Merge branch into tip/master: 'perf/merge'

 # New commits in perf/merge:
    3eaa50e1e255 ("x86/cpu: Hide and rename static_cpu_has()")
    edda9051e267 ("perf/x86/amd/uncore: Add group validation")
    d7ebbae57de3 ("selftests/bpf: Add tests for forked/cloned optimized uprobes")
    eccf368562bb ("selftests/bpf: Add tests for uprobe nop10 red zone clobbering")
    28d57db3e8d4 ("selftests/bpf: Add reattach tests for uprobe syscall")
    b2cf7c41e4f1 ("selftests/bpf: Change uprobe/usdt trigger bench code to use nop10")
    ec0596a02083 ("selftests/bpf: Change uprobe syscall tests to use nop10")
    6d91200bcbb5 ("selftests/bpf: Emit nop,nop10 instructions combo for x86_64 arch")
    8cae54c58608 ("libbpf: Detect uprobe syscall with new error")
    ee2862439e5c ("libbpf: Change has_nop_combo to work on top of nop10")
    554ba38456da ("uprobes/x86: Move optimized uprobe from nop5 to nop10")
    d9a48e77f6fe ("uprobes/x86: Allow to copy uprobe trampolines on fork")
    07c308eb2bcf ("uprobes/x86: Do not leak trampoline vma mapping on optimization failure")
    38af0dd6a266 ("uprobes/x86: Remove struct uprobe_trampoline object")
    a4573a3838ae ("perf/core: Check kernel access when kernel callchains are requested")
    166f10836a65 ("perf/core: Fix kernel register info leak via hardware skid")
    a6b5fbc33172 ("perf/x86/intel: Drop fixed-counter PEBS constraints for baseline PEBS")
    01c153956b44 ("perf/x86/intel: Validate the return value of intel_pmu_init_hybrid()")
    e2b0575900ff ("perf/x86/intel: Fix kernel address leakages in LBR stack")
    170cc6b02e3d ("perf/x86/intel: Fallback to sw branch type decoding if no hw decoding")
    3c4ec9b2a5db ("perf/x86/intel: Keep cap_user_rdpmc in sync with RDPMC user-disable state")
    8767b4d73018 ("perf/x86/intel: Remove anythread_deprecated bit from perf_capabilities")
    b25813b17944 ("perf/x86/intel/uncore: Implement lazy setup for MSR/MMIO PMUs")
    174f0582e38a ("perf/x86/intel/uncore: Fix uncore_box ref/unref ordering")
    30c0a1095652 ("perf/x86/intel/uncore: Introduce PMU flags and broken state")
    ae7ca8796dda ("perf/x86/intel/uncore: Factor out box setup code")
    3012af7df343 ("perf/x86/intel/uncore: Keep PCI PMUs working when MMIO/MSR setup fails")
    cbbc25209ce3 ("perf/x86/intel/uncore: Let init_box() callback report failures")
    7d3a9ff98898 ("perf/x86/intel/uncore: Fix refcnt and other cleanups")
    003267cb94e2 ("perf/x86/intel/uncore: Fix PCI PMU cleanup on setup failure")

Signed-off-by: Ingo Molnar <mingo@kernel.org>

8 files changed, 436 insertions, 65 deletions

diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c
index 3d9d2cd7764b..c4a3a6b3eb83 100644
--- a/tools/testing/selftests/bpf/bench.c
+++ b/tools/testing/selftests/bpf/bench.c
@@ -539,12 +539,12 @@ extern const struct bench bench_trig_uretprobe_multi_push;
 extern const struct bench bench_trig_uprobe_multi_ret;
 extern const struct bench bench_trig_uretprobe_multi_ret;
 #ifdef __x86_64__
-extern const struct bench bench_trig_uprobe_nop5;
-extern const struct bench bench_trig_uretprobe_nop5;
-extern const struct bench bench_trig_uprobe_multi_nop5;
-extern const struct bench bench_trig_uretprobe_multi_nop5;
+extern const struct bench bench_trig_uprobe_nop10;
+extern const struct bench bench_trig_uretprobe_nop10;
+extern const struct bench bench_trig_uprobe_multi_nop10;
+extern const struct bench bench_trig_uretprobe_multi_nop10;
 extern const struct bench bench_trig_usdt_nop;
-extern const struct bench bench_trig_usdt_nop5;
+extern const struct bench bench_trig_usdt_nop10;
 #endif
 
