Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

lguest: fix on Intel when KVM loaded (unhandled trap 13)

Browse source 
When KVM is loaded, and hence VT set up, the vmcall instruction in an
lguest guest causes a #GP, not #UD.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rusty Russell 2009-05-26 20:54:41 +09:30 committed by Linus Torvalds
parent ab2b7ebaad
commit 564346224d
1 changed files with 10 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
drivers/lguest/x86/core.c
View file

@ -358,6 +358,16 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu)
if (emulate_insn(cpu))
return;
}
/* If KVM is active, the vmcall instruction triggers a
* General Protection Fault. Normally it triggers an
* invalid opcode fault (6): */
case 6:
/* We need to check if ring == GUEST_PL and
* faulting instruction == vmcall. */
if (is_hypercall(cpu)) {
rewrite_hypercall(cpu);
return;
}
break;
case 14: /* We've intercepted a Page Fault. */
/* The Guest accessed a virtual address that wasn't mapped.
@ -403,15 +413,6 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu)
* up the pointer now to indicate a hypercall is pending. */
cpu->hcall = (struct hcall_args *)cpu->regs;
return;
case 6:
/* kvm hypercalls trigger an invalid opcode fault (6).
* We need to check if ring == GUEST_PL and
* faulting instruction == vmcall. */
if (is_hypercall(cpu)) {
rewrite_hypercall(cpu);
return;
}
break;
}
/* We didn't handle the trap, so it needs to go to the Guest. */