stable.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* FAILED: patch "[PATCH] drm/tegra: fbdev: Remove offset into framebuffer memory" failed to apply to 6.18-stable tree
@ 2026-07-29 10:34 gregkh
  2026-07-31  2:41 ` [PATCH 6.18.y 1/2] drm/fb-helper: Allocate and release fb_info in single place Sasha Levin
  0 siblings, 1 reply; 3+ messages in thread
From: gregkh @ 2026-07-29 10:34 UTC (permalink / raw)
  To: tzimmermann, stable, treding; +Cc: stable


The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x a18b6e30ecd69096beda4a0c96d2570900c3879a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026072951-strategy-rage-af59@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a18b6e30ecd69096beda4a0c96d2570900c3879a Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann@suse.de>
Date: Tue, 21 Apr 2026 09:29:06 +0200
Subject: [PATCH] drm/tegra: fbdev: Remove offset into framebuffer memory

The screen_buffer field in struct fb_info contains the kernel address
of the first byte of framebuffer memory. Do not add the display offset.
This offset only describes scrolling during scanout.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: de2ba664c30f ("gpu: host1x: drm: Add memory manager and fb")
Cc: dri-devel@lists.freedesktop.org
Cc: linux-tegra@vger.kernel.org
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260421073646.144712-3-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/tegra/fbdev.c b/drivers/gpu/drm/tegra/fbdev.c
index 19e39fa54bfa..793849199783 100644
--- a/drivers/gpu/drm/tegra/fbdev.c
+++ b/drivers/gpu/drm/tegra/fbdev.c
@@ -76,7 +76,6 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	struct fb_info *info = helper->info;
 	unsigned int bytes_per_pixel;
 	struct drm_framebuffer *fb;
-	unsigned long offset;
 	struct tegra_bo *bo;
 	size_t size;
 	int err;
@@ -115,9 +114,6 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 
 	drm_fb_helper_fill_info(info, helper, sizes);
 
-	offset = info->var.xoffset * bytes_per_pixel +
-		 info->var.yoffset * fb->pitches[0];
-
 	if (bo->pages) {
 		bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
 				 pgprot_writecombine(PAGE_KERNEL));
@@ -129,9 +125,9 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	}
 
 	info->flags |= FBINFO_VIRTFB;
-	info->screen_buffer = bo->vaddr + offset;
+	info->screen_buffer = bo->vaddr;
 	info->screen_size = size;
-	info->fix.smem_start = (unsigned long)(bo->iova + offset);
+	info->fix.smem_start = (unsigned long)(bo->iova);
 	info->fix.smem_len = size;
 
 	return 0;


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH 6.18.y 1/2] drm/fb-helper: Allocate and release fb_info in single place
  2026-07-29 10:34 FAILED: patch "[PATCH] drm/tegra: fbdev: Remove offset into framebuffer memory" failed to apply to 6.18-stable tree gregkh
@ 2026-07-31  2:41 ` Sasha Levin
  2026-07-31  2:41   ` [PATCH 6.18.y 2/2] drm/tegra: fbdev: Remove offset into framebuffer memory Sasha Levin
  0 siblings, 1 reply; 3+ messages in thread
From: Sasha Levin @ 2026-07-31  2:41 UTC (permalink / raw)
  To: stable
  Cc: Thomas Zimmermann, Christian König, Dmitry Baryshkov,
	Javier Martinez Canillas, Sasha Levin

From: Thomas Zimmermann <tzimmermann@suse.de>

[ Upstream commit 63c971af40365ee706c7e24f6a7900d693518f09 ]

Move the calls to drm_fb_helper_alloc_info() from drivers into a
single place in fbdev helpers. Allocates struct fb_info for a new
framebuffer device. Then call drm_fb_helper_single_fb_probe() to
create an fbdev screen buffer. Also release the instance on errors
by calling drm_fb_helper_release_info().

Simplifies the code and fixes the error cleanup for some of the
drivers.