 extern const struct bench bench_rb_libbpf;
@@ -622,12 +622,12 @@ static const struct bench *benchs[] = {
 	&bench_trig_uprobe_multi_ret,
 	&bench_trig_uretprobe_multi_ret,
 #ifdef __x86_64__
-	&bench_trig_uprobe_nop5,
-	&bench_trig_uretprobe_nop5,
-	&bench_trig_uprobe_multi_nop5,
-	&bench_trig_uretprobe_multi_nop5,
+	&bench_trig_uprobe_nop10,
+	&bench_trig_uretprobe_nop10,
+	&bench_trig_uprobe_multi_nop10,
+	&bench_trig_uretprobe_multi_nop10,
 	&bench_trig_usdt_nop,
-	&bench_trig_usdt_nop5,
+	&bench_trig_usdt_nop10,
 #endif
 	/* ringbuf/perfbuf benchmarks */
 	&bench_rb_libbpf,
diff --git a/tools/testing/selftests/bpf/benchs/bench_trigger.c b/tools/testing/selftests/bpf/benchs/bench_trigger.c
index 2f22ec61667b..61513efc167a 100644
--- a/tools/testing/selftests/bpf/benchs/bench_trigger.c
+++ b/tools/testing/selftests/bpf/benchs/bench_trigger.c
@@ -396,15 +396,15 @@ static void *uprobe_producer_ret(void *input)
 }
 
 #ifdef __x86_64__
-__nocf_check __weak void uprobe_target_nop5(void)
+__nocf_check __weak void uprobe_target_nop10(void)
 {
-	asm volatile (".byte 0x0f, 0x1f, 0x44, 0x00, 0x00");
+	asm volatile (".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00");
 }
 
-static void *uprobe_producer_nop5(void *input)
+static void *uprobe_producer_nop10(void *input)
 {
 	while (true)
-		uprobe_target_nop5();
+		uprobe_target_nop10();
 	return NULL;
 }
 
@@ -418,7 +418,7 @@ static void *uprobe_producer_usdt_nop(void *input)
 	return NULL;
 }
 
-static void *uprobe_producer_usdt_nop5(void *input)
+static void *uprobe_producer_usdt_nop10(void *input)
 {
 	while (true)
 		usdt_2();
@@ -542,24 +542,24 @@ static void uretprobe_multi_ret_setup(void)
 }
 
 #ifdef __x86_64__
-static void uprobe_nop5_setup(void)
+static void uprobe_nop10_setup(void)
 {
-	usetup(false, false /* !use_multi */, &uprobe_target_nop5);
+	usetup(false, false /* !use_multi */, &uprobe_target_nop10);
 }
 
-static void uretprobe_nop5_setup(void)
+static void uretprobe_nop10_setup(void)
 {
-	usetup(true, false /* !use_multi */, &uprobe_target_nop5);
+	usetup(true, false /* !use_multi */, &uprobe_target_nop10);
 }
 
-static void uprobe_multi_nop5_setup(void)
+static void uprobe_multi_nop10_setup(void)
 {
-	usetup(false, true /* use_multi */, &uprobe_target_nop5);
+	usetup(false, true /* use_multi */, &uprobe_target_nop10);
 }
 
-static void uretprobe_multi_nop5_setup(void)
+static void uretprobe_multi_nop10_setup(void)
 {
-	usetup(true, true /* use_multi */, &uprobe_target_nop5);
+	usetup(true, true /* use_multi */, &uprobe_target_nop10);
 }
 
 static void usdt_setup(const char *name)
@@ -598,7 +598,7 @@ static void usdt_nop_setup(void)
 	usdt_setup("usdt_1");
 }
 
