[PATCH] fbcon: fix locking harder
From: Dave Airlie <airlied@gmail.com>
Date: 2013-01-25 01:44:00
Also in:
lkml
Subsystem:
console subsystem, drm drivers, drm drivers and misc gpu patches, framebuffer layer, the rest, vga_switcheroo · Maintainers:
Greg Kroah-Hartman, David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Helge Deller, Linus Torvalds
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. Signed-off-by: Dave Airlie <airlied@redhat.com> --- 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(-)
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index fa60add..cf787e1 100644
--- 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 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);
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 2aef9ca..2e2d959 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c@@ -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);
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index 070b9a1..dc61c12 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c@@ -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:
--
1.8.1