These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

23 files changed, 1949 insertions, 53 deletions

diff --git a/kernel/samples/bpf/Makefile b/kernel/samples/bpf/Makefile
index 76e3458a5..edd638b58 100644
--- a/kernel/samples/bpf/Makefile
+++ b/kernel/samples/bpf/Makefile
@@ -4,47 +4,76 @@ obj- := dummy.o
 # List of programs to build
 hostprogs-y := test_verifier test_maps
 hostprogs-y += sock_example
+hostprogs-y += fds_example
 hostprogs-y += sockex1
 hostprogs-y += sockex2
+hostprogs-y += sockex3
 hostprogs-y += tracex1
 hostprogs-y += tracex2
 hostprogs-y += tracex3
 hostprogs-y += tracex4
+hostprogs-y += tracex5
+hostprogs-y += tracex6
+hostprogs-y += trace_output
+hostprogs-y += lathist
 
 test_verifier-objs := test_verifier.o libbpf.o
 test_maps-objs := test_maps.o libbpf.o
 sock_example-objs := sock_example.o libbpf.o
+fds_example-objs := bpf_load.o libbpf.o fds_example.o
 sockex1-objs := bpf_load.o libbpf.o sockex1_user.o
 sockex2-objs := bpf_load.o libbpf.o sockex2_user.o
+sockex3-objs := bpf_load.o libbpf.o sockex3_user.o
 tracex1-objs := bpf_load.o libbpf.o tracex1_user.o
 tracex2-objs := bpf_load.o libbpf.o tracex2_user.o
 tracex3-objs := bpf_load.o libbpf.o tracex3_user.o
 tracex4-objs := bpf_load.o libbpf.o tracex4_user.o
+tracex5-objs := bpf_load.o libbpf.o tracex5_user.o
+tracex6-objs := bpf_load.o libbpf.o tracex6_user.o
+trace_output-objs := bpf_load.o libbpf.o trace_output_user.o
+lathist-objs := bpf_load.o libbpf.o lathist_user.o
 
 # Tell kbuild to always build the programs
 always := $(hostprogs-y)
 always += sockex1_kern.o
 always += sockex2_kern.o
+always += sockex3_kern.o
 always += tracex1_kern.o
 always += tracex2_kern.o
 always += tracex3_kern.o
 always += tracex4_kern.o
+always += tracex5_kern.o
+always += tracex6_kern.o
+always += trace_output_kern.o
 always += tcbpf1_kern.o
+always += lathist_kern.o
 
 HOSTCFLAGS += -I$(objtree)/usr/include
 
 HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable
+HOSTLOADLIBES_fds_example += -lelf
 HOSTLOADLIBES_sockex1 += -lelf
 HOSTLOADLIBES_sockex2 += -lelf
+HOSTLOADLIBES_sockex3 += -lelf
 HOSTLOADLIBES_tracex1 += -lelf
 HOSTLOADLIBES_tracex2 += -lelf
 HOSTLOADLIBES_tracex3 += -lelf
 HOSTLOADLIBES_tracex4 += -lelf -lrt
+HOSTLOADLIBES_tracex5 += -lelf
+HOSTLOADLIBES_tracex6 += -lelf
+HOSTLOADLIBES_trace_output += -lelf -lrt
+HOSTLOADLIBES_lathist += -lelf
 
 # point this to your LLVM backend with bpf support
 LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc
 
-%.o: %.c
+# asm/sysreg.h inline assmbly used by it is incompatible with llvm.
+# But, ehere is not easy way to fix it, so just exclude it since it is
+# useless for BPF samples.
+$(obj)/%.o: $(src)/%.c
 	clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \
-		-D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \
+		-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
 		-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@
+	clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \
+		-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
+		-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=asm -o $@.s
diff --git a/kernel/samples/bpf/bpf_helpers.h b/kernel/samples/bpf/bpf_helpers.h
index f960b5fb3..7ad19e1db 100644
--- a/kernel/samples/bpf/bpf_helpers.h
+++ b/kernel/samples/bpf/bpf_helpers.h
@@ -21,6 +21,24 @@ static unsigned long long (*bpf_ktime_get_ns)(void) =
 	(void *) BPF_FUNC_ktime_get_ns;
 static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
 	(void *) BPF_FUNC_trace_printk;
+static void (*bpf_tail_call)(void *ctx, void *map, int index) =
+	(void *) BPF_FUNC_tail_call;
+static unsigned long long (*bpf_get_smp_processor_id)(void) =
+	(void *) BPF_FUNC_get_smp_processor_id;
+static unsigned long long (*bpf_get_current_pid_tgid)(void) =
+	(void *) BPF_FUNC_get_current_pid_tgid;
+static unsigned long long (*bpf_get_current_uid_gid)(void) =
+	(void *) BPF_FUNC_get_current_uid_gid;
+static int (*bpf_get_current_comm)(void *buf, int buf_size) =
+	(void *) BPF_FUNC_get_current_comm;
+static int (*bpf_perf_event_read)(void *map, int index) =
+	(void *) BPF_FUNC_perf_event_read;
+static int (*bpf_clone_redirect)(void *ctx, int ifindex, int flags) =
+	(void *) BPF_FUNC_clone_redirect;
+static int (*bpf_redirect)(int ifindex, int flags) =
+	(void *) BPF_FUNC_redirect;
+static int (*bpf_perf_event_output)(void *ctx, void *map, int index, void *data, int size) =
+	(void *) BPF_FUNC_perf_event_output;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions
@@ -50,4 +68,41 @@ static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flag
 static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
 	(void *) BPF_FUNC_l4_csum_replace;
 
+#if defined(__x86_64__)
+
+#define PT_REGS_PARM1(x) ((x)->di)
+#define PT_REGS_PARM2(x) ((x)->si)
+#define PT_REGS_PARM3(x) ((x)->dx)
+#define PT_REGS_PARM4(x) ((x)->cx)
+#define PT_REGS_PARM5(x) ((x)->r8)
+#define PT_REGS_RET(x) ((x)->sp)
+#define PT_REGS_FP(x) ((x)->bp)
+#define PT_REGS_RC(x) ((x)->ax)
+#define PT_REGS_SP(x) ((x)->sp)
+
+#elif defined(__s390x__)
+
+#define PT_REGS_PARM1(x) ((x)->gprs[2])
+#define PT_REGS_PARM2(x) ((x)->gprs[3])
+#define PT_REGS_PARM3(x) ((x)->gprs[4])
+#define PT_REGS_PARM4(x) ((x)->gprs[5])
+#define PT_REGS_PARM5(x) ((x)->gprs[6])
+#define PT_REGS_RET(x) ((x)->gprs[14])
+#define PT_REGS_FP(x) ((x)->gprs[11]) /* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_RC(x) ((x)->gprs[2])
+#define PT_REGS_SP(x) ((x)->gprs[15])
+
+#elif defined(__aarch64__)
+
+#define PT_REGS_PARM1(x) ((x)->regs[0])
+#define PT_REGS_PARM2(x) ((x)->regs[1])
+#define PT_REGS_PARM3(x) ((x)->regs[2])
+#define PT_REGS_PARM4(x) ((x)->regs[3])
+#define PT_REGS_PARM5(x) ((x)->regs[4])
+#define PT_REGS_RET(x) ((x)->regs[30])
+#define PT_REGS_FP(x) ((x)->regs[29]) /* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_RC(x) ((x)->regs[0])
+#define PT_REGS_SP(x) ((x)->sp)
+
+#endif
 #endif
diff --git a/kernel/samples/bpf/bpf_load.c b/kernel/samples/bpf/bpf_load.c
index 38dac5a53..da86a8e0a 100644
--- a/kernel/samples/bpf/bpf_load.c
+++ b/kernel/samples/bpf/bpf_load.c
@@ -16,6 +16,7 @@
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <poll.h>
+#include <ctype.h>
 #include "libbpf.h"
 #include "bpf_helpers.h"
 #include "bpf_load.h"
@@ -29,6 +30,19 @@ int map_fd[MAX_MAPS];
 int prog_fd[MAX_PROGS];
 int event_fd[MAX_PROGS];
 int prog_cnt;
+int prog_array_fd = -1;
+
+static int populate_prog_array(const char *event, int prog_fd)
+{
+	int ind = atoi(event), err;
+
+	err = bpf_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
+	if (err < 0) {
+		printf("failed to store prog_fd in prog_array\n");
+		return -1;
+	}
+	return 0;
+}
 
 static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
 {
@@ -54,12 +68,40 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
 		return -1;
 	}
 
+	fd = bpf_prog_load(prog_type, prog, size, license, kern_version);
+	if (fd < 0) {
+		printf("bpf_prog_load() err=%d\n%s", errno, bpf_log_buf);
+		return -1;
+	}
+
+	prog_fd[prog_cnt++] = fd;
+
+	if (is_socket) {
+		event += 6;
+		if (*event != '/')
+			return 0;
+		event++;
+		if (!isdigit(*event)) {
+			printf("invalid prog number\n");
+			return -1;
+		}
+		return populate_prog_array(event, fd);
+	}
+
 	if (is_kprobe || is_kretprobe) {
 		if (is_kprobe)
 			event += 7;
 		else
 			event += 10;
 