-static void usdt_nop5_setup(void)
+static void usdt_nop10_setup(void)
 {
 	usdt_setup("usdt_2");
 }
@@ -665,10 +665,10 @@ BENCH_TRIG_USERMODE(uretprobe_multi_nop, nop, "uretprobe-multi-nop");
 BENCH_TRIG_USERMODE(uretprobe_multi_push, push, "uretprobe-multi-push");
 BENCH_TRIG_USERMODE(uretprobe_multi_ret, ret, "uretprobe-multi-ret");
 #ifdef __x86_64__
-BENCH_TRIG_USERMODE(uprobe_nop5, nop5, "uprobe-nop5");
-BENCH_TRIG_USERMODE(uretprobe_nop5, nop5, "uretprobe-nop5");
-BENCH_TRIG_USERMODE(uprobe_multi_nop5, nop5, "uprobe-multi-nop5");
-BENCH_TRIG_USERMODE(uretprobe_multi_nop5, nop5, "uretprobe-multi-nop5");
+BENCH_TRIG_USERMODE(uprobe_nop10, nop10, "uprobe-nop10");
+BENCH_TRIG_USERMODE(uretprobe_nop10, nop10, "uretprobe-nop10");
+BENCH_TRIG_USERMODE(uprobe_multi_nop10, nop10, "uprobe-multi-nop10");
+BENCH_TRIG_USERMODE(uretprobe_multi_nop10, nop10, "uretprobe-multi-nop10");
 BENCH_TRIG_USERMODE(usdt_nop, usdt_nop, "usdt-nop");
-BENCH_TRIG_USERMODE(usdt_nop5, usdt_nop5, "usdt-nop5");
+BENCH_TRIG_USERMODE(usdt_nop10, usdt_nop10, "usdt-nop10");
 #endif
diff --git a/tools/testing/selftests/bpf/benchs/run_bench_uprobes.sh b/tools/testing/selftests/bpf/benchs/run_bench_uprobes.sh
index 9ec59423b949..e490b337e960 100755
--- a/tools/testing/selftests/bpf/benchs/run_bench_uprobes.sh
+++ b/tools/testing/selftests/bpf/benchs/run_bench_uprobes.sh
@@ -2,7 +2,7 @@
 
 set -eufo pipefail
 
-for i in usermode-count syscall-count {uprobe,uretprobe}-{nop,push,ret,nop5} usdt-nop usdt-nop5
+for i in usermode-count syscall-count {uprobe,uretprobe}-{nop,push,ret,nop10} usdt-nop usdt-nop10
 do
 	summary=$(sudo ./bench -w2 -d5 -a trig-$i | tail -n1 | cut -d'(' -f1 | cut -d' ' -f3-)
 	printf "%-15s: %s\n" $i "$summary"
diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
index 955a37751b52..e193206fc5d2 100644
--- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
@@ -4,6 +4,8 @@
 
 #ifdef __x86_64__
 
+#define _GNU_SOURCE
+#include <sched.h>
 #include <unistd.h>
 #include <asm/ptrace.h>
 #include <linux/compiler.h>
@@ -13,11 +15,12 @@
 #include <sys/syscall.h>
 #include <sys/prctl.h>
 #include <asm/prctl.h>
+#include <stdnoreturn.h>
 #include "uprobe_syscall.skel.h"
 #include "uprobe_syscall_executed.skel.h"
 #include "bpf/libbpf_internal.h"
 
-#define USDT_NOP .byte 0x0f, 0x1f, 0x44, 0x00, 0x00
+#define USDT_NOP .byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
 #include "usdt.h"
 
 #pragma GCC diagnostic ignored "-Wattributes"
@@ -26,7 +29,7 @@ __attribute__((aligned(16)))
 __nocf_check __weak __naked unsigned long uprobe_regs_trigger(void)
 {
 	asm volatile (
-		".byte 0x0f, 0x1f, 0x44, 0x00, 0x00\n" /* nop5 */
+		".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00\n" /* nop10 */
 		"movq $0xdeadbeef, %rax\n"
 		"ret\n"
 	);
@@ -345,9 +348,9 @@ cleanup:
 __attribute__((aligned(16)))
 __nocf_check __weak __naked void uprobe_test(void)
 {
-	asm volatile ("					\n"
-		".byte 0x0f, 0x1f, 0x44, 0x00, 0x00	\n"
-		"ret					\n"
+	asm volatile (
+		".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00\n" /* nop10 */
+		"ret\n"
 	);
 }
 
@@ -357,6 +360,50 @@ __nocf_check __weak void usdt_test(void)
 	USDT(optimized_uprobe, usdt);
 }
 
