From f231976c2e8964ceaa9250e57d27c35ff03825c2 Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Fri, 2 Oct 2015 14:03:19 +1000 Subject: [PATCH] drm/nouveau/fbcon: take runpm reference when userspace has an open fd We need to do this in order to prevent accesses to the device while it's powered down. Userspace may have an mmap of the fb, and there's no good way (that I know of) to prevent it from touching the device otherwise. This fixes some nasty races between runpm and plymouth on some systems, which result in the GPU getting very upset and hanging the boot. Signed-off-by: Ben Skeggs Cc: stable@vger.kernel.org --- drivers/gpu/drm/nouveau/nouveau_fbcon.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c b/drivers/gpu/drm/nouveau/nouveau_fbcon.c index 2791701685dc..59f27e774acb 100644 --- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c +++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c @@ -178,8 +178,30 @@ nouveau_fbcon_sync(struct fb_info *info) return 0; } +static int +nouveau_fbcon_open(struct fb_info *info, int user) +{ + struct nouveau_fbdev *fbcon = info->par; + struct nouveau_drm *drm = nouveau_drm(fbcon->dev); + int ret = pm_runtime_get_sync(drm->dev->dev); + if (ret < 0 && ret != -EACCES) + return ret; + return 0; +} + +static int +nouveau_fbcon_release(struct fb_info *info, int user) +{ + struct nouveau_fbdev *fbcon = info->par; + struct nouveau_drm *drm = nouveau_drm(fbcon->dev); + pm_runtime_put(drm->dev->dev); + return 0; +} + static struct fb_ops nouveau_fbcon_ops = { .owner = THIS_MODULE, + .fb_open = nouveau_fbcon_open, + .fb_release = nouveau_fbcon_release, .fb_check_var = drm_fb_helper_check_var, .fb_set_par = drm_fb_helper_set_par, .fb_fillrect = nouveau_fbcon_fillrect, @@ -195,6 +217,8 @@ static struct fb_ops nouveau_fbcon_ops = { static struct fb_ops nouveau_fbcon_sw_ops = { .owner = THIS_MODULE, + .fb_open = nouveau_fbcon_open, + .fb_release = nouveau_fbcon_release, .fb_check_var = drm_fb_helper_check_var, .fb_set_par = drm_fb_helper_set_par, .fb_fillrect = drm_fb_helper_cfb_fillrect, -- 2.20.1