git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From foo@baz Sun Jun 17 12:13:49 CEST 2018
   2 From: Ingo Molnar <mingo@kernel.org>
   3 Date: Mon, 14 May 2018 10:15:54 +0200
   4 Subject: objtool, kprobes/x86: Sync the latest <asm/insn.h> header with tools/objtool/arch/x86/include/asm/insn.h
   5
   6 From: Ingo Molnar <mingo@kernel.org>
   7
   8 [ Upstream commit 4fe875e4bd3cae85ae6f6eaf77f63fabe613b66e ]
   9
  10 The following commit:
  11
  12   ee6a7354a362: kprobes/x86: Prohibit probing on exception masking instructions
  13
  14 Modified <asm/insn.h>, adding the insn_masking_exception() function.
  15
  16 Sync the tooling version of the header to it, to fix this warning:
  17
  18   Warning: synced file at 'tools/objtool/arch/x86/include/asm/insn.h' differs from latest kernel version at 'arch/x86/include/asm/insn.h'
  19
  20 Cc: Peter Zijlstra <peterz@infradead.org>
  21 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  22 Cc: Masami Hiramatsu <mhiramat@kernel.org>
  23 Cc: Thomas Gleixner <tglx@linutronix.de>
  24 Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
  25 Cc: Francis Deslauriers <francis.deslauriers@efficios.com>
  26 Cc: Oleg Nesterov <oleg@redhat.com>
  27 Cc: Alexei Starovoitov <ast@kernel.org>
  28 Cc: Steven Rostedt <rostedt@goodmis.org>
  29 Cc: Andy Lutomirski <luto@kernel.org>
  30 Cc: "H . Peter Anvin" <hpa@zytor.com>
  31 Cc: Yonghong Song <yhs@fb.com>
  32 Cc: Borislav Petkov <bp@suse.de>
  33 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  34 Cc: "David S . Miller" <davem@davemloft.net>
  35 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  36 Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
  37 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  38 ---
  39  tools/objtool/arch/x86/include/asm/insn.h |   18 ++++++++++++++++++
  40  1 file changed, 18 insertions(+)
  41
  42 --- a/tools/objtool/arch/x86/include/asm/insn.h
  43 +++ b/tools/objtool/arch/x86/include/asm/insn.h
  44 @@ -208,4 +208,22 @@ static inline int insn_offset_immediate(
  45         return insn_offset_displacement(insn) + insn->displacement.nbytes;
  46  }
  47
  48 +#define POP_SS_OPCODE 0x1f
  49 +#define MOV_SREG_OPCODE 0x8e
  50 +
  51 +/*
  52 + * Intel SDM Vol.3A 6.8.3 states;
  53 + * "Any single-step trap that would be delivered following the MOV to SS
  54 + * instruction or POP to SS instruction (because EFLAGS.TF is 1) is
  55 + * suppressed."
  56 + * This function returns true if @insn is MOV SS or POP SS. On these
  57 + * instructions, single stepping is suppressed.
  58 + */
  59 +static inline int insn_masking_exception(struct insn *insn)
  60 +{
  61 +       return insn->opcode.bytes[0] == POP_SS_OPCODE ||
  62 +               (insn->opcode.bytes[0] == MOV_SREG_OPCODE &&
  63 +                X86_MODRM_REG(insn->modrm.bytes[0]) == 2);
  64 +}
  65 +
  66  #endif /* _ASM_X86_INSN_H */