Commit 054430e7 authored by Dave Airlie's avatar Dave Airlie Committed by Dave Airlie
Browse files

fbcon: fix locking harder 



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: default avatarMaarten Lankhorst <maarten.lankhorst@canonical.com>
Tested-by: default avatarLu Hua <huax.lu@intel.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent e93a9a86

drivers/gpu/vga/vga_switcheroo.c

+3 −0
Original line number Diff line number Diff line
@@ -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 vga_switcheroo_client *new_client) 


	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);

drivers/video/console/fbcon.c

+8 −3
Original line number Diff line number Diff line
@@ -842,6 +842,8 @@ static void con2fb_init_display(struct vc_data *vc, struct fb_info *info, 
 *

 *	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 newidx, int user) 


	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 newidx, int user) 


	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 newidx, int user) 
	if (!search_fb_in_map(info_idx))

		info_idx = newidx;



	console_unlock();

 	return err;

}
@@ -3019,6 +3019,7 @@ 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;
@@ -3045,6 +3046,7 @@ 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;
@@ -3082,6 +3084,7 @@ static int fbcon_fb_unregistered(struct fb_info *info) 
	return 0;

}



/* called with console_lock held */

static void fbcon_remap_all(int idx)

{

	int i;
@@ -3126,6 +3129,7 @@ static inline void fbcon_select_primary(struct fb_info *info) 
}

#endif /* CONFIG_FRAMEBUFFER_DETECT_PRIMARY */



/* called with console_lock held */

static int fbcon_fb_registered(struct fb_info *info)

{

	int ret = 0, i, idx;
@@ -3278,6 +3282,7 @@ static int fbcon_event_notify(struct notifier_block *self, 
		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);

drivers/video/fbmem.c

+2 −0
Original line number Diff line number Diff line
@@ -1177,8 +1177,10 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, 
		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:

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