sfc: Fix EEH with legacy interrupts.
PCI legacy interrupts are level-triggered, and we cannot mask them up
on an isolated device. Instead, disable the IRQ at the controller
until we have recovered.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index 46cc11d..787c9eb 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -23,6 +23,7 @@
#include <linux/gfp.h>
#include <linux/cpu_rmap.h>
#include <linux/aer.h>
+#include <linux/interrupt.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
@@ -1427,6 +1428,10 @@
BUG_ON(efx->state == STATE_DISABLED);
+ if (efx->eeh_disabled_legacy_irq) {
+ enable_irq(efx->legacy_irq);
+ efx->eeh_disabled_legacy_irq = false;
+ }
if (efx->legacy_irq)
efx->legacy_irq_enabled = true;
efx_nic_enable_interrupts(efx);
@@ -2365,7 +2370,7 @@
* Returns 0 if the recovery mechanisms are unsuccessful.
* Returns a non-zero value otherwise.
*/
-static int efx_try_recovery(struct efx_nic *efx)
+int efx_try_recovery(struct efx_nic *efx)
{
#ifdef CONFIG_EEH
/* A PCI error can occur and not be seen by EEH because nothing
diff --git a/drivers/net/ethernet/sfc/efx.h b/drivers/net/ethernet/sfc/efx.h
index 8372da2..bdb30bb 100644
--- a/drivers/net/ethernet/sfc/efx.h
+++ b/drivers/net/ethernet/sfc/efx.h
@@ -124,6 +124,7 @@
extern int efx_reset(struct efx_nic *efx, enum reset_type method);
extern void efx_reset_down(struct efx_nic *efx, enum reset_type method);
extern int efx_reset_up(struct efx_nic *efx, enum reset_type method, bool ok);
+extern int efx_try_recovery(struct efx_nic *efx);
/* Global */
extern void efx_schedule_reset(struct efx_nic *efx, enum reset_type type);
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index 9a2914c..2dec48b 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -788,6 +788,7 @@
const struct efx_nic_type *type;
int legacy_irq;
bool legacy_irq_enabled;
+ bool eeh_disabled_legacy_irq;
struct workqueue_struct *workqueue;
char workqueue_name[16];
struct work_struct reset_work;
diff --git a/drivers/net/ethernet/sfc/nic.c b/drivers/net/ethernet/sfc/nic.c
index b0503cd..39432d3 100644
--- a/drivers/net/ethernet/sfc/nic.c
+++ b/drivers/net/ethernet/sfc/nic.c
@@ -1579,6 +1579,16 @@
efx_readd(efx, ®, FR_BZ_INT_ISR0);
queues = EFX_EXTRACT_DWORD(reg, 0, 31);
+ /* Legacy interrupts are disabled too late by the EEH kernel
+ * code. Disable them earlier.
+ * If an EEH error occurred, the read will have returned all ones.
+ */
+ if (EFX_DWORD_IS_ALL_ONES(reg) && efx_try_recovery(efx) &&
+ !efx->eeh_disabled_legacy_irq) {
+ disable_irq_nosync(efx->legacy_irq);
+ efx->eeh_disabled_legacy_irq = true;
+ }
+
/* Handle non-event-queue sources */
if (queues & (1U << efx->irq_level)) {
syserr = EFX_OWORD_FIELD(*int_ker, FSF_AZ_NET_IVEC_FATAL_INT);