Regular release of the struct fb_info instance still happens in
drm_fb_helper_fini() as before.

v2:
- remove error rollback in driver implementations (kernel test robot)
- initialize info in TTM implementation (kernel test robot)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Christian König <christian.koenig@amd.com> # radeon
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> # msm
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patch.msgid.link/20251027081245.80262-1-tzimmermann@suse.de
Stable-dep-of: a18b6e30ecd6 ("drm/tegra: fbdev: Remove offset into framebuffer memory")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/armada/armada_fbdev.c      | 12 +------
 drivers/gpu/drm/drm_fb_helper.c            | 39 +++++++---------------
 drivers/gpu/drm/drm_fbdev_dma.c            | 12 ++-----
 drivers/gpu/drm/drm_fbdev_shmem.c          | 12 ++-----
 drivers/gpu/drm/drm_fbdev_ttm.c            | 12 ++-----
 drivers/gpu/drm/exynos/exynos_drm_fbdev.c  |  9 +----
 drivers/gpu/drm/gma500/fbdev.c             | 12 +------
 drivers/gpu/drm/i915/display/intel_fbdev.c |  9 +----
 drivers/gpu/drm/msm/msm_fbdev.c            |  9 +----
 drivers/gpu/drm/omapdrm/omap_fbdev.c       |  9 +----
 drivers/gpu/drm/radeon/radeon_fbdev.c      | 13 +-------
 drivers/gpu/drm/tegra/fbdev.c              |  9 +----
 include/drm/drm_fb_helper.h                | 12 -------
 13 files changed, 26 insertions(+), 143 deletions(-)

diff --git a/drivers/gpu/drm/armada/armada_fbdev.c b/drivers/gpu/drm/armada/armada_fbdev.c
index cb53cc91bafb..4a8c432e311e 100644
--- a/drivers/gpu/drm/armada/armada_fbdev.c
+++ b/drivers/gpu/drm/armada/armada_fbdev.c
@@ -45,10 +45,10 @@ int armada_fbdev_driver_fbdev_probe(struct drm_fb_helper *fbh,
 				    struct drm_fb_helper_surface_size *sizes)
 {
 	struct drm_device *dev = fbh->dev;
+	struct fb_info *info = fbh->info;
 	struct drm_mode_fb_cmd2 mode;
 	struct armada_framebuffer *dfb;
 	struct armada_gem_object *obj;
-	struct fb_info *info;
 	int size, ret;
 	void *ptr;
 
@@ -92,12 +92,6 @@ int armada_fbdev_driver_fbdev_probe(struct drm_fb_helper *fbh,
 	if (IS_ERR(dfb))
 		return PTR_ERR(dfb);
 
-	info = drm_fb_helper_alloc_info(fbh);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_fballoc;
-	}
-
 	info->fbops = &armada_fb_ops;
 	info->fix.smem_start = obj->phys_addr;
 	info->fix.smem_len = obj->obj.size;
@@ -113,8 +107,4 @@ int armada_fbdev_driver_fbdev_probe(struct drm_fb_helper *fbh,
 		(unsigned long long)obj->phys_addr);
 
 	return 0;
-
- err_fballoc:
-	dfb->fb.funcs->destroy(&dfb->fb);
-	return ret;
 }
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 0b3ee008523d..18a00de2ec1f 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -489,20 +489,7 @@ int drm_fb_helper_init(struct drm_device *dev,
 }
 EXPORT_SYMBOL(drm_fb_helper_init);
 
-/**
- * drm_fb_helper_alloc_info - allocate fb_info and some of its members
- * @fb_helper: driver-allocated fbdev helper
- *
- * A helper to alloc fb_info and the member cmap. Called by the driver
- * within the struct &drm_driver.fbdev_probe callback function. Drivers do
- * not need to release the allocated fb_info structure themselves, this is
- * automatically done when calling drm_fb_helper_fini().
- *
- * RETURNS:
- * fb_info pointer if things went okay, pointer containing error code
- * otherwise
- */
-struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
+static struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
 {
 	struct device *dev = fb_helper->dev->dev;
 	struct fb_info *info;
@@ -529,17 +516,8 @@ struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
 	framebuffer_release(info);
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL(drm_fb_helper_alloc_info);
 