+/*
+ * Assembly-level red zone clobbering test. Stores known values in the
+ * red zone (below RSP), executes a nop10 (uprobe site), and checks that
+ * the values survived. Returns 0 if intact, 1 if clobbered.
+ *
+ * The nop5 optimization used CALL (which pushes a return address to
+ * [rsp-8]), the value at -8(%rsp) was overwritten. The nop10 optimization
+ * should escape that by moving stackpointer below the redzone before
+ * doing the CALL.
+ *
+ * Align the code at 64 bytes, to make sure nop10 is not on page boundary.
+ */
+__attribute__((aligned(64)))
+__nocf_check __weak __naked unsigned long uprobe_red_zone_test(void)
+{
+	asm volatile (
+		"movabs $0x1111111111111111, %%rax\n"
+		"movq   %%rax, -8(%%rsp)\n"
+		"movabs $0x2222222222222222, %%rax\n"
+		"movq   %%rax, -16(%%rsp)\n"
+		"movabs $0x3333333333333333, %%rax\n"
+		"movq   %%rax, -24(%%rsp)\n"
+
+		".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00\n" /* nop10: uprobe site */
+
+		"movabs $0x1111111111111111, %%rax\n"
+		"cmpq   %%rax, -8(%%rsp)\n"
+		"jne    1f\n"
+		"movabs $0x2222222222222222, %%rax\n"
+		"cmpq   %%rax, -16(%%rsp)\n"
+		"jne    1f\n"
+		"movabs $0x3333333333333333, %%rax\n"
+		"cmpq   %%rax, -24(%%rsp)\n"
+		"jne    1f\n"
+
+		"xorl   %%eax, %%eax\n"
+		"retq\n"
+		"1:\n"
+		"movl   $1, %%eax\n"
+		"retq\n"
+		::: "rax", "memory"
+	);
+}
+
 static int find_uprobes_trampoline(void *tramp_addr)
 {
 	void *start, *end;
@@ -388,14 +435,15 @@ static int find_uprobes_trampoline(void *tramp_addr)
 	return ret;
 }
 
-static unsigned char nop5[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
+static unsigned char nop10[10]  = { 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
+static unsigned char lea_rsp[5] = { 0x48, 0x8d, 0x64, 0x24, 0x80 };
 
-static void *find_nop5(void *fn)
+static void *find_nop10(void *fn)
 {
 	int i;
 
-	for (i = 0; i < 10; i++) {
-		if (!memcmp(nop5, fn + i, 5))
+	for (i = 0; i < 128; i++) {
+		if (!memcmp(nop10, fn + i, 10))
 			return fn + i;
 	}
 	return NULL;
@@ -403,6 +451,16 @@ static void *find_nop5(void *fn)
 
 typedef void (__attribute__((nocf_check)) *trigger_t)(void);
 
+static void check_attach_notrigger(struct uprobe_syscall_executed *skel,
+				   void *addr, int executed)
+{
+	unsigned char *op = addr;
+
+	/* Make sure bpf program was not executed. */
+	ASSERT_EQ(skel->bss->executed, executed, "executed");
+	ASSERT_EQ(*op, 0xcc, "int3");
+}
+
 static void *check_attach(struct uprobe_syscall_executed *skel, trigger_t trigger,
 			  void *addr, int executed)
 {
@@ -420,7 +478,8 @@ static void *check_attach(struct uprobe_syscall_executed *skel, trigger_t trigge
 	ASSERT_EQ(skel->bss->executed, executed, "executed");
 
 	/* .. and check the trampoline is as expected. */
-	call = (struct __arch_relative_insn *) addr;
+	ASSERT_OK(memcmp(addr, lea_rsp, 5), "lea_rsp");
+	call = (struct __arch_relative_insn *)(addr + 5);
 	tramp = (void *) (call + 1) + call->raddr;
 	ASSERT_EQ(call->op, 0xe8, "call");
 	ASSERT_OK(find_uprobes_trampoline(tramp), "uprobes_trampoline");
@@ -428,21 +487,26 @@ static void *check_attach(struct uprobe_syscall_executed *skel, trigger_t trigge
 	return tramp;
 }
 
-static void check_detach(void *addr, void *tramp)
+static bool check_detach(void *addr, void *tramp)
 {
+	static const unsigned char nop10_prefix[] = { 0x66, 0x2e, 0x0f, 0x1f, 0x84 };
+	bool ok = true;
+
 	/* [uprobes_trampoline] stays after detach */
-	ASSERT_OK(find_uprobes_trampoline(tramp), "uprobes_trampoline");
-	ASSERT_OK(memcmp(addr, nop5, 5), "nop5");
+	ok &= ASSERT_OK(find_uprobes_trampoline(tramp), "uprobes_trampoline");
+	ok &= ASSERT_OK(memcmp(addr, nop10_prefix, 5), "nop10_prefix");
+	return ok;
 }
 
