Re: [PATCH] pci: don't fallback to bus reset after failed slot reset

Bjorn Helgaas
2026-04-24T16:11:38Z

On Tue, Apr 21, 2026 at 08:06:44AM -0700, Keith Busch wrote:
> From: Keith Busch <kbusch@kernel.org>
>
> If a bus has hotplug slots that implement the slot's reset_slot
> callback, it is not safe to do the non-slot specific bus reset, so don't
> fallback to it. If a slot reset does fail, the subsequent bus reset will
> attempt a 2nd link reset on top of previous and fail to handle the
> hotplug events.
>
> Fixes: 8238cb69c01fe ("PCI: Make reset_subordinate hotplug safe")
> Signed-off-by: Keith Busch <kbusch@kernel.org>

Applied to pci/reset for v7.2, thanks! Will be rebased after
v7.1-rc1.

> ---
> drivers/pci/pci.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 8f7cfcc000901..d34266651ad09 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5607,13 +5607,14 @@ static int pci_try_reset_bus(struct pci_bus *bus)
> * reset for affected devices
> *
> * This function will first try to reset the slots on this bus if the method is
> - * available. If slot reset fails or is not available, this will fall back to a
> + * available. If slot reset is not available, this will fall back to a
> * secondary bus reset.
> */
> static int pci_reset_bridge(struct pci_dev *bridge, bool restore)
> {
> struct pci_bus *bus = bridge->subordinate;
> struct pci_slot *slot;
> + int ret = 0;
>
> if (!bus)
> return -ENOTTY;
> @@ -5627,19 +5628,17 @@ static int pci_reset_bridge(struct pci_dev *bridge, bool restore)
> goto bus_reset;
>
> list_for_each_entry(slot, &bus->slots, list) {
> - int ret;
> -
> if (restore)
> ret = pci_try_reset_slot(slot);
> else
> ret = pci_slot_reset(slot, PCI_RESET_DO_RESET);
>
> if (ret)
> - goto bus_reset;
> + break;
> }
>
> mutex_unlock(&pci_slot_mutex);
> - return 0;
> + return ret;
> bus_reset:
> mutex_unlock(&pci_slot_mutex);
>
> --
> 2.52.0
>