-/**
- * drm_fb_helper_release_info - release fb_info and its members
- * @fb_helper: driver-allocated fbdev helper
- *
- * A helper to release fb_info and the member cmap.  Drivers do not
- * need to release the allocated fb_info structure themselves, this is
- * automatically done when calling drm_fb_helper_fini().
- */
-void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
+static void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
 {
 	struct fb_info *info = fb_helper->info;
 
@@ -552,7 +530,6 @@ void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
 		fb_dealloc_cmap(&info->cmap);
 	framebuffer_release(info);
 }
-EXPORT_SYMBOL(drm_fb_helper_release_info);
 
 /**
  * drm_fb_helper_unregister_info - unregister fb_info framebuffer device
@@ -1813,6 +1790,11 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper)
 	height = dev->mode_config.max_height;
 
 	drm_client_modeset_probe(&fb_helper->client, width, height);
+
+	info = drm_fb_helper_alloc_info(fb_helper);
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+
 	ret = drm_fb_helper_single_fb_probe(fb_helper);
 	if (ret < 0) {
 		if (ret == -EAGAIN) {
@@ -1821,13 +1803,12 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper)
 		}
 		mutex_unlock(&fb_helper->lock);
 
-		return ret;
+		goto err_drm_fb_helper_release_info;
 	}
 	drm_setup_crtcs_fb(fb_helper);
 
 	fb_helper->deferred_setup = false;
 
-	info = fb_helper->info;
 	info->var.pixclock = 0;
 
 	/* Need to drop locks to avoid recursive deadlock in
@@ -1850,6 +1831,10 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper)
 	mutex_unlock(&kernel_fb_helper_lock);
 
 	return 0;
+
+err_drm_fb_helper_release_info:
+	drm_fb_helper_release_info(fb_helper);
+	return ret;
 }
 
 /**
diff --git a/drivers/gpu/drm/drm_fbdev_dma.c b/drivers/gpu/drm/drm_fbdev_dma.c
index 8bd626ef16c7..7b77c801a63a 100644
--- a/drivers/gpu/drm/drm_fbdev_dma.c
+++ b/drivers/gpu/drm/drm_fbdev_dma.c
@@ -272,9 +272,9 @@ int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 {
 	struct drm_client_dev *client = &fb_helper->client;
 	struct drm_device *dev = fb_helper->dev;
+	struct fb_info *info = fb_helper->info;
 	struct drm_client_buffer *buffer;
 	struct drm_framebuffer *fb;
-	struct fb_info *info;
 	u32 format;
 	struct iosys_map map;
 	int ret;
@@ -304,12 +304,6 @@ int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	fb_helper->buffer = buffer;
 	fb_helper->fb = fb;
 
-	info = drm_fb_helper_alloc_info(fb_helper);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_drm_client_buffer_vunmap;
-	}
-
 	drm_fb_helper_fill_info(info, fb_helper, sizes);
 
 	if (fb->funcs->dirty)
@@ -317,12 +311,10 @@ int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	else
 		ret = drm_fbdev_dma_driver_fbdev_probe_tail(fb_helper, sizes);
 	if (ret)
-		goto err_drm_fb_helper_release_info;
+		goto err_drm_client_buffer_vunmap;
 
 	return 0;
 
