Attachment 779797 Details for Bug 1101822

[patch] drm/cirrus: Use drm_framebuffer_put to avoid kernel oops in clean-up (SLE12-SP3) (v2)

0001-drm-cirrus-Use-drm_framebuffer_put-to-avoid-kernel-o.patch (text/plain), 5.39 KB, created by Thomas Zimmermann on 2018-08-15 14:14:54 UTC

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Creator: Thomas Zimmermann

Created: 2018-08-15 14:14:54 UTC

Size: 5.39 KB

patch

obsolete

>From cd88ee3d68f305c27018820adaaf3050b6e134b1 Mon Sep 17 00:00:00 2001
>From: Thomas Zimmermann <tzimmermann@suse.de>
>Date: Fri, 20 Jul 2018 12:48:02 +0200
>Subject: drm/cirrus: Use drm_framebuffer_put to avoid kernel oops in clean-up
>References: bsc#1101822
>Git-commit: abf7b30d7f61d981bfcca65d1e8331b27021b475
>Git-repo: git://anongit.freedesktop.org/drm/drm-misc
>Patch-mainline: Queued for upstream in drm-misc-next
>
>In the Cirrus driver, the regular clean-up code also performs the clean-up
>of a failed initialization. If the fbdev's framebuffer was not initialized,
>the clean-up will fail within drm_framebuffer_unregister_private. Booting
>with cirrus.bpp=16 triggers this bug.
>
>The framebuffer is currently stored directly within struct cirrus_fbdev. To
>fix the bug, we turn it into a pointer that is only set for initialized
>framebuffers. The fbdev's clean-up code skips uninitialized framebuffers.
>
>The memory for struct drm_framebuffer is allocated dynamically. This requires
>additional error handling within cirrusfb_create. The framebuffer clean-up is
>now performed by drm_framebuffer_put, which also frees the data strcuture's
>memory.
>
>Link: https://bugzilla.suse.com/show_bug.cgi?id=1101822
>Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>---
> drivers/gpu/drm/cirrus/cirrus_drv.h   |    2 -
> drivers/gpu/drm/cirrus/cirrus_fbdev.c |   49 ++++++++++++++++++++--------------
> drivers/gpu/drm/cirrus/cirrus_mode.c  |    2 -
> 3 files changed, 32 insertions(+), 21 deletions(-)
>
>--- a/drivers/gpu/drm/cirrus/cirrus_drv.h
>+++ b/drivers/gpu/drm/cirrus/cirrus_drv.h
>@@ -152,7 +152,7 @@ struct cirrus_device {
> 
> struct cirrus_fbdev {
> 	struct drm_fb_helper helper;
>-	struct cirrus_framebuffer gfb;
>+	struct cirrus_framebuffer *gfb;
> 	struct list_head fbdev_list;
> 	void *sysram;
> 	int size;
>--- a/drivers/gpu/drm/cirrus/cirrus_fbdev.c
>+++ b/drivers/gpu/drm/cirrus/cirrus_fbdev.c
>@@ -24,14 +24,14 @@ static void cirrus_dirty_update(struct c
> 	struct drm_gem_object *obj;
> 	struct cirrus_bo *bo;
> 	int src_offset, dst_offset;
>-	int bpp = (afbdev->gfb.base.bits_per_pixel + 7)/8;
>+	int bpp = (afbdev->gfb->base.bits_per_pixel + 7)/8;
> 	int ret = -EBUSY;
> 	bool unmap = false;
> 	bool store_for_later = false;
> 	int x2, y2;
> 	unsigned long flags;
> 
>-	obj = afbdev->gfb.obj;
>+	obj = afbdev->gfb->obj;
> 	bo = gem_to_cirrus_bo(obj);
> 
> 	/*
>@@ -84,7 +84,7 @@ static void cirrus_dirty_update(struct c
> 	}
> 	for (i = y; i < y + height; i++) {
> 		/* assume equal stride for now */
>-		src_offset = dst_offset = i * afbdev->gfb.base.pitches[0] + (x * bpp);
>+		src_offset = dst_offset = i * afbdev->gfb->base.pitches[0] + (x * bpp);
