summaryrefslogtreecommitdiffstats
path: root/arch/x86
diff options
context:
space:
mode:
authorVitaly Kuznetsov <vkuznets@redhat.com>2015-09-25 11:59:52 +0200
committerDavid Vrabel <david.vrabel@citrix.com>2015-09-28 15:48:52 +0200
commit0b34a166f291d255755be46e43ed5497cdd194f2 (patch)
tree5b7a2348190f566b74b3de41af90240887773529 /arch/x86
parentxen/x86: Don't try to write syscall-related MSRs for PV guests (diff)
downloadlinux-0b34a166f291d255755be46e43ed5497cdd194f2.tar.xz
linux-0b34a166f291d255755be46e43ed5497cdd194f2.zip
x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
Currently there is a number of issues preventing PVHVM Xen guests from doing successful kexec/kdump: - Bound event channels. - Registered vcpu_info. - PIRQ/emuirq mappings. - shared_info frame after XENMAPSPACE_shared_info operation. - Active grant mappings. Basically, newly booted kernel stumbles upon already set up Xen interfaces and there is no way to reestablish them. In Xen-4.7 a new feature called 'soft reset' is coming. A guest performing kexec/kdump operation is supposed to call SCHEDOP_shutdown hypercall with SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor (with some help from toolstack) will do full domain cleanup (but keeping its memory and vCPU contexts intact) returning the guest to the state it had when it was first booted and thus allowing it to start over. Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is probably OK as by default all unknown shutdown reasons cause domain destroy with a message in toolstack log: 'Unknown shutdown reason code 5. Destroying domain.' which gives a clue to what the problem is and eliminates false expectations. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/xen/enlighten.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 1f1dbd2949a4..993b7a71386d 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -33,6 +33,10 @@
#include <linux/memblock.h>
#include <linux/edd.h>
+#ifdef CONFIG_KEXEC_CORE
+#include <linux/kexec.h>
+#endif
+
#include <xen/xen.h>
#include <xen/events.h>
#include <xen/interface/xen.h>
@@ -1808,6 +1812,21 @@ static struct notifier_block xen_hvm_cpu_notifier = {
.notifier_call = xen_hvm_cpu_notify,
};
+#ifdef CONFIG_KEXEC_CORE
+static void xen_hvm_shutdown(void)
+{
+ native_machine_shutdown();
+ if (kexec_in_progress)
+ xen_reboot(SHUTDOWN_soft_reset);
+}
+
+static void xen_hvm_crash_shutdown(struct pt_regs *regs)
+{
+ native_machine_crash_shutdown(regs);
+ xen_reboot(SHUTDOWN_soft_reset);
+}
+#endif
+
static void __init xen_hvm_guest_init(void)
{
if (xen_pv_domain())
@@ -1827,6 +1846,10 @@ static void __init xen_hvm_guest_init(void)
x86_init.irqs.intr_init = xen_init_IRQ;
xen_hvm_init_time_ops();
xen_hvm_init_mmu_ops();
+#ifdef CONFIG_KEXEC_CORE
+ machine_ops.shutdown = xen_hvm_shutdown;
+ machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
+#endif
}
#endif