On Tue, Jun 18, 2024 at 10:12:32AM -0600, Keith Busch wrote: > On Tue, Jun 18, 2024 at 12:54:55PM +0200, Lukas Wunner wrote: > > However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also > > called on a DPC event. Commit 53b54ad074de ("PCI/DPC: Await readiness > > of secondary bus after reset"), which introduced that, failed to > > appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a > > reference on the child device because dpc_handler() and pciehp may > > indeed run concurrently. The commit was backported to v5.10+ stable > > kernels, so that's the oldest one affected. > > Caution on applying this to 5.10 and 5.15 stable branches: they don't > have the fancy "__free" cleanup you're using here. The newer active > stables are okay, though. I'll let Greg & Sasha know when they start applying this to stable kernels that ced085ef369a is a prerequisite for v5.10-stable and v5.15-stable. I can rework the patch if they don't want to apply ced085ef369a to these older versions. Thanks, Lukas