| Message ID | 20240209140841.1854711-1-stanislaw.gruszka@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI/AER: Block runtime suspend when handling errors | expand |
On Fri, Feb 9, 2024 at 3:09 PM Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> wrote: > > PM runtime can be done simultaneously with AER error handling. > Avoid that by using pm_runtime_get_sync() before and pm_runtime_put() > after reset in pcie_do_recovery() for all recovering devices. > > pm_runtime_get_sync() will increase dev->power.usage_count counter > to prevent any possible future request to runtime suspend a device, > as well as resume device is was in D3hot state. > > I tested with igc device by doing simultaneous aer_inject and > rpm suspend/resume via /sys/bus/pci/devices/PCI_ID/power/control > and can reproduce: > > igc 0000:02:00.0: not ready 65535ms after bus reset; giving up > pcieport 0000:00:1c.2: AER: Root Port link has been reset (-25) > pcieport 0000:00:1c.2: AER: subordinate device reset failed > pcieport 0000:00:1c.2: AER: device recovery failed > igc 0000:02:00.0: Unable to change power state from D3hot to D0, device inaccessible > > The problem disappears when applied this patch. > > Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> Looks reasonable to me: Acked-by: Rafael J. Wysocki <rafael@kernel.org> > --- > RFC -> v1: > add runtime callbacks to pcie_do_recovery(), this covers DPC case > as well as case of recovering multiple devices under same port. > > drivers/pci/pcie/err.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > index 59c90d04a609..705893b5f7b0 100644 > --- a/drivers/pci/pcie/err.c > +++ b/drivers/pci/pcie/err.c > @@ -13,6 +13,7 @@ > #define dev_fmt(fmt) "AER: " fmt > > #include <linux/pci.h> > +#include <linux/pm_runtime.h> > #include <linux/module.h> > #include <linux/kernel.h> > #include <linux/errno.h> > @@ -85,6 +86,18 @@ static int report_error_detected(struct pci_dev *dev, > return 0; > } > > +static int pci_pm_runtime_get_sync(struct pci_dev *pdev, void *data) > +{ > + pm_runtime_get_sync(&pdev->dev); > + return 0; > +} > + > +static int pci_pm_runtime_put(struct pci_dev *pdev, void *data) > +{ > + pm_runtime_put(&pdev->dev); > + return 0; > +} > + > static int report_frozen_detected(struct pci_dev *dev, void *data) > { > return report_error_detected(dev, pci_channel_io_frozen, data); > @@ -207,6 +220,8 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > else > bridge = pci_upstream_bridge(dev); > > + pci_walk_bridge(bridge, pci_pm_runtime_get_sync, NULL); > + > pci_dbg(bridge, "broadcast error_detected message\n"); > if (state == pci_channel_io_frozen) { > pci_walk_bridge(bridge, report_frozen_detected, &status); > @@ -251,10 +266,15 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > pcie_clear_device_status(dev); > pci_aer_clear_nonfatal_status(dev); > } > + > + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); > + > pci_info(bridge, "device recovery successful\n"); > return status; > > failed: > + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); > + > pci_uevent_ers(bridge, PCI_ERS_RESULT_DISCONNECT); > > /* TODO: Should kernel panic here? */ > -- > 2.34.1 >
On 2/9/24 6:08 AM, Stanislaw Gruszka wrote: > PM runtime can be done simultaneously with AER error handling. > Avoid that by using pm_runtime_get_sync() before and pm_runtime_put() > after reset in pcie_do_recovery() for all recovering devices. > > pm_runtime_get_sync() will increase dev->power.usage_count counter > to prevent any possible future request to runtime suspend a device, > as well as resume device is was in D3hot state. runtime suspend a device or resume a device that was in D3hot state. > > I tested with igc device by doing simultaneous aer_inject and > rpm suspend/resume via /sys/bus/pci/devices/PCI_ID/power/control > and can reproduce: > > igc 0000:02:00.0: not ready 65535ms after bus reset; giving up > pcieport 0000:00:1c.2: AER: Root Port link has been reset (-25) > pcieport 0000:00:1c.2: AER: subordinate device reset failed > pcieport 0000:00:1c.2: AER: device recovery failed > igc 0000:02:00.0: Unable to change power state from D3hot to D0, device inaccessible > > The problem disappears when applied this patch. > > Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> > --- since it is a bug fix, may be Cc: stable@vger.kernel.org Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> > RFC -> v1: > add runtime callbacks to pcie_do_recovery(), this covers DPC case > as well as case of recovering multiple devices under same port. > > drivers/pci/pcie/err.