On 1/5/2024 4:22 AM, Jacek Lawrynowicz wrote:
Limit number of iterations in ivpu_mmu_irq_evtq_handler() and
ivpu_ipc_irq_handler().
"potential infinite loops" sounds like something that has not been
observed. Has a problem actually occurred?
Are you concerned that the FW is broken and spamming Linux with events?
Why a limit of 100 events? Seems arbitrary.
I suspect threaded irqs might be useful here, but it is hard to tell.
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
---
drivers/accel/ivpu/ivpu_ipc.c | 6 ++++++
drivers/accel/ivpu/ivpu_mmu.c | 21 +++++++++++++--------
2 files changed, 19 insertions(+), 8 deletions(-)
diff --git a/drivers/accel/ivpu/ivpu_ipc.c b/drivers/accel/ivpu/ivpu_ipc.c
index e86621f16f85..f69780248803 100644
--- a/drivers/accel/ivpu/ivpu_ipc.c
+++ b/drivers/accel/ivpu/ivpu_ipc.c
@@ -389,12 +389,18 @@ void ivpu_ipc_irq_handler(struct ivpu_device *vdev, bool *wake_thread)
unsigned long flags;
bool dispatched;
u32 vpu_addr;
+ int msg_count = 0;
/*
* Driver needs to purge all messages from IPC FIFO to clear IPC interrupt.
* Without purge IPC FIFO to 0 next IPC interrupts won't be generated.
*/
while (ivpu_hw_reg_ipc_rx_count_get(vdev)) {
+ if (++msg_count > IPC_MAX_RX_MSG) {
+ ivpu_pm_schedule_recovery(vdev);
+ return;
+ }
+
vpu_addr = ivpu_hw_reg_ipc_rx_addr_get(vdev);
if (vpu_addr == REG_IO_ERROR) {
ivpu_err_ratelimited(vdev, "Failed to read IPC rx addr register\n");
diff --git a/drivers/accel/ivpu/ivpu_mmu.c b/drivers/accel/ivpu/ivpu_mmu.c
index 1f813625aab3..c82929b0ae9d 100644
--- a/drivers/accel/ivpu/ivpu_mmu.c
+++ b/drivers/accel/ivpu/ivpu_mmu.c
@@ -236,6 +236,8 @@
#define IVPU_MMU_CERROR_ABT 0x2
#define IVPU_MMU_CERROR_ATC_INV_SYNC 0x3
+#define IVPU_MMU_MAX_EVENT_COUNT 100
+
static const char *ivpu_mmu_event_to_str(u32 cmd)
{
switch (cmd) {
@@ -887,7 +889,7 @@ static u32 *ivpu_mmu_get_event(struct ivpu_device *vdev)
void ivpu_mmu_irq_evtq_handler(struct ivpu_device *vdev)
{
- bool schedule_recovery = false;
+ int event_count = 0;
u32 *event;
u32 ssid;
@@ -895,16 +897,19 @@ void ivpu_mmu_irq_evtq_handler(struct ivpu_device *vdev)
while ((event = ivpu_mmu_get_event(vdev)) != NULL) {
ivpu_mmu_dump_event(vdev, event);
+ if (++event_count > IVPU_MMU_MAX_EVENT_COUNT) {
+ ivpu_pm_schedule_recovery(vdev);
+ return;
+ }
ssid = FIELD_GET(IVPU_MMU_EVT_SSID_MASK, event[0]);
- if (ssid == IVPU_GLOBAL_CONTEXT_MMU_SSID)
- schedule_recovery = true;
- else
- ivpu_mmu_user_context_mark_invalid(vdev, ssid);
- }
+ if (ssid == IVPU_GLOBAL_CONTEXT_MMU_SSID) {
+ ivpu_pm_schedule_recovery(vdev);
+ return;
+ }
- if (schedule_recovery)
- ivpu_pm_schedule_recovery(vdev);
+ ivpu_mmu_user_context_mark_invalid(vdev, ssid);
+ }
}
void ivpu_mmu_evtq_dump(struct ivpu_device *vdev)