-static void check(struct uprobe_syscall_executed *skel, struct bpf_link *link,
-		  trigger_t trigger, void *addr, int executed)
+static void *check(struct uprobe_syscall_executed *skel, struct bpf_link *link,
+		   trigger_t trigger, void *addr, int executed)
 {
 	void *tramp;
 
 	tramp = check_attach(skel, trigger, addr, executed);
 	bpf_link__destroy(link);
 	check_detach(addr, tramp);
+	return tramp;
 }
 
 static void test_uprobe_legacy(void)
@@ -453,6 +517,7 @@ static void test_uprobe_legacy(void)
 	);
 	struct bpf_link *link;
 	unsigned long offset;
+	void *tramp;
 
 	offset = get_uprobe_offset(&uprobe_test);
 	if (!ASSERT_GE(offset, 0, "get_uprobe_offset"))
@@ -470,7 +535,30 @@ static void test_uprobe_legacy(void)
 	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_opts"))
 		goto cleanup;
 
-	check(skel, link, uprobe_test, uprobe_test, 2);
+	tramp = check(skel, link, uprobe_test, uprobe_test, 2);
+
+	/* reattach and detach without triggering optimization */
+	link = bpf_program__attach_uprobe_opts(skel->progs.test_uprobe,
+					       0, "/proc/self/exe", offset, NULL);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_opts"))
+		goto cleanup;
+
+	check_attach_notrigger(skel, uprobe_test, 2);
+
+	bpf_link__destroy(link);
+	if (!check_detach(uprobe_test, tramp))
+		goto cleanup;
+
+	uprobe_test();
+	ASSERT_EQ(skel->bss->executed, 2, "executed_no_probe");
+
+	/* reattach with triggering optimization */
+	link = bpf_program__attach_uprobe_opts(skel->progs.test_uprobe,
+				0, "/proc/self/exe", offset, NULL);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_opts"))
+		goto cleanup;
+
+	check(skel, link, uprobe_test, uprobe_test, 4);
 
 	/* uretprobe */
 	skel->bss->executed = 0;
@@ -492,6 +580,7 @@ static void test_uprobe_multi(void)
 	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts);
 	struct bpf_link *link;
 	unsigned long offset;
+	void *tramp;
 
 	offset = get_uprobe_offset(&uprobe_test);
 	if (!ASSERT_GE(offset, 0, "get_uprobe_offset"))
@@ -512,7 +601,30 @@ static void test_uprobe_multi(void)
 	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
 		goto cleanup;
 
-	check(skel, link, uprobe_test, uprobe_test, 2);
+	tramp = check(skel, link, uprobe_test, uprobe_test, 2);
+
+	/* reattach and detach without triggering optimization */
+	link = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_multi,
+				0, "/proc/self/exe", NULL, &opts);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
+		goto cleanup;
+
+	check_attach_notrigger(skel, uprobe_test, 2);
+
+	bpf_link__destroy(link);
+	if (!check_detach(uprobe_test, tramp))
+		goto cleanup;
+
+	uprobe_test();
+	ASSERT_EQ(skel->bss->executed, 2, "executed_no_probe");
+
+	/* reattach with triggering optimization */
+	link = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_multi,
+				0, "/proc/self/exe", NULL, &opts);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
+		goto cleanup;
+
+	check(skel, link, uprobe_test, uprobe_test, 4);
 
 	/* uretprobe.multi */
 	skel->bss->executed = 0;
@@ -536,6 +648,7 @@ static void test_uprobe_session(void)
 	);
 	struct bpf_link *link;
 	unsigned long offset;
+	void *tramp;
 
 	offset = get_uprobe_offset(&uprobe_test);
 	if (!ASSERT_GE(offset, 0, "get_uprobe_offset"))
@@ -555,7 +668,30 @@ static void test_uprobe_session(void)
 	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
 		goto cleanup;
 