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > index 59c90d04a609..705893b5f7b0 100644 > --- a/drivers/pci/pcie/err.c > +++ b/drivers/pci/pcie/err.c > @@ -13,6 +13,7 @@ > #define dev_fmt(fmt) "AER: " fmt > > #include <linux/pci.h> > +#include <linux/pm_runtime.h> > #include <linux/module.h> > #include <linux/kernel.h> > #include <linux/errno.h> > @@ -85,6 +86,18 @@ static int report_error_detected(struct pci_dev *dev, > return 0; > } > > +static int pci_pm_runtime_get_sync(struct pci_dev *pdev, void *data) > +{ > + pm_runtime_get_sync(&pdev->dev); > + return 0; > +} > + > +static int pci_pm_runtime_put(struct pci_dev *pdev, void *data) > +{ > + pm_runtime_put(&pdev->dev); > + return 0; > +} > + > static int report_frozen_detected(struct pci_dev *dev, void *data) > { > return report_error_detected(dev, pci_channel_io_frozen, data); > @@ -207,6 +220,8 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > else > bridge = pci_upstream_bridge(dev); > > + pci_walk_bridge(bridge, pci_pm_runtime_get_sync, NULL); > + > pci_dbg(bridge, "broadcast error_detected message\n"); > if (state == pci_channel_io_frozen) { > pci_walk_bridge(bridge, report_frozen_detected, &status); > @@ -251,10 +266,15 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > pcie_clear_device_status(dev); > pci_aer_clear_nonfatal_status(dev); > } > + > + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); > + > pci_info(bridge, "device recovery successful\n"); > return status; > > failed: > + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); > + > pci_uevent_ers(bridge, PCI_ERS_RESULT_DISCONNECT); > > /* TODO: Should kernel panic here? */
On Fri, Feb 09, 2024 at 07:45:05AM -0800, Kuppuswamy Sathyanarayanan wrote: > > On 2/9/24 6:08 AM, Stanislaw Gruszka wrote: > > PM runtime can be done simultaneously with AER error handling. > > Avoid that by using pm_runtime_get_sync() before and pm_runtime_put() > > after reset in pcie_do_recovery() for all recovering devices. > > > > pm_runtime_get_sync() will increase dev->power.usage_count counter > > to prevent any possible future request to runtime suspend a device, > > as well as resume device is was in D3hot state. > runtime suspend a device or resume a device that was in D3hot state. I think "or" is not proper here, since both: resume and prevention of suspend are done. I'll reword this way: pm_runtime_get_sync() will increase dev->power.usage_count counter to prevent any possible future request to runtime suspend a device It will also resume a device, if it was previously in D3hot state. Hope that's clearer. Thanks Stanislaw
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index 59c90d04a609..705893b5f7b0 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -13,6 +13,7 @@ #define dev_fmt(fmt) "AER: " fmt #include <linux/pci.h> +#include <linux/pm_runtime.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/errno.h> @@ -85,6 +86,18 @@ static int report_error_detected(struct pci_dev *dev, return 0; } +static int pci_pm_runtime_get_sync(struct pci_dev *pdev, void *data) +{ + pm_runtime_get_sync(&pdev->dev); + return 0; +} + +static int pci_pm_runtime_put(struct pci_dev *pdev, void *data) +{ + pm_runtime_put(&pdev->dev); + return 0; +} + static int report_frozen_detected(struct pci_dev *dev, void *data) { return report_error_detected(dev, pci_channel_io_frozen, data); @@ -207,6 +220,8 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, else bridge = pci_upstream_bridge(dev); + pci_walk_bridge(bridge, pci_pm_runtime_get_sync, NULL); + pci_dbg(bridge, "broadcast error_detected message\n"); if (state == pci_channel_io_frozen) { pci_walk_bridge(bridge, report_frozen_detected, &status); @@ -251,10 +266,15 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, pcie_clear_device_status(dev); pci_aer_clear_nonfatal_status(dev); } + + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); + pci_info(bridge, "device recovery successful\n"); return status; failed: + pci_walk_bridge(bridge, pci_pm_runtime_put, NULL); + pci_uevent_ers(bridge, PCI_ERS_RESULT_DISCONNECT); /* TODO: Should kernel panic here? */
PM runtime can be done simultaneously with AER error handling. Avoid that by using pm_runtime_get_sync() before and pm_runtime_put() after reset in pcie_do_recovery() for all recovering devices. pm_runtime_get_sync() will increase dev->power.usage_count counter to prevent any possible future request to runtime suspend a device, as well as resume device is was in D3hot state. I tested with igc device by doing simultaneous aer_inject and rpm suspend/resume via /sys/bus/pci/devices/PCI_ID/power/control and can reproduce: igc 0000:02:00.0: not ready 65535ms after bus reset; giving up pcieport 0000:00:1c.2: AER: Root Port link has been reset (-25) pcieport 0000:00:1c.2: AER: subordinate device reset failed pcieport 0000:00:1c.2: AER: device recovery failed igc 0000:02:00.0: Unable to change power state from D3hot to D0, device inaccessible The problem disappears when applied this patch. Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> --- RFC -> v1: add runtime callbacks to pcie_do_recovery(), this covers DPC case as well as case of recovering multiple devices under same port. drivers/pci/pcie/err.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)