Kill Bill" star Michael Madsen was arrested in L.A. today on suspicion of felony child endangerment ... TMZ has learned. Law enforcement tells us ... Madsen was arrested in Malibu at 3:55 PM PST ... and he was taken to a nearby Sheriff's Dept. We're told police responded to a call about a family dispute at Madsen's Malibu home. According to law enforcement -- Madsen had gotten into a physical fight with his juvenile son -- and when cops arrived, they observed several signs of injury on his son. We're told Madsen also appeared to be under the influence of alcohol at the time of his arrest. We're told his son did not require medical attention. We're told Madsen was booked on a charge of child endangerment with cruelty to a child -- a felony. He is currently being held on $100,000 bail. Do you think he tried to cut his kid's ear off?