Mailing List Archive

Avoid xen crash if there is no VMX support. If a platform
# HG changeset patch
# User kaf24@firebug.cl.cam.ac.uk
# Node ID 02cfa3beabba1de2b6dc864a71d10f0776c7aa99
# Parent 4299f983e8fe19187873062e1e2da32933f88292
Avoid xen crash if there is no VMX support. If a platform
doesn't support VMX, creating VMX domain will crash xen
HV.

Signed-off-by: Xin Li <xin.b.li@intel.com>

diff -r 4299f983e8fe -r 02cfa3beabba tools/libxc/xc_vmx_build.c
--- a/tools/libxc/xc_vmx_build.c Fri Dec 30 16:02:30 2005
+++ b/tools/libxc/xc_vmx_build.c Fri Dec 30 16:07:34 2005
@@ -574,29 +574,6 @@
return -1;
}

-#define VMX_FEATURE_FLAG 0x20
-
-static int vmx_identify(void)
-{
- int eax, ecx;
-
- __asm__ __volatile__ (
-#if defined(__i386__)
- "push %%ebx; cpuid; pop %%ebx"
-#elif defined(__x86_64__)
- "push %%rbx; cpuid; pop %%rbx"
-#endif
- : "=a" (eax), "=c" (ecx)
- : "0" (1)
- : "dx");
-
- if (!(ecx & VMX_FEATURE_FLAG)) {
- return -1;
- }
-
- return 0;
-}
-
int xc_vmx_build(int xc_handle,
uint32_t domid,
int memsize,
@@ -613,10 +590,18 @@
unsigned long nr_pages;
char *image = NULL;
unsigned long image_size;
-
- if ( vmx_identify() < 0 )
- {
- PERROR("CPU doesn't support VMX Extensions");
+ xen_capabilities_info_t xen_caps;
+
+ if ( (rc = xc_version(xc_handle, XENVER_capabilities, &xen_caps)) != 0 )
+ {
+ PERROR("Failed to get xen version info");
+ goto error_out;
+ }
+
+ if ( !strstr(xen_caps, "hvm") )
+ {
+ PERROR("CPU doesn't support VMX Extensions or "
+ "CPU VMX Extensions are not turned on");
goto error_out;
}

diff -r 4299f983e8fe -r 02cfa3beabba tools/python/xen/xend/image.py
--- a/tools/python/xen/xend/image.py Fri Dec 30 16:02:30 2005
+++ b/tools/python/xen/xend/image.py Fri Dec 30 16:07:34 2005
@@ -188,6 +188,10 @@

def configure(self, imageConfig, deviceConfig):
ImageHandler.configure(self, imageConfig, deviceConfig)
+
+ info = xc.xeninfo()
+ if not 'hvm' in info['xen_caps']:
+ raise VmError("vmx: not an Intel VT platform, we stop creating!")

self.dmargs = self.parseDeviceModelArgs(imageConfig, deviceConfig)
self.device_model = sxp.child_value(imageConfig, 'device_model')
diff -r 4299f983e8fe -r 02cfa3beabba xen/arch/x86/domain.c
--- a/xen/arch/x86/domain.c Fri Dec 30 16:02:30 2005
+++ b/xen/arch/x86/domain.c Fri Dec 30 16:07:34 2005
@@ -35,7 +35,6 @@
#include <xen/console.h>
#include <xen/elf.h>
#include <asm/vmx.h>
-#include <asm/vmx_vmcs.h>
#include <asm/msr.h>
#include <asm/physdev.h>
#include <xen/kernel.h>
@@ -348,6 +347,8 @@
((c->user_regs.ss & 3) == 0) )
return -EINVAL;
}
+ else if ( !hvm_enabled )
+ return -EINVAL;

clear_bit(_VCPUF_fpu_initialised, &v->vcpu_flags);
if ( c->flags & VGCF_I387_VALID )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@lists.xensource.com
http://lists.xensource.com/xen-changelog