With the new toolchain baseline, we can make use of asm goto() in certain
places, and the VMXON invocation is one example.
This removes the logic to set up rc (including a fixup section where bactraces
have no connection to the invoking function), the logic to decode it, and the
default case which was dead but in a way the compiler couldn't prove
previously.
No functional change.
Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com>
---
CC: Jan Beulich <jbeul...@suse.com>
CC: Roger Pau Monné <roger....@citrix.com>
CC: dm...@proton.me
v2:
* Move error block to the end of the function.
Bloat-o-meter:
add/remove: 0/0 grow/shrink: 1/1 up/down: 13/-32 (-19)
Function old new delta
_vmx_cpu_up.cold 2460 2473 +13
_vmx_cpu_up 1803 1771 -32
---
xen/arch/x86/hvm/vmx/vmcs.c | 50 +++++++++++++-------------
xen/arch/x86/include/asm/hvm/vmx/vmx.h | 19 ----------
2 files changed, 26 insertions(+), 43 deletions(-)
diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index 0ba65becec1e..8e99e6f73062 100644
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -749,30 +749,15 @@ static int _vmx_cpu_up(bool bsp)
if ( bsp && (rc = vmx_cpu_up_prepare(cpu)) != 0 )
return rc;
- switch ( __vmxon(this_cpu(vmxon_region)) )
- {
- case -2: /* #UD or #GP */
- if ( bios_locked &&
- test_bit(X86_FEATURE_SMX, &boot_cpu_data.x86_capability) &&
- (!(eax & IA32_FEATURE_CONTROL_ENABLE_VMXON_OUTSIDE_SMX) ||
- !(eax & IA32_FEATURE_CONTROL_ENABLE_VMXON_INSIDE_SMX)) )
- {
- printk("CPU%d: VMXON failed: perhaps because of TXT settings "
- "in your BIOS configuration?\n", cpu);
- printk(" --> Disable TXT in your BIOS unless using a secure "
- "bootloader.\n");
- return -EINVAL;
- }
- /* fall through */
- case -1: /* CF==1 or ZF==1 */
- printk("CPU%d: unexpected VMXON failure\n", cpu);
- return -EINVAL;
- case 0: /* success */
- this_cpu(vmxon) = 1;
- break;
- default:
- BUG();
- }
+ asm goto ( "1: vmxon %[addr]\n\t"
+ "jbe %l[vmxon_fail]\n\t"
+ _ASM_EXTABLE(1b, %l[vmxon_fault])
+ :
+ : [addr] "m" (this_cpu(vmxon_region))
+ :
+ : vmxon_fail, vmxon_fault );
+
+ this_cpu(vmxon) = 1;
hvm_asid_init(cpu_has_vmx_vpid ? (1u << VMCS_VPID_WIDTH) : 0);
@@ -785,6 +770,23 @@ static int _vmx_cpu_up(bool bsp)
vmx_pi_per_cpu_init(cpu);
return 0;
+
+ vmxon_fault:
+ if ( bios_locked &&
+ test_bit(X86_FEATURE_SMX, &boot_cpu_data.x86_capability) &&
+ (!(eax & IA32_FEATURE_CONTROL_ENABLE_VMXON_OUTSIDE_SMX) ||
+ !(eax & IA32_FEATURE_CONTROL_ENABLE_VMXON_INSIDE_SMX)) )
+ {
+ printk("CPU%d: VMXON failed: perhaps because of TXT settings "
+ "in your BIOS configuration?\n", cpu);
+ printk(" --> Disable TXT in your BIOS unless using a secure "
+ "bootloader.\n");
+ return -EINVAL;
+ }
+
+ vmxon_fail:
+ printk("CPU%d: unexpected VMXON failure\n", cpu);
+ return -EINVAL;
}
int cf_check vmx_cpu_up(void)
diff --git a/xen/arch/x86/include/asm/hvm/vmx/vmx.h
b/xen/arch/x86/include/asm/hvm/vmx/vmx.h
index 843f8591b9cf..7c6ba7340744 100644
--- a/xen/arch/x86/include/asm/hvm/vmx/vmx.h
+++ b/xen/arch/x86/include/asm/hvm/vmx/vmx.h
@@ -559,25 +559,6 @@ static inline void __vmxoff(void)
: : : "memory" );
}
-static inline int __vmxon(u64 addr)
-{
- int rc;
-
- asm volatile (
- "1: " VMXON_OPCODE MODRM_EAX_06 "\n"
- " setna %b0 ; neg %0\n" /* CF==1 or ZF==1 --> rc = -1 */
- "2:\n"
- ".section .fixup,\"ax\"\n"
- "3: sub $2,%0 ; jmp 2b\n" /* #UD or #GP --> rc = -2 */
- ".previous\n"
- _ASM_EXTABLE(1b, 3b)
- : "=q" (rc)
- : "0" (0), "a" (&addr)
- : "memory");
-
- return rc;
-}
-
int cf_check vmx_guest_x86_mode(struct vcpu *v);
unsigned int vmx_get_cpl(void);
--
2.39.5
