LoongArch: KVM: Fix "unreliable stack" for kvm_exc_entry

commit b323a441da602dfdfc24f30d3190cac786ffebf2 upstream.

Insert the appropriate UNWIND hint into the kvm_exc_entry assembly
function to guide the generation of correct ORC table entries, thereby
solving the timeout problem ("unreliable stack") while loading the
livepatch-sample module on a physical machine running virtual machines
with multiple vcpus.

Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/loongarch/kvm/switch.S b/arch/loongarch/kvm/switch.S
index 1d3ba7190154dc82c660dff80d6176dad8ff36c6..936e4ae3e408592480a6c36be2ab79b64a867ba3 100644 (file)
--- a/arch/loongarch/kvm/switch.S
+++ b/arch/loongarch/kvm/switch.S
@@ -111,7 +111,7 @@
        .p2align PAGE_SHIFT
        .cfi_sections   .debug_frame
 SYM_CODE_START(kvm_exc_entry)
-       UNWIND_HINT_UNDEFINED
+       UNWIND_HINT_END_OF_STACK
        csrwr   a2,   KVM_TEMP_KS
        csrrd   a2,   KVM_VCPU_KS
        addi.d  a2,   a2, KVM_VCPU_ARCH