> 		memcpy_toio(bo->kmap.virtual + src_offset, afbdev->sysram + src_offset, width * bpp);
> 
> 	}
>@@ -167,7 +167,7 @@ static int cirrusfb_create(struct drm_fb
> 		container_of(helper, struct cirrus_fbdev, helper);
> 	struct cirrus_device *cdev = gfbdev->helper.dev->dev_private;
> 	struct fb_info *info;
>-	struct drm_framebuffer *fb;
>+	struct cirrus_framebuffer *fb;
> 	struct drm_mode_fb_cmd2 mode_cmd;
> 	void *sysram;
> 	struct drm_gem_object *gobj = NULL;
>@@ -194,33 +194,36 @@ static int cirrusfb_create(struct drm_fb
> 		return -ENOMEM;
> 
> 	info = drm_fb_helper_alloc_fbi(helper);
>-	if (IS_ERR(info))
>-		return PTR_ERR(info);
>+	if (IS_ERR(info)) {
>+		ret = PTR_ERR(info);
>+		goto err_vfree;
>+	}
> 
> 	info->par = gfbdev;
> 
>-	ret = cirrus_framebuffer_init(cdev->dev, &gfbdev->gfb, &mode_cmd, gobj);
>+	fb = kzalloc(sizeof(*fb), GFP_KERNEL);
>+	if (!fb) {
>+		ret = -ENOMEM;
>+		goto err_drm_gem_object_put_unlocked;
>+	}
>+
>+	ret = cirrus_framebuffer_init(cdev->dev, fb, &mode_cmd, gobj);
> 	if (ret)
>-		return ret;
>+		goto err_kfree;
> 
> 	gfbdev->sysram = sysram;
> 	gfbdev->size = size;
>-
>-	fb = &gfbdev->gfb.base;
>-	if (!fb) {
>-		DRM_INFO("fb is NULL\n");
>-		return -EINVAL;
>-	}
>+	gfbdev->gfb = fb;
> 
> 	/* setup helper */
>-	gfbdev->helper.fb = fb;
>+	gfbdev->helper.fb = &fb->base;
> 
> 	strcpy(info->fix.id, "cirrusdrmfb");
> 
> 	info->flags = FBINFO_DEFAULT;
> 	info->fbops = &cirrusfb_ops;
> 
>-	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->depth);
>+	drm_fb_helper_fill_fix(info, fb->base.pitches[0], fb->base.depth);
> 	drm_fb_helper_fill_var(info, &gfbdev->helper, sizes->fb_width,
> 			       sizes->fb_height);
> 
>@@ -240,16 +243,24 @@ static int cirrusfb_create(struct drm_fb
> 	DRM_INFO("fb mappable at 0x%lX\n", info->fix.smem_start);
> 	DRM_INFO("vram aper at 0x%lX\n", (unsigned long)info->fix.smem_start);
> 	DRM_INFO("size %lu\n", (unsigned long)info->fix.smem_len);
>-	DRM_INFO("fb depth is %d\n", fb->depth);
>-	DRM_INFO("   pitch is %d\n", fb->pitches[0]);
>+	DRM_INFO("fb depth is %d\n", fb->base.depth);
>+	DRM_INFO("   pitch is %d\n", fb->base.pitches[0]);
> 
> 	return 0;
>+
>+err_kfree:
>+	kfree(fb);
>+err_drm_gem_object_put_unlocked:
>+	drm_gem_object_unreference_unlocked(gobj);
>+err_vfree:
>+	vfree(sysram);
>+	return ret;
> }
> 
> static int cirrus_fbdev_destroy(struct drm_device *dev,
> 				struct cirrus_fbdev *gfbdev)
> {
>-	struct cirrus_framebuffer *gfb = &gfbdev->gfb;
>+	struct cirrus_framebuffer *gfb = gfbdev->gfb;
> 
> 	drm_fb_helper_unregister_fbi(&gfbdev->helper);
> 	drm_fb_helper_release_fbi(&gfbdev->helper);
>--- a/drivers/gpu/drm/cirrus/cirrus_mode.c
>+++ b/drivers/gpu/drm/cirrus/cirrus_mode.c
>@@ -164,7 +164,7 @@ static int cirrus_crtc_do_set_base(struc
> 		return ret;
> 	}
> 
>-	if (&cdev->mode_info.gfbdev->gfb == cirrus_fb) {
>+	if (cdev->mode_info.gfbdev->gfb == cirrus_fb) {
> 		/* if pushing console in kmap it */
> 		ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
> 		if (ret)

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Attachments on bug 1101822: 779781 | 779783 | 779797