+		if (*event == 0) {
+			printf("event name cannot be empty\n");
+			return -1;
+		}
+
+		if (isdigit(*event))
+			return populate_prog_array(event, fd);
+
 		snprintf(buf, sizeof(buf),
 			 "echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events",
 			 is_kprobe ? 'p' : 'r', event, event);
@@ -71,18 +113,6 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
 		}
 	}
 
-	fd = bpf_prog_load(prog_type, prog, size, license, kern_version);
-
-	if (fd < 0) {
-		printf("bpf_prog_load() err=%d\n%s", errno, bpf_log_buf);
-		return -1;
-	}
-
-	prog_fd[prog_cnt++] = fd;
-
-	if (is_socket)
-		return 0;
-
 	strcpy(buf, DEBUGFS);
 	strcat(buf, "events/kprobes/");
 	strcat(buf, event);
@@ -130,6 +160,9 @@ static int load_maps(struct bpf_map_def *maps, int len)
 					   maps[i].max_entries);
 		if (map_fd[i] < 0)
 			return 1;
+
+		if (maps[i].type == BPF_MAP_TYPE_PROG_ARRAY)
+			prog_array_fd = map_fd[i];
 	}
 	return 0;
 }
diff --git a/kernel/samples/bpf/fds_example.c b/kernel/samples/bpf/fds_example.c
new file mode 100644
index 000000000..e2fd16c3d
--- /dev/null
+++ b/kernel/samples/bpf/fds_example.c
@@ -0,0 +1,183 @@
+#include <linux/unistd.h>
+#include <linux/bpf.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "bpf_load.h"
+#include "libbpf.h"
+
+#define BPF_F_PIN	(1 << 0)
+#define BPF_F_GET	(1 << 1)
+#define BPF_F_PIN_GET	(BPF_F_PIN | BPF_F_GET)
+
+#define BPF_F_KEY	(1 << 2)
+#define BPF_F_VAL	(1 << 3)
+#define BPF_F_KEY_VAL	(BPF_F_KEY | BPF_F_VAL)
+
+#define BPF_M_UNSPEC	0
+#define BPF_M_MAP	1
+#define BPF_M_PROG	2
+
+static void usage(void)
+{
+	printf("Usage: fds_example [...]\n");
+	printf("       -F <file>   File to pin/get object\n");
+	printf("       -P          |- pin object\n");
+	printf("       -G          `- get object\n");
+	printf("       -m          eBPF map mode\n");
+	printf("       -k <key>    |- map key\n");
+	printf("       -v <value>  `- map value\n");
+	printf("       -p          eBPF prog mode\n");
+	printf("       -o <object> `- object file\n");
+	printf("       -h          Display this help.\n");
+}
+
+static int bpf_map_create(void)
+{
+	return bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(uint32_t),
+			      sizeof(uint32_t), 1024);
+}
+
+static int bpf_prog_create(const char *object)
+{
+	static const struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN(),
+	};
+
+	if (object) {
+		assert(!load_bpf_file((char *)object));
+		return prog_fd[0];
+	} else {
+		return bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER,
+				     insns, sizeof(insns), "GPL", 0);
+	}
+}
+
+static int bpf_do_map(const char *file, uint32_t flags, uint32_t key,
+		      uint32_t value)
+{
+	int fd, ret;
+
+	if (flags & BPF_F_PIN) {
+		fd = bpf_map_create();
+		printf("bpf: map fd:%d (%s)\n", fd, strerror(errno));
+		assert(fd > 0);
+
+		ret = bpf_obj_pin(fd, file);
+		printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
+		assert(ret == 0);
+	} else {
+		fd = bpf_obj_get(file);
+		printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
+		assert(fd > 0);
+	}
+
+	if ((flags & BPF_F_KEY_VAL) == BPF_F_KEY_VAL) {
+		ret = bpf_update_elem(fd, &key, &value, 0);
+		printf("bpf: fd:%d u->(%u:%u) ret:(%d,%s)\n", fd, key, value,
+		       ret, strerror(errno));
+		assert(ret == 0);
+	} else if (flags & BPF_F_KEY) {
+		ret = bpf_lookup_elem(fd, &key, &value);
+		printf("bpf: fd:%d l->(%u):%u ret:(%d,%s)\n", fd, key, value,
+		       ret, strerror(errno));
+		assert(ret == 0);
+	}
+
+	return 0;
+}
+
+static int bpf_do_prog(const char *file, uint32_t flags, const char *object)
+{
+	int fd, sock, ret;
+
+	if (flags & BPF_F_PIN) {
+		fd = bpf_prog_create(object);
+		printf("bpf: prog fd:%d (%s)\n", fd, strerror(errno));
+		assert(fd > 0);
+
+		ret = bpf_obj_pin(fd, file);
+		printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno));
+		assert(ret == 0);
+	} else {
+		fd = bpf_obj_get(file);
+		printf("bpf: get fd:%d (%s)\n", fd, strerror(errno));
+		assert(fd > 0);
+	}
+
+	sock = open_raw_sock("lo");
+	assert(sock > 0);
+
+	ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &fd, sizeof(fd));
+	printf("bpf: sock:%d <- fd:%d attached ret:(%d,%s)\n", sock, fd,
+	       ret, strerror(errno));
+	assert(ret == 0);
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	const char *file = NULL, *object = NULL;
+	uint32_t key = 0, value = 0, flags = 0;
+	int opt, mode = BPF_M_UNSPEC;
+
+	while ((opt = getopt(argc, argv, "F:PGmk:v:po:")) != -1) {
+		switch (opt) {
+		/* General args */
+		case 'F':
+			file = optarg;
+			break;
+		case 'P':
+			flags |= BPF_F_PIN;
+			break;
+		case 'G':
+			flags |= BPF_F_GET;
+			break;
+		/* Map-related args */
+		case 'm':
+			mode = BPF_M_MAP;
+			break;
+		case 'k':
+			key = strtoul(optarg, NULL, 0);
+			flags |= BPF_F_KEY;
+			break;
+		case 'v':
+			value = strtoul(optarg, NULL, 0);
+			flags |= BPF_F_VAL;
+			break;
+		/* Prog-related args */
+		case 'p':
+			mode = BPF_M_PROG;
+			break;
+		case 'o':
+			object = optarg;
+			break;
+		default:
+			goto out;
+		}
+	}
+
+	if (!(flags & BPF_F_PIN_GET) || !file)
+		goto out;
+
+	switch (mode) {
+	case BPF_M_MAP:
+		return bpf_do_map(file, flags, key, value);
+	case BPF_M_PROG:
+		return bpf_do_prog(file, flags, object);
+	}
+out:
+	usage();
+	return -1;
+}
diff --git a/kernel/samples/bpf/lathist_kern.c b/kernel/samples/bpf/lathist_kern.c
new file mode 100644
index 000000000..18fa08847
--- /dev/null
+++ b/kernel/samples/bpf/lathist_kern.c
@@ -0,0 +1,99 @@
+/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2015 BMW Car IT GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/version.h>
+#include <linux/ptrace.h>
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+#define MAX_ENTRIES	20
+#define MAX_CPU		4
+
+/* We need to stick to static allocated memory (an array instead of
+ * hash table) because managing dynamic memory from the
+ * trace_preempt_[on|off] tracepoints hooks is not supported.
+ */
+
+struct bpf_map_def SEC("maps") my_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(u64),
+	.max_entries = MAX_CPU,
+};
+
+SEC("kprobe/trace_preempt_off")
+int bpf_prog1(struct pt_regs *ctx)
+{
+	int cpu = bpf_get_smp_processor_id();
+	u64 *ts = bpf_map_lookup_elem(&my_map, &cpu);
+
+	if (ts)
+		*ts = bpf_ktime_get_ns();
+
+	return 0;
+}
+
+static unsigned int log2(unsigned int v)
+{
+	unsigned int r;
+	unsigned int shift;
+
+	r = (v > 0xFFFF) << 4; v >>= r;
+	shift = (v > 0xFF) << 3; v >>= shift; r |= shift;
+	shift = (v > 0xF) << 2; v >>= shift; r |= shift;
+	shift = (v > 0x3) << 1; v >>= shift; r |= shift;
+	r |= (v >> 1);
+
+	return r;
+}
+
+static unsigned int log2l(unsigned long v)
+{
+	unsigned int hi = v >> 32;
+
+	if (hi)
+		return log2(hi) + 32;
+	else
+		return log2(v);
+}
+
+struct bpf_map_def SEC("maps") my_lat = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(long),
+	.max_entries = MAX_CPU * MAX_ENTRIES,
+};
+
+SEC("kprobe/trace_preempt_on")
+int bpf_prog2(struct pt_regs *ctx)
+{
+	u64 *ts, cur_ts, delta;
+	int key, cpu;
+	long *val;
+
+	cpu = bpf_get_smp_processor_id();
+	ts = bpf_map_lookup_elem(&my_map, &cpu);
+	if (!ts)
+		return 0;
+
+	cur_ts = bpf_ktime_get_ns();
+	delta = log2l(cur_ts - *ts);
+
+	if (delta > MAX_ENTRIES - 1)
+		delta = MAX_ENTRIES - 1;
+
+	key = cpu * MAX_ENTRIES + delta;
+	val = bpf_map_lookup_elem(&my_lat, &key);
+	if (val)
+		__sync_fetch_and_add((long *)val, 1);
+
+	return 0;
+
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/kernel/samples/bpf/lathist_user.c b/kernel/samples/bpf/lathist_user.c
new file mode 100644
index 000000000..65da8c157
--- /dev/null
+++ b/kernel/samples/bpf/lathist_user.c
@@ -0,0 +1,103 @@
+/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2015 BMW Car IT GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <linux/bpf.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define MAX_ENTRIES	20
+#define MAX_CPU		4
+#define MAX_STARS	40
+
+struct cpu_hist {
+	long data[MAX_ENTRIES];
+	long max;
+};
+
+static struct cpu_hist cpu_hist[MAX_CPU];
+
+static void stars(char *str, long val, long max, int width)
+{
+	int i;
+
+	for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
+		str[i] = '*';
+	if (val > max)
+		str[i - 1] = '+';
+	str[i] = '\0';
+}
+
+static void print_hist(void)
+{
+	char starstr[MAX_STARS];
+	struct cpu_hist *hist;
+	int i, j;
+
+	/* clear screen */
+	printf("\033[2J");
+
+	for (j = 0; j < MAX_CPU; j++) {
+		hist = &cpu_hist[j];
+
+		/* ignore CPUs without data (maybe offline?) */
+		if (hist->max == 0)
+			continue;
+
+		printf("CPU %d\n", j);
+		printf("      latency        : count     distribution\n");
+		for (i = 1; i <= MAX_ENTRIES; i++) {
+			stars(starstr, hist->data[i - 1], hist->max, MAX_STARS);
+			printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
+				(1l << i) >> 1, (1l << i) - 1,
+				hist->data[i - 1], MAX_STARS, starstr);
+		}
+	}
+}
+
+static void get_data(int fd)
+{
+	long key, value;
+	int c, i;
+
+	for (i = 0; i < MAX_CPU; i++)
+		cpu_hist[i].max = 0;
+
+	for (c = 0; c < MAX_CPU; c++) {
+		for (i = 0; i < MAX_ENTRIES; i++) {
+			key = c * MAX_ENTRIES + i;
+			bpf_lookup_elem(fd, &key, &value);
+
+			cpu_hist[c].data[i] = value;
+			if (value > cpu_hist[c].max)
+				cpu_hist[c].max = value;
+		}
+	}
+}
+
+int main(int argc, char **argv)
+{
+	char filename[256];
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	while (1) {
+		get_data(map_fd[1]);
+		print_hist();
+		sleep(5);
+	}
+
+	return 0;
+}
diff --git a/kernel/samples/bpf/libbpf.c b/kernel/samples/bpf/libbpf.c
index 7e1efa7e2..65a8d48d2 100644
--- a/kernel/samples/bpf/libbpf.c
+++ b/kernel/samples/bpf/libbpf.c
@@ -103,6 +103,25 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 	return syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 }
 
