From: Andrew Cooper Date: Fri, 9 Jan 2015 16:27:04 +0000 (+0100) Subject: hvm/vmx: WRITE_MSR() macro hygene X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~3958 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=463a991e51835ced8d440d37959d5bfc1f79417b;p=xen.git hvm/vmx: WRITE_MSR() macro hygene Use the standard "do { } while ( 0 )" semantics, and don't hide the break statement, incase this macro wants to be used anywhere outside of a switch. No functional change, but it is now clear that long_mode_do_msr_write() doesn't have fallthough for the STAR, LSTAR and SYSCALL_MASK cases. Signed-off-by: Andrew Cooper Reviewed-by: Tim Deegan Acked-by: Kevin Tian --- diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index f2554d68d2..522892f5e0 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -152,12 +152,12 @@ void vmx_save_host_msrs(void) rdmsrl(msr_index[i], host_msr_state->msrs[i]); } -#define WRITE_MSR(address) \ +#define WRITE_MSR(address) do { \ guest_msr_state->msrs[VMX_INDEX_MSR_ ## address] = msr_content; \ set_bit(VMX_INDEX_MSR_ ## address, &guest_msr_state->flags); \ wrmsrl(MSR_ ## address, msr_content); \ set_bit(VMX_INDEX_MSR_ ## address, &host_msr_state->flags); \ - break + } while ( 0 ) static enum handler_return long_mode_do_msr_read(unsigned int msr, uint64_t *msr_content) @@ -232,11 +232,13 @@ long_mode_do_msr_write(unsigned int msr, uint64_t msr_content) case MSR_STAR: WRITE_MSR(STAR); + break; case MSR_LSTAR: if ( !is_canonical_address(msr_content) ) goto uncanonical_address; WRITE_MSR(LSTAR); + break; case MSR_CSTAR: if ( !is_canonical_address(msr_content) ) @@ -246,6 +248,7 @@ long_mode_do_msr_write(unsigned int msr, uint64_t msr_content) case MSR_SYSCALL_MASK: WRITE_MSR(SYSCALL_MASK); + break; default: return HNDL_unhandled;