LLVM's assembler doesn't accept the short form inl (%%dx) instruction, but instead insists on the output register to be explicitly specified:
<inline asm>:1:7: error: invalid operand for instruction inl (%dx) ^ LLVM ERROR: Error parsing inline asm Use the full form of the instruction to fix the build. Signed-off-by: Sami Tolvanen <samitolva...@google.com> --- arch/x86/kernel/cpu/vmware.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c index 9735139cfdf8..46d732696c1c 100644 --- a/arch/x86/kernel/cpu/vmware.c +++ b/arch/x86/kernel/cpu/vmware.c @@ -49,7 +49,7 @@ #define VMWARE_CMD_VCPU_RESERVED 31 #define VMWARE_PORT(cmd, eax, ebx, ecx, edx) \ - __asm__("inl (%%dx)" : \ + __asm__("inl (%%dx), %%eax" : \ "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ "a"(VMWARE_HYPERVISOR_MAGIC), \ "c"(VMWARE_CMD_##cmd), \ -- 2.23.0.581.g78d2f28ef7-goog