Reading/writing unimplemented IOCSR on real LoongArch hardware doesn't
trigger any exceptions, instead, reading always results in zero and
writing is simply ignored.
Real-world applications, like memtest86plus, depend on the behavior to
run. However, since commit f2e61edb2946 ("hw/loongarch/virt: Use
MemTxAttrs interface for misc ops") which adds a call to
g_assert_not_reached() in the path of handling unimplemented IOCSRs,
QEMU would abort in the case.
Replace the assertion with qemu_log_mask(LOG_UNIMP, ...), so these
applications could run. It's still possible to examine unimplemented
IOCSR access through "-d unimp" command line arguments.
Fixes: f2e61edb2946 ("hw/loongarch/virt: Use MemTxAttrs interface for misc ops")
Signed-off-by: Yao Zi <[email protected]>
---
hw/loongarch/virt.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index 49434ad1828b..8d7da5fac550 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -46,6 +46,7 @@
#include "hw/block/flash.h"
#include "hw/virtio/virtio-iommu.h"
#include "qemu/error-report.h"
+#include "qemu/log.h"
#include "kvm/kvm_loongarch.h"
static void virt_get_dmsi(Object *obj, Visitor *v, const char *name,
@@ -622,7 +623,9 @@ static MemTxResult virt_iocsr_misc_write(void *opaque,
hwaddr addr,
features, attrs, NULL);
break;
default:
- g_assert_not_reached();
+ qemu_log_mask(LOG_UNIMP, "%s: Unimplemented IOCSR 0x%" HWADDR_PRIx
"\n",
+ __func__, addr);
+ break;
}
return MEMTX_OK;
@@ -680,7 +683,9 @@ static MemTxResult virt_iocsr_misc_read(void *opaque,
hwaddr addr,
}
break;
default:
- g_assert_not_reached();
+ qemu_log_mask(LOG_UNIMP, "%s: Unimplemented IOCSR 0x%" HWADDR_PRIx
"\n",
+ __func__, addr);
+ break;
}
*data = ret;
--
2.51.2
