This extracts all the error from output of checkpatch.pl

error_append

#!/bin/bash

git log v5.7..v5.8 --format=format:"%H" --no-merges &> ./hashes.txt

input="./hashes.txt"
while IFS= read -r line
do
  err=$(./scripts/checkpatch.pl --git "$line" --mailback --terse --show-types)
  type=$(echo $err| cut -d':' -f 3,4)
  echo "$type" >> errors.txt 
done < "$input"

rm ./hashes.txt
#This is for most frequent error
cat errors.txt | sort | uniq -c | sort -n | tail -n1
#To list all the occuring errors
cat errors.txt | sort | uniq -c | sort

rm ./errors.txt