diff options
Diffstat (limited to 'arch/x86/kernel/umip.c')
| -rw-r--r-- | arch/x86/kernel/umip.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index 576b47e7523d..d432f3824f0c 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -92,8 +92,8 @@ static const char * const umip_insns[5] = { #define umip_pr_err(regs, fmt, ...) \ umip_printk(regs, KERN_ERR, fmt, ##__VA_ARGS__) -#define umip_pr_warn(regs, fmt, ...) \ - umip_printk(regs, KERN_WARNING, fmt, ##__VA_ARGS__) +#define umip_pr_debug(regs, fmt, ...) \ + umip_printk(regs, KERN_DEBUG, fmt, ##__VA_ARGS__) /** * umip_printk() - Print a rate-limited message @@ -156,15 +156,26 @@ static int identify_insn(struct insn *insn) if (!insn->modrm.nbytes) return -EINVAL; - /* All the instructions of interest start with 0x0f. */ - if (insn->opcode.bytes[0] != 0xf) + /* The instructions of interest have 2-byte opcodes: 0F 00 or 0F 01. */ + if (insn->opcode.nbytes < 2 || insn->opcode.bytes[0] != 0xf) return -EINVAL; if (insn->opcode.bytes[1] == 0x1) { switch (X86_MODRM_REG(insn->modrm.value)) { case 0: + /* The reg form of 0F 01 /0 encodes VMX instructions. */ + if (X86_MODRM_MOD(insn->modrm.value) == 3) + return -EINVAL; + return UMIP_INST_SGDT; case 1: + /* + * The reg form of 0F 01 /1 encodes MONITOR/MWAIT, + * STAC/CLAC, and ENCLS. + */ + if (X86_MODRM_MOD(insn->modrm.value) == 3) + return -EINVAL; + return UMIP_INST_SIDT; case 4: return UMIP_INST_SMSW; @@ -361,10 +372,10 @@ bool fixup_umip_exception(struct pt_regs *regs) if (umip_inst < 0) return false; - umip_pr_warn(regs, "%s instruction cannot be used by applications.\n", + umip_pr_debug(regs, "%s instruction cannot be used by applications.\n", umip_insns[umip_inst]); - umip_pr_warn(regs, "For now, expensive software emulation returns the result.\n"); + umip_pr_debug(regs, "For now, expensive software emulation returns the result.\n"); if (emulate_umip_insn(&insn, umip_inst, dummy_data, &dummy_data_size, user_64bit_mode(regs))) |