From: Michael Ellerman <m...@ellerman.id.au>
This adds a set of test cases to test the behaviour of
copy_tofrom_user when exceptions are encountered accessing the
source or destination. Currently, copy_tofrom_user does not always
copy as many bytes as possible when an exception occurs on a store
to the destination, and that is reflected in failures in these tests.
Based on a test program from Anton Blanchard.
[pau...@ozlabs.org - test all three paths, wrote commit description,
made EX_TABLE create an exception table.]
Signed-off-by: Paul Mackerras <pau...@ozlabs.org>
---
.../testing/selftests/powerpc/copyloops/.gitignore | 3 +
tools/testing/selftests/powerpc/copyloops/Makefile | 12 +-
.../selftests/powerpc/copyloops/asm/ppc_asm.h | 27 ++---
.../powerpc/copyloops/copy_tofrom_user_reference.S | 24 ++++
.../selftests/powerpc/copyloops/exc_validate.c | 124 +++++++++++++++++++++
tools/testing/selftests/powerpc/copyloops/stubs.S | 19 ++++
6 files changed, 188 insertions(+), 21 deletions(-)
create mode 100644
tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S
create mode 100644 tools/testing/selftests/powerpc/copyloops/exc_validate.c
create mode 100644 tools/testing/selftests/powerpc/copyloops/stubs.S
diff --git a/tools/testing/selftests/powerpc/copyloops/.gitignore
b/tools/testing/selftests/powerpc/copyloops/.gitignore
index bc6c4ba..ce12cd0 100644
--- a/tools/testing/selftests/powerpc/copyloops/.gitignore
+++ b/tools/testing/selftests/powerpc/copyloops/.gitignore
@@ -8,3 +8,6 @@ memcpy_64_t1
memcpy_64_t2
memcpy_power7_t0
memcpy_power7_t1
+copyuser_64_exc_t0
+copyuser_64_exc_t1
+copyuser_64_exc_t2
diff --git a/tools/testing/selftests/powerpc/copyloops/Makefile
b/tools/testing/selftests/powerpc/copyloops/Makefile
index 9a5b0d2..9da0010 100644
--- a/tools/testing/selftests/powerpc/copyloops/Makefile
+++ b/tools/testing/selftests/powerpc/copyloops/Makefile
@@ -11,9 +11,10 @@ ASFLAGS = $(CFLAGS) -Wa,-mpower4
TEST_GEN_PROGS := copyuser_64_t0 copyuser_64_t1 copyuser_64_t2 \
copyuser_p7_t0 copyuser_p7_t1 \
memcpy_64_t0 memcpy_64_t1 memcpy_64_t2 \
- memcpy_p7_t0 memcpy_p7_t1
+ memcpy_p7_t0 memcpy_p7_t1 \
+ copyuser_64_exc_t0 copyuser_64_exc_t1 copyuser_64_exc_t2
-EXTRA_SOURCES := validate.c ../harness.c
+EXTRA_SOURCES := validate.c ../harness.c stubs.S
include ../../lib.mk
@@ -41,3 +42,10 @@ $(OUTPUT)/memcpy_p7_t%: memcpy_power7.S $(EXTRA_SOURCES)
-D COPY_LOOP=test_memcpy_power7 \
-D SELFTEST_CASE=$(subst memcpy_p7_t,,$(notdir $@)) \
-o $@ $^
+
+$(OUTPUT)/copyuser_64_exc_t%: copyuser_64.S exc_validate.c ../harness.c \
+ copy_tofrom_user_reference.S stubs.S
+ $(CC) $(CPPFLAGS) $(CFLAGS) \
+ -D COPY_LOOP=test___copy_tofrom_user_base \
+ -D SELFTEST_CASE=$(subst copyuser_64_exc_t,,$(notdir $@)) \
+ -o $@ $^
diff --git a/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h
b/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h
index 91bc403..0605df8 100644
--- a/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h
+++ b/tools/testing/selftests/powerpc/copyloops/asm/ppc_asm.h
@@ -1,4 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __SELFTESTS_POWERPC_PPC_ASM_H
+#define __SELFTESTS_POWERPC_PPC_ASM_H
#include <ppc-asm.h>
#define CONFIG_ALTIVEC
@@ -26,25 +28,10 @@
#define PPC_MTOCRF(A, B) mtocrf A, B
-#define EX_TABLE(x, y)
-
-FUNC_START(enter_vmx_usercopy)
- li r3,1
- blr
-
-FUNC_START(exit_vmx_usercopy)
- li r3,0
- blr
-
-FUNC_START(enter_vmx_ops)
- li r3,1
- blr
-
-FUNC_START(exit_vmx_ops)
- blr
-
-FUNC_START(__copy_tofrom_user_base)
- blr
+#define EX_TABLE(x, y) \
+ .section __ex_table,"a"; \
+ .8byte x, y; \
+ .previous
#define BEGIN_FTR_SECTION .if test_feature
#define FTR_SECTION_ELSE .else
@@ -56,3 +43,5 @@ FUNC_START(__copy_tofrom_user_base)
/* Default to taking the first of any alternative feature sections */
test_feature = 1
+
+#endif /* __SELFTESTS_POWERPC_PPC_ASM_H */
diff --git
a/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S
