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

[Bjorn Helgaas <helgaas@kernel.org>]

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
>