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From: Bjorn Helgaas <helgaas@kernel.org>
To: Alex Williamson <alex.williamson@redhat.com>
Cc: bhelgaas@google.com, rafael@kernel.org,
	linux-pci@vger.kernel.org, linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] PCI/PM: Elevate PM usage during reset probing
Date: Wed, 23 Apr 2025 16:10:55 -0500	[thread overview]
Message-ID: <20250423211055.GA455833@bhelgaas> (raw)
In-Reply-To: <20250422230534.2295291-1-alex.williamson@redhat.com>

On Tue, Apr 22, 2025 at 05:05:30PM -0600, Alex Williamson wrote:
> I encountered a confusing scenario where a device reports NoSoftRst- and
> doesn't have any associated quirks to set PCI_DEV_FLAGS_NO_PM_RESET, but
> it refuses to probe for PM reset support using the sysfs reset_method
> attribute.  The reason turns out to be that we don't increment the usage
> count while probing, the driver has the device in D3, where this system
> seems to support D3cold, and the PM control register is read back as
> 0xffff.
> 
> The cleanup __free helper seems to be the cleanest solution here, versus
> refactoring to a common exit point or wrappers around reset_fn, but feel
> free to suggest otherwise.  I see a couple potential other use cases for
> this helper in the vfio code.
> 
> Please review.  Thanks,
> 
> Alex
> 
> Alex Williamson (2):
>   PM: runtime: Define pm_runtime_put cleanup helper
>   PCI: Increment PM usage counter when probing reset methods
> 
>  drivers/pci/pci-sysfs.c    | 3 +++
>  include/linux/pm_runtime.h | 2 ++
>  2 files changed, 5 insertions(+)

Applied to pci/pm for v6.16, thanks, Alex!

      parent reply	other threads:[~2025-04-23 21:10 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-22 23:05 [PATCH 0/2] PCI/PM: Elevate PM usage during reset probing Alex Williamson
2025-04-22 23:05 ` [PATCH 1/2] PM: runtime: Define pm_runtime_put cleanup helper Alex Williamson
2025-04-23 12:21   ` Rafael J. Wysocki
2025-04-22 23:05 ` [PATCH 2/2] PCI: Increment PM usage counter when probing reset methods Alex Williamson
2025-04-23 21:10 ` Bjorn Helgaas [this message]

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