Messages in this thread | | | Date | Sat, 13 Nov 2021 08:31:15 +0100 | From | Peter Zijlstra <> | Subject | Re: vmlinux.o: warning: objtool: kvm_spurious_fault()+0x22: call to ftrace_likely_update() leaves .noinstr.text section |
| |
On Sat, Nov 13, 2021 at 10:48:52AM +0800, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > head: 66f4beaa6c1d28161f534471484b2daa2de1dce0 > commit: 63b3f96e1a989846a5a521d4fbef4bc86406929d kvm: Select SCHED_INFO instead of TASK_DELAY_ACCT > date: 6 months ago > config: x86_64-buildonly-randconfig-r002-20211009 (attached as .config) > compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 > reproduce (this is a W=1 build): > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=63b3f96e1a989846a5a521d4fbef4bc86406929d > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > git fetch --no-tags linus master > git checkout 63b3f96e1a989846a5a521d4fbef4bc86406929d > # save the attached .config to linux build tree > mkdir build_dir > make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <lkp@intel.com> > > All warnings (new ones prefixed by >>): > > >> vmlinux.o: warning: objtool: kvm_spurious_fault()+0x22: call to ftrace_likely_update() leaves .noinstr.text section > >> vmlinux.o: warning: objtool: vmx_update_host_rsp()+0x34: call to ftrace_likely_update() leaves .noinstr.text section
Yeah, that's CONFIG_TRACE_BRANCH_PROFILING and it is broken. It will eventually explode once we push the PTI CR3 switcheroo into C due to trying to access kernel data before kernel address space is mapped.
| |