6.6-stable review patch. If anyone has any objections, please let me know.
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From: Wentong Wu wentong.wu@intel.com
commit c6be6471004e0e4d10d0514146d8c41550823d63 upstream.
There're possibilities that privacy status change notification happens in the middle of the ongoing mei command which already takes the command lock, but v4l2_ctrl_s_ctrl() would also need the same lock prior to this patch, so this may results in circular locking problem. This patch adds one dedicated lock for v4l2 control handler to avoid described issue.
Fixes: 29006e196a56 ("media: pci: intel: ivsc: Add CSI submodule") Cc: stable@vger.kernel.org # for 6.6 and later Reported-by: Hao Yao hao.yao@intel.com Signed-off-by: Wentong Wu wentong.wu@intel.com Tested-by: Jason Chen jason.z.chen@intel.com Signed-off-by: Sakari Ailus sakari.ailus@linux.intel.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/pci/intel/ivsc/mei_csi.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/drivers/media/pci/intel/ivsc/mei_csi.c +++ b/drivers/media/pci/intel/ivsc/mei_csi.c @@ -124,6 +124,8 @@ struct mei_csi { struct v4l2_ctrl_handler ctrl_handler; struct v4l2_ctrl *freq_ctrl; struct v4l2_ctrl *privacy_ctrl; + /* lock for v4l2 controls */ + struct mutex ctrl_lock; unsigned int remote_pad; /* start streaming or not */ int streaming; @@ -609,11 +611,13 @@ static int mei_csi_init_controls(struct u32 max; int ret;
+ mutex_init(&csi->ctrl_lock); + ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 2); if (ret) return ret;
- csi->ctrl_handler.lock = &csi->lock; + csi->ctrl_handler.lock = &csi->ctrl_lock;
max = ARRAY_SIZE(link_freq_menu_items) - 1; csi->freq_ctrl = v4l2_ctrl_new_int_menu(&csi->ctrl_handler, @@ -772,6 +776,7 @@ err_entity:
err_ctrl_handler: v4l2_ctrl_handler_free(&csi->ctrl_handler); + mutex_destroy(&csi->ctrl_lock); v4l2_async_nf_unregister(&csi->notifier); v4l2_async_nf_cleanup(&csi->notifier);
@@ -791,6 +796,7 @@ static void mei_csi_remove(struct mei_cl v4l2_async_nf_unregister(&csi->notifier); v4l2_async_nf_cleanup(&csi->notifier); v4l2_ctrl_handler_free(&csi->ctrl_handler); + mutex_destroy(&csi->ctrl_lock); v4l2_async_unregister_subdev(&csi->subdev); v4l2_subdev_cleanup(&csi->subdev); media_entity_cleanup(&csi->subdev.entity);