-	check(skel, link, uprobe_test, uprobe_test, 4);
+	tramp = check(skel, link, uprobe_test, uprobe_test, 4);
+
+	/* reattach and detach without triggering optimization */
+	link = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_session,
+				0, "/proc/self/exe", NULL, &opts);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
+		goto cleanup;
+
+	check_attach_notrigger(skel, uprobe_test, 4);
+
+	bpf_link__destroy(link);
+	if (!check_detach(uprobe_test, tramp))
+		goto cleanup;
+
+	uprobe_test();
+	ASSERT_EQ(skel->bss->executed, 4, "executed_no_probe");
+
+	/* reattach with triggering optimization */
+	link = bpf_program__attach_uprobe_multi(skel->progs.test_uprobe_session,
+				0, "/proc/self/exe", NULL, &opts);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
+		goto cleanup;
+
+	check(skel, link, uprobe_test, uprobe_test, 8);
 
 cleanup:
 	uprobe_syscall_executed__destroy(skel);
@@ -565,11 +701,11 @@ static void test_uprobe_usdt(void)
 {
 	struct uprobe_syscall_executed *skel;
 	struct bpf_link *link;
-	void *addr;
+	void *addr, *tramp;
 
 	errno = 0;
-	addr = find_nop5(usdt_test);
-	if (!ASSERT_OK_PTR(addr, "find_nop5"))
+	addr = find_nop10(usdt_test);
+	if (!ASSERT_OK_PTR(addr, "find_nop10"))
 		return;
 
 	skel = uprobe_syscall_executed__open_and_load();
@@ -584,7 +720,32 @@ static void test_uprobe_usdt(void)
 	if (!ASSERT_OK_PTR(link, "bpf_program__attach_usdt"))
 		goto cleanup;
 
-	check(skel, link, usdt_test, addr, 2);
+	tramp = check(skel, link, usdt_test, addr, 2);
+
+	/* reattach and detach without triggering optimization */
+	link = bpf_program__attach_usdt(skel->progs.test_usdt,
+				-1 /* all PIDs */, "/proc/self/exe",
+				"optimized_uprobe", "usdt", NULL);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_usdt"))
+		goto cleanup;
+
+	check_attach_notrigger(skel, addr, 2);
+
+	bpf_link__destroy(link);
+	if (!check_detach(addr, tramp))
+		goto cleanup;
+
+	usdt_test();
+	ASSERT_EQ(skel->bss->executed, 2, "executed_no_probe");
+
+	/* reattach with triggering optimization */
+	link = bpf_program__attach_usdt(skel->progs.test_usdt,
+				-1 /* all PIDs */, "/proc/self/exe",
+				"optimized_uprobe", "usdt", NULL);
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_usdt"))
+		goto cleanup;
+
+	check(skel, link, usdt_test, addr, 4);
 
 cleanup:
 	uprobe_syscall_executed__destroy(skel);
@@ -757,12 +918,124 @@ cleanup:
 #define __NR_uprobe 336
 #endif
 
+static void test_uprobe_red_zone(void)
+{
+	struct uprobe_syscall_executed *skel;
+	struct bpf_link *link;
+	void *nop10_addr;
+	size_t offset;
+	int i;
+
+	nop10_addr = find_nop10(uprobe_red_zone_test);
+	if (!ASSERT_NEQ(nop10_addr, NULL, "find_nop10"))
+		return;
+
+	skel = uprobe_syscall_executed__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "open_and_load"))
+		return;
+
+	offset = get_uprobe_offset(nop10_addr);
+	link = bpf_program__attach_uprobe_opts(skel->progs.test_uprobe,
+			0, "/proc/self/exe", offset, NULL);
+	if (!ASSERT_OK_PTR(link, "attach_uprobe"))
+		goto cleanup;
+
+	for (i = 0; i < 10; i++)
+		ASSERT_EQ(uprobe_red_zone_test(), 0, "red_zone_intact");
+
+	bpf_link__destroy(link);
+
+cleanup:
+	uprobe_syscall_executed__destroy(skel);
+}
+
 static void test_uprobe_error(void)
 {
 	long err = syscall(__NR_uprobe);
 
