Hi Chen,

Thanks for pitching in and providing your inputs :-)

On 01/07/22 07:43, Chen Zhongjin wrote:

Hi everyone,

Hope I'm not too late for this discussion.

I'm not familiar with ppc so it spent me some time to reproduce this. 
But at last I didn't make it.

What I did:

1 checkout to tip/objtool/core

2 apply this patch

3 recover the unreachable() after WARN_ENTRY(..

4 compile on defconfig/allyesconfig

If anyone can point out which file will generate this problem it will 
be perfect.

To reproduce this problem, you may want to apply this patch series on 
top of objtool/core branch of the tip tree, and compile on 
ppc64le_defconfig.

There are a couple of C files that are generating these warnings. One 
such file is: arch/powerpc/kvm/../../../virt/kvm/kvm_main.o which gives
*arch/powerpc/kvm/../../../virt/kvm/kvm_main.o: warning: objtool: 
kvm_mmu_notifier_release+0x6c: unannotated intra-function call* warning.

With unreachable() in __WARN_FLAGS(), we get unannotated intra-function 
call warnings, but without unreachable() like in patch 11/12 or with 
just the builtin variant of unreachable (__builtin_unreachable()) 
instead of unreachable(), we do not get those warnings.


- Sathvika