Re: [kvm-devel] [PATCH] KVM: Avoid using vmx instruction directly
From: Arnd Bergmann
Date: Thu Nov 09 2006 - 08:30:20 EST
On Thursday 09 November 2006 12:08, Avi Kivity wrote:
> Index: linux-2.6/drivers/kvm/kvm_main.c
> ===================================================================
> --- linux-2.6.orig/drivers/kvm/kvm_main.c
> +++ linux-2.6/drivers/kvm/kvm_main.c
> @@ -369,8 +369,8 @@ static void vmcs_clear(struct vmcs *vmcs
> u64 phys_addr = __pa(vmcs);
> u8 error;
>
> - asm volatile ("vmclear %1; setna %0"
> - : "=m"(error) : "m"(phys_addr) : "cc", "memory" );
> + asm volatile (ASM_VMX_VMCLEAR_RAX "; setna %0"
> + : "=g"(error) : "a"(&phys_addr) : "cc", "memory" );
> if (error)
> printk(KERN_ERR "kvm: vmclear fail: %p/%llx\n",
> vmcs, phys_addr);
I'm not an expert on inline assembly, but don't you need an extra
'"m" (phys_addr)' to make sure that gcc actually puts the variable
on the stack instead of passing a NULL pointer as '"a"(&phys_addr)'?
Arnd <><
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/