+int bpf_obj_pin(int fd, const char *pathname)
+{
+	union bpf_attr attr = {
+		.pathname	= ptr_to_u64((void *)pathname),
+		.bpf_fd		= fd,
+	};
+
+	return syscall(__NR_bpf, BPF_OBJ_PIN, &attr, sizeof(attr));
+}
+
+int bpf_obj_get(const char *pathname)
+{
+	union bpf_attr attr = {
+		.pathname	= ptr_to_u64((void *)pathname),
+	};
+
+	return syscall(__NR_bpf, BPF_OBJ_GET, &attr, sizeof(attr));
+}
+
 int open_raw_sock(const char *name)
 {
 	struct sockaddr_ll sll;
diff --git a/kernel/samples/bpf/libbpf.h b/kernel/samples/bpf/libbpf.h
index 7235e292a..014aacf91 100644
--- a/kernel/samples/bpf/libbpf.h
+++ b/kernel/samples/bpf/libbpf.h
@@ -15,6 +15,9 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 		  const struct bpf_insn *insns, int insn_len,
 		  const char *license, int kern_version);
 
+int bpf_obj_pin(int fd, const char *pathname);
+int bpf_obj_get(const char *pathname);
+
 #define LOG_BUF_SIZE 65536
 extern char bpf_log_buf[LOG_BUF_SIZE];
 
@@ -64,6 +67,14 @@ extern char bpf_log_buf[LOG_BUF_SIZE];
 		.off   = 0,					\
 		.imm   = 0 })
 
+#define BPF_MOV32_REG(DST, SRC)					\
+	((struct bpf_insn) {					\
+		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
+		.dst_reg = DST,					\
+		.src_reg = SRC,					\
+		.off   = 0,					\
+		.imm   = 0 })
+
 /* Short form of mov, dst_reg = imm32 */
 