 	ASSERT_EQ(err, -1, "error");
-	ASSERT_EQ(errno, ENXIO, "errno");
+	ASSERT_EQ(errno, EPROTO, "errno");
+}
+
+__attribute__((aligned(16)))
+__nocf_check __weak __naked void uprobe_fork_test(void)
+{
+	asm volatile (
+		".byte 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00\n" /* nop10 */
+		"ret\n"
+	);
+}
+
+static noreturn int child_func(void *arg)
+{
+	struct uprobe_syscall_executed *skel = arg;
+
+	/* Make sure the child's probe is still there and optimized.. */
+	if (memcmp(uprobe_fork_test, lea_rsp, sizeof(lea_rsp)))
+		_exit(1);
+
+	skel->bss->pid = getpid();
+
+	/* .. and it executes properly. */
+	uprobe_fork_test();
+
+	if (skel->bss->executed != 3)
+		_exit(2);
+
+	_exit(0);
+}
+
+static void test_uprobe_fork_optimized(bool clone_vm)
+{
+	struct uprobe_syscall_executed *skel = NULL;
+	unsigned long offset;
+	int pid, status, err;
+	char stack[65535];
+
+	offset = get_uprobe_offset(&uprobe_fork_test);
+	if (!ASSERT_GE(offset, 0, "get_uprobe_offset"))
+		return;
+
+	skel = uprobe_syscall_executed__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "open_and_load"))
+		goto cleanup;
+
+	skel->links.test_uprobe = bpf_program__attach_uprobe_opts(skel->progs.test_uprobe,
+					-1, "/proc/self/exe", offset, NULL);
+	if (!ASSERT_OK_PTR(skel->links.test_uprobe, "attach_uprobe"))
+		goto cleanup;
+
+	skel->bss->pid = getpid();
+
+	/* Trigger optimization of uprobe in uprobe_fork_test.  */
+	uprobe_fork_test();
+	uprobe_fork_test();
+
+	/* Make sure it got optimied. */
+	if (!ASSERT_OK(memcmp(uprobe_fork_test, lea_rsp, sizeof(lea_rsp)), "optimized"))
+		goto cleanup;
+
+	if (clone_vm) {
+		pid = clone(child_func, stack + sizeof(stack), CLONE_VM|SIGCHLD, skel);
+		if (!ASSERT_GT(pid, 0, "clone"))
+			goto cleanup;
+	} else {
+		pid = fork();
+		if (!ASSERT_GE(pid, 0, "fork"))
+			goto cleanup;
+		if (pid == 0)
+			child_func(skel);
+	}
+
+	/* Wait for the child and verify it exited properly with 0. */
+	err = waitpid(pid, &status, 0);
+	if (ASSERT_EQ(err, pid, "waitpid")) {
+		ASSERT_EQ(WIFEXITED(status), 1, "child_exited");
+		ASSERT_EQ(WEXITSTATUS(status), 0, "child_exit_code");
+	}
+
+cleanup:
+	uprobe_syscall_executed__destroy(skel);
 }
 
 static void __test_uprobe_syscall(void)
@@ -783,6 +1056,12 @@ static void __test_uprobe_syscall(void)
 		test_uprobe_usdt();
 	if (test__start_subtest("uprobe_race"))
 		test_uprobe_race();
+	if (test__start_subtest("uprobe_red_zone"))
+		test_uprobe_red_zone();
+	if (test__start_subtest("uprobe_optimized_fork"))
+		test_uprobe_fork_optimized(false);
+	if (test__start_subtest("uprobe_optimized_clone_vm"))
+		test_uprobe_fork_optimized(true);
 	if (test__start_subtest("uprobe_error"))
 		test_uprobe_error();
 	if (test__start_subtest("uprobe_regs_equal"))
diff --git a/tools/testing/selftests/bpf/prog_tests/usdt.c b/tools/testing/selftests/bpf/prog_tests/usdt.c
index 69759b27794d..8004c9568ffa 100644
--- a/tools/testing/selftests/bpf/prog_tests/usdt.c
+++ b/tools/testing/selftests/bpf/prog_tests/usdt.c
@@ -250,9 +250,10 @@ cleanup:
 #ifdef __x86_64__
 extern void usdt_1(void);
 extern void usdt_2(void);
+extern void usdt_red_zone_trigger(void);
 
 static unsigned char nop1[1] = { 0x90 };
-static unsigned char nop1_nop5_combo[6] = { 0x90, 0x0f, 0x1f, 0x44, 0x00, 0x00 };
+static unsigned char nop1_nop10_combo[11] = { 0x90, 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 };
 
 static void *find_instr(void *fn, unsigned char *instr, size_t cnt)
 {
@@ -271,17 +272,17 @@ static void subtest_optimized_attach(void)
 	__u8 *addr_1, *addr_2;
 
