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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-07-09 23:44:27 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-07-22 16:25:45 +0200 |
| commit | 169faecadd2444fc295c724c0a2f622b99e6bf19 (patch) | |
| tree | 16861beb9f0acb861ac7e1d571df9ddb098abff3 /drivers/gpu/drm/drm_fb_helper.c | |
| parent | 8c4ccc4ab6f64e859d4ff8d7c02c2ed2e956e07f (diff) | |
| download | linux-169faecadd2444fc295c724c0a2f622b99e6bf19.tar.gz linux-169faecadd2444fc295c724c0a2f622b99e6bf19.tar.bz2 linux-169faecadd2444fc295c724c0a2f622b99e6bf19.zip | |
drm/fbdev-helper: Grab mode_config.mutex in drm_fb_helper_single_add_all_connectors
This is now truly only duct-tape to keep locking checks happy since
calling this function when hpd or polling are already enabled is a
bug. The fbdev helper can't cope with hotplug changes yet at this
point, only after that.
Otoh a bit more robustness in this function can't hurt, and with this
fbdev can actually cope with hotplug changes. And it's also more
consistent with the connector hotadd/remove dp mst needs to do.
Therefore document this as new official behavior.
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 3630d92c9738..329d08167b77 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -89,8 +89,9 @@ static LIST_HEAD(kernel_fb_helper_list); * connectors to the fbdev, e.g. if some are reserved for special purposes or * not adequate to be used for the fbcon. * - * Since this is part of the initial setup before the fbdev is published, no - * locking is required. + * This function is protected against concurrent connector hotadds/removals + * using drm_fb_helper_add_one_connector() and + * drm_fb_helper_remove_one_connector(). */ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) { @@ -98,6 +99,7 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) struct drm_connector *connector; int i; + mutex_lock(&dev->mode_config.mutex); drm_for_each_connector(connector, dev) { struct drm_fb_helper_connector *fb_helper_connector; @@ -108,6 +110,7 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) fb_helper_connector->connector = connector; fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector; } + mutex_unlock(&dev->mode_config.mutex); return 0; fail: for (i = 0; i < fb_helper->connector_count; i++) { @@ -115,6 +118,8 @@ fail: fb_helper->connector_info[i] = NULL; } fb_helper->connector_count = 0; + mutex_unlock(&dev->mode_config.mutex); + return -ENOMEM; } EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors); |