-err_drm_fb_helper_release_info:
-	drm_fb_helper_release_info(fb_helper);
 err_drm_client_buffer_vunmap:
 	fb_helper->fb = NULL;
 	fb_helper->buffer = NULL;
diff --git a/drivers/gpu/drm/drm_fbdev_shmem.c b/drivers/gpu/drm/drm_fbdev_shmem.c
index 1e827bf8b815..77f350700818 100644
--- a/drivers/gpu/drm/drm_fbdev_shmem.c
+++ b/drivers/gpu/drm/drm_fbdev_shmem.c
@@ -136,10 +136,10 @@ int drm_fbdev_shmem_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 {
 	struct drm_client_dev *client = &fb_helper->client;
 	struct drm_device *dev = fb_helper->dev;
+	struct fb_info *info = fb_helper->info;
 	struct drm_client_buffer *buffer;
 	struct drm_gem_shmem_object *shmem;
 	struct drm_framebuffer *fb;
-	struct fb_info *info;
 	u32 format;
 	struct iosys_map map;
 	int ret;
@@ -169,12 +169,6 @@ int drm_fbdev_shmem_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	fb_helper->buffer = buffer;
 	fb_helper->fb = fb;
 
-	info = drm_fb_helper_alloc_info(fb_helper);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_drm_client_buffer_vunmap;
-	}
-
 	drm_fb_helper_fill_info(info, fb_helper, sizes);
 
 	info->fbops = &drm_fbdev_shmem_fb_ops;
@@ -195,12 +189,10 @@ int drm_fbdev_shmem_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	info->fbdefio = &fb_helper->fbdefio;
 	ret = fb_deferred_io_init(info);
 	if (ret)
-		goto err_drm_fb_helper_release_info;
+		goto err_drm_client_buffer_vunmap;
 
 	return 0;
 
-err_drm_fb_helper_release_info:
-	drm_fb_helper_release_info(fb_helper);
 err_drm_client_buffer_vunmap:
 	fb_helper->fb = NULL;
 	fb_helper->buffer = NULL;
diff --git a/drivers/gpu/drm/drm_fbdev_ttm.c b/drivers/gpu/drm/drm_fbdev_ttm.c
index 85feb55bba11..1ba258f3c854 100644
--- a/drivers/gpu/drm/drm_fbdev_ttm.c
+++ b/drivers/gpu/drm/drm_fbdev_ttm.c
@@ -176,8 +176,8 @@ int drm_fbdev_ttm_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 {
 	struct drm_client_dev *client = &fb_helper->client;
 	struct drm_device *dev = fb_helper->dev;
+	struct fb_info *info = fb_helper->info;
 	struct drm_client_buffer *buffer;
-	struct fb_info *info;
 	size_t screen_size;
 	void *screen_buffer;
 	u32 format;
@@ -205,12 +205,6 @@ int drm_fbdev_ttm_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 		goto err_drm_client_framebuffer_delete;
 	}
 
-	info = drm_fb_helper_alloc_info(fb_helper);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_vfree;
-	}
-
 	drm_fb_helper_fill_info(info, fb_helper, sizes);
 
 	info->fbops = &drm_fbdev_ttm_fb_ops;
@@ -227,12 +221,10 @@ int drm_fbdev_ttm_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	info->fbdefio = &fb_helper->fbdefio;
 	ret = fb_deferred_io_init(info);
 	if (ret)
-		goto err_drm_fb_helper_release_info;
+		goto err_vfree;
 
 	return 0;
 
-err_drm_fb_helper_release_info:
-	drm_fb_helper_release_info(fb_helper);
 err_vfree:
 	vfree(screen_buffer);
 err_drm_client_framebuffer_delete:
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index 93de25b77e68..b0bd0697910e 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -59,18 +59,11 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
 				   struct drm_fb_helper_surface_size *sizes,
 				   struct exynos_drm_gem *exynos_gem)
 {
-	struct fb_info *fbi;
+	struct fb_info *fbi = helper->info;
 	struct drm_framebuffer *fb = helper->fb;
 	unsigned int size = fb->width * fb->height * fb->format->cpp[0];
 	unsigned long offset;
 
