move IRQ allocation to controller registration phase

Kalle Valo
2022-07-18T11:15:41Z

+ ath11k list

Manivannan Sadhasivam <mani@kernel.org> writes:

> On Thu, Jun 23, 2022 at 10:43:03AM +0800, Qiang Yu wrote:
>> During runtime, the MHI endpoint may be powered up/down several times.
>> So instead of allocating and destroying the IRQs all the time, let's just
>> enable/disable IRQs during power up/down.
>>
>> The IRQs will be allocated during mhi_register_controller() and freed
>> during mhi_unregister_controller(). This works well for things like PCI
>> hotplug also as once the PCI device gets removed, the controller will
>> get unregistered. And once it comes back, it will get registered back
>> and even if the IRQ configuration changes (MSI), that will get accounted.
>>
>> Signed-off-by: Qiang Yu <quic_qianyu@quicinc.com>
>
> Applied to mhi-next!

I did a bisect and this patch breaks ath11k during rmmod. I'm on
vacation right now so I can't investigate in detail but more info below.

[ 66.939878] rmmod ath11k_pci
[ 67.606269] general protection fault, probably for non-canonical
address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN
PTI
[ 67.606328] KASAN: null-ptr-deref in range
[0x0000000000000000-0x0000000000000007]
[ 67.606387] CPU: 3 PID: 1463 Comm: rmmod Not tainted 5.19.0-rc1+ #669
[ 67.606456] Hardware name: Intel(R) Client Systems
NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021
[ 67.606492] RIP: 0010:mhi_irq_handler+0x61/0x370 [mhi]
[ 67.606565] Code: 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 9b 02 00
00 49 8b ad 20 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea
03 <80> 3c 02 00 0f 85 bd 02 00 00 48 8d 7b 10 48 8b 6d 00 48 b8 00 00
[ 67.606639] RSP: 0018:ffffc900042ffba8 EFLAGS: 00010046
[ 67.606706] RAX: dffffc0000000000 RBX: ffff88812e1e2800 RCX:
0000000000000001
[ 67.606742] RDX: 0000000000000000 RSI: ffff88812e1e2800 RDI:
ffff888110e8d120
[ 67.606776] RBP: 0000000000000000 R08: 0000000000000001 R09:
ffffffff86ac17af
[ 67.606810] R10: fffffbfff0d582f5 R11: 0000000000000001 R12:
ffff88812c3afb80
[ 67.606845] R13: ffff888110e8d000 R14: ffff88811ddba800 R15:
ffff88812e1e2800
[ 67.606880] FS: 00007fef00794740(0000) GS:ffff888234200000(0000)
knlGS:0000000000000000
[ 67.606915] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 67.606950] CR2: 000055df2323b788 CR3: 0000000109844001 CR4:
00000000003706e0
[ 67.606987] Call Trace:
[ 67.607021] <TASK>
[ 67.607056] __free_irq+0x590/0x9d0
[ 67.607099] ? slab_free_freelist_hook+0xf0/0x1a0
[ 67.607136] free_irq+0x7b/0x110
[ 67.607171] mhi_deinit_free_irq+0x14e/0x260 [mhi]
[ 67.607210] mhi_unregister_controller+0x69/0x290 [mhi]
[ 67.607249] ath11k_mhi_unregister+0x2b/0x70 [ath11k_pci]
[ 67.607284] ath11k_pci_remove+0x107/0x2a0 [ath11k_pci]
[ 67.607321] pci_device_remove+0x89/0x1b0
[ 67.607359] device_release_driver_internal+0x3bc/0x600
[ 67.607400] driver_detach+0xbc/0x180
[ 67.607439] bus_remove_driver+0xe2/0x2d0
[ 67.607476] pci_unregister_driver+0x21/0x250
[ 67.607512] __do_sys_delete_module+0x307/0x4b0
[ 67.607548] ? free_module+0x4e0/0x4e0
[ 67.607584] ? lockdep_hardirqs_on_prepare.part.0+0x18c/0x370