 #define BPF_MOV64_IMM(DST, IMM)					\
diff --git a/kernel/samples/bpf/sockex3_kern.c b/kernel/samples/bpf/sockex3_kern.c
new file mode 100644
index 000000000..41ae2fd21
--- /dev/null
+++ b/kernel/samples/bpf/sockex3_kern.c
@@ -0,0 +1,290 @@
+/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+#include <uapi/linux/in.h>
+#include <uapi/linux/if.h>
+#include <uapi/linux/if_ether.h>
+#include <uapi/linux/ip.h>
+#include <uapi/linux/ipv6.h>
+#include <uapi/linux/if_tunnel.h>
+#include <uapi/linux/mpls.h>
+#define IP_MF		0x2000
+#define IP_OFFSET	0x1FFF
+
+#define PROG(F) SEC("socket/"__stringify(F)) int bpf_func_##F
+
+struct bpf_map_def SEC("maps") jmp_table = {
+	.type = BPF_MAP_TYPE_PROG_ARRAY,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(u32),
+	.max_entries = 8,
+};
+
+#define PARSE_VLAN 1
+#define PARSE_MPLS 2
+#define PARSE_IP 3
+#define PARSE_IPV6 4
+
+/* protocol dispatch routine.
+ * It tail-calls next BPF program depending on eth proto
+ * Note, we could have used:
+ * bpf_tail_call(skb, &jmp_table, proto);
+ * but it would need large prog_array
+ */
+static inline void parse_eth_proto(struct __sk_buff *skb, u32 proto)
+{
+	switch (proto) {
+	case ETH_P_8021Q:
+	case ETH_P_8021AD:
+		bpf_tail_call(skb, &jmp_table, PARSE_VLAN);
+		break;
+	case ETH_P_MPLS_UC:
+	case ETH_P_MPLS_MC:
+		bpf_tail_call(skb, &jmp_table, PARSE_MPLS);
+		break;
+	case ETH_P_IP:
+		bpf_tail_call(skb, &jmp_table, PARSE_IP);
+		break;
+	case ETH_P_IPV6:
+		bpf_tail_call(skb, &jmp_table, PARSE_IPV6);
+		break;
+	}
+}
+
+struct vlan_hdr {
+	__be16 h_vlan_TCI;
+	__be16 h_vlan_encapsulated_proto;
+};
+
+struct flow_keys {
+	__be32 src;
+	__be32 dst;
+	union {
+		__be32 ports;
+		__be16 port16[2];
+	};
+	__u32 ip_proto;
+};
+
+static inline int ip_is_fragment(struct __sk_buff *ctx, __u64 nhoff)
+{
+	return load_half(ctx, nhoff + offsetof(struct iphdr, frag_off))
+		& (IP_MF | IP_OFFSET);
+}
+
+static inline __u32 ipv6_addr_hash(struct __sk_buff *ctx, __u64 off)
+{
+	__u64 w0 = load_word(ctx, off);
+	__u64 w1 = load_word(ctx, off + 4);
+	__u64 w2 = load_word(ctx, off + 8);
+	__u64 w3 = load_word(ctx, off + 12);
+
+	return (__u32)(w0 ^ w1 ^ w2 ^ w3);
+}
+
+struct globals {
+	struct flow_keys flow;
+};
+
+struct bpf_map_def SEC("maps") percpu_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(struct globals),
+	.max_entries = 32,
+};
+
+/* user poor man's per_cpu until native support is ready */
+static struct globals *this_cpu_globals(void)
+{
+	u32 key = bpf_get_smp_processor_id();
+
+	return bpf_map_lookup_elem(&percpu_map, &key);
+}
+
+/* some simple stats for user space consumption */
+struct pair {
+	__u64 packets;
+	__u64 bytes;
+};
+
+struct bpf_map_def SEC("maps") hash_map = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(struct flow_keys),
+	.value_size = sizeof(struct pair),
+	.max_entries = 1024,
+};
+
+static void update_stats(struct __sk_buff *skb, struct globals *g)
+{
+	struct flow_keys key = g->flow;
+	struct pair *value;
+
+	value = bpf_map_lookup_elem(&hash_map, &key);
+	if (value) {
+		__sync_fetch_and_add(&value->packets, 1);
+		__sync_fetch_and_add(&value->bytes, skb->len);
+	} else {
+		struct pair val = {1, skb->len};
+
+		bpf_map_update_elem(&hash_map, &key, &val, BPF_ANY);
+	}
+}
+
+static __always_inline void parse_ip_proto(struct __sk_buff *skb,
+					   struct globals *g, __u32 ip_proto)
+{
+	__u32 nhoff = skb->cb[0];
+	int poff;
+
+	switch (ip_proto) {
+	case IPPROTO_GRE: {
+		struct gre_hdr {
+			__be16 flags;
+			__be16 proto;
+		};
+
+		__u32 gre_flags = load_half(skb,
+					    nhoff + offsetof(struct gre_hdr, flags));
+		__u32 gre_proto = load_half(skb,
+					    nhoff + offsetof(struct gre_hdr, proto));
+
+		if (gre_flags & (GRE_VERSION|GRE_ROUTING))
+			break;
+
+		nhoff += 4;
+		if (gre_flags & GRE_CSUM)
+			nhoff += 4;
+		if (gre_flags & GRE_KEY)
+			nhoff += 4;
+		if (gre_flags & GRE_SEQ)
+			nhoff += 4;
+
+		skb->cb[0] = nhoff;
+		parse_eth_proto(skb, gre_proto);
+		break;
+	}
+	case IPPROTO_IPIP:
+		parse_eth_proto(skb, ETH_P_IP);
+		break;
+	case IPPROTO_IPV6:
+		parse_eth_proto(skb, ETH_P_IPV6);
+		break;
+	case IPPROTO_TCP:
+	case IPPROTO_UDP:
+		g->flow.ports = load_word(skb, nhoff);
+	case IPPROTO_ICMP:
+		g->flow.ip_proto = ip_proto;
+		update_stats(skb, g);
+		break;
+	default:
+		break;
+	}
+}
+
+PROG(PARSE_IP)(struct __sk_buff *skb)
+{
+	struct globals *g = this_cpu_globals();
+	__u32 nhoff, verlen, ip_proto;
+
+	if (!g)
+		return 0;
+
+	nhoff = skb->cb[0];
+
+	if (unlikely(ip_is_fragment(skb, nhoff)))
+		return 0;
+
+	ip_proto = load_byte(skb, nhoff + offsetof(struct iphdr, protocol));
+
+	if (ip_proto != IPPROTO_GRE) {
+		g->flow.src = load_word(skb, nhoff + offsetof(struct iphdr, saddr));
+		g->flow.dst = load_word(skb, nhoff + offsetof(struct iphdr, daddr));
+	}
+
+	verlen = load_byte(skb, nhoff + 0/*offsetof(struct iphdr, ihl)*/);
+	nhoff += (verlen & 0xF) << 2;
+
+	skb->cb[0] = nhoff;
+	parse_ip_proto(skb, g, ip_proto);
+	return 0;
+}
+
+PROG(PARSE_IPV6)(struct __sk_buff *skb)
+{
+	struct globals *g = this_cpu_globals();
+	__u32 nhoff, ip_proto;
+
+	if (!g)
+		return 0;
+
+	nhoff = skb->cb[0];
+
+	ip_proto = load_byte(skb,
+			     nhoff + offsetof(struct ipv6hdr, nexthdr));
+	g->flow.src = ipv6_addr_hash(skb,
+				     nhoff + offsetof(struct ipv6hdr, saddr));
+	g->flow.dst = ipv6_addr_hash(skb,
+				     nhoff + offsetof(struct ipv6hdr, daddr));
+	nhoff += sizeof(struct ipv6hdr);
+
+	skb->cb[0] = nhoff;
+	parse_ip_proto(skb, g, ip_proto);
+	return 0;
+}
+
+PROG(PARSE_VLAN)(struct __sk_buff *skb)
+{
+	__u32 nhoff, proto;
+
+	nhoff = skb->cb[0];
+
+	proto = load_half(skb, nhoff + offsetof(struct vlan_hdr,
+						h_vlan_encapsulated_proto));
+	nhoff += sizeof(struct vlan_hdr);
+	skb->cb[0] = nhoff;
+
+	parse_eth_proto(skb, proto);
+
+	return 0;
+}
+
+PROG(PARSE_MPLS)(struct __sk_buff *skb)
+{
+	__u32 nhoff, label;
+
+	nhoff = skb->cb[0];
+
+	label = load_word(skb, nhoff);
+	nhoff += sizeof(struct mpls_label);
+	skb->cb[0] = nhoff;
+
+	if (label & MPLS_LS_S_MASK) {
+		__u8 verlen = load_byte(skb, nhoff);
+		if ((verlen & 0xF0) == 4)
+			parse_eth_proto(skb, ETH_P_IP);
+		else
+			parse_eth_proto(skb, ETH_P_IPV6);
+	} else {
+		parse_eth_proto(skb, ETH_P_MPLS_UC);
+	}
+
+	return 0;
+}
+
+SEC("socket/0")
+int main_prog(struct __sk_buff *skb)
+{
+	__u32 nhoff = ETH_HLEN;
+	__u32 proto = load_half(skb, 12);
+
+	skb->cb[0] = nhoff;
+	parse_eth_proto(skb, proto);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/kernel/samples/bpf/sockex3_user.c b/kernel/samples/bpf/sockex3_user.c
new file mode 100644
index 000000000..2617772d0
--- /dev/null
+++ b/kernel/samples/bpf/sockex3_user.c
@@ -0,0 +1,66 @@
+#include <stdio.h>
+#include <assert.h>
+#include <linux/bpf.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+#include <unistd.h>
+#include <arpa/inet.h>
+
+struct flow_keys {
+	__be32 src;
+	__be32 dst;
+	union {
+		__be32 ports;
+		__be16 port16[2];
+	};
+	__u32 ip_proto;
+};
+
+struct pair {
+	__u64 packets;
+	__u64 bytes;
+};
+
+int main(int argc, char **argv)
+{
+	char filename[256];
+	FILE *f;
+	int i, sock;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	sock = open_raw_sock("lo");
+
+	assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd[4],
+			  sizeof(__u32)) == 0);
+
+	if (argc > 1)
+		f = popen("ping -c5 localhost", "r");
+	else
+		f = popen("netperf -l 4 localhost", "r");
+	(void) f;
+
+	for (i = 0; i < 5; i++) {
+		struct flow_keys key = {}, next_key;
+		struct pair value;
+
+		sleep(1);
+		printf("IP     src.port -> dst.port               bytes      packets\n");
+		while (bpf_get_next_key(map_fd[2], &key, &next_key) == 0) {
+			bpf_lookup_elem(map_fd[2], &next_key, &value);
+			printf("%s.%05d -> %s.%05d %12lld %12lld\n",
+			       inet_ntoa((struct in_addr){htonl(next_key.src)}),
+			       next_key.port16[0],
+			       inet_ntoa((struct in_addr){htonl(next_key.dst)}),
+			       next_key.port16[1],
+			       value.bytes, value.packets);
+			key = next_key;
+		}
+	}
+	return 0;
+}
diff --git a/kernel/samples/bpf/tcbpf1_kern.c b/kernel/samples/bpf/tcbpf1_kern.c
index 7c27710f8..fa051b3d5 100644
--- a/kernel/samples/bpf/tcbpf1_kern.c
+++ b/kernel/samples/bpf/tcbpf1_kern.c
@@ -5,7 +5,7 @@
 #include <uapi/linux/in.h>
 #include <uapi/linux/tcp.h>
 #include <uapi/linux/filter.h>
-
+#include <uapi/linux/pkt_cls.h>
 #include "bpf_helpers.h"
 
 /* compiler workaround */
@@ -21,7 +21,7 @@ static inline void set_dst_mac(struct __sk_buff *skb, char *mac)
 
 static inline void set_ip_tos(struct __sk_buff *skb, __u8 new_tos)
 {
-	__u8 old_tos = load_byte(skb, BPF_LL_OFF + TOS_OFF);
+	__u8 old_tos = load_byte(skb, TOS_OFF);
 
 	bpf_l3_csum_replace(skb, IP_CSUM_OFF, htons(old_tos), htons(new_tos), 2);
 	bpf_skb_store_bytes(skb, TOS_OFF, &new_tos, sizeof(new_tos), 0);
@@ -34,7 +34,7 @@ static inline void set_ip_tos(struct __sk_buff *skb, __u8 new_tos)
 
 static inline void set_tcp_ip_src(struct __sk_buff *skb, __u32 new_ip)
 {
-	__u32 old_ip = _htonl(load_word(skb, BPF_LL_OFF + IP_SRC_OFF));
+	__u32 old_ip = _htonl(load_word(skb, IP_SRC_OFF));
 
