Re: [PATCH] PCI: Fix BAR resize for devices on a root bus

[sashiko-bot@kernel.org]

> From: Liz Fong-Jones <lizf@honeycomb.io>
> 
> pci_do_resource_release_and_resize() releases the device BARs that
> share a bridge window with the BAR being resized, but when the device
> sits directly on a root bus (pdev->bus->self == NULL) it then skips
> resource assignment entirely and returns success, leaving the BARs it
> just released unassigned (IORESOURCE_UNSET).
> 
> Skipping pbus_reassign_bridge_resources() is correct in that case --
> there is no bridge window to adjust -- but the device BARs still have
> to be reassigned. Before the BAR release was consolidated into the PCI
> core, this case worked for amdgpu because the driver released the BARs
> itself and then called pci_assign_unassigned_bus_resources()
> unconditionally after the resize, which assigns unassigned device BARs
> also on a root bus. Commit db92e3fef53e ("drm/amdgpu: Remove driver
> [ ... ]
> it exactly once.
> 
> Fixes: 337b1b566db0 ("PCI: Fix restoring BARs on BAR resize rollback path")
> Cc: stable@vger.kernel.org # v6.19+
> Signed-off-by: Liz Fong-Jones <lizf@honeycomb.io>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260705-pci-rebar-root-bus-v1-1-55df70cbdd88@honeycomb.io?part=1