Merge branch 'fixes' into next

Merge our fixes branch, in particular to bring in the changes for the
entry/uaccess flush.

7 files changed, 265 insertions, 67 deletions

diff --git a/tools/testing/selftests/powerpc/include/utils.h b/tools/testing/selftests/powerpc/include/utils.h
index 052b5a775dc2..b7d188fc87c7 100644
--- a/tools/testing/selftests/powerpc/include/utils.h
+++ b/tools/testing/selftests/powerpc/include/utils.h
@@ -42,6 +42,11 @@ int perf_event_enable(int fd);
 int perf_event_disable(int fd);
 int perf_event_reset(int fd);
 
+struct perf_event_read {
+	__u64 nr;
+	__u64 l1d_misses;
+};
+
 #if !defined(__GLIBC_PREREQ) || !__GLIBC_PREREQ(2, 30)
 #include <unistd.h>
 #include <sys/syscall.h>
diff --git a/tools/testing/selftests/powerpc/security/.gitignore b/tools/testing/selftests/powerpc/security/.gitignore
index f795e06f5ae3..4257a1f156bb 100644
--- a/tools/testing/selftests/powerpc/security/.gitignore
+++ b/tools/testing/selftests/powerpc/security/.gitignore
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
 rfi_flush
+entry_flush
diff --git a/tools/testing/selftests/powerpc/security/Makefile b/tools/testing/selftests/powerpc/security/Makefile
index eadbbff50be6..f25e854fe370 100644
--- a/tools/testing/selftests/powerpc/security/Makefile
+++ b/tools/testing/selftests/powerpc/security/Makefile
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0+
 
-TEST_GEN_PROGS := rfi_flush spectre_v2
+TEST_GEN_PROGS := rfi_flush entry_flush spectre_v2
 top_srcdir = ../../../../..
 
 CFLAGS += -I../../../../../usr/include
@@ -11,3 +11,5 @@ $(TEST_GEN_PROGS): ../harness.c ../utils.c
 
