From patchwork Wed Apr 24 19:41:08 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brad Figg X-Patchwork-Id: 239311 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 1DC132C00FF for ; Thu, 25 Apr 2013 05:41:18 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UV5Z0-0003El-UE; Wed, 24 Apr 2013 19:41:10 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UV5Yz-0003Dx-MX for kernel-team@lists.ubuntu.com; Wed, 24 Apr 2013 19:41:09 +0000 Received: from static-50-53-107-235.bvtn.or.frontiernet.net ([50.53.107.235] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1UV5Yz-0001Oe-68 for kernel-team@lists.ubuntu.com; Wed, 24 Apr 2013 19:41:09 +0000 From: Brad Figg To: kernel-team@lists.ubuntu.com Subject: [QUANTAL] [PATCH 1/1] fbcon: fix locking harder Date: Wed, 24 Apr 2013 12:41:08 -0700 Message-Id: <1366832468-11502-2-git-send-email-brad.figg@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1366832468-11502-1-git-send-email-brad.figg@canonical.com> References: <1366832468-11502-1-git-send-email-brad.figg@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com From: Dave Airlie BugLink: http://bugs.launchpad.net/bugs/1169380 BugLink: http://bugs.launchpad.net/bugs/1168961 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 (backported from commit 054430e773c9a1e26f38e30156eff02dedfffc17 upstream) Just context changes Signed-off-by: Brad Figg --- 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 58434e8..37fe246 100644 --- a/drivers/gpu/vga/vga_switcheroo.c +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -26,6 +26,7 @@ #include #include +#include #include struct vga_switcheroo_client { @@ -256,8 +257,10 @@ 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 9b8bcab..7a36dff 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -843,6 +843,8 @@ 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) { @@ -860,7 +862,7 @@ 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) @@ -868,7 +870,6 @@ 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); @@ -895,7 +896,6 @@ 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; } @@ -3026,6 +3026,7 @@ 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; @@ -3052,6 +3053,7 @@ 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; @@ -3089,6 +3091,7 @@ 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; @@ -3133,6 +3136,7 @@ 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; @@ -3285,6 +3289,7 @@ 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 c133dde..babbb07 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1154,8 +1154,10 @@ 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: