There is a (dubious?) lost irq workaround in sci_controller_isr() that
effectively nullifies attempts to disable interrupts. Until the
workaround can be re-evaluated add some infrastructure to prevent the
interrupt handler from inadvertantly re-enabling interrupts.
The failure mode was interrupts continuing to run after the driver had
been removed and its iomappings torn down.
Reported-by: Jacek Danecki <jacek.danecki@xxxxxxxxx>
Tested-by: Jacek Danecki <jacek.danecki@xxxxxxxxx>
[richard: clear remaining interrupts at the end of reset]
Acked-by: Richard Boyd <richard.g.boyd@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/scsi/isci/host.c | 39 ++++++++++++++++++++++++++-------------
drivers/scsi/isci/host.h | 1 +
2 files changed, 27 insertions(+), 13 deletions(-)
diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c
index 577a836..5832b13 100644
--- a/drivers/scsi/isci/host.c
+++ b/drivers/scsi/isci/host.c
@@ -192,22 +192,27 @@ static bool sci_controller_completion_queue_has_entries(struct isci_host *ihost)
static bool sci_controller_isr(struct isci_host *ihost)
{
- if (sci_controller_completion_queue_has_entries(ihost)) {
+ if (sci_controller_completion_queue_has_entries(ihost))
return true;
- } else {
- /*
- * we have a spurious interrupt it could be that we have already
- * emptied the completion queue from a previous interrupt */
- writel(SMU_ISR_COMPLETION, &ihost->smu_registers->interrupt_status);
- /*
- * There is a race in the hardware that could cause us not to be notified
- * of an interrupt completion if we do not take this step. We will mask
- * then unmask the interrupts so if there is another interrupt pending
- * the clearing of the interrupt source we get the next interrupt message. */
+ /* we have a spurious interrupt it could be that we have already
+ * emptied the completion queue from a previous interrupt
+ * FIXME: really!?
+ */
+ writel(SMU_ISR_COMPLETION, &ihost->smu_registers->interrupt_status);
+
+ /* There is a race in the hardware that could cause us not to be
+ * notified of an interrupt completion if we do not take this
+ * step. We will mask then unmask the interrupts so if there is
+ * another interrupt pending the clearing of the interrupt
+ * source we get the next interrupt message.
+ */
+ spin_lock(&ihost->scic_lock);
+ if (test_bit(IHOST_IRQ_ENABLED, &ihost->flags)) {
writel(0xFF000000, &ihost->smu_registers->interrupt_mask);
writel(0, &ihost->smu_registers->interrupt_mask);
}
+ spin_unlock(&ihost->scic_lock);
return false;
}
@@ -698,14 +703,15 @@ static u32 sci_controller_get_suggested_start_timeout(struct isci_host *ihost)
static void sci_controller_enable_interrupts(struct isci_host *ihost)
{
- BUG_ON(ihost->smu_registers == NULL);
+ set_bit(IHOST_IRQ_ENABLED, &ihost->flags);
writel(0, &ihost->smu_registers->interrupt_mask);
}
void sci_controller_disable_interrupts(struct isci_host *ihost)
{
- BUG_ON(ihost->smu_registers == NULL);
+ clear_bit(IHOST_IRQ_ENABLED, &ihost->flags);
writel(0xffffffff, &ihost->smu_registers->interrupt_mask);
+ readl(&ihost->smu_registers->interrupt_mask); /* flush */
}
static void sci_controller_enable_port_task_scheduler(struct isci_host *ihost)
@@ -1318,7 +1324,9 @@ void isci_host_deinit(struct isci_host *ihost)
*/
writel(0, &ihost->scu_registers->peg0.sgpio.interface_control);
+ spin_lock_irq(&ihost->scic_lock);
sci_controller_reset(ihost);
+ spin_unlock_irq(&ihost->scic_lock);
/* Cancel any/all outstanding port timers */
for (i = 0; i < ihost->logical_port_entries; i++) {
@@ -1605,6 +1613,9 @@ static void sci_controller_reset_hardware(struct isci_host *ihost)
/* The write to the UFQGP clears the UFQPR */
writel(0, &ihost->scu_registers->sdma.unsolicited_frame_get_pointer);
+
+ /* clear all interrupts */
+ writel(~SMU_INTERRUPT_STATUS_RESERVED_MASK, &ihost->smu_registers->interrupt_status);
}
static void sci_controller_resetting_state_enter(struct sci_base_state_machine *sm)
@@ -2391,7 +2402,9 @@ int isci_host_init(struct isci_host *ihost)
int i, err;
enum sci_status status;
+ spin_lock_irq(&ihost->scic_lock);
status = sci_controller_construct(ihost, scu_base(ihost), smu_base(ihost));
+ spin_unlock_irq(&ihost->scic_lock);
if (status != SCI_SUCCESS) {
dev_err(&ihost->pdev->dev,
"%s: sci_controller_construct failed - status = %x\n",
diff --git a/drivers/scsi/isci/host.h b/drivers/scsi/isci/host.h
index 9dc910b..9701c1d 100644
--- a/drivers/scsi/isci/host.h
+++ b/drivers/scsi/isci/host.h
@@ -200,6 +200,7 @@ struct isci_host {
struct pci_dev *pdev;
#define IHOST_START_PENDING 0
#define IHOST_STOP_PENDING 1
+ #define IHOST_IRQ_ENABLED 2
unsigned long flags;
wait_queue_head_t eventq;
struct Scsi_Host *shost;
--
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