This is a note to let you know that I've just added the patch titled fbcon: fix locking harder to the 3.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fbcon-fix-locking-harder.patch and it can be found in the queue-3.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 054430e773c9a1e26f38e30156eff02dedfffc17 Mon Sep 17 00:00:00 2001 From: Dave Airlie <airlied@xxxxxxxxx> Date: Fri, 25 Jan 2013 11:38:56 +1000 Subject: fbcon: fix locking harder From: Dave Airlie <airlied@xxxxxxxxx> commit 054430e773c9a1e26f38e30156eff02dedfffc17 upstream. Okay so Alan's patch handled the case where there was no registered fbcon, however the other path entered in set_con2fb_map pit. In there we called fbcon_takeover, but we also took the console lock in a couple of places. So push the console lock out to the callers of set_con2fb_map, this means fbmem and switcheroo needed to take the lock around the fb notifier entry points that lead to this. This should fix the efifb regression seen by Maarten. Tested-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx> Tested-by: Lu Hua <huax.lu@xxxxxxxxx> Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/vga/vga_switcheroo.c | 3 +++ drivers/video/console/fbcon.c | 11 ++++++++--- drivers/video/fbmem.c | 2 ++ 3 files changed, 13 insertions(+), 3 deletions(-) --- a/drivers/gpu/vga/vga_switcheroo.c +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -25,6 +25,7 @@ #include <linux/fb.h> #include <linux/pci.h> +#include <linux/console.h> #include <linux/vga_switcheroo.h> #include <linux/vgaarb.h> @@ -337,8 +338,10 @@ static int vga_switchto_stage2(struct vg if (new_client->fb_info) { struct fb_event event; + console_lock(); event.info = new_client->fb_info; fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event); + console_unlock(); } ret = vgasr_priv.handler->switchto(new_client->id); --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -842,6 +842,8 @@ static void con2fb_init_display(struct v * * Maps a virtual console @unit to a frame buffer device * @newidx. + * + * This should be called with the console lock held. */ static int set_con2fb_map(int unit, int newidx, int user) { @@ -859,7 +861,7 @@ static int set_con2fb_map(int unit, int if (!search_for_mapped_con() || !con_is_bound(&fb_con)) { info_idx = newidx; - return fbcon_takeover(0); + return do_fbcon_takeover(0); } if (oldidx != -1) @@ -867,7 +869,6 @@ static int set_con2fb_map(int unit, int found = search_fb_in_map(newidx); - console_lock(); con2fb_map[unit] = newidx; if (!err && !found) err = con2fb_acquire_newinfo(vc, info, unit, oldidx); @@ -894,7 +895,6 @@ static int set_con2fb_map(int unit, int if (!search_fb_in_map(info_idx)) info_idx = newidx; - console_unlock(); return err; } @@ -3025,6 +3025,7 @@ static inline int fbcon_unbind(void) } #endif /* CONFIG_VT_HW_CONSOLE_BINDING */ +/* called with console_lock held */ static int fbcon_fb_unbind(int idx) { int i, new_idx = -1, ret = 0; @@ -3051,6 +3052,7 @@ static int fbcon_fb_unbind(int idx) return ret; } +/* called with console_lock held */ static int fbcon_fb_unregistered(struct fb_info *info) { int i, idx; @@ -3088,6 +3090,7 @@ static int fbcon_fb_unregistered(struct return 0; } +/* called with console_lock held */ static void fbcon_remap_all(int idx) { int i; @@ -3132,6 +3135,7 @@ static inline void fbcon_select_primary( } #endif /* CONFIG_FRAMEBUFFER_DETECT_PRIMARY */ +/* called with console_lock held */ static int fbcon_fb_registered(struct fb_info *info) { int ret = 0, i, idx; @@ -3284,6 +3288,7 @@ static int fbcon_event_notify(struct not ret = fbcon_fb_unregistered(info); break; case FB_EVENT_SET_CONSOLE_MAP: + /* called with console lock held */ con2fb = event->data; ret = set_con2fb_map(con2fb->console - 1, con2fb->framebuffer, 1); --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1177,8 +1177,10 @@ static long do_fb_ioctl(struct fb_info * event.data = &con2fb; if (!lock_fb_info(info)) return -ENODEV; + console_lock(); event.info = info; ret = fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP, &event); + console_unlock(); unlock_fb_info(info); break; case FBIOBLANK: Patches currently in stable-queue which might be from airlied@xxxxxxxxx are queue-3.8/drm-use-c8-instead-of-rgb332-when-determining-the-format-from-depth-bpp.patch queue-3.8/drm-fill-depth-bits_per_pixel-for-c8-format.patch queue-3.8/fbcon-fix-locking-harder.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html