From: Chris Wilson chris@chris-wilson.co.uk

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 46eeb2c144956e88197439b5ee5cf221a91b0a81 upstream.

If we fail to remove a conflicting fb driver, we need to abort the loading of the second driver to avoid likely kernel panics.

Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Jean-Christophe Plagniol-Villard plagnioj@jcrosoft.com Cc: Tomi Valkeinen tomi.valkeinen@ti.com Cc: linux-fbdev@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Reviewed-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Dave Airlie airlied@redhat.com Signed-off-by: Jiri Slaby jslaby@suse.cz --- drivers/video/fbmem.c | 31 +++++++++++++++++++++---------- include/linux/fb.h | 4 ++-- 2 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index cde461932760..7309ac704e26 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1577,10 +1577,10 @@ static bool fb_do_apertures_overlap(struct apertures_struct *gena, static int do_unregister_framebuffer(struct fb_info *fb_info);

#define VGA_FB_PHYS 0xA0000 -static void do_remove_conflicting_framebuffers(struct apertures_struct *a, - const char *name, bool primary) +static int do_remove_conflicting_framebuffers(struct apertures_struct *a, + const char *name, bool primary) { - int i; + int i, ret;

/* check all firmware fbs and kick off if the base addr overlaps */ for (i = 0 ; i < FB_MAX; i++) { @@ -1599,22 +1599,29 @@ static void do_remove_conflicting_framebuffers(struct apertures_struct *a, printk(KERN_INFO "fb: conflicting fb hw usage " "%s vs %s - removing generic driver\n", name, registered_fb[i]->fix.id); - do_unregister_framebuffer(registered_fb[i]); + ret = do_unregister_framebuffer(registered_fb[i]); + if (ret) + return ret; } } + + return 0; }

static int do_register_framebuffer(struct fb_info *fb_info) { - int i; + int i, ret; struct fb_event event; struct fb_videomode mode;

if (fb_check_foreignness(fb_info)) return -ENOSYS;

- do_remove_conflicting_framebuffers(fb_info->apertures, fb_info->fix.id, - fb_is_primary_device(fb_info)); + ret = do_remove_conflicting_framebuffers(fb_info->apertures, + fb_info->fix.id, + fb_is_primary_device(fb_info)); + if (ret) + return ret;

if (num_registered_fb == FB_MAX) return -ENXIO; @@ -1739,12 +1746,16 @@ int unlink_framebuffer(struct fb_info *fb_info) } EXPORT_SYMBOL(unlink_framebuffer);

-void remove_conflicting_framebuffers(struct apertures_struct *a, - const char *name, bool primary) +int remove_conflicting_framebuffers(struct apertures_struct *a, + const char *name, bool primary) { + int ret; + mutex_lock(&registration_lock); - do_remove_conflicting_framebuffers(a, name, primary); + ret = do_remove_conflicting_framebuffers(a, name, primary); mutex_unlock(&registration_lock); + + return ret; } EXPORT_SYMBOL(remove_conflicting_framebuffers);

diff --git a/include/linux/fb.h b/include/linux/fb.h index ffac70aab3e9..8439a1600c1a 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -613,8 +613,8 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf, extern int register_framebuffer(struct fb_info *fb_info); extern int unregister_framebuffer(struct fb_info *fb_info); extern int unlink_framebuffer(struct fb_info *fb_info); -extern void remove_conflicting_framebuffers(struct apertures_struct *a, - const char *name, bool primary); +extern int remove_conflicting_framebuffers(struct apertures_struct *a, + const char *name, bool primary); extern int fb_prepare_logo(struct fb_info *fb_info, int rotate); extern int fb_show_logo(struct fb_info *fb_info, int rotate); extern char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size);