On Mon, Jun 15, 2020 at 09:32:49AM -0500, Ian May wrote: > Currently when a hotplug interrupt and AER recovery triggers simultaneously > the following deadlock can occur. > > Hotplug AER > ---------------------------- --------------------------- > device_lock(&dev->dev) down_write(&ctrl->reset_lock) > down_read(&ctrl->reset_lock) device_lock(&dev->dev) > > This patch adds a reset_lock and reset_unlock hotplug_slot_op. > This would allow the controller reset_lock/reset_unlock to be moved > from pciehp_reset_slot to pci_slot_reset function allowing the controller > reset_lock to be acquired before the device lock allowing for both hotplug > and AER to grab the reset_lock and device lock in proper order. I've posted a patch to address such issues on Mar 31, just haven't gotten around to respin it with a proper commit message: https://lore.kernel.org/linux-pci/20200331130139.46oxbade6rcbaicb@xxxxxxxxx/ I've solved it by moving the reset lock into struct pci_slot. I think that's simpler than adding two callbacks. Do you think the AER deadlock could be fixed based on my approach? Thanks, Lukas
