On Thu, Mar 07, 2019 at 12:45:26PM +0100, Peter Zijlstra wrote: > For when you want to know the path that reached your fail state. > > $ ./objtool check --no-fp --backtrace arch/x86/lib/usercopy_64.o > arch/x86/lib/usercopy_64.o: warning: objtool: .altinstr_replacement+0x3: > UACCESS disable without MEMOPs: __clear_user() > arch/x86/lib/usercopy_64.o: warning: objtool: __clear_user()+0x3a: (alt) > arch/x86/lib/usercopy_64.o: warning: objtool: __clear_user()+0x2e: (branch) > arch/x86/lib/usercopy_64.o: warning: objtool: __clear_user()+0x18: (branch) > arch/x86/lib/usercopy_64.o: warning: objtool: > .altinstr_replacement+0xffffffffffffffff: (branch) > arch/x86/lib/usercopy_64.o: warning: objtool: __clear_user()+0x5: (alt) > arch/x86/lib/usercopy_64.o: warning: objtool: __clear_user()+0x0: <=== > (func)
We should have done this a long time ago. Thank you for this! -- Josh
