IOMMU: add crash_shutdown iommu_op

The kdump kernel has problems booting with interrupt/dma
remapping enabled, so we need a new iommu_ops called
crash_shutdown which is basically suspend but doesn't
need to bother saving state.

Make sure that crash_shutdown is called on the kexec
path.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/xen/arch/x86/crash.c b/xen/arch/x86/crash.c
index 1fa7ef7db6..19508550df 100644
--- a/xen/arch/x86/crash.c
+++ b/xen/arch/x86/crash.c
@@ -77,6 +77,10 @@ static void nmi_shootdown_cpus(void)
         msecs--;
     }
 
+    /* Crash shutdown any IOMMU functionality as the crashdump kernel is not
+     * happy when booting if interrupt/dma remapping is still enabled */
+    iommu_crash_shutdown();
+
     __stop_this_cpu();
     disable_IO_APIC();
 }