Re: Lockdep annotation introduced warn in VMD driver

[Nirmal Patel <nirmal.patel@linux.intel.com>]

On Tue, 28 May 2024 15:36:54 +0300
Imre Deak <imre.deak@intel.com> wrote:

> Hi,
> 
> commit 7e89efc6e9e402839643cb297bab14055c547f07
> Author: Dave Jiang <dave.jiang@intel.com>
> Date:   Thu May 2 09:57:31 2024 -0700
> 
>     PCI: Lock upstream bridge for pci_reset_function()
> 
> introduced the WARN below in the VMD driver, see [1] for the full log.
> Not sure if the annotation is incorrect or the VMD driver is missing
> the lock, CC'ing VMD folks.
> 
> --Imre
Can you please provide repro steps and some background on the setup?

-nirmal
> 
> https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_134112v1/bat-adlp-11/boot0.txt
> 
> <4>[   17.354071] WARNING: CPU: 0 PID: 1 at drivers/pci/pci.c:4886
> pci_bridge_secondary_bus_reset+0x5d/0x70 <4>[   17.354095] Modules
> linked in: <4>[   17.354104] CPU: 0 PID: 1 Comm: swapper/0 Not
> tainted 6.10.0-rc1-Patchwork_134112v1-gabaeae202dfb+ #1 <4>[
> 17.354128] Hardware name: Intel Corporation Alder Lake Client
> Platform/AlderLake-P LP5 RVP, BIOS RPLPFWI1.R00.4035.A00.2301200723
> 01/20/2023 <4>[   17.354153] RIP:
> 0010:pci_bridge_secondary_bus_reset+0x5d/0x70 <4>[   17.354167] Code:
> c3 cc cc cc cc 48 89 ef 48 c7 c6 78 55 44 82 5d e9 d8 c6 ff ff 48 8d
> bf 48 08 00 00 be ff ff ff ff e8 97 10 5f 00 85 c0 75 b5 <0f> 0b eb
> b1 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 <4>[
> 17.354199] RSP: 0000:ffffc90000097ca0 EFLAGS: 00010246 <4>[
> 17.354210] RAX: 0000000000000000 RBX: ffff888105604000 RCX:
> 0000000000000000 <4>[   17.354224] RDX: 0000000080000000 RSI:
> ffffffff82421c40 RDI: ffffffff82441c4c <4>[   17.354238] RBP:
> ffff888105601000 R08: 0000000000000001 R09: 0000000000000000 <4>[
> 17.354251] R10: 0000000000000001 R11: ffff8881008c8040 R12:
> 0000000000000000 <4>[   17.354264] R13: 0000000000000020 R14:
> 000000000000007f R15: ffff888105615c28 <4>[   17.354283] FS:
> 0000000000000000(0000) GS:ffff8882a6e00000(0000)
> knlGS:0000000000000000 <4>[   17.354313] CS:  0010 DS: 0000 ES: 0000
> CR0: 0000000080050033 <4>[   17.354334] CR2: ffff8882afbff000 CR3:
> 000000000663a000 CR4: 0000000000f50ef0 <4>[   17.354348] PKRU:
> 55555554 <4>[   17.354355] Call Trace: <4>[   17.354361]  <TASK> <4>[
>   17.354367]  ? __warn+0x8c/0x190 <4>[   17.354380]  ?
> pci_bridge_secondary_bus_reset+0x5d/0x70 <4>[   17.354392]  ?
> report_bug+0x1f8/0x200 <4>[   17.354405]  ? handle_bug+0x3c/0x70 <4>[
>   17.354415]  ? exc_invalid_op+0x18/0x70 <4>[   17.354424]  ?
> asm_exc_invalid_op+0x1a/0x20 <4>[   17.354438]  ?
> pci_bridge_secondary_bus_reset+0x5d/0x70 <4>[   17.354451]
> pci_reset_bus+0x1d8/0x270 <4>[   17.354461]  vmd_probe+0x778/0xa10
> <4>[   17.354474]  pci_device_probe+0x95/0x120 <4>[   17.354484]
> really_probe+0xd9/0x370 <4>[   17.354496]  ?
> __pfx___driver_attach+0x10/0x10 <4>[   17.354505]
> __driver_probe_device+0x73/0x150 <4>[   17.354516]
> driver_probe_device+0x19/0xa0 <4>[   17.354525]
> __driver_attach+0xb6/0x180 <4>[   17.354534]  ?
> __pfx___driver_attach+0x10/0x10 <4>[   17.354544]
> bus_for_each_dev+0x77/0xd0 <4>[   17.354555]
> bus_add_driver+0x110/0x240 <4>[   17.354566]
> driver_register+0x5b/0x110 <4>[   17.354575]  ?
