Re: [PATCH v2] pci/aer_inject: switching inject_lock to raw_spinlock_t

[Bjorn Helgaas]

On Thu, Oct 09, 2025 at 03:06:50PM +0000, Guangbo Cui wrote:
> When injecting AER errors under PREEMPT_RT, the kernel may trigger a
> lockdep warning about an invalid wait context:
> 
> ```
> [ 1850.950780] [ BUG: Invalid wait context ]
> [ 1850.951152] 6.17.0-11316-g7a405dbb0f03-dirty #7 Not tainted
> [ 1850.951457] -----------------------------
> [ 1850.951680] irq/16-PCIe PME/56 is trying to lock:
> [ 1850.952004] ffff800082865238 (inject_lock){+.+.}-{3:3}, at: aer_inj_read_config+0x38/0x1dc
> [ 1850.952731] other info that might help us debug this:
> [ 1850.952997] context-{5:5}
> [ 1850.953192] 5 locks held by irq/16-PCIe PME/56:
> [ 1850.953415]  #0: ffff800082647390 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x30/0x268
> [ 1850.953931]  #1: ffff8000826c6b38 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48
> [ 1850.954453]  #2: ffff000004bb6c58 (&data->lock){+...}-{3:3}, at: pcie_pme_irq+0x34/0xc4
> [ 1850.954949]  #3: ffff8000826c6b38 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48
> [ 1850.955420]  #4: ffff800082863d10 (pci_lock){....}-{2:2}, at: pci_bus_read_config_dword+0x5c/0xd8
> ```
> ...

If/when you update the commit log, please:

  - Update subject line to match history (use "git log --oneline")

  - Drop the timestamps because they don't help understand the issue

  - Drop the ```; just indent quoted material a couple spaces

  - Drop the `` around code names; the () after functions is enough

  - Trim it as others suggested; I appreciate the details about how
    to reproduce it, but they could go after the ---, where we'll be
    able to find them via the Link: tag