On 4/19/2024 7:33 PM, Dmitry Baryshkov wrote:
Since commit 3c74682637e6 ("drm/msm/mdp4: move resource allocation to
the _probe function") the mdp4_kms data is allocated during probe. It is
an error to destroy it during mdp4_kms_init(), as the data is still
referenced by the drivers's data and can be used later in case of probe
deferral.
mdp4_destroy() currently detaches mmu, calls msm_kms_destroy() which destroys pending timers and releases refcount on the aspace.
It does not touch the mdp4_kms as that one is devm managed.In the comment https://patchwork.freedesktop.org/patch/590411/?series=132664&rev=1#comment_1074306, we had discussed that the last component's reprobe attempt is affected (which is not dpu or mdp4 or mdp5 right? )
If it was an interface (such as DSI OR DP), is it the aspace detach which is causing the crash?
Another note is, mdp5 needs the same fix in that case. dpu_kms_init() looks fine.
Fixes: 3c74682637e6 ("drm/msm/mdp4: move resource allocation to the _probe function") Signed-off-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> --- drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c index 4ba1cb74ad76..4c5f72b7e0e5 100644 --- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c +++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c @@ -392,7 +392,7 @@ static int mdp4_kms_init(struct drm_device *dev) ret = mdp_kms_init(&mdp4_kms->base, &kms_funcs); if (ret) { DRM_DEV_ERROR(dev->dev, "failed to init kms\n"); - goto fail; + return ret; }kms = priv->kms;@@ -403,7 +403,7 @@ static int mdp4_kms_init(struct drm_device *dev) ret = regulator_enable(mdp4_kms->vdd); if (ret) { DRM_DEV_ERROR(dev->dev, "failed to enable regulator vdd: %d\n", ret); - goto fail; + return ret; } }@@ -414,8 +414,7 @@ static int mdp4_kms_init(struct drm_device *dev)if (major != 4) { DRM_DEV_ERROR(dev->dev, "unexpected MDP version: v%d.%d\n", major, minor); - ret = -ENXIO; - goto fail; + return -ENXIO; }mdp4_kms->rev = minor;@@ -423,8 +422,7 @@ static int mdp4_kms_init(struct drm_device *dev) if (mdp4_kms->rev >= 2) { if (!mdp4_kms->lut_clk) { DRM_DEV_ERROR(dev->dev, "failed to get lut_clk\n"); - ret = -ENODEV; - goto fail; + return -ENODEV; } clk_set_rate(mdp4_kms->lut_clk, max_clk); } @@ -445,8 +443,7 @@ static int mdp4_kms_init(struct drm_device *dev)mmu = msm_iommu_new(&pdev->dev, 0);if (IS_ERR(mmu)) { - ret = PTR_ERR(mmu); - goto fail; + return PTR_ERR(mmu); } else if (!mmu) { DRM_DEV_INFO(dev->dev, "no iommu, fallback to phys " "contig buffers for scanout\n"); @@ -458,8 +455,7 @@ static int mdp4_kms_init(struct drm_device *dev) if (IS_ERR(aspace)) { if (!IS_ERR(mmu)) mmu->funcs->destroy(mmu); - ret = PTR_ERR(aspace); - goto fail; + return PTR_ERR(aspace); }kms->aspace = aspace;@@ -468,7 +464,7 @@ static int mdp4_kms_init(struct drm_device *dev) ret = modeset_init(mdp4_kms); if (ret) { DRM_DEV_ERROR(dev->dev, "modeset_init failed: %d\n", ret); - goto fail; + return ret; }mdp4_kms->blank_cursor_bo = msm_gem_new(dev, SZ_16K, MSM_BO_WC | MSM_BO_SCANOUT);@@ -476,14 +472,14 @@ static int mdp4_kms_init(struct drm_device *dev) ret = PTR_ERR(mdp4_kms->blank_cursor_bo); DRM_DEV_ERROR(dev->dev, "could not allocate blank-cursor bo: %d\n", ret); mdp4_kms->blank_cursor_bo = NULL; - goto fail; + return ret; }ret = msm_gem_get_and_pin_iova(mdp4_kms->blank_cursor_bo, kms->aspace,&mdp4_kms->blank_cursor_iova); if (ret) { DRM_DEV_ERROR(dev->dev, "could not pin blank-cursor bo: %d\n", ret); - goto fail; + return ret; }dev->mode_config.min_width = 0;@@ -492,12 +488,6 @@ static int mdp4_kms_init(struct drm_device *dev) dev->mode_config.max_height = 2048;return 0;- -fail: - if (kms) - mdp4_destroy(kms); - - return ret; }static const struct dev_pm_ops mdp4_pm_ops = {