 $(OUTPUT)/spectre_v2: CFLAGS += -m64
 $(OUTPUT)/spectre_v2: ../pmu/event.c branch_loops.S
+$(OUTPUT)/rfi_flush: flush_utils.c
+$(OUTPUT)/entry_flush: flush_utils.c
diff --git a/tools/testing/selftests/powerpc/security/entry_flush.c b/tools/testing/selftests/powerpc/security/entry_flush.c
new file mode 100644
index 000000000000..78cf914fa321
--- /dev/null
+++ b/tools/testing/selftests/powerpc/security/entry_flush.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * Copyright 2018 IBM Corporation.
+ */
+
+#define __SANE_USERSPACE_TYPES__
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <malloc.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "utils.h"
+#include "flush_utils.h"
+
+int entry_flush_test(void)
+{
+	char *p;
+	int repetitions = 10;
+	int fd, passes = 0, iter, rc = 0;
+	struct perf_event_read v;
+	__u64 l1d_misses_total = 0;
+	unsigned long iterations = 100000, zero_size = 24 * 1024;
+	unsigned long l1d_misses_expected;
+	int rfi_flush_orig;
+	int entry_flush, entry_flush_orig;
+
+	SKIP_IF(geteuid() != 0);
+
+	// The PMU event we use only works on Power7 or later
+	SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06));
+
+	if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_orig) < 0) {
+		perror("Unable to read powerpc/rfi_flush debugfs file");
+		SKIP_IF(1);
+	}
+
+	if (read_debugfs_file("powerpc/entry_flush", &entry_flush_orig) < 0) {
+		perror("Unable to read powerpc/entry_flush debugfs file");
+		SKIP_IF(1);
+	}
+
+	if (rfi_flush_orig != 0) {
+		if (write_debugfs_file("powerpc/rfi_flush", 0) < 0) {
+			perror("error writing to powerpc/rfi_flush debugfs file");
+			FAIL_IF(1);
+		}
+	}
+
+	entry_flush = entry_flush_orig;
+
+	fd = perf_event_open_counter(PERF_TYPE_RAW, /* L1d miss */ 0x400f0, -1);
+	FAIL_IF(fd < 0);
+
+	p = (char *)memalign(zero_size, CACHELINE_SIZE);
+
+	FAIL_IF(perf_event_enable(fd));
+
+	// disable L1 prefetching
+	set_dscr(1);
+
+	iter = repetitions;
+
+	/*
+	 * We expect to see l1d miss for each cacheline access when entry_flush
+	 * is set. Allow a small variation on this.
+	 */
+	l1d_misses_expected = iterations * (zero_size / CACHELINE_SIZE - 2);
+
+again:
+	FAIL_IF(perf_event_reset(fd));
+
+	syscall_loop(p, iterations, zero_size);
+
+	FAIL_IF(read(fd, &v, sizeof(v)) != sizeof(v));
+
+	if (entry_flush && v.l1d_misses >= l1d_misses_expected)
+		passes++;
+	else if (!entry_flush && v.l1d_misses < (l1d_misses_expected / 2))
+		passes++;
+
+	l1d_misses_total += v.l1d_misses;
+
+	while (--iter)
+		goto again;
+
+	if (passes < repetitions) {
+		printf("FAIL (L1D misses with entry_flush=%d: %llu %c %lu) [%d/%d failures]\n",
+		       entry_flush, l1d_misses_total, entry_flush ? '<' : '>',
+		       entry_flush ? repetitions * l1d_misses_expected :
+		       repetitions * l1d_misses_expected / 2,
+		       repetitions - passes, repetitions);
+		rc = 1;
+	} else {
+		printf("PASS (L1D misses with entry_flush=%d: %llu %c %lu) [%d/%d pass]\n",
+		       entry_flush, l1d_misses_total, entry_flush ? '>' : '<',
+		       entry_flush ? repetitions * l1d_misses_expected :
+		       repetitions * l1d_misses_expected / 2,
+		       passes, repetitions);
+	}
+
+	if (entry_flush == entry_flush_orig) {
+		entry_flush = !entry_flush_orig;
+		if (write_debugfs_file("powerpc/entry_flush", entry_flush) < 0) {
+			perror("error writing to powerpc/entry_flush debugfs file");
+			return 1;
+		}
+		iter = repetitions;
+		l1d_misses_total = 0;
+		passes = 0;
+		goto again;
+	}
+
+	perf_event_disable(fd);
+	close(fd);
+
+	set_dscr(0);
+
+	if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_orig) < 0) {
+		perror("unable to restore original value of powerpc/rfi_flush debugfs file");
+		return 1;
+	}
+
+	if (write_debugfs_file("powerpc/entry_flush", entry_flush_orig) < 0) {
+		perror("unable to restore original value of powerpc/entry_flush debugfs file");
+		return 1;
+	}
+
+	return rc;
+}
+
+int main(int argc, char *argv[])
+{
+	return test_harness(entry_flush_test, "entry_flush_test");
+}
diff --git a/tools/testing/selftests/powerpc/security/flush_utils.c b/tools/testing/selftests/powerpc/security/flush_utils.c
new file mode 100644
index 000000000000..0c3c4c40c7fb
--- /dev/null
+++ b/tools/testing/selftests/powerpc/security/flush_utils.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * Copyright 2018 IBM Corporation.
+ */
+
+#define __SANE_USERSPACE_TYPES__
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "utils.h"
+#include "flush_utils.h"
+
+static inline __u64 load(void *addr)
+{
+	__u64 tmp;
+
+	asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
+
+	return tmp;
+}
+
+void syscall_loop(char *p, unsigned long iterations,
+		  unsigned long zero_size)
+{
+	for (unsigned long i = 0; i < iterations; i++) {
+		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
+			load(p + j);
+		getppid();
+	}
+}
+
+static void sigill_handler(int signr, siginfo_t *info, void *unused)
+{
+	static int warned;
+	ucontext_t *ctx = (ucontext_t *)unused;
+	unsigned long *pc = &UCONTEXT_NIA(ctx);
+
+	/* mtspr 3,RS to check for move to DSCR below */
+	if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {
+		if (!warned++)
+			printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
+		*pc += 4;
+	} else {
+		printf("SIGILL at %p\n", pc);
+		abort();
+	}
+}
+
+void set_dscr(unsigned long val)
+{
+	static int init;
+	struct sigaction sa;
+
+	if (!init) {
+		memset(&sa, 0, sizeof(sa));
+		sa.sa_sigaction = sigill_handler;
+		sa.sa_flags = SA_SIGINFO;
+		if (sigaction(SIGILL, &sa, NULL))
+			perror("sigill_handler");
+		init = 1;
+	}
+
+	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
+}
diff --git a/tools/testing/selftests/powerpc/security/flush_utils.h b/tools/testing/selftests/powerpc/security/flush_utils.h
new file mode 100644
index 000000000000..07a5eb301466
--- /dev/null
+++ b/tools/testing/selftests/powerpc/security/flush_utils.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+/*
+ * Copyright 2018 IBM Corporation.
+ */
+
+#ifndef _SELFTESTS_POWERPC_SECURITY_FLUSH_UTILS_H
+#define _SELFTESTS_POWERPC_SECURITY_FLUSH_UTILS_H
+
+#define CACHELINE_SIZE 128
+
+void syscall_loop(char *p, unsigned long iterations,
+		  unsigned long zero_size);
+
+void set_dscr(unsigned long val);
+
+#endif /* _SELFTESTS_POWERPC_SECURITY_FLUSH_UTILS_H */
diff --git a/tools/testing/selftests/powerpc/security/rfi_flush.c b/tools/testing/selftests/powerpc/security/rfi_flush.c
index 93a65bd1f231..7565fd786640 100644
--- a/tools/testing/selftests/powerpc/security/rfi_flush.c
+++ b/tools/testing/selftests/powerpc/security/rfi_flush.c
@@ -10,71 +10,12 @@
 #include <stdint.h>
 #include <malloc.h>
 #include <unistd.h>
-#include <signal.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include "utils.h"
+#include "flush_utils.h"
 