b/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S
new file mode 100644
index 0000000..3363b86
--- /dev/null
+++ b/tools/testing/selftests/powerpc/copyloops/copy_tofrom_user_reference.S
@@ -0,0 +1,24 @@
+#include <asm/ppc_asm.h>
+
+_GLOBAL(copy_tofrom_user_reference)
+ cmpdi r5,0
+ beq 4f
+
+ mtctr r5
+
+1: lbz r6,0(r4)
+2: stb r6,0(r3)
+ addi r3,r3,1
+ addi r4,r4,1
+ bdnz 1b
+
+3: mfctr r3
+ blr
+
+4: mr r3,r5
+ blr
+
+.section __ex_table,"a"
+ .llong 1b,3b
+ .llong 2b,3b
+.text
diff --git a/tools/testing/selftests/powerpc/copyloops/exc_validate.c
b/tools/testing/selftests/powerpc/copyloops/exc_validate.c
new file mode 100644
index 0000000..c896ea9
--- /dev/null
+++ b/tools/testing/selftests/powerpc/copyloops/exc_validate.c
@@ -0,0 +1,124 @@
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include "utils.h"
+
+extern char __start___ex_table[];
+extern char __stop___ex_table[];
+
+#if defined(__powerpc64__)
+#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.gp_regs[PT_NIP]
+#elif defined(__powerpc__)
+#define UCONTEXT_NIA(UC) (UC)->uc_mcontext.uc_regs->gregs[PT_NIP]
+#else
+#error implement UCONTEXT_NIA
+#endif
+
+static void segv_handler(int signr, siginfo_t *info, void *ptr)
+{
+ ucontext_t *uc = (ucontext_t *)ptr;
+ unsigned long addr = (unsigned long)info->si_addr;
+ unsigned long *ip = &UCONTEXT_NIA(uc);
+ unsigned long *ex_p = (unsigned long *)__start___ex_table;
+
+ while (ex_p < (unsigned long *)__stop___ex_table) {
+ unsigned long insn, fixup;
+
+ insn = *ex_p++;
+ fixup = *ex_p++;
+
+ if (insn == *ip) {
+ *ip = fixup;
+ return;
+ }
+ }
+
+ printf("No exception table match for NIA %lx ADDR %lx\n", *ip, addr);
+ abort();
+}
+
+static void setup_segv_handler(void)
+{
+ struct sigaction action;
+
+ memset(&action, 0, sizeof(action));
+ action.sa_sigaction = segv_handler;
+ action.sa_flags = SA_SIGINFO;
+ sigaction(SIGSEGV, &action, NULL);
+}
+
+unsigned long COPY_LOOP(void *to, const void *from, unsigned long size);
+unsigned long test_copy_tofrom_user_reference(void *to, const void *from,
unsigned long size);
+
+static int total_passed;
+static int total_failed;
+
+static void do_one_test(char *dstp, char *srcp, unsigned long len)
+{
+ unsigned long got, expected;
+
+ got = COPY_LOOP(dstp, srcp, len);
+ expected = test_copy_tofrom_user_reference(dstp, srcp, len);
+
+ if (got != expected) {
+ total_failed++;
+ printf("FAIL from=%p to=%p len=%ld returned %ld, expected
%ld\n",
+ srcp, dstp, len, got, expected);
+ //abort();
+ } else
+ total_passed++;
+}
+
+//#define MAX_LEN 512
+#define MAX_LEN 16
+
+int test_copy_exception(void)
+{
+ int page_size;
+ static char *p, *q;
+ unsigned long src, dst, len;
+
+ page_size = getpagesize();
+ p = mmap(NULL, page_size * 2, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+
+ if (p == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ memset(p, 0, page_size);
+
+ setup_segv_handler();
+
+ if (mprotect(p + page_size, page_size, PROT_NONE)) {
+ perror("mprotect");
+ exit(1);
+ }
+
+ q = p + page_size - MAX_LEN;
+
+ for (src = 0; src < MAX_LEN; src++) {
+ for (dst = 0; dst < MAX_LEN; dst++) {
+ for (len = 0; len < MAX_LEN+1; len++) {
+ // printf("from=%p to=%p len=%ld\n", q+dst,
q+src, len);
+ do_one_test(q+dst, q+src, len);
+ }
+ }
+ }
+
+ printf("Totals:\n");
+ printf(" Pass: %d\n", total_passed);
+ printf(" Fail: %d\n", total_failed);
+
+ return 0;
+}
+
+int main(void)
+{
+ return test_harness(test_copy_exception, str(COPY_LOOP));
+}
diff --git a/tools/testing/selftests/powerpc/copyloops/stubs.S
b/tools/testing/selftests/powerpc/copyloops/stubs.S
new file mode 100644
index 0000000..ec8bcf2
--- /dev/null
+++ b/tools/testing/selftests/powerpc/copyloops/stubs.S
@@ -0,0 +1,19 @@
+#include <asm/ppc_asm.h>
+
+FUNC_START(enter_vmx_usercopy)
+ li r3,1
+ blr
+
+FUNC_START(exit_vmx_usercopy)
+ li r3,0
+ blr
+
+FUNC_START(enter_vmx_ops)
+ li r3,1
+ blr
+
+FUNC_START(exit_vmx_ops)
+ blr
+
+FUNC_START(__copy_tofrom_user_base)
+ blr
--
2.7.4