 	bpf_l4_csum_replace(skb, TCP_CSUM_OFF, old_ip, new_ip, IS_PSEUDO | sizeof(new_ip));
 	bpf_l3_csum_replace(skb, IP_CSUM_OFF, old_ip, new_ip, sizeof(new_ip));
@@ -44,7 +44,7 @@ static inline void set_tcp_ip_src(struct __sk_buff *skb, __u32 new_ip)
 #define TCP_DPORT_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, dest))
 static inline void set_tcp_dest_port(struct __sk_buff *skb, __u16 new_port)
 {
-	__u16 old_port = htons(load_half(skb, BPF_LL_OFF + TCP_DPORT_OFF));
+	__u16 old_port = htons(load_half(skb, TCP_DPORT_OFF));
 
 	bpf_l4_csum_replace(skb, TCP_CSUM_OFF, old_port, new_port, sizeof(new_port));
 	bpf_skb_store_bytes(skb, TCP_DPORT_OFF, &new_port, sizeof(new_port), 0);
@@ -53,7 +53,7 @@ static inline void set_tcp_dest_port(struct __sk_buff *skb, __u16 new_port)
 SEC("classifier")
 int bpf_prog1(struct __sk_buff *skb)
 {
-	__u8 proto = load_byte(skb, BPF_LL_OFF + ETH_HLEN + offsetof(struct iphdr, protocol));
+	__u8 proto = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol));
 	long *value;
 
 	if (proto == IPPROTO_TCP) {
@@ -64,4 +64,26 @@ int bpf_prog1(struct __sk_buff *skb)
 
 	return 0;
 }
+SEC("redirect_xmit")
+int _redirect_xmit(struct __sk_buff *skb)
+{
+	return bpf_redirect(skb->ifindex + 1, 0);
+}
+SEC("redirect_recv")
+int _redirect_recv(struct __sk_buff *skb)
+{
+	return bpf_redirect(skb->ifindex + 1, 1);
+}
+SEC("clone_redirect_xmit")
+int _clone_redirect_xmit(struct __sk_buff *skb)
+{
+	bpf_clone_redirect(skb, skb->ifindex + 1, 0);
+	return TC_ACT_SHOT;
+}
+SEC("clone_redirect_recv")
+int _clone_redirect_recv(struct __sk_buff *skb)
+{
+	bpf_clone_redirect(skb, skb->ifindex + 1, 1);
+	return TC_ACT_SHOT;
+}
 char _license[] SEC("license") = "GPL";
diff --git a/kernel/samples/bpf/test_verifier.c b/kernel/samples/bpf/test_verifier.c
index 12f3780af..563c507c0 100644
--- a/kernel/samples/bpf/test_verifier.c
+++ b/kernel/samples/bpf/test_verifier.c
@@ -15,20 +15,28 @@
 #include <string.h>
 #include <linux/filter.h>
 #include <stddef.h>
+#include <stdbool.h>
+#include <sys/resource.h>
 #include "libbpf.h"
 
 #define MAX_INSNS 512
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
 
+#define MAX_FIXUPS 8
+
 struct bpf_test {
 	const char *descr;
 	struct bpf_insn	insns[MAX_INSNS];
-	int fixup[32];
+	int fixup[MAX_FIXUPS];
+	int prog_array_fixup[MAX_FIXUPS];
 	const char *errstr;
+	const char *errstr_unpriv;
 	enum {
+		UNDEF,
 		ACCEPT,
 		REJECT
-	} result;
+	} result, result_unpriv;
+	enum bpf_prog_type prog_type;
 };
 
 static struct bpf_test tests[] = {
@@ -95,6 +103,7 @@ static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.errstr = "invalid BPF_LD_IMM insn",
+		.errstr_unpriv = "R1 pointer comparison",
 		.result = REJECT,
 	},
 	{
@@ -108,6 +117,7 @@ static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.errstr = "invalid BPF_LD_IMM insn",
+		.errstr_unpriv = "R1 pointer comparison",
 		.result = REJECT,
 	},
 	{
@@ -218,6 +228,7 @@ static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.errstr = "R0 !read_ok",
+		.errstr_unpriv = "R1 pointer comparison",
 		.result = REJECT,
 	},
 	{
@@ -293,7 +304,9 @@ static struct bpf_test tests[] = {
 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R0 leaks addr",
 		.result = ACCEPT,
+		.result_unpriv = REJECT,
 	},
 	{
 		"check corrupted spill/fill",
@@ -309,6 +322,7 @@ static struct bpf_test tests[] = {
 
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "attempt to corrupt spilled",
 		.errstr = "corrupted spill",
 		.result = REJECT,
 	},
@@ -472,6 +486,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup = {3},
 		.errstr = "R0 invalid mem access",
+		.errstr_unpriv = "R0 leaks addr",
 		.result = REJECT,
 	},
 	{
@@ -494,6 +509,8 @@ static struct bpf_test tests[] = {
 			BPF_MOV64_IMM(BPF_REG_0, 0),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -520,6 +537,8 @@ static struct bpf_test tests[] = {
 			BPF_MOV64_IMM(BPF_REG_0, 0),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -554,6 +573,8 @@ static struct bpf_test tests[] = {
 			BPF_EXIT_INSN(),
 		},
 		.fixup = {24},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -602,6 +623,8 @@ static struct bpf_test tests[] = {
 			BPF_MOV64_IMM(BPF_REG_0, 0),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -641,6 +664,8 @@ static struct bpf_test tests[] = {
 			BPF_MOV64_IMM(BPF_REG_0, 0),
 			BPF_EXIT_INSN(),
 		},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
 		.result = ACCEPT,
 	},
 	{
@@ -698,6 +723,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup = {4},
 		.errstr = "different pointers",
+		.errstr_unpriv = "R1 pointer comparison",
 		.result = REJECT,
 	},
 	{
@@ -719,6 +745,7 @@ static struct bpf_test tests[] = {
 		},
 		.fixup = {6},
 		.errstr = "different pointers",
+		.errstr_unpriv = "R1 pointer comparison",
 		.result = REJECT,
 	},
 	{
@@ -741,7 +768,417 @@ static struct bpf_test tests[] = {
 		},
 		.fixup = {7},
 		.errstr = "different pointers",
+		.errstr_unpriv = "R1 pointer comparison",
+		.result = REJECT,
+	},
+	{
+		"check skb->mark is not writeable by sockets",
+		.insns = {
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_1,
+				    offsetof(struct __sk_buff, mark)),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "invalid bpf_context access",
+		.errstr_unpriv = "R1 leaks addr",
+		.result = REJECT,
+	},
+	{
+		"check skb->tc_index is not writeable by sockets",
+		.insns = {
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_1,
+				    offsetof(struct __sk_buff, tc_index)),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "invalid bpf_context access",
+		.errstr_unpriv = "R1 leaks addr",
+		.result = REJECT,
+	},
+	{
+		"check non-u32 access to cb",
+		.insns = {
+			BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[0])),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "invalid bpf_context access",
+		.errstr_unpriv = "R1 leaks addr",
+		.result = REJECT,
+	},
+	{
+		"check out of range skb->cb access",
+		.insns = {
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[0]) + 256),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "invalid bpf_context access",
+		.errstr_unpriv = "",
+		.result = REJECT,
+		.prog_type = BPF_PROG_TYPE_SCHED_ACT,
+	},
+	{
+		"write skb fields from socket prog",
+		.insns = {
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[4])),
+			BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1),
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, mark)),
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, tc_index)),
+			BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1),
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[0])),
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[2])),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.errstr_unpriv = "R1 leaks addr",
+		.result_unpriv = REJECT,
+	},
+	{
+		"write skb fields from tc_cls_act prog",
+		.insns = {
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, cb[0])),
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+				    offsetof(struct __sk_buff, mark)),
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+				    offsetof(struct __sk_buff, tc_index)),
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+				    offsetof(struct __sk_buff, tc_index)),
+			BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+				    offsetof(struct __sk_buff, cb[3])),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+	},
+	{
+		"PTR_TO_STACK store/load",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -10),
+			BPF_ST_MEM(BPF_DW, BPF_REG_1, 2, 0xfaceb00c),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 2),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+	},
+	{
+		"PTR_TO_STACK store/load - bad alignment on off",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_1, 2, 0xfaceb00c),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 2),
+			BPF_EXIT_INSN(),
+		},
+		.result = REJECT,
+		.errstr = "misaligned access off -6 size 8",
+	},
+	{
+		"PTR_TO_STACK store/load - bad alignment on reg",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -10),
+			BPF_ST_MEM(BPF_DW, BPF_REG_1, 8, 0xfaceb00c),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 8),
+			BPF_EXIT_INSN(),
+		},
+		.result = REJECT,
+		.errstr = "misaligned access off -2 size 8",
+	},
+	{
+		"PTR_TO_STACK store/load - out of bounds low",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -80000),
+			BPF_ST_MEM(BPF_DW, BPF_REG_1, 8, 0xfaceb00c),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 8),
+			BPF_EXIT_INSN(),
+		},
 		.result = REJECT,
+		.errstr = "invalid stack off=-79992 size=8",
+	},
+	{
+		"PTR_TO_STACK store/load - out of bounds high",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_1, 8, 0xfaceb00c),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 8),
+			BPF_EXIT_INSN(),
+		},
+		.result = REJECT,
+		.errstr = "invalid stack off=0 size=8",
+	},
+	{
+		"unpriv: return pointer",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R0 leaks addr",
+	},
+	{
+		"unpriv: add const to pointer",
+		.insns = {
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R1 pointer arithmetic",
+	},
+	{
+		"unpriv: add pointer to pointer",
+		.insns = {
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_10),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R1 pointer arithmetic",
+	},
+	{
+		"unpriv: neg pointer",
+		.insns = {
+			BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R1 pointer arithmetic",
+	},
+	{
+		"unpriv: cmp pointer with const",
+		.insns = {
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R1 pointer comparison",
+	},
+	{
+		"unpriv: cmp pointer with pointer",
+		.insns = {
+			BPF_JMP_REG(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.result = ACCEPT,
+		.result_unpriv = REJECT,
+		.errstr_unpriv = "R10 pointer comparison",
+	},
+	{
+		"unpriv: check that printk is disallowed",
+		.insns = {
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+			BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+			BPF_MOV64_IMM(BPF_REG_2, 8),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_trace_printk),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "unknown func 6",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: pass pointer to helper function",
+		.insns = {
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_update_elem),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup = {3},
+		.errstr_unpriv = "R4 leaks addr",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: indirectly pass pointer on stack to helper function",
+		.insns = {
+			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup = {3},
+		.errstr = "invalid indirect read from stack off -8+0 size 8",
+		.result = REJECT,
+	},
+	{
+		"unpriv: mangle pointer on stack 1",
+		.insns = {
+			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+			BPF_ST_MEM(BPF_W, BPF_REG_10, -8, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "attempt to corrupt spilled",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: mangle pointer on stack 2",
+		.insns = {
+			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+			BPF_ST_MEM(BPF_B, BPF_REG_10, -1, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "attempt to corrupt spilled",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: read pointer from stack in small chunks",
+		.insns = {
+			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -8),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "invalid size",
+		.result = REJECT,
+	},
+	{
+		"unpriv: write pointer into ctx",
+		.insns = {
+			BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R1 leaks addr",
+		.result_unpriv = REJECT,
+		.errstr = "invalid bpf_context access",
+		.result = REJECT,
+	},
+	{
+		"unpriv: write pointer into map elem value",
+		.insns = {
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+			BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup = {3},
+		.errstr_unpriv = "R0 leaks addr",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: partial copy of pointer",
+		.insns = {
+			BPF_MOV32_REG(BPF_REG_1, BPF_REG_10),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R10 partial copy",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: pass pointer to tail_call",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+			BPF_LD_MAP_FD(BPF_REG_2, 0),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.prog_array_fixup = {1},
+		.errstr_unpriv = "R3 leaks addr into helper",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: cmp map pointer with zero",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_1, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup = {1},
+		.errstr_unpriv = "R1 pointer comparison",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: write into frame pointer",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_10, BPF_REG_1),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr = "frame pointer is read only",
+		.result = REJECT,
+	},
+	{
+		"unpriv: cmp of frame pointer",
+		.insns = {
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_10, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R10 pointer comparison",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: cmp of stack pointer",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R2 pointer comparison",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
+	},
+	{
+		"unpriv: obfuscate stack pointer",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R2 pointer arithmetic",
+		.result_unpriv = REJECT,
+		.result = ACCEPT,
 	},
 };
 
