From ae1287865f5361fa138d4d3b1b6277908b54eac9 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Thu, 24 Jan 2013 16:12:41 +1000 Subject: fbcon: don't lose the console font across generic->chip driver switch If grub2 loads efifb/vesafb, then when systemd starts it can set the console font on that framebuffer device, however when we then load the native KMS driver, the first thing it does is tear down the generic framebuffer driver. The thing is the generic code is doing the right thing, it frees the font because otherwise it would leak memory. However we can assume that if you are removing the generic firmware driver (vesa/efi/offb), that a new driver *should* be loading soon after, so we effectively leak the font. However the old code left a dangling pointer in vc->vc_font.data and we can now reuse that dangling pointer to load the font into the new driver, now that we aren't freeing it. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=892340 Cc: Kay Sievers Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie --- drivers/video/console/fbcon.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'drivers/video/console/fbcon.c') diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index fdefa8fd72c4..f8dbe76a1b6f 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -990,7 +990,7 @@ static const char *fbcon_startup(void) } /* Setup default font */ - if (!p->fontdata) { + if (!p->fontdata && !vc->vc_font.data) { if (!fontname[0] || !(font = find_font(fontname))) font = get_default_font(info->var.xres, info->var.yres, @@ -1000,6 +1000,8 @@ static const char *fbcon_startup(void) vc->vc_font.height = font->height; vc->vc_font.data = (void *)(p->fontdata = font->data); vc->vc_font.charcount = 256; /* FIXME Need to support more fonts */ + } else { + p->fontdata = vc->vc_font.data; } cols = FBCON_SWAP(ops->rotate, info->var.xres, info->var.yres); @@ -1159,9 +1161,9 @@ static void fbcon_init(struct vc_data *vc, int init) ops->p = &fb_display[fg_console]; } -static void fbcon_free_font(struct display *p) +static void fbcon_free_font(struct display *p, bool freefont) { - if (p->userfont && p->fontdata && (--REFCOUNT(p->fontdata) == 0)) + if (freefont && p->userfont && p->fontdata && (--REFCOUNT(p->fontdata) == 0)) kfree(p->fontdata - FONT_EXTRA_WORDS * sizeof(int)); p->fontdata = NULL; p->userfont = 0; @@ -1173,8 +1175,8 @@ static void fbcon_deinit(struct vc_data *vc) struct fb_info *info; struct fbcon_ops *ops; int idx; + bool free_font = true; - fbcon_free_font(p); idx = con2fb_map[vc->vc_num]; if (idx == -1) @@ -1185,6 +1187,8 @@ static void fbcon_deinit(struct vc_data *vc) if (!info) goto finished; + if (info->flags & FBINFO_MISC_FIRMWARE) + free_font = false; ops = info->fbcon_par; if (!ops) @@ -1196,6 +1200,8 @@ static void fbcon_deinit(struct vc_data *vc) ops->flags &= ~FBCON_FLAGS_INIT; finished: + fbcon_free_font(p, free_font); + if (!con_is_bound(&fb_con)) fbcon_exit(); -- cgit v1.2.3 From 50e244cc793d511b86adea24972f3a7264cae114 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 25 Jan 2013 10:28:15 +1000 Subject: fb: rework locking to fix lock ordering on takeover Adjust the console layer to allow a take over call where the caller already holds the locks. Make the fb layer lock in order. This is partly a band aid, the fb layer is terminally confused about the locking rules it uses for its notifiers it seems. [akpm@linux-foundation.org: remove stray non-ascii char, tidy comment] [akpm@linux-foundation.org: export do_take_over_console()] [airlied: cleanup another non-ascii char] Signed-off-by: Alan Cox Cc: Florian Tobias Schandinat Cc: Stephen Rothwell Cc: Jiri Kosina Cc: stable Tested-by: Sedat Dilek Reviewed-by: Daniel Vetter Signed-off-by: Andrew Morton Signed-off-by: Dave Airlie --- drivers/video/console/fbcon.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) (limited to 'drivers/video/console/fbcon.c') diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index fdefa8fd72c4..4bd7820cf4d0 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -529,6 +529,33 @@ static int search_for_mapped_con(void) return retval; } +static int do_fbcon_takeover(int show_logo) +{ + int err, i; + + if (!num_registered_fb) + return -ENODEV; + + if (!show_logo) + logo_shown = FBCON_LOGO_DONTSHOW; + + for (i = first_fb_vc; i <= last_fb_vc; i++) + con2fb_map[i] = info_idx; + + err = do_take_over_console(&fb_con, first_fb_vc, last_fb_vc, + fbcon_is_default); + + if (err) { + for (i = first_fb_vc; i <= last_fb_vc; i++) + con2fb_map[i] = -1; + info_idx = -1; + } else { + fbcon_has_console_bind = 1; + } + + return err; +} + static int fbcon_takeover(int show_logo) { int err, i; @@ -3115,7 +3142,7 @@ static int fbcon_fb_registered(struct fb_info *info) } if (info_idx != -1) - ret = fbcon_takeover(1); + ret = do_fbcon_takeover(1); } else { for (i = first_fb_vc; i <= last_fb_vc; i++) { if (con2fb_map_boot[i] == idx) -- cgit v1.2.3 From e93a9a868792ad71cdd09d75e5a02d8067473c4e Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 25 Jan 2013 10:28:18 +1000 Subject: fb: Yet another band-aid for fixing lockdep mess I've still got lockdep warnings even after Alan's patch, and it seems that yet more band aids are required to paper over similar paths for unbind_con_driver() and unregister_con_driver(). After this hack, lockdep warnings are finally gone. Signed-off-by: Takashi Iwai Cc: Alan Cox Cc: Florian Tobias Schandinat Cc: Jiri Kosina Cc: stable Tested-by: Sedat Dilek Signed-off-by: Andrew Morton Signed-off-by: Dave Airlie --- drivers/video/console/fbcon.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/video/console/fbcon.c') diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index 4bd7820cf4d0..2aef9cac4d18 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -3004,7 +3004,7 @@ static int fbcon_unbind(void) { int ret; - ret = unbind_con_driver(&fb_con, first_fb_vc, last_fb_vc, + ret = do_unbind_con_driver(&fb_con, first_fb_vc, last_fb_vc, fbcon_is_default); if (!ret) @@ -3077,7 +3077,7 @@ static int fbcon_fb_unregistered(struct fb_info *info) primary_device = -1; if (!num_registered_fb) - unregister_con_driver(&fb_con); + do_unregister_con_driver(&fb_con); return 0; } -- cgit v1.2.3 From 054430e773c9a1e26f38e30156eff02dedfffc17 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Fri, 25 Jan 2013 11:38:56 +1000 Subject: 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: Maarten Lankhorst Tested-by: Lu Hua Signed-off-by: Dave Airlie --- drivers/video/console/fbcon.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/video/console/fbcon.c') diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index 2aef9cac4d18..2e2d959acae6 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); -- cgit v1.2.3