MFC r273666.

Don't pass the 'error' return from an I/O port handler directly to vm_run().
This commit is contained in:
neel 2014-10-29 01:54:37 +00:00
parent f3c02a878d
commit 9221e1200a

View File

@ -106,15 +106,14 @@ emulate_inout_port(struct vm *vm, int vcpuid, struct vm_exit *vmexit,
uint32_t mask, val;
int error;
error = 0;
*retu = true;
if (vmexit->u.inout.port >= MAX_IOPORTS)
goto done;
handler = ioport_handler[vmexit->u.inout.port];
if (handler == NULL)
goto done;
/*
* If there is no handler for the I/O port then punt to userspace.
*/
if (vmexit->u.inout.port >= MAX_IOPORTS ||
(handler = ioport_handler[vmexit->u.inout.port]) == NULL) {
*retu = true;
return (0);
}
mask = vie_size2mask(vmexit->u.inout.bytes);
@ -124,20 +123,27 @@ emulate_inout_port(struct vm *vm, int vcpuid, struct vm_exit *vmexit,
error = (*handler)(vm, vcpuid, vmexit->u.inout.in,
vmexit->u.inout.port, vmexit->u.inout.bytes, &val);
if (!error) {
*retu = false;
if (vmexit->u.inout.in) {
vmexit->u.inout.eax &= ~mask;
vmexit->u.inout.eax |= val & mask;
error = vm_set_register(vm, vcpuid,
VM_REG_GUEST_RAX, vmexit->u.inout.eax);
KASSERT(error == 0, ("emulate_ioport: error %d "
"setting guest rax register", error));
}
if (error) {
/*
* The value returned by this function is also the return value
* of vm_run(). This needs to be a positive number otherwise it
* can be interpreted as a "pseudo-error" like ERESTART.
*
* Enforce this by mapping all errors to EIO.
*/
return (EIO);
}
done:
return (error);
if (vmexit->u.inout.in) {
vmexit->u.inout.eax &= ~mask;
vmexit->u.inout.eax |= val & mask;
error = vm_set_register(vm, vcpuid, VM_REG_GUEST_RAX,
vmexit->u.inout.eax);
KASSERT(error == 0, ("emulate_ioport: error %d setting guest "
"rax register", error));
}
*retu = false;
return (0);
}
static int