@@ -758,13 +1195,24 @@ static int probe_filter_length(struct bpf_insn *fp)
 
 static int create_map(void)
 {
-	long long key, value = 0;
 	int map_fd;
 
-	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
-	if (map_fd < 0) {
+	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH,
+				sizeof(long long), sizeof(long long), 1024);
+	if (map_fd < 0)
 		printf("failed to create map '%s'\n", strerror(errno));
-	}
+
+	return map_fd;
+}
+
+static int create_prog_array(void)
+{
+	int map_fd;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY,
+				sizeof(int), sizeof(int), 4);
+	if (map_fd < 0)
+		printf("failed to create prog_array '%s'\n", strerror(errno));
 
 	return map_fd;
 }
@@ -772,12 +1220,17 @@ static int create_map(void)
 static int test(void)
 {
 	int prog_fd, i, pass_cnt = 0, err_cnt = 0;
+	bool unpriv = geteuid() != 0;
 
 	for (i = 0; i < ARRAY_SIZE(tests); i++) {
 		struct bpf_insn *prog = tests[i].insns;
+		int prog_type = tests[i].prog_type;
 		int prog_len = probe_filter_length(prog);
 		int *fixup = tests[i].fixup;
-		int map_fd = -1;
+		int *prog_array_fixup = tests[i].prog_array_fixup;
+		int expected_result;
+		const char *expected_errstr;
+		int map_fd = -1, prog_array_fd = -1;
 
 		if (*fixup) {
 			map_fd = create_map();
@@ -787,13 +1240,31 @@ static int test(void)
 				fixup++;
 			} while (*fixup);
 		}
+		if (*prog_array_fixup) {
+			prog_array_fd = create_prog_array();
+
+			do {
+				prog[*prog_array_fixup].imm = prog_array_fd;
+				prog_array_fixup++;
+			} while (*prog_array_fixup);
+		}
 		printf("#%d %s ", i, tests[i].descr);
 
-		prog_fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, prog,
-					prog_len * sizeof(struct bpf_insn),
+		prog_fd = bpf_prog_load(prog_type ?: BPF_PROG_TYPE_SOCKET_FILTER,
+					prog, prog_len * sizeof(struct bpf_insn),
 					"GPL", 0);
 
-		if (tests[i].result == ACCEPT) {
+		if (unpriv && tests[i].result_unpriv != UNDEF)
+			expected_result = tests[i].result_unpriv;
+		else
+			expected_result = tests[i].result;
+
+		if (unpriv && tests[i].errstr_unpriv)
+			expected_errstr = tests[i].errstr_unpriv;
+		else
+			expected_errstr = tests[i].errstr;
+
+		if (expected_result == ACCEPT) {
 			if (prog_fd < 0) {
 				printf("FAIL\nfailed to load prog '%s'\n",
 				       strerror(errno));
@@ -808,7 +1279,7 @@ static int test(void)
 				err_cnt++;
 				goto fail;
 			}
-			if (strstr(bpf_log_buf, tests[i].errstr) == 0) {
+			if (strstr(bpf_log_buf, expected_errstr) == 0) {
 				printf("FAIL\nunexpected error message: %s",
 				       bpf_log_buf);
 				err_cnt++;
@@ -821,6 +1292,8 @@ static int test(void)
 fail:
 		if (map_fd >= 0)
 			close(map_fd);
+		if (prog_array_fd >= 0)
+			close(prog_array_fd);
 		close(prog_fd);
 
 	}
@@ -831,5 +1304,8 @@ fail:
 
