Re: [v2 7/7] x86: Enable User-Mode Instruction Prevention

Hi Ricardo,

[auto build test WARNING on tip/auto-latest]
[also build test WARNING on next-20161223]
[cannot apply to tip/x86/core v4.9]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Ricardo-Neri/x86-enable-User-Mode-Instruction-Prevention/20161224-094338
config: x86_64-acpi-redef (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   arch/x86/kernel/umip.c: In function '__identify_insn':
>> arch/x86/kernel/umip.c:65:1: warning: control reaches end of non-void function [-Wreturn-type]
    }
    ^

vim +65 arch/x86/kernel/umip.c

78301541 Ricardo Neri 2016-12-23  49  			return UMIP_SGDT;
78301541 Ricardo Neri 2016-12-23  50  		case 1:
78301541 Ricardo Neri 2016-12-23  51  			return UMIP_SIDT;
78301541 Ricardo Neri 2016-12-23  52  		case 4:
78301541 Ricardo Neri 2016-12-23  53  			return UMIP_SMSW;
78301541 Ricardo Neri 2016-12-23  54  		default:
78301541 Ricardo Neri 2016-12-23  55  			return -EINVAL;
78301541 Ricardo Neri 2016-12-23  56  		}
78301541 Ricardo Neri 2016-12-23  57  	} else if (insn->opcode.bytes[1] == 0x0) {
78301541 Ricardo Neri 2016-12-23  58  		if (X86_MODRM_REG(insn->modrm.value) == 0)
78301541 Ricardo Neri 2016-12-23  59  			return UMIP_SLDT;
78301541 Ricardo Neri 2016-12-23  60  		else if (X86_MODRM_REG(insn->modrm.value) == 1)
78301541 Ricardo Neri 2016-12-23  61  			return UMIP_STR;
78301541 Ricardo Neri 2016-12-23  62  		else
78301541 Ricardo Neri 2016-12-23  63  			return -EINVAL;
78301541 Ricardo Neri 2016-12-23  64  	}
78301541 Ricardo Neri 2016-12-23 @65  }
78301541 Ricardo Neri 2016-12-23  66  
78301541 Ricardo Neri 2016-12-23  67  static int __emulate_umip_insn(struct insn *insn, enum umip_insn umip_inst,
78301541 Ricardo Neri 2016-12-23  68  			       unsigned char *data, int *data_size)
78301541 Ricardo Neri 2016-12-23  69  {
78301541 Ricardo Neri 2016-12-23  70  	unsigned long const *dummy_base_addr;
78301541 Ricardo Neri 2016-12-23  71  	unsigned short dummy_limit = 0;
78301541 Ricardo Neri 2016-12-23  72  	unsigned short dummy_value = 0;
78301541 Ricardo Neri 2016-12-23  73  

:::::: The code at line 65 was first introduced by commit
:::::: 7830154191c35fde49ef59c2b9328f6b32203be4 x86: Add emulation code for UMIP instructions

:::::: TO: Ricardo Neri <[email protected]>
:::::: CC: 0day robot <[email protected]>

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