> __pfx_vmd_drv_init+0x10/0x10 <4>[   17.354587]
> do_one_initcall+0x5c/0x2b0 <4>[   17.354600]
> kernel_init_freeable+0x18e/0x340 <4>[   17.354612]  ?
> __pfx_kernel_init+0x10/0x10 <4>[   17.354623]  kernel_init+0x15/0x130
> <4>[   17.354631]  ret_from_fork+0x2c/0x50 <4>[   17.354641]  ?
> __pfx_kernel_init+0x10/0x10 <4>[   17.354650]
> ret_from_fork_asm+0x1a/0x30 <4>[   17.354663]  </TASK> <4>[
> 17.354669] irq event stamp: 28577685 <4>[   17.354677] hardirqs last
> enabled at (28577693): [<ffffffff8117c060>]
> console_unlock+0x110/0x120 <4>[   17.354697] hardirqs last disabled
> at (28577700): [<ffffffff8117c045>] console_unlock+0xf5/0x120 <4>[
> 17.354713] softirqs last  enabled at (28577176): [<ffffffff810df29c>]
> handle_softirqs+0x2ec/0x3f0 <4>[   17.354731] softirqs last disabled
> at (28577167): [<ffffffff810dfa17>] irq_exit_rcu+0x87/0xc0 <4>[
> 17.354747] ---[ end trace 0000000000000000 ]---
> 
> <4>[   17.487274] =====================================
> <4>[   17.487277] WARNING: bad unlock balance detected!
> <4>[   17.487279] 6.10.0-rc1-Patchwork_134112v1-gabaeae202dfb+ #1
> Tainted: G        W <4>[   17.487282]
> ------------------------------------- <4>[   17.487284] swapper/0/1
> is trying to release lock (10000:e1:00.0) at: <4>[   17.487287]
> [<ffffffff8176b377>] pci_cfg_access_unlock+0x57/0x60 <4>[
> 17.487292] but there are no more locks to release! <4>[   17.487294]
>                   other info that might help us debug this:
> <4>[   17.487297] 2 locks held by swapper/0/1:
> <4>[   17.487299]  #0: ffff888102c1c1b0 (&dev->mutex){....}-{3:3},
> at: __driver_attach+0xab/0x180 <4>[   17.487306]  #1:
> ffff8881056041b0 (&dev->mutex){....}-{3:3}, at:
> pci_dev_trylock+0x19/0x50 <4>[   17.487312] stack backtrace:
> <4>[   17.487314] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W
>        6.10.0-rc1-Patchwork_134112v1-gabaeae202dfb+ #1 <4>[
> 17.487318] Hardware name: Intel Corporation Alder Lake Client
> Platform/AlderLake-P LP5 RVP, BIOS RPLPFWI1.R00.4035.A00.2301200723
> 01/20/2023 <4>[   17.487322] Call Trace: <4>[   17.487324]  <TASK>
> <4>[   17.487325]  dump_stack_lvl+0x82/0xd0 <4>[   17.487329]
> lock_release+0x20b/0x2d0 <4>[   17.487334]  pci_bus_unlock+0x25/0x40
> <4>[   17.487337]  pci_reset_bus+0x1eb/0x270
> <4>[   17.487340]  vmd_probe+0x778/0xa10
> <4>[   17.487344]  pci_device_probe+0x95/0x120
> <4>[   17.487346]  really_probe+0xd9/0x370
> <4>[   17.487349]  ? __pfx___driver_attach+0x10/0x10
> <4>[   17.487352]  __driver_probe_device+0x73/0x150
> <4>[   17.487354]  driver_probe_device+0x19/0xa0
> <4>[   17.487357]  __driver_attach+0xb6/0x180
> <4>[   17.487359]  ? __pfx___driver_attach+0x10/0x10
> <4>[   17.487362]  bus_for_each_dev+0x77/0xd0
> <4>[   17.487365]  bus_add_driver+0x110/0x240
> <4>[   17.487369]  driver_register+0x5b/0x110
> <4>[   17.487371]  ? __pfx_vmd_drv_init+0x10/0x10
> <4>[   17.487374]  do_one_initcall+0x5c/0x2b0
> <4>[   17.487378]  kernel_init_freeable+0x18e/0x340
> <4>[   17.487381]  ? __pfx_kernel_init+0x10/0x10
> <4>[   17.487384]  kernel_init+0x15/0x130
> <4>[   17.487387]  ret_from_fork+0x2c/0x50
> <4>[   17.487390]  ? __pfx_kernel_init+0x10/0x10
> <4>[   17.487392]  ret_from_fork_asm+0x1a/0x30
> <4>[   17.487396]  </TASK>
>