-	fbi = drm_fb_helper_alloc_info(helper);
-	if (IS_ERR(fbi)) {
-		DRM_DEV_ERROR(to_dma_dev(helper->dev),
-			      "failed to allocate fb info.\n");
-		return PTR_ERR(fbi);
-	}
-
 	fbi->fbops = &exynos_drm_fb_ops;
 
 	drm_fb_helper_fill_info(fbi, helper, sizes);
diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
index a6af21514cff..dacc118b1242 100644
--- a/drivers/gpu/drm/gma500/fbdev.c
+++ b/drivers/gpu/drm/gma500/fbdev.c
@@ -111,7 +111,7 @@ int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	struct drm_device *dev = fb_helper->dev;
 	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
-	struct fb_info *info;
+	struct fb_info *info = fb_helper->info;
 	struct drm_framebuffer *fb;
 	struct drm_mode_fb_cmd2 mode_cmd = { };
 	int size;
@@ -170,12 +170,6 @@ int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	fb_helper->funcs = &psb_fbdev_fb_helper_funcs;
 	fb_helper->fb = fb;
 
-	info = drm_fb_helper_alloc_info(fb_helper);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_drm_framebuffer_unregister_private;
-	}
-
 	info->fbops = &psb_fbdev_fb_ops;
 
 	/* Accessed stolen memory directly */
@@ -199,10 +193,6 @@ int psb_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 
 	return 0;
 
-err_drm_framebuffer_unregister_private:
-	drm_framebuffer_unregister_private(fb);
-	drm_framebuffer_cleanup(fb);
-	kfree(fb);
 err_drm_gem_object_put:
 	drm_gem_object_put(obj);
 	return ret;
diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
index 7daf72b69bae..a42b0943ed95 100644
--- a/drivers/gpu/drm/i915/display/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
@@ -242,8 +242,8 @@ int intel_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	struct intel_display *display = to_intel_display(helper->dev);
 	struct intel_fbdev *ifbdev = to_intel_fbdev(helper);
 	struct intel_framebuffer *fb = ifbdev->fb;
+	struct fb_info *info = helper->info;
 	struct ref_tracker *wakeref;
-	struct fb_info *info;
 	struct i915_vma *vma;
 	unsigned long flags = 0;
 	bool prealloc = false;
@@ -296,13 +296,6 @@ int intel_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 		goto out_unlock;
 	}
 
-	info = drm_fb_helper_alloc_info(helper);
-	if (IS_ERR(info)) {
-		drm_err(display->drm, "Failed to allocate fb_info (%pe)\n", info);
-		ret = PTR_ERR(info);
-		goto out_unpin;
-	}
-
 	helper->funcs = &intel_fb_helper_funcs;
 	helper->fb = &fb->base;
 
diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index b5969374d53f..d86c89d03f4b 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -93,9 +93,9 @@ int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 {
 	struct drm_device *dev = helper->dev;
 	struct msm_drm_private *priv = dev->dev_private;
+	struct fb_info *fbi = helper->info;
 	struct drm_framebuffer *fb = NULL;
 	struct drm_gem_object *bo;
-	struct fb_info *fbi = NULL;
 	uint64_t paddr;
 	uint32_t format;
 	int ret, pitch;
@@ -128,13 +128,6 @@ int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 		goto fail;
 	}
 
-	fbi = drm_fb_helper_alloc_info(helper);
-	if (IS_ERR(fbi)) {
-		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
-		ret = PTR_ERR(fbi);
-		goto fail;
-	}
-
 	DBG("fbi=%p, dev=%p", fbi, dev);
 
