[jcmvbkbc-xtensa:pr/24 1/1] arch/x86/kvm/emulate.c:1741:2: warning: '/*' within block comment

[kernel test robot <lkp@intel.com>]

tree:   https://github.com/jcmvbkbc/linux-xtensa pr/24
head:   dcd699a99ce2f40e50263e0ec438e3b57b133598
commit: dcd699a99ce2f40e50263e0ec438e3b57b133598 [1/1] Fix potential vulnerability in cloned code (arch/x86/kvm/emulate.c)
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20251220/202512202203.DAeqyrft-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251220/202512202203.DAeqyrft-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512202203.DAeqyrft-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/x86/kvm/emulate.c:1741:2: warning: '/*' within block comment [-Wcomment]
    1741 |         /*
         |         ^
   arch/x86/kvm/emulate.c:1759:4: error: expected expression
    1759 |          */
         |           ^
   arch/x86/kvm/emulate.c:1760:2: error: expected expression
    1760 |         if (seg == VCPU_SREG_SS && selector == 3 &&
         |         ^
   1 warning and 2 errors generated.


vim +1741 arch/x86/kvm/emulate.c

dde7e6d12a9ef9 Avi Kivity    2010-07-29  1733  
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1734  static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1735  				   u16 selector, int seg)
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1736  {
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1737  	u8 cpl = ctxt->ops->cpl(ctxt);
33ab91103b3415 Paolo Bonzini 2017-01-12  1738  
dcd699a99ce2f4 hungkien05    2025-12-17  1739  
dcd699a99ce2f4 hungkien05    2025-12-17  1740  	/*
33ab91103b3415 Paolo Bonzini 2017-01-12 @1741  	/*
33ab91103b3415 Paolo Bonzini 2017-01-12  1742  	 * None of MOV, POP and LSS can load a NULL selector in CPL=3, but
dcd699a99ce2f4 hungkien05    2025-12-17  1743  	 * None of MOV, POP and LSS can load a NULL selector in CPL=3, but
dcd699a99ce2f4 hungkien05    2025-12-17  1744  	 * they can load it at CPL<3 (Intel's manual says only LSS can,
33ab91103b3415 Paolo Bonzini 2017-01-12  1745  	 * they can load it at CPL<3 (Intel's manual says only LSS can,
33ab91103b3415 Paolo Bonzini 2017-01-12  1746  	 * but it's wrong).
dcd699a99ce2f4 hungkien05    2025-12-17  1747  	 * but it's wrong).
dcd699a99ce2f4 hungkien05    2025-12-17  1748  	 *
33ab91103b3415 Paolo Bonzini 2017-01-12  1749  	 *
33ab91103b3415 Paolo Bonzini 2017-01-12  1750  	 * However, the Intel manual says that putting IST=1/DPL=3 in
dcd699a99ce2f4 hungkien05    2025-12-17  1751  	 * However, the Intel manual says that putting IST=1/DPL=3 in
dcd699a99ce2f4 hungkien05    2025-12-17  1752  	 * an interrupt gate will result in SS=3 (the AMD manual instead
33ab91103b3415 Paolo Bonzini 2017-01-12  1753  	 * an interrupt gate will result in SS=3 (the AMD manual instead
33ab91103b3415 Paolo Bonzini 2017-01-12  1754  	 * says it doesn't), so allow SS=3 in __load_segment_descriptor
dcd699a99ce2f4 hungkien05    2025-12-17  1755  	 * says it doesn't), so allow SS=3 in __load_segment_descriptor
dcd699a99ce2f4 hungkien05    2025-12-17  1756  	 * and only forbid it here.
33ab91103b3415 Paolo Bonzini 2017-01-12  1757  	 * and only forbid it here.
33ab91103b3415 Paolo Bonzini 2017-01-12  1758  	 */
dcd699a99ce2f4 hungkien05    2025-12-17  1759  	 */
dcd699a99ce2f4 hungkien05    2025-12-17  1760  	if (seg == VCPU_SREG_SS && selector == 3 &&
33ab91103b3415 Paolo Bonzini 2017-01-12  1761  	if (seg == VCPU_SREG_SS && selector == 3 &&
33ab91103b3415 Paolo Bonzini 2017-01-12  1762  	    ctxt->mode == X86EMUL_MODE_PROT64)
dcd699a99ce2f4 hungkien05    2025-12-17  1763  	    ctxt->mode == X86EMUL_MODE_PROT64)
dcd699a99ce2f4 hungkien05    2025-12-17  1764  		return emulate_exception(ctxt, GP_VECTOR, 0, true);
33ab91103b3415 Paolo Bonzini 2017-01-12  1765  		return emulate_exception(ctxt, GP_VECTOR, 0, true);
33ab91103b3415 Paolo Bonzini 2017-01-12  1766  
dcd699a99ce2f4 hungkien05    2025-12-17  1767  
3dc4bc4f6b9265 Nadav Amit    2014-12-25  1768  	return __load_segment_descriptor(ctxt, selector, seg, cpl,
3dc4bc4f6b9265 Nadav Amit    2014-12-25  1769  					 X86_TRANSFER_NONE, NULL);
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1770  }
2356aaeb2f58f4 Paolo Bonzini 2014-05-15  1771  

:::::: The code at line 1741 was first introduced by commit
:::::: 33ab91103b3415e12457e3104f0e4517ce12d0f3 KVM: x86: fix emulation of "MOV SS, null selector"

:::::: TO: Paolo Bonzini <pbonzini@redhat.com>
:::::: CC: Paolo Bonzini <pbonzini@redhat.com>

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