[PATCH net] pds_core: cancel pending PCI reset work on AER recovery

[PATCH net] pds_core: cancel pending PCI reset work on AER recovery

[Nikhil P. Rao]

pdsc_check_pci_health() queues pci_reset_work when it sees a broken PCI
connection, and nothing cancels it. When the PCI core starts AER
recovery, pdsc_pci_error_detected() runs pdsc_reset_prepare() and
recovers the device, but a pci_reset_work queued just before is left
pending. If it runs after recovery released the device lock, it resets a
device the driver now considers healthy, bouncing the link for no reason.

Cancel pci_reset_work in pdsc_pci_error_detected() after
pdsc_reset_prepare(), which has already stopped the health thread so it
cannot requeue the work. cancel_work_sync() is safe under the device
lock here because pdsc_pci_reset_thread() uses pci_try_reset_function(),
which returns instead of blocking on the lock. Only PFs initialize
pci_reset_work, so guard the cancel with !is_virtfn.

Fixes: 81665adf25d2 ("pds_core: Fix pdsc_check_pci_health function to use work thread")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260714180223.1642792-2-nikhil.rao%40amd.com?part=1
Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com>
---
 drivers/net/ethernet/amd/pds_core/main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
index 8d94a4d70395..1bdfa9893904 100644
--- a/drivers/net/ethernet/amd/pds_core/main.c
+++ b/drivers/net/ethernet/amd/pds_core/main.c
@@ -555,7 +555,11 @@ static pci_ers_result_t pdsc_pci_error_detected(struct pci_dev *pdev,
 						pci_channel_state_t error)
 {
 	if (error == pci_channel_io_frozen) {
+		struct pdsc *pdsc = pci_get_drvdata(pdev);
+
 		pdsc_reset_prepare(pdev);
+		if (!pdev->is_virtfn)
+			cancel_work_sync(&pdsc->pci_reset_work);
 		return PCI_ERS_RESULT_NEED_RESET;
 	}
 
-- 
2.43.0

Re: [PATCH net] pds_core: cancel pending PCI reset work on AER recovery

[Jacob Keller]

On 7/27/2026 10:00 AM, Nikhil P. Rao wrote:
> pdsc_check_pci_health() queues pci_reset_work when it sees a broken PCI
> connection, and nothing cancels it. When the PCI core starts AER
> recovery, pdsc_pci_error_detected() runs pdsc_reset_prepare() and
> recovers the device, but a pci_reset_work queued just before is left
> pending. If it runs after recovery released the device lock, it resets a
> device the driver now considers healthy, bouncing the link for no reason.
> 
> Cancel pci_reset_work in pdsc_pci_error_detected() after
> pdsc_reset_prepare(), which has already stopped the health thread so it
> cannot requeue the work. cancel_work_sync() is safe under the device
> lock here because pdsc_pci_reset_thread() uses pci_try_reset_function(),
> which returns instead of blocking on the lock. Only PFs initialize
> pci_reset_work, so guard the cancel with !is_virtfn.
> 
> Fixes: 81665adf25d2 ("pds_core: Fix pdsc_check_pci_health function to use work thread")
> Reported-by: sashiko-bot <sashiko-bot@kernel.org>
> Closes: https://sashiko.dev/#/patchset/20260714180223.1642792-2-nikhil.rao%40amd.com?part=1
> Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com>
> ---
>  drivers/net/ethernet/amd/pds_core/main.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
> index 8d94a4d70395..1bdfa9893904 100644
> --- a/drivers/net/ethernet/amd/pds_core/main.c
> +++ b/drivers/net/ethernet/amd/pds_core/main.c
> @@ -555,7 +555,11 @@ static pci_ers_result_t pdsc_pci_error_detected(struct pci_dev *pdev,
>  						pci_channel_state_t error)
>  {
>  	if (error == pci_channel_io_frozen) {
> +		struct pdsc *pdsc = pci_get_drvdata(pdev);
> +
>  		pdsc_reset_prepare(pdev);
> +		if (!pdev->is_virtfn)
> +			cancel_work_sync(&pdsc->pci_reset_work);
>  		return PCI_ERS_RESULT_NEED_RESET;
>  	}
>  

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>