 	helper->funcs = &msm_fbdev_helper_funcs;
diff --git a/drivers/gpu/drm/omapdrm/omap_fbdev.c b/drivers/gpu/drm/omapdrm/omap_fbdev.c
index 948af7ec1130..2b435c05bdb1 100644
--- a/drivers/gpu/drm/omapdrm/omap_fbdev.c
+++ b/drivers/gpu/drm/omapdrm/omap_fbdev.c
@@ -155,9 +155,9 @@ int omap_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	struct drm_device *dev = helper->dev;
 	struct omap_drm_private *priv = dev->dev_private;
 	struct omap_fbdev *fbdev = priv->fbdev;
+	struct fb_info *fbi = helper->info;
 	struct drm_framebuffer *fb = NULL;
 	union omap_gem_size gsize;
-	struct fb_info *fbi = NULL;
 	struct drm_mode_fb_cmd2 mode_cmd = {0};
 	struct drm_gem_object *bo;
 	dma_addr_t dma_addr;
@@ -226,13 +226,6 @@ int omap_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 		goto fail;
 	}
 
-	fbi = drm_fb_helper_alloc_info(helper);
-	if (IS_ERR(fbi)) {
-		dev_err(dev->dev, "failed to allocate fb info\n");
-		ret = PTR_ERR(fbi);
-		goto fail;
-	}
-
 	DBG("fbi=%p, dev=%p", fbi, dev);
 
 	helper->funcs = &omap_fbdev_helper_funcs;
diff --git a/drivers/gpu/drm/radeon/radeon_fbdev.c b/drivers/gpu/drm/radeon/radeon_fbdev.c
index dc81b0c2dbff..d5c621d48e20 100644
--- a/drivers/gpu/drm/radeon/radeon_fbdev.c
+++ b/drivers/gpu/drm/radeon/radeon_fbdev.c
@@ -206,7 +206,7 @@ int radeon_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	struct radeon_device *rdev = fb_helper->dev->dev_private;
 	const struct drm_format_info *format_info;
 	struct drm_mode_fb_cmd2 mode_cmd = { };
-	struct fb_info *info;
+	struct fb_info *info = fb_helper->info;
 	struct drm_gem_object *gobj;
 	struct radeon_bo *rbo;
 	struct drm_framebuffer *fb;
@@ -247,13 +247,6 @@ int radeon_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 	fb_helper->funcs = &radeon_fbdev_fb_helper_funcs;
 	fb_helper->fb = fb;
 
-	/* okay we have an object now allocate the framebuffer */
-	info = drm_fb_helper_alloc_info(fb_helper);
-	if (IS_ERR(info)) {
-		ret = PTR_ERR(info);
-		goto err_drm_framebuffer_unregister_private;
-	}
-
 	info->fbops = &radeon_fbdev_fb_ops;
 
 	/* radeon resume is fragile and needs a vt switch to help it along */
@@ -279,10 +272,6 @@ int radeon_fbdev_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 
 	return 0;
 
-err_drm_framebuffer_unregister_private:
-	fb_helper->fb = NULL;
-	drm_framebuffer_unregister_private(fb);
-	drm_framebuffer_cleanup(fb);
 err_kfree:
 	kfree(fb);
 err_radeon_fbdev_destroy_pinned_object:
diff --git a/drivers/gpu/drm/tegra/fbdev.c b/drivers/gpu/drm/tegra/fbdev.c
index 1b70f5e164af..ba0971ec34b5 100644
--- a/drivers/gpu/drm/tegra/fbdev.c
+++ b/drivers/gpu/drm/tegra/fbdev.c
@@ -75,10 +75,10 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	struct tegra_drm *tegra = helper->dev->dev_private;
 	struct drm_device *drm = helper->dev;
 	struct drm_mode_fb_cmd2 cmd = { 0 };
+	struct fb_info *info = helper->info;
 	unsigned int bytes_per_pixel;
 	struct drm_framebuffer *fb;
 	unsigned long offset;
-	struct fb_info *info;
 	struct tegra_bo *bo;
 	size_t size;
 	int err;
@@ -99,13 +99,6 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	if (IS_ERR(bo))
 		return PTR_ERR(bo);
 
