habanalabs: soft-reset device if context-switch fails

This patch fix a bug in the driver, where if the TPC or MME remains in
non-IDLE even after all the command submissions are done (due to user bug
or malicious user), then future command submissions will fail in the
context-switch stage and the driver will remain in "stuck" mode.

The fix is to do a soft-reset of the device in case the context-switch
fails, because the device should be IDLE during context-switch. If it is
not IDLE, then something is wrong and we should reset the compute engines.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Oded Gabbay 2019-02-28 10:46:21 +02:00 committed by Greg Kroah-Hartman
parent efaa281219
commit af5f7eea45
2 changed files with 10 additions and 8 deletions

View File

@ -622,13 +622,15 @@ int hl_cs_ioctl(struct hl_fpriv *hpriv, void *data)
"Failed to switch to context %d, rejecting CS! %d\n",
ctx->asid, rc);
/*
* If we timedout, we need to soft-reset because
* QMAN is probably stuck. However, we can't
* call to reset here directly because of
* deadlock, so need to do it at the very end
* of this function
* If we timedout, or if the device is not IDLE
* while we want to do context-switch (-EBUSY),
* we need to soft-reset because QMAN is
* probably stuck. However, we can't call to
* reset here directly because of deadlock, so
* need to do it at the very end of this
* function
*/
if (rc == -ETIMEDOUT)
if ((rc == -ETIMEDOUT) || (rc == -EBUSY))
need_soft_reset = true;
mutex_unlock(&hpriv->restore_phase_mutex);
goto out;
@ -706,7 +708,7 @@ int hl_cs_ioctl(struct hl_fpriv *hpriv, void *data)
args->out.seq = cs_seq;
}
if ((rc == -ETIMEDOUT) && (need_soft_reset))
if (((rc == -ETIMEDOUT) || (rc == -EBUSY)) && (need_soft_reset))
hl_device_reset(hdev, false, false);
return rc;

View File

@ -3138,7 +3138,7 @@ static int goya_send_job_on_qman0(struct hl_device *hdev, struct hl_cs_job *job)
if (!hdev->asic_funcs->is_device_idle(hdev)) {
dev_err_ratelimited(hdev->dev,
"Can't send KMD job on QMAN0 if device is not idle\n");
return -EFAULT;
return -EBUSY;
}
fence_ptr = hdev->asic_funcs->dma_pool_zalloc(hdev, 4, GFP_KERNEL,