-#define CACHELINE_SIZE 128
-
-struct perf_event_read {
-	__u64 nr;
-	__u64 l1d_misses;
-};
-
-static inline __u64 load(void *addr)
-{
-	__u64 tmp;
-
-	asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
-
-	return tmp;
-}
-
-static void syscall_loop(char *p, unsigned long iterations,
-			 unsigned long zero_size)
-{
-	for (unsigned long i = 0; i < iterations; i++) {
-		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
-			load(p + j);
-		getppid();
-	}
-}
-
-static void sigill_handler(int signr, siginfo_t *info, void *unused)
-{
-	static int warned = 0;
-	ucontext_t *ctx = (ucontext_t *)unused;
-	unsigned long *pc = &UCONTEXT_NIA(ctx);
-
-	/* mtspr 3,RS to check for move to DSCR below */
-	if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {
-		if (!warned++)
-			printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
-		*pc += 4;
-	} else {
-		printf("SIGILL at %p\n", pc);
-		abort();
-	}
-}
-
-static void set_dscr(unsigned long val)
-{
-	static int init = 0;
-	struct sigaction sa;
-
-	if (!init) {
-		memset(&sa, 0, sizeof(sa));
-		sa.sa_sigaction = sigill_handler;
-		sa.sa_flags = SA_SIGINFO;
-		if (sigaction(SIGILL, &sa, NULL))
-			perror("sigill_handler");
-		init = 1;
-	}
-
-	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
-}
 
 int rfi_flush_test(void)
 {
@@ -85,19 +26,33 @@ int rfi_flush_test(void)
 	__u64 l1d_misses_total = 0;
 	unsigned long iterations = 100000, zero_size = 24 * 1024;
 	unsigned long l1d_misses_expected;
-	int rfi_flush_org, rfi_flush;
+	int rfi_flush_orig, rfi_flush;
+	int have_entry_flush, entry_flush_orig;
 
 	SKIP_IF(geteuid() != 0);
 
 	// The PMU event we use only works on Power7 or later
 	SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06));
 
-	if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_org)) {
+	if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_orig) < 0) {
 		perror("Unable to read powerpc/rfi_flush debugfs file");
 		SKIP_IF(1);
 	}
 
-	rfi_flush = rfi_flush_org;
+	if (read_debugfs_file("powerpc/entry_flush", &entry_flush_orig) < 0) {
+		have_entry_flush = 0;
+	} else {
+		have_entry_flush = 1;
+
+		if (entry_flush_orig != 0) {
+			if (write_debugfs_file("powerpc/entry_flush", 0) < 0) {
+				perror("error writing to powerpc/entry_flush debugfs file");
+				return 1;
+			}
+		}
+	}
+
+	rfi_flush = rfi_flush_orig;
 
 	fd = perf_event_open_counter(PERF_TYPE_RAW, /* L1d miss */ 0x400f0, -1);
 	FAIL_IF(fd < 0);
@@ -106,6 +61,7 @@ int rfi_flush_test(void)
 
 	FAIL_IF(perf_event_enable(fd));
 
+	// disable L1 prefetching
 	set_dscr(1);
 
 	iter = repetitions;
@@ -147,8 +103,8 @@ again:
 		       repetitions * l1d_misses_expected / 2,
 		       passes, repetitions);
 
-	if (rfi_flush == rfi_flush_org) {
-		rfi_flush = !rfi_flush_org;
+	if (rfi_flush == rfi_flush_orig) {
+		rfi_flush = !rfi_flush_orig;
 		if (write_debugfs_file("powerpc/rfi_flush", rfi_flush) < 0) {
 			perror("error writing to powerpc/rfi_flush debugfs file");
 			return 1;
@@ -164,11 +120,19 @@ again:
 
 	set_dscr(0);
 
-	if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_org) < 0) {
+	if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_orig) < 0) {
 		perror("unable to restore original value of powerpc/rfi_flush debugfs file");
 		return 1;
 	}
 
+	if (have_entry_flush) {
+		if (write_debugfs_file("powerpc/entry_flush", entry_flush_orig) < 0) {
+			perror("unable to restore original value of powerpc/entry_flush "
+			       "debugfs file");
+			return 1;
+		}
+	}
+
 	return rc;
 }