From 5b215bcff50d549d73e43c09bcccf8eebcc95bac Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Tue, 5 Aug 2014 10:40:20 +1000 Subject: [PATCH] drm/i915: lock around link status and link training. We need to take the connection mutex around the link status check for non-MST case, but also around the MST link training on short HPDs. I suspect we actually should have a dpcd lock in the future as well, that just lock the local copies of dpcd and flags stored from that. Reviewed-by: Daniel Vetter Signed-off-by: Dave Airlie --- drivers/gpu/drm/i915/intel_dp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index ea6ff71b2910..eb52ecfe14cf 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3535,11 +3535,13 @@ go_again: void intel_dp_check_link_status(struct intel_dp *intel_dp) { + struct drm_device *dev = intel_dp_to_dev(intel_dp); struct intel_encoder *intel_encoder = &dp_to_dig_port(intel_dp)->base; u8 sink_irq_vector; u8 link_status[DP_LINK_STATUS_SIZE]; - /* FIXME: This access isn't protected by any locks. */ + WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex)); + if (!intel_encoder->connectors_active) return; @@ -4058,7 +4060,9 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) * we'll check the link status via the normal hot plug path later - * but for short hpds we should check it now */ + drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); intel_dp_check_link_status(intel_dp); + drm_modeset_unlock(&dev->mode_config.connection_mutex); } } return false; -- 2.20.1