habanalabs: fix resetting args in wait for CS IOCTL

In wait for CS IOCTL code, the driver resets the incoming args structure
before returning to the user, regardless of the return value of the
IOCTL.

In case the IOCTL returns EINTR, resetting the args will result in error
in case the userspace will repeat the ioctl call immediately (which is
the behavior in the hl-thunk userspace library).

The solution is to reset the args only if the driver returns success (0)
as a return value for the IOCTL.

Signed-off-by: Rajaravi Krishna Katta <rkatta@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

1 files changed, 19 insertions, 14 deletions

diff --git a/drivers/misc/habanalabs/common/command_submission.c b/drivers/misc/habanalabs/common/command_submission.c
index 91b57544f7c6..6dafff375f1c 100644
--- a/drivers/misc/habanalabs/common/command_submission.c
+++ b/drivers/misc/habanalabs/common/command_submission.c
@@ -2649,11 +2649,18 @@ put_ctx:
 free_seq_arr:
 	kfree(cs_seq_arr);
 
-	/* update output args */
-	memset(args, 0, sizeof(*args));
 	if (rc)
 		return rc;
 
+	if (mcs_data.wait_status == -ERESTARTSYS) {
+		dev_err_ratelimited(hdev->dev,
+				"user process got signal while waiting for Multi-CS\n");
+		return -EINTR;
+	}
+
+	/* update output args */
+	memset(args, 0, sizeof(*args));
+
 	if (mcs_data.completion_bitmap) {
 		args->out.status = HL_WAIT_CS_STATUS_COMPLETED;
 		args->out.cs_completion_map = mcs_data.completion_bitmap;
@@ -2667,8 +2674,6 @@ free_seq_arr:
 		/* update if some CS was gone */
 		if (mcs_data.timestamp)
 			args->out.flags |= HL_WAIT_CS_STATUS_FLAG_GONE;
-	} else if (mcs_data.wait_status == -ERESTARTSYS) {
-		args->out.status = HL_WAIT_CS_STATUS_INTERRUPTED;
 	} else {
 		args->out.status = HL_WAIT_CS_STATUS_BUSY;
 	}
@@ -2688,16 +2693,17 @@ static int hl_cs_wait_ioctl(struct hl_fpriv *hpriv, void *data)
 	rc = _hl_cs_wait_ioctl(hdev, hpriv->ctx, args->in.timeout_us, seq,
 				&status, &timestamp);
 
+	if (rc == -ERESTARTSYS) {
+		dev_err_ratelimited(hdev->dev,
+			"user process got signal while waiting for CS handle %llu\n",
+			seq);
+		return -EINTR;
+	}
+
 	memset(args, 0, sizeof(*args));
 
 	if (rc) {
-		if (rc == -ERESTARTSYS) {
-			dev_err_ratelimited(hdev->dev,
-				"user process got signal while waiting for CS handle %llu\n",
-				seq);
-			args->out.status = HL_WAIT_CS_STATUS_INTERRUPTED;
-			rc = -EINTR;
-		} else if (rc == -ETIMEDOUT) {
+		if (rc == -ETIMEDOUT) {
 			dev_err_ratelimited(hdev->dev,
 				"CS %llu has timed-out while user process is waiting for it\n",
 				seq);
@@ -2823,7 +2829,6 @@ wait_again:
 		dev_err_ratelimited(hdev->dev,
 			"user process got signal while waiting for interrupt ID %d\n",
 			interrupt->interrupt_id);
-		*status = HL_WAIT_CS_STATUS_INTERRUPTED;
 		rc = -EINTR;
 	} else {
 		*status = CS_WAIT_STATUS_BUSY;
@@ -2878,8 +2883,6 @@ static int hl_interrupt_wait_ioctl(struct hl_fpriv *hpriv, void *data)
 				args->in.interrupt_timeout_us, args->in.addr,
 				args->in.target, interrupt_offset, &status);
 
-	memset(args, 0, sizeof(*args));
-
 	if (rc) {
 		if (rc != -EINTR)
 			dev_err_ratelimited(hdev->dev,
@@ -2888,6 +2891,8 @@ static int hl_interrupt_wait_ioctl(struct hl_fpriv *hpriv, void *data)
 		return rc;
 	}
 
+	memset(args, 0, sizeof(*args));
+
 	switch (status) {
 	case CS_WAIT_STATUS_COMPLETED:
 		args->out.status = HL_WAIT_CS_STATUS_COMPLETED;