-	info = drm_fb_helper_alloc_info(helper);
-	if (IS_ERR(info)) {
-		dev_err(drm->dev, "failed to allocate framebuffer info\n");
-		drm_gem_object_put(&bo->gem);
-		return PTR_ERR(info);
-	}
-
 	fb = tegra_fb_alloc(drm,
 			    drm_get_format_info(drm, cmd.pixel_format, cmd.modifier[0]),
 			    &cmd, &bo, 1);
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index c1d38d54a112..2faf8aaf98dc 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -256,8 +256,6 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 
 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
 
-struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper);
-void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper);
 void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
 void drm_fb_helper_fill_info(struct fb_info *info,
 			     struct drm_fb_helper *fb_helper,
@@ -340,16 +338,6 @@ drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 	return 0;
 }
 
-static inline struct fb_info *
-drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
-{
-	return NULL;
-}
-
-static inline void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
-{
-}
-
 static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
 {
 }
-- 
2.53.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH 6.18.y 2/2] drm/tegra: fbdev: Remove offset into framebuffer memory
  2026-07-31  2:41 ` [PATCH 6.18.y 1/2] drm/fb-helper: Allocate and release fb_info in single place Sasha Levin
@ 2026-07-31  2:41   ` Sasha Levin
  0 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2026-07-31  2:41 UTC (permalink / raw)
  To: stable
  Cc: Thomas Zimmermann, dri-devel, linux-tegra, Thierry Reding,
	Sasha Levin

From: Thomas Zimmermann <tzimmermann@suse.de>

[ Upstream commit a18b6e30ecd69096beda4a0c96d2570900c3879a ]

The screen_buffer field in struct fb_info contains the kernel address
of the first byte of framebuffer memory. Do not add the display offset.
This offset only describes scrolling during scanout.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: de2ba664c30f ("gpu: host1x: drm: Add memory manager and fb")
Cc: dri-devel@lists.freedesktop.org
Cc: linux-tegra@vger.kernel.org
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260421073646.144712-3-tzimmermann@suse.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/tegra/fbdev.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/tegra/fbdev.c b/drivers/gpu/drm/tegra/fbdev.c
index ba0971ec34b5..d4ef5d5e4264 100644
--- a/drivers/gpu/drm/tegra/fbdev.c
+++ b/drivers/gpu/drm/tegra/fbdev.c
@@ -78,7 +78,6 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	struct fb_info *info = helper->info;
 	unsigned int bytes_per_pixel;
 	struct drm_framebuffer *fb;
-	unsigned long offset;
 	struct tegra_bo *bo;
 	size_t size;
 	int err;
@@ -118,9 +117,6 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 
 	drm_fb_helper_fill_info(info, helper, sizes);
 
-	offset = info->var.xoffset * bytes_per_pixel +
-		 info->var.yoffset * fb->pitches[0];
-
 	if (bo->pages) {
 		bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
 				 pgprot_writecombine(PAGE_KERNEL));
@@ -132,9 +128,9 @@ int tegra_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	}
 
 	info->flags |= FBINFO_VIRTFB;
-	info->screen_buffer = bo->vaddr + offset;
+	info->screen_buffer = bo->vaddr;
 	info->screen_size = size;
-	info->fix.smem_start = (unsigned long)(bo->iova + offset);
+	info->fix.smem_start = (unsigned long)(bo->iova);
 	info->fix.smem_len = size;
 
 	return 0;
-- 
2.53.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2026-07-31  2:41 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-07-29 10:34 FAILED: patch "[PATCH] drm/tegra: fbdev: Remove offset into framebuffer memory" failed to apply to 6.18-stable tree gregkh
2026-07-31  2:41 ` [PATCH 6.18.y 1/2] drm/fb-helper: Allocate and release fb_info in single place Sasha Levin
2026-07-31  2:41   ` [PATCH 6.18.y 2/2] drm/tegra: fbdev: Remove offset into framebuffer memory Sasha Levin

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).