Re: [PATCH v3 2/2] PCI: Fix runtime PM usage count underflow on device unplug

[Mario Limonciello <superm1@kernel.org>]

On 6/23/25 7:19 AM, Lukas Wunner wrote:
> On Mon, Jun 23, 2025 at 06:37:33AM -0500, Mario Limonciello wrote:
>> On 6/23/25 5:11 AM, Rafael J. Wysocki wrote:
>>> On Mon, Jun 23, 2025 at 12:05???PM Lukas Wunner <lukas@wunner.de> wrote:
>>>> On Mon, Jun 23, 2025 at 09:37:07AM +0200, Lukas Wunner wrote:
>>>>> On Mon, Jun 23, 2025 at 08:43:25AM +0200, Lukas Wunner wrote:
>>>>>> On Sun, Jun 22, 2025 at 01:39:26PM -0500, Mario Limonciello wrote:
>>>>>>> I did this check and yes specifically on this PCIe port with
>>>>>>> the underflow the d3 possible lookup returns false during
>>>>>>> pcie_portdrv_remove().  It returns true during
>>>>>>> pcie_portdrv_probe().
>>>>>>
>>>>>> That's not supposed to happen.  The expectation is that
>>>>>> pci_bridge_d3_possible() always returns the same value.
>>>>>
>>>>> I'm wondering if the patch below fixes the issue?
>>
>> Yes this works, thanks!
> 
> Could you still check what the value read from the Slot Capabilities
> register is in pciehp_is_native() (if the patch is not applied)?
> 
> I guess it must be something else than "all ones" and I'd like to
> understand why.
> 
> Thanks,
> 
> Lukas

At probe:
0x00240060

At remove:
0x00000000