Andrew Cooper
2013-Feb-04 14:57 UTC
[PATCH v2] hvm: Allow triple fault to imply crash rather than reboot
While the triple fault action on native hardware will result in a system
reset, any modern operating system can and will make use of less violent
reboot methods. As a result, the most likely cause of a triple fault is a
fatal software bug.
This patch allows the toolstack to indicate that a triple fault should mean a
crash rather than a reboot. The default of reboot still remains the same.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
--
Changes since v1:
* "reboot" -> "reset"
* v->domain -> d
diff -r 5af4f2ab06f3 -r de5df9f5af1d xen/arch/x86/hvm/hvm.c
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -1233,9 +1233,14 @@ void hvm_hlt(unsigned long rflags)
void hvm_triple_fault(void)
{
struct vcpu *v = current;
+ struct domain *d = v->domain;
+ u8 reason = d->arch.hvm_domain.params[HVM_PARAM_TRIPLE_FAULT_CRASH]
+ ? SHUTDOWN_crash : SHUTDOWN_reboot;
+
gdprintk(XENLOG_INFO, "Triple fault on VCPU%d - "
- "invoking HVM system reset.\n", v->vcpu_id);
- domain_shutdown(v->domain, SHUTDOWN_reboot);
+ "invoking HVM system %s.\n", v->vcpu_id,
+ reason == SHUTDOWN_crash ? "crash" : "reset");
+ domain_shutdown(d, reason);
}
void hvm_inject_trap(struct hvm_trap *trap)
diff -r 5af4f2ab06f3 -r de5df9f5af1d xen/include/public/hvm/params.h
--- a/xen/include/public/hvm/params.h
+++ b/xen/include/public/hvm/params.h
@@ -142,6 +142,9 @@
#define HVM_PARAM_ACCESS_RING_PFN 28
#define HVM_PARAM_SHARING_RING_PFN 29
-#define HVM_NR_PARAMS 31
+/* Boolean: Should a triple fault imply crash rather than reboot? */
+#define HVM_PARAM_TRIPLE_FAULT_CRASH 31
+
+#define HVM_NR_PARAMS 32
#endif /* __XEN_PUBLIC_HVM_PARAMS_H__ */