 	/* usdt_1 USDT probe has single nop instruction */
-	addr_1 = find_instr(usdt_1, nop1_nop5_combo, 6);
-	if (!ASSERT_NULL(addr_1, "usdt_1_find_nop1_nop5_combo"))
+	addr_1 = find_instr(usdt_1, nop1_nop10_combo, 11);
+	if (!ASSERT_NULL(addr_1, "usdt_1_find_nop1_nop10_combo"))
 		return;
 
 	addr_1 = find_instr(usdt_1, nop1, 1);
 	if (!ASSERT_OK_PTR(addr_1, "usdt_1_find_nop1"))
 		return;
 
-	/* usdt_2 USDT probe has nop,nop5 instructions combo */
-	addr_2 = find_instr(usdt_2, nop1_nop5_combo, 6);
-	if (!ASSERT_OK_PTR(addr_2, "usdt_2_find_nop1_nop5_combo"))
+	/* usdt_2 USDT probe has nop,nop10 instructions combo */
+	addr_2 = find_instr(usdt_2, nop1_nop10_combo, 11);
+	if (!ASSERT_OK_PTR(addr_2, "usdt_2_find_nop1_nop10_combo"))
 		return;
 
 	skel = test_usdt__open_and_load();
@@ -309,12 +310,12 @@ static void subtest_optimized_attach(void)
 
 	bpf_link__destroy(skel->links.usdt_executed);
 
-	/* we expect the nop5 ip */
+	/* we expect the nop10 ip */
 	skel->bss->expected_ip = (unsigned long) addr_2 + 1;
 
 	/*
 	 * Attach program on top of usdt_2 which is probe defined on top
-	 * of nop1,nop5 combo, so the probe gets optimized on top of nop5.
+	 * of nop1,nop10 combo, so the probe gets optimized on top of nop10.
 	 */
 	skel->links.usdt_executed = bpf_program__attach_usdt(skel->progs.usdt_executed,
 						     0 /*self*/, "/proc/self/exe",
@@ -328,13 +329,64 @@ static void subtest_optimized_attach(void)
 	/* nop stays on addr_2 address */
 	ASSERT_EQ(*addr_2, 0x90, "nop");
 
-	/* call is on addr_2 + 1 address */
-	ASSERT_EQ(*(addr_2 + 1), 0xe8, "call");
+	/*
+	 * lea -0x80(%rsp), %rsp
+	 * call ...
+	 */
+	static unsigned char expected[] = { 0x48, 0x8d, 0x64, 0x24, 0x80, 0xe8 };
+
+	ASSERT_MEMEQ(addr_2 + 1, expected, sizeof(expected), "lea_and_call");
 	ASSERT_EQ(skel->bss->executed, 4, "executed");
 
 cleanup:
 	test_usdt__destroy(skel);
 }
+
+/*
+ * Test that USDT arguments survive nop10 optimization in a function where
+ * the compiler places operands in the red zone.
+ *
+ * Signal handlers are prone to having the compiler place USDT argument
+ * operands in the red zone (below rsp).
+ *
+ * The nop5 optimization used CALL (which pushes a return address to
+ * [rsp-8]), the value at -8(%rsp) was overwritten. The nop10 optimization
+ * should escape that by moving stackpointer below the redzone before
+ * doing the CALL.
+ */
+static void subtest_optimized_red_zone(void)
+{
+	struct test_usdt *skel;
+	int i;
+
+	skel = test_usdt__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "open_and_load"))
+		return;
+
+	skel->bss->expected_arg[0] = 0xDEADBEEF;
+	skel->bss->expected_arg[1] = 0xCAFEBABE;
+	skel->bss->expected_arg[2] = 0xFEEDFACE;
+	skel->bss->expected_pid = getpid();
+
+	skel->links.usdt_check_arg = bpf_program__attach_usdt(
+		skel->progs.usdt_check_arg, 0, "/proc/self/exe",
+		"optimized_attach", "usdt_red_zone", NULL);
+	if (!ASSERT_OK_PTR(skel->links.usdt_check_arg, "attach_usdt_red_zone"))
+		goto cleanup;
+
+	for (i = 0; i < 10; i++)
+		usdt_red_zone_trigger();
+
+	ASSERT_EQ(skel->bss->arg_total, 10, "arg_total");
+	ASSERT_EQ(skel->bss->arg_bad, 0, "arg_bad");
+	ASSERT_EQ(skel->bss->arg_