Take the appropriate action and verify that the warning light turns off.

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Manual Transaxle Shift Pattern
The shift pattern of the transaxle is conventional, as shown.
Depress the clutch pedal all the way down while shifting; then release it slowly.
Your vehicle is equipped with a device to prevent shifting to R (reverse) by mistake. Push the shift lever downward and shift to R.
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Mazda 6 Owners Manual: Dynamic Stability Control (DSC)
The Dynamic Stability Control (DSC) automatically controls braking and engine
torque in conjunction with systems such as ABS and TCS to help control side slip
when driving on slippery surfaces, or during sudden or evasive maneuvering, enhancing
vehicle safety.
Refer to ABS and TCS.
DSC opera ...