next-20190125 - objtool complains about dumpstack

[valdis . kletnieks]

Seen in a build:

  CC      arch/x86/kernel/dumpstack.o
arch/x86/kernel/dumpstack.o: warning: objtool: oops_begin()+0x9: undefined stack state
arch/x86/kernel/dumpstack.o: warning: objtool: oops_begin()+0x0: stack state mismatch: cfa1=6+16 cfa2=7+8

Probably a gcc9 code generation that objtool doesn't know about?