Delete the lines after the last instance of the keyword

I have my input sometyhing like this

aaa
bbbbbb cccccc
ddddd eeeee
1234 ravi kumar
aaaaaa vvvvvvv
5678 ravi kumar
rrrrrrr mmmmmmm

I want the output as follows.

aaa
bbbbbb cccccc
ddddd eeeee
1234 ravi kumar
aaaaaa vvvvvvv
5678 ravi kumar

Please help.

i am using the below command for deleting the rows before the first occurrence of the key word

sed -n '/ravi/,/*/p' test.log

can some one please edit this command for the above mentioned usage?

 sed '/ravi/q' test.log

The command deletes all the lines after the first occurence of the keyword.. I need to delete the lines after the last occurrence of the keyword. Please help