From 0f4ef8a3bf784f250abc7d0155ae4e9fa22d8210 Mon Sep 17 00:00:00 2001
From: Ganesh Goudar <ganeshgr@linux.ibm.com>
Date: Fri, 7 Jan 2022 19:44:27 +0530
Subject: [PATCH] selftests/powerpc: Add test for real address error handling

Add test for real address or control memory address access
error handling, using NX-GZIP engine.

The error is injected by accessing the control memory address
using illegal instruction, on successful handling the process
attempting to access control memory address using illegal
instruction receives SIGBUS.

Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220107141428.67862-2-ganeshgr@linux.ibm.com
---
 tools/testing/selftests/powerpc/Makefile      |  3 +-
 tools/testing/selftests/powerpc/mce/Makefile  |  7 ++
 .../selftests/powerpc/mce/inject-ra-err.c     | 65 +++++++++++++++++++
 tools/testing/selftests/powerpc/mce/vas-api.h |  1 +
 4 files changed, 75 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/powerpc/mce/Makefile
 create mode 100644 tools/testing/selftests/powerpc/mce/inject-ra-err.c
 create mode 120000 tools/testing/selftests/powerpc/mce/vas-api.h

diff --git a/tools/testing/selftests/powerpc/Makefile b/tools/testing/selftests/powerpc/Makefile
index 0830e63818c1e..4830372d74169 100644
--- a/tools/testing/selftests/powerpc/Makefile
+++ b/tools/testing/selftests/powerpc/Makefile
@@ -31,7 +31,8 @@ SUB_DIRS = alignment		\
 	   vphn         \
 	   math		\
 	   ptrace	\
-	   security
+	   security	\
+	   mce
 
 endif
 
diff --git a/tools/testing/selftests/powerpc/mce/Makefile b/tools/testing/selftests/powerpc/mce/Makefile
new file mode 100644
index 0000000000000..2424513982d9b
--- /dev/null
+++ b/tools/testing/selftests/powerpc/mce/Makefile
@@ -0,0 +1,7 @@
+#SPDX-License-Identifier: GPL-2.0-or-later
+
+TEST_GEN_PROGS := inject-ra-err
+
+include ../../lib.mk
+
+$(TEST_GEN_PROGS): ../harness.c
diff --git a/tools/testing/selftests/powerpc/mce/inject-ra-err.c b/tools/testing/selftests/powerpc/mce/inject-ra-err.c
new file mode 100644
index 0000000000000..94323c34d9a6a
--- /dev/null
+++ b/tools/testing/selftests/powerpc/mce/inject-ra-err.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "vas-api.h"
+#include "utils.h"
+
+static bool faulted;
+
+static void sigbus_handler(int n, siginfo_t *info, void *ctxt_v)
+{
+	ucontext_t *ctxt = (ucontext_t *)ctxt_v;
+	struct pt_regs *regs = ctxt->uc_mcontext.regs;
+
+	faulted = true;
+	regs->nip += 4;
+}
+
+static int test_ra_error(void)
+{
+	struct vas_tx_win_open_attr attr;
+	int fd, *paste_addr;
+	char *devname = "/dev/crypto/nx-gzip";
+	struct sigaction act = {
+		.sa_sigaction = sigbus_handler,
+		.sa_flags = SA_SIGINFO,
+	};
+
+	memset(&attr, 0, sizeof(attr));
+	attr.version = 1;
+	attr.vas_id = 0;
+
+	SKIP_IF(access(devname, F_OK));
+
+	fd = open(devname, O_RDWR);
+	FAIL_IF(fd < 0);
+	FAIL_IF(ioctl(fd, VAS_TX_WIN_OPEN, &attr) < 0);
+	FAIL_IF(sigaction(SIGBUS, &act, NULL) != 0);
+
+	paste_addr = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0ULL);
+
+	/* The following assignment triggers exception */
+	mb();
+	*paste_addr = 1;
+	mb();
+
+	FAIL_IF(!faulted);
+
+	return 0;
+}
+
+int main(void)
+{
+	return test_harness(test_ra_error, "inject-ra-err");
+}
+
diff --git a/tools/testing/selftests/powerpc/mce/vas-api.h b/tools/testing/selftests/powerpc/mce/vas-api.h
new file mode 120000
index 0000000000000..1455c1bcd3517
--- /dev/null
+++ b/tools/testing/selftests/powerpc/mce/vas-api.h
@@ -0,0 +1 @@
+../../../../../arch/powerpc/include/uapi/asm/vas-api.h
\ No newline at end of file
-- 
2.30.2