Re: [PATCH -tip 0/2] x86: Prohibit kprobes on XEN_EMULATE_PREFIX

[Peter Zijlstra]

On Wed, Sep 04, 2019 at 08:45:47PM +0900, Masami Hiramatsu wrote:
> Hi,
> 
> These patches allow x86 instruction decoder to decode
> xen-cpuid which has XEN_EMULATE_PREFIX, and prohibit
> kprobes to probe on it.
> 
> Josh reported that the objtool can not decode such special
> prefixed instructions, and I found that we also have to
> prohibit kprobes to probe on such instruction.
> 
> This series can be applied on -tip master branch which
> has merged Josh's objtool/perf sharing common x86 insn
> decoder series.
> 
> 
> Thank you,
> 
> ---
> 
> Masami Hiramatsu (2):
>       x86: xen: insn: Decode XEN_EMULATE_PREFIX correctly
>       x86: kprobes: Prohibit probing on instruction which has Xen prefix
> 
> 
>  arch/x86/include/asm/insn.h             |    2 +
>  arch/x86/include/asm/xen/interface.h    |    7 ++++-
>  arch/x86/include/asm/xen/prefix.h       |   10 +++++++
>  arch/x86/kernel/kprobes/core.c          |    4 +++
>  arch/x86/lib/insn.c                     |   43 +++++++++++++++++++++++++++++++
>  tools/arch/x86/include/asm/insn.h       |    2 +
>  tools/arch/x86/include/asm/xen/prefix.h |   10 +++++++
>  tools/arch/x86/lib/insn.c               |   43 +++++++++++++++++++++++++++++++
>  tools/objtool/sync-check.sh             |    3 +-
>  9 files changed, 121 insertions(+), 3 deletions(-)
>  create mode 100644 arch/x86/include/asm/xen/prefix.h
>  create mode 100644 tools/arch/x86/include/asm/xen/prefix.h

Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>