 int main(void)
 {
+	struct rlimit r = {1 << 20, 1 << 20};
+
+	setrlimit(RLIMIT_MEMLOCK, &r);
 	return test();
 }
diff --git a/kernel/samples/bpf/trace_output_kern.c b/kernel/samples/bpf/trace_output_kern.c
new file mode 100644
index 000000000..8d8d1ec42
--- /dev/null
+++ b/kernel/samples/bpf/trace_output_kern.c
@@ -0,0 +1,31 @@
+#include <linux/ptrace.h>
+#include <linux/version.h>
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") my_map = {
+	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(u32),
+	.max_entries = 2,
+};
+
+SEC("kprobe/sys_write")
+int bpf_prog1(struct pt_regs *ctx)
+{
+	struct S {
+		u64 pid;
+		u64 cookie;
+	} data;
+
+	memset(&data, 0, sizeof(data));
+	data.pid = bpf_get_current_pid_tgid();
+	data.cookie = 0x12345678;
+
+	bpf_perf_event_output(ctx, &my_map, 0, &data, sizeof(data));
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/kernel/samples/bpf/trace_output_user.c b/kernel/samples/bpf/trace_output_user.c
new file mode 100644
index 000000000..661a7d052
--- /dev/null
+++ b/kernel/samples/bpf/trace_output_user.c
@@ -0,0 +1,196 @@
+/* This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+#include <linux/perf_event.h>
+#include <linux/bpf.h>
+#include <errno.h>
+#include <assert.h>
+#include <sys/syscall.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <time.h>
+#include <signal.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+static int pmu_fd;
+
+int page_size;
+int page_cnt = 8;
+volatile struct perf_event_mmap_page *header;
+
+typedef void (*print_fn)(void *data, int size);
+
+static int perf_event_mmap(int fd)
+{
+	void *base;
+	int mmap_size;
+
+	page_size = getpagesize();
+	mmap_size = page_size * (page_cnt + 1);
+
+	base = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	if (base == MAP_FAILED) {
+		printf("mmap err\n");
+		return -1;
+	}
+
+	header = base;
+	return 0;
+}
+
+static int perf_event_poll(int fd)
+{
+	struct pollfd pfd = { .fd = fd, .events = POLLIN };
+
+	return poll(&pfd, 1, 1000);
+}
+
+struct perf_event_sample {
+	struct perf_event_header header;
+	__u32 size;
+	char data[];
+};
+
+void perf_event_read(print_fn fn)
+{
+	__u64 data_tail = header->data_tail;
+	__u64 data_head = header->data_head;
+	__u64 buffer_size = page_cnt * page_size;
+	void *base, *begin, *end;
+	char buf[256];
+
+	asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */
+	if (data_head == data_tail)
+		return;
+
+	base = ((char *)header) + page_size;
+
+	begin = base + data_tail % buffer_size;
+	end = base + data_head % buffer_size;
+
+	while (begin != end) {
+		struct perf_event_sample *e;
+
+		e = begin;
+		if (begin + e->header.size > base + buffer_size) {
+			long len = base + buffer_size - begin;
+
+			assert(len < e->header.size);
+			memcpy(buf, begin, len);
+			memcpy(buf + len, base, e->header.size - len);
+			e = (void *) buf;
+			begin = base + e->header.size - len;
+		} else if (begin + e->header.size == base + buffer_size) {
+			begin = base;
+		} else {
+			begin += e->header.size;
+		}
+
+		if (e->header.type == PERF_RECORD_SAMPLE) {
+			fn(e->data, e->size);
+		} else if (e->header.type == PERF_RECORD_LOST) {
+			struct {
+				struct perf_event_header header;
+				__u64 id;
+				__u64 lost;
+			} *lost = (void *) e;
+			printf("lost %lld events\n", lost->lost);
+		} else {
+			printf("unknown event type=%d size=%d\n",
+			       e->header.type, e->header.size);
+		}
+	}
+
+	__sync_synchronize(); /* smp_mb() */
+	header->data_tail = data_head;
+}
+
+static __u64 time_get_ns(void)
+{
+	struct timespec ts;
+
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	return ts.tv_sec * 1000000000ull + ts.tv_nsec;
+}
+
+static __u64 start_time;
+
+#define MAX_CNT 100000ll
+
+static void print_bpf_output(void *data, int size)
+{
+	static __u64 cnt;
+	struct {
+		__u64 pid;
+		__u64 cookie;
+	} *e = data;
+
+	if (e->cookie != 0x12345678) {
+		printf("BUG pid %llx cookie %llx sized %d\n",
+		       e->pid, e->cookie, size);
+		kill(0, SIGINT);
+	}
+
+	cnt++;
+
+	if (cnt == MAX_CNT) {
+		printf("recv %lld events per sec\n",
+		       MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+		kill(0, SIGINT);
+	}
+}
+
+static void test_bpf_perf_event(void)
+{
+	struct perf_event_attr attr = {
+		.sample_type = PERF_SAMPLE_RAW,
+		.type = PERF_TYPE_SOFTWARE,
+		.config = PERF_COUNT_SW_BPF_OUTPUT,
+	};
+	int key = 0;
+
+	pmu_fd = perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
+
+	assert(pmu_fd >= 0);
+	assert(bpf_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0);
+	ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
+}
+
+int main(int argc, char **argv)
+{
+	char filename[256];
+	FILE *f;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	test_bpf_perf_event();
+
+	if (perf_event_mmap(pmu_fd) < 0)
+		return 1;
+
+	f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
+	(void) f;
+
+	start_time = time_get_ns();
+	for (;;) {
+		perf_event_poll(pmu_fd);
+		perf_event_read(print_bpf_output);
+	}
+
+	return 0;
+}
diff --git a/kernel/samples/bpf/tracex1_kern.c b/kernel/samples/bpf/tracex1_kern.c
index 316204637..3f450a8fa 100644
--- a/kernel/samples/bpf/tracex1_kern.c
+++ b/kernel/samples/bpf/tracex1_kern.c
@@ -29,7 +29,7 @@ int bpf_prog1(struct pt_regs *ctx)
 	int len;
 
 	/* non-portable! works for the given kernel only */
-	skb = (struct sk_buff *) ctx->di;
+	skb = (struct sk_buff *) PT_REGS_PARM1(ctx);
 
 	dev = _(skb->dev);
 
diff --git a/kernel/samples/bpf/tracex2_kern.c b/kernel/samples/bpf/tracex2_kern.c
index 19ec1cfc4..b32367cfb 100644
--- a/kernel/samples/bpf/tracex2_kern.c
+++ b/kernel/samples/bpf/tracex2_kern.c
@@ -27,10 +27,10 @@ int bpf_prog2(struct pt_regs *ctx)
 	long init_val = 1;
 	long *value;
 
-	/* x64 specific: read ip of kfree_skb caller.
+	/* x64/s390x specific: read ip of kfree_skb caller.
 	 * non-portable version of __builtin_return_address(0)
 	 */
-	bpf_probe_read(&loc, sizeof(loc), (void *)ctx->sp);
+	bpf_probe_read(&loc, sizeof(loc), (void *)PT_REGS_RET(ctx));
 
 	value = bpf_map_lookup_elem(&my_map, &loc);
 	if (value)
@@ -62,24 +62,38 @@ static unsigned int log2l(unsigned long v)
 		return log2(v);
 }
 
+struct hist_key {
+	char comm[16];
+	u64 pid_tgid;
+	u64 uid_gid;
+	u32 index;
+};
+
 struct bpf_map_def SEC("maps") my_hist_map = {
-	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(u32),
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(struct hist_key),
 	.value_size = sizeof(long),
-	.max_entries = 64,
+	.max_entries = 1024,
 };
 
 SEC("kprobe/sys_write")
 int bpf_prog3(struct pt_regs *ctx)
 {
-	long write_size = ctx->dx; /* arg3 */
+	long write_size = PT_REGS_PARM3(ctx);
 	long init_val = 1;
 	long *value;
-	u32 index = log2l(write_size);
+	struct hist_key key = {};
+
+	key.index = log2l(write_size);
+	key.pid_tgid = bpf_get_current_pid_tgid();
+	key.uid_gid = bpf_get_current_uid_gid();
+	bpf_get_current_comm(&key.comm, sizeof(key.comm));
 
-	value = bpf_map_lookup_elem(&my_hist_map, &index);
+	value = bpf_map_lookup_elem(&my_hist_map, &key);
 	if (value)
 		__sync_fetch_and_add(value, 1);
+	else
+		bpf_map_update_elem(&my_hist_map, &key, &init_val, BPF_ANY);
 	return 0;
 }
 char _license[] SEC("license") = "GPL";
diff --git a/kernel/samples/bpf/tracex2_user.c b/kernel/samples/bpf/tracex2_user.c
index 91b8d0896..cd0241c14 100644
--- a/kernel/samples/bpf/tracex2_user.c
+++ b/kernel/samples/bpf/tracex2_user.c
@@ -3,6 +3,7 @@
 #include <stdlib.h>
 #include <signal.h>
 #include <linux/bpf.h>
+#include <string.h>
 #include "libbpf.h"
 #include "bpf_load.h"
 
@@ -20,23 +21,42 @@ static void stars(char *str, long val, long max, int width)
 	str[i] = '\0';
 }
 
-static void print_hist(int fd)
+struct task {
+	char comm[16];
+	__u64 pid_tgid;
+	__u64 uid_gid;
+};
+
+struct hist_key {
+	struct task t;
+	__u32 index;
+};
+
+#define SIZE sizeof(struct task)
+
+static void print_hist_for_pid(int fd, void *task)
 {
-	int key;
+	struct hist_key key = {}, next_key;
+	char starstr[MAX_STARS];
 	long value;
 	long data[MAX_INDEX] = {};
-	char starstr[MAX_STARS];
-	int i;
 	int max_ind = -1;
 	long max_value = 0;
+	int i, ind;
 
-	for (key = 0; key < MAX_INDEX; key++) {
-		bpf_lookup_elem(fd, &key, &value);
-		data[key] = value;
-		if (value && key > max_ind)
-			max_ind = key;
+	while (bpf_get_next_key(fd, &key, &next_key) == 0) {
+		if (memcmp(&next_key, task, SIZE)) {
+			key = next_key;
+			continue;
+		}
+		bpf_lookup_elem(fd, &next_key, &value);
+		ind = next_key.index;
+		data[ind] = value;
+		if (value && ind > max_ind)
+			max_ind = ind;
 		if (value > max_value)
 			max_value = value;
+		key = next_key;
 	}
 
 	printf("           syscall write() stats\n");
@@ -48,6 +68,35 @@ static void print_hist(int fd)
 		       MAX_STARS, starstr);
 	}
 }
+
+static void print_hist(int fd)
+{
+	struct hist_key key = {}, next_key;
+	static struct task tasks[1024];
+	int task_cnt = 0;
+	int i;
+
+	while (bpf_get_next_key(fd, &key, &next_key) == 0) {
+		int found = 0;
+
+		for (i = 0; i < task_cnt; i++)
+			if (memcmp(&tasks[i], &next_key, SIZE) == 0)
+				found = 1;
+		if (!found)
+			memcpy(&tasks[task_cnt++], &next_key, SIZE);
+		key = next_key;
+	}
+
+	for (i = 0; i < task_cnt; i++) {
+		printf("\npid %d cmd %s uid %d\n",
+		       (__u32) tasks[i].pid_tgid,
+		       tasks[i].comm,
+		       (__u32) tasks[i].uid_gid);
+		print_hist_for_pid(fd, &tasks[i]);
+	}
+
+}
+
 static void int_exit(int sig)
 {
 	print_hist(map_fd[1]);
diff --git a/kernel/samples/bpf/tracex3_kern.c b/kernel/samples/bpf/tracex3_kern.c
index 255ff2792..bf337fbb0 100644
--- a/kernel/samples/bpf/tracex3_kern.c
+++ b/kernel/samples/bpf/tracex3_kern.c
@@ -23,7 +23,7 @@ struct bpf_map_def SEC("maps") my_map = {
 SEC("kprobe/blk_mq_start_request")
 int bpf_prog1(struct pt_regs *ctx)
 {
-	long rq = ctx->di;
+	long rq = PT_REGS_PARM1(ctx);
 	u64 val = bpf_ktime_get_ns();
 
