Re: [linus:master] BUILD REGRESSION a2e5790d841658485d642196dbb0927303d6c22f

[Linus Torvalds]

Adding more people for this funky warning from the kbuild robot.

Something is confused. UD0 is 0f ff, the bytes after that shouldn't
matter. But I guess they can be interpreted as modrm bytes, and
somebody started doing that.

That said, intel only _documents_ UD2 (0f 0b).

Maybe we should avoid using UD0/UD1 entirely.

              Linus

On Wed, Feb 7, 2018 at 3:44 AM, kbuild test robot
<fengguang.wu@xxxxxxxxx> wrote:
> tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git  master
> branch HEAD: a2e5790d841658485d642196dbb0927303d6c22f  Merge branch 'akpm' (patches from Andrew)
>
> Regressions in current branch:
>
> arch/x86/tools/insn_decoder_test: warning: ffffffff810010d7:    0f ff eb                ud0    %ebx,%ebp
> arch/x86/tools/insn_decoder_test: warning: ffffffff81001152:    0f ff bf 09 00 00 00    ud0    0x9(%rdi),%edi
> arch/x86/tools/insn_decoder_test: warning: ffffffff81001275:    0f ff eb                ud0    %ebx,%ebp
> arch/x86/tools/insn_decoder_test: warning: ffffffff810013fd:    0f ff bf 09 00 00 00    ud0    0x9(%rdi),%edi
> arch/x86/tools/insn_decoder_test: warning: ffffffff81001499:    0f ff bf 09 00 00 00    ud0    0x9(%rdi),%edi
> arch/x86/tools/insn_decoder_test: warning: ffffffff812296eb:    0f ff e8                ud0    %eax,%ebp