bisecting fixing commit since 2762b48e9611529239da2e68cba908dbbec9805f
building syzkaller on 63631df1539816bc62c7be40779c5f3e23b23b2f
testing commit 2762b48e9611529239da2e68cba908dbbec9805f with gcc (GCC) 8.4.1 20210217
kernel signature: 79709c7669f0cc8034095b33f92a3f4303cb95aaa292e242fcd5f754731a2f39
run #0: crashed: INFO: task hung in grab_super
run #1: crashed: INFO: task hung in grab_super
run #2: crashed: INFO: task hung in grab_super
run #3: crashed: INFO: task hung in grab_super
run #4: crashed: INFO: task hung in grab_super
run #5: crashed: INFO: task hung in grab_super
run #6: crashed: INFO: task hung in grab_super
run #7: crashed: INFO: task hung in grab_super
run #8: crashed: INFO: task hung in grab_super
run #9: crashed: INFO: task hung in grab_super
run #10: crashed: INFO: task hung in grab_super
run #11: crashed: INFO: task hung in grab_super
run #12: crashed: INFO: task hung in grab_super
run #13: crashed: no output from test machine
run #14: crashed: no output from test machine
run #15: crashed: no output from test machine
run #16: crashed: no output from test machine
run #17: crashed: no output from test machine
run #18: crashed: no output from test machine
run #19: crashed: no output from test machine
testing current HEAD 670d6552eda8ff0c5f396d3d6f0174237917c66c
testing commit 670d6552eda8ff0c5f396d3d6f0174237917c66c with gcc (GCC) 8.4.1 20210217
kernel signature: e44b4ea038800394b01c88fdefc4171c9705e88a93ad7cc6220807025d187354
run #0: crashed: INFO: task hung in grab_super
run #1: crashed: INFO: task hung in grab_super
run #2: crashed: INFO: task hung in grab_super
run #3: crashed: INFO: task hung in grab_super
run #4: crashed: INFO: task hung in grab_super
run #5: crashed: INFO: task hung in grab_super
run #6: crashed: no output from test machine
run #7: crashed: no output from test machine
run #8: crashed: no output from test machine
run #9: crashed: no output from test machine
revisions tested: 2, total time: 30m59.86212626s (build: 14m27.177422955s, test: 16m10.866315156s)
the crash still happens on HEAD
commit msg: Linux 4.14.227
crash: no output from test machine