 	bpf_map_update_elem(&my_map, &rq, &val, BPF_ANY);
@@ -51,7 +51,7 @@ struct bpf_map_def SEC("maps") lat_map = {
 SEC("kprobe/blk_update_request")
 int bpf_prog2(struct pt_regs *ctx)
 {
-	long rq = ctx->di;
+	long rq = PT_REGS_PARM1(ctx);
 	u64 *value, l, base;
 	u32 index;
 
diff --git a/kernel/samples/bpf/tracex4_kern.c b/kernel/samples/bpf/tracex4_kern.c
index 126b80512..ac4671420 100644
--- a/kernel/samples/bpf/tracex4_kern.c
+++ b/kernel/samples/bpf/tracex4_kern.c
@@ -27,7 +27,7 @@ struct bpf_map_def SEC("maps") my_map = {
 SEC("kprobe/kmem_cache_free")
 int bpf_prog1(struct pt_regs *ctx)
 {
-	long ptr = ctx->si;
+	long ptr = PT_REGS_PARM2(ctx);
 
 	bpf_map_delete_elem(&my_map, &ptr);
 	return 0;
@@ -36,11 +36,11 @@ int bpf_prog1(struct pt_regs *ctx)
 SEC("kretprobe/kmem_cache_alloc_node")
 int bpf_prog2(struct pt_regs *ctx)
 {
-	long ptr = ctx->ax;
+	long ptr = PT_REGS_RC(ctx);
 	long ip = 0;
 
 	/* get ip address of kmem_cache_alloc_node() caller */
-	bpf_probe_read(&ip, sizeof(ip), (void *)(ctx->bp + sizeof(ip)));
+	bpf_probe_read(&ip, sizeof(ip), (void *)(PT_REGS_FP(ctx) + sizeof(ip)));
 
 	struct pair v = {
 		.val = bpf_ktime_get_ns(),
diff --git a/kernel/samples/bpf/tracex5_kern.c b/kernel/samples/bpf/tracex5_kern.c
new file mode 100644
index 000000000..b3f4295bf
--- /dev/null
+++ b/kernel/samples/bpf/tracex5_kern.c
@@ -0,0 +1,75 @@
+/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/ptrace.h>
+#include <linux/version.h>
+#include <uapi/linux/bpf.h>
+#include <uapi/linux/seccomp.h>
+#include "bpf_helpers.h"
+
+#define PROG(F) SEC("kprobe/"__stringify(F)) int bpf_func_##F
+
+struct bpf_map_def SEC("maps") progs = {
+	.type = BPF_MAP_TYPE_PROG_ARRAY,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(u32),
+	.max_entries = 1024,
+};
+
+SEC("kprobe/seccomp_phase1")
+int bpf_prog1(struct pt_regs *ctx)
+{
+	struct seccomp_data sd = {};
+
+	bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM1(ctx));
+
+	/* dispatch into next BPF program depending on syscall number */
+	bpf_tail_call(ctx, &progs, sd.nr);
+
+	/* fall through -> unknown syscall */
+	if (sd.nr >= __NR_getuid && sd.nr <= __NR_getsid) {
+		char fmt[] = "syscall=%d (one of get/set uid/pid/gid)\n";
+		bpf_trace_printk(fmt, sizeof(fmt), sd.nr);
+	}
+	return 0;
+}
+
+/* we jump here when syscall number == __NR_write */
+PROG(__NR_write)(struct pt_regs *ctx)
+{
+	struct seccomp_data sd = {};
+
+	bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM1(ctx));
+	if (sd.args[2] == 512) {
+		char fmt[] = "write(fd=%d, buf=%p, size=%d)\n";
+		bpf_trace_printk(fmt, sizeof(fmt),
+				 sd.args[0], sd.args[1], sd.args[2]);
+	}
+	return 0;
+}
+
+PROG(__NR_read)(struct pt_regs *ctx)
+{
+	struct seccomp_data sd = {};
+
+	bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM1(ctx));
+	if (sd.args[2] > 128 && sd.args[2] <= 1024) {
+		char fmt[] = "read(fd=%d, buf=%p, size=%d)\n";
+		bpf_trace_printk(fmt, sizeof(fmt),
+				 sd.args[0], sd.args[1], sd.args[2]);
+	}
+	return 0;
+}
+
+PROG(__NR_mmap)(struct pt_regs *ctx)
+{
+	char fmt[] = "mmap\n";
+	bpf_trace_printk(fmt, sizeof(fmt));
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/kernel/samples/bpf/tracex5_user.c b/kernel/samples/bpf/tracex5_user.c
new file mode 100644
index 000000000..a04dd3cd4
--- /dev/null
+++ b/kernel/samples/bpf/tracex5_user.c
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <linux/bpf.h>
+#include <unistd.h>
+#include <linux/filter.h>
+#include <linux/seccomp.h>
+#include <sys/prctl.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+/* install fake seccomp program to enable seccomp code path inside the kernel,
+ * so that our kprobe attached to seccomp_phase1() can be triggered
+ */
+static void install_accept_all_seccomp(void)
+{
+	struct sock_filter filter[] = {
+		BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
+	};
+	struct sock_fprog prog = {
+		.len = (unsigned short)(sizeof(filter)/sizeof(filter[0])),
+		.filter = filter,
+	};
+	if (prctl(PR_SET_SECCOMP, 2, &prog))
+		perror("prctl");
+}
+
+int main(int ac, char **argv)
+{
+	FILE *f;
+	char filename[256];
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	install_accept_all_seccomp();
+
+	f = popen("dd if=/dev/zero of=/dev/null count=5", "r");
+	(void) f;
+
+	read_trace_pipe();
+
+	return 0;
+}
diff --git a/kernel/samples/bpf/tracex6_kern.c b/kernel/samples/bpf/tracex6_kern.c
new file mode 100644
index 000000000..be479c4af
--- /dev/null
+++ b/kernel/samples/bpf/tracex6_kern.c
@@ -0,0 +1,27 @@
+#include <linux/ptrace.h>
+#include <linux/version.h>
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") my_map = {
+	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(u32),
+	.max_entries = 32,
+};
+
+SEC("kprobe/sys_write")
+int bpf_prog1(struct pt_regs *ctx)
+{
+	u64 count;
+	u32 key = bpf_get_smp_processor_id();
+	char fmt[] = "CPU-%d   %llu\n";
+
+	count = bpf_perf_event_read(&my_map, key);
+	bpf_trace_printk(fmt, sizeof(fmt), key, count);
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/kernel/samples/bpf/tracex6_user.c b/kernel/samples/bpf/tracex6_user.c
new file mode 100644
index 000000000..8ea4976cf
--- /dev/null
+++ b/kernel/samples/bpf/tracex6_user.c
@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+#include <linux/perf_event.h>
+#include <linux/bpf.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define SAMPLE_PERIOD  0x7fffffffffffffffULL
+
+static void test_bpf_perf_event(void)
+{
+	int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	int *pmu_fd = malloc(nr_cpus * sizeof(int));
+	int status, i;
+
+	struct perf_event_attr attr_insn_pmu = {
+		.freq = 0,
+		.sample_period = SAMPLE_PERIOD,
+		.inherit = 0,
+		.type = PERF_TYPE_HARDWARE,
+		.read_format = 0,
+		.sample_type = 0,
+		.config = 0,/* PMU: cycles */
+	};
+
+	for (i = 0; i < nr_cpus; i++) {
+		pmu_fd[i] = perf_event_open(&attr_insn_pmu, -1/*pid*/, i/*cpu*/, -1/*group_fd*/, 0);
+		if (pmu_fd[i] < 0) {
+			printf("event syscall failed\n");
+			goto exit;
+		}
+
+		bpf_update_elem(map_fd[0], &i, &pmu_fd[i], BPF_ANY);
+		ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0);
+	}
+
+	status = system("ls > /dev/null");
+	if (status)
+		goto exit;
+	status = system("sleep 2");
+	if (status)
+		goto exit;
+
+exit:
+	for (i = 0; i < nr_cpus; i++)
+		close(pmu_fd[i]);
+	close(map_fd[0]);
+	free(pmu_fd);
+}
+
+int main(int argc, char **argv)
+{
+	char filename[256];
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	test_bpf_perf_event();
+	read_trace_pipe();
+
+	return 0;
+}