accel/ivpu: Do not access HW registers after unbind

We should not access hardware after we unbind from the bus.

Use drm_dev_enter() / drm_dev_exit() to mark code sections where
hardware is accessed (and not already protected by other locks)
and drm_dev_unplug() to mark device is gone.

Fixes: 35b137630f08 ("accel/ivpu: Introduce a new DRM driver for Intel VPU")
Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230323125504.2586442-2-stanislaw.gruszka@linux.intel.com

diff --git a/drivers/accel/ivpu/ivpu_drv.c b/drivers/accel/ivpu/ivpu_drv.c
index 231f29b..ac06bbf 100644 (file)
--- a/drivers/accel/ivpu/ivpu_drv.c
+++ b/drivers/accel/ivpu/ivpu_drv.c
@@ -8,7 +8,6 @@
 #include <linux/pci.h>
 
 #include <drm/drm_accel.h>
-#include <drm/drm_drv.h>
 #include <drm/drm_file.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_ioctl.h>
@@ -118,6 +117,10 @@ static int ivpu_get_param_ioctl(struct drm_device *dev, void *data, struct drm_f
        struct pci_dev *pdev = to_pci_dev(vdev->drm.dev);
        struct drm_ivpu_param *args = data;
        int ret = 0;
+       int idx;
+
+       if (!drm_dev_enter(dev, &idx))
+               return -ENODEV;
 
        switch (args->param) {
        case DRM_IVPU_PARAM_DEVICE_ID:
@@ -171,6 +174,7 @@ static int ivpu_get_param_ioctl(struct drm_device *dev, void *data, struct drm_f
                break;
        }
 
+       drm_dev_exit(idx);
        return ret;
 }
 
@@ -622,7 +626,7 @@ static void ivpu_remove(struct pci_dev *pdev)
 {
        struct ivpu_device *vdev = pci_get_drvdata(pdev);
 
-       drm_dev_unregister(&vdev->drm);
+       drm_dev_unplug(&vdev->drm);
        ivpu_dev_fini(vdev);
 }
 

diff --git a/drivers/accel/ivpu/ivpu_drv.h b/drivers/accel/ivpu/ivpu_drv.h
index f47b496..1b2aa05 100644 (file)
--- a/drivers/accel/ivpu/ivpu_drv.h
+++ b/drivers/accel/ivpu/ivpu_drv.h
@@ -7,6 +7,7 @@
 #define __IVPU_DRV_H__
 
 #include <drm/drm_device.h>
+#include <drm/drm_drv.h>
 #include <drm/drm_managed.h>
 #include <drm/drm_mm.h>
 #include <drm/drm_print.h>

diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c
index 94068ae..910301f 100644 (file)
--- a/drivers/accel/ivpu/ivpu_job.c
+++ b/drivers/accel/ivpu/ivpu_job.c
@@ -489,12 +489,12 @@ unlock_reservations:
 
 int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 {
-       int ret = 0;
        struct ivpu_file_priv *file_priv = file->driver_priv;
        struct ivpu_device *vdev = file_priv->vdev;
        struct drm_ivpu_submit *params = data;
        struct ivpu_job *job;
        u32 *buf_handles;
+       int idx, ret;
 
        if (params->engine > DRM_IVPU_ENGINE_COPY)
                return -EINVAL;
@@ -523,6 +523,11 @@ int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
                goto free_handles;
        }
 
+       if (!drm_dev_enter(&vdev->drm, &idx)) {
+               ret = -ENODEV;
+               goto free_handles;
+       }
+
        ivpu_dbg(vdev, JOB, "Submit ioctl: ctx %u buf_count %u\n",
                 file_priv->ctx.id, params->buffer_count);
 
@@ -530,7 +535,7 @@ int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
        if (!job) {
                ivpu_err(vdev, "Failed to create job\n");
                ret = -ENOMEM;
-               goto free_handles;
+               goto dev_exit;
        }
 
        ret = ivpu_job_prepare_bos_for_submit(file, job, buf_handles, params->buffer_count,
@@ -548,6 +553,8 @@ int ivpu_submit_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 
 job_put:
        job_put(job);
+dev_exit:
+       drm_dev_exit(idx);
 free_handles:
        kfree(buf_handles);