[ 67.607618] ? syscall_enter_from_user_mode+0x1d/0x50
[ 67.607653] ? lockdep_hardirqs_on+0x79/0x100
[ 67.607688] do_syscall_64+0x35/0x80
[ 67.607723] entry_SYSCALL_64_after_hwframe+0x46/0xb0
[ 67.607758] RIP: 0033:0x7fef008e1a6b
[ 67.607794] Code: 73 01 c3 48 8b 0d 25 c4 0c 00 f7 d8 64 89 01 48 83
c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 b0 00 00 00 0f
05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f5 c3 0c 00 f7 d8 64 89 01 48
[ 67.607836] RSP: 002b:00007ffdd5803a38 EFLAGS: 00000206 ORIG_RAX:
00000000000000b0
[ 67.607873] RAX: ffffffffffffffda RBX: 000055c0d3f107a0 RCX:
00007fef008e1a6b
[ 67.607961] RDX: 000000000000000a RSI: 0000000000000800 RDI:
000055c0d3f10808
[ 67.607995] RBP: 00007ffdd5803a98 R08: 0000000000000000 R09:
0000000000000000
[ 67.608029] R10: 00007fef0095dac0 R11: 0000000000000206 R12:
00007ffdd5803c70
[ 67.608063] R13: 00007ffdd5804eb7 R14: 000055c0d3f0f2a0 R15:
000055c0d3f107a0
[ 67.608100] </TASK>
[ 67.608134] Modules linked in: ath11k_pci(-) ath11k mac80211 libarc4
cfg80211 qmi_helpers qrtr_mhi mhi qrtr nvme nvme_core
[ 67.608185] ---[ end trace 0000000000000000 ]---
[ 67.608186] RIP: 0010:mhi_irq_handler+0x61/0x370 [mhi]
[ 67.608192] Code: 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 9b 02 00
00 49 8b ad 20 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea
03 <80> 3c 02 00 0f 85 bd 02 00 00 48 8d 7b 10 48 8b 6d 00 48 b8 00 00
[ 67.608194] RSP: 0018:ffffc900042ffba8 EFLAGS: 00010046
[ 67.608196] RAX: dffffc0000000000 RBX: ffff88812e1e2800 RCX:
0000000000000001
[ 67.608197] RDX: 0000000000000000 RSI: ffff88812e1e2800 RDI:
ffff888110e8d120
[ 67.608198] RBP: 0000000000000000 R08: 0000000000000001 R09:
ffffffff86ac17af
[ 67.608199] R10: fffffbfff0d582f5 R11: 0000000000000001 R12:
ffff88812c3afb80
[ 67.608200] R13: ffff888110e8d000 R14: ffff88811ddba800 R15:
ffff88812e1e2800
[ 67.608201] FS: 00007fef00794740(0000) GS:ffff888234200000(0000)
knlGS:0000000000000000
[ 67.608203] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 67.608204] CR2: 000055df2323b788 CR3: 0000000109844001 CR4:
00000000003706e0
[ 67.608206] Kernel panic - not syncing: Fatal exception
[ 67.608665] Kernel Offset: 0xa00000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 67.608704] Rebooting in 10 seconds..

git bisect start
# bad: [9df125af0822d3e2bde7508e9536d67ab541a166] bus: mhi: ep: Check dev_set_name() return value
git bisect bad 9df125af0822d3e2bde7508e9536d67ab541a166
# good: [178329d4d635fb1848cc7ca1803dee5a634cde0d] bus: mhi: host: pci_generic: Add support for Quectel EM120 FCCL modem
git bisect good 178329d4d635fb1848cc7ca1803dee5a634cde0d
# bad: [1227d2a20cd7319fb45c62fab4b252600e0308bf] bus: mhi: host: Move IRQ allocation to controller registration phase
git bisect bad 1227d2a20cd7319fb45c62fab4b252600e0308bf
# good: [b7ce716254315dffcfce60e149ddd022c8a60345] bus: mhi: host: pci_generic: Add Cinterion MV31-W with new baseline
git bisect good b7ce716254315dffcfce60e149ddd022c8a60345
# first bad commit: [1227d2a20cd7319fb45c62fab4b252600e0308bf] bus: mhi: host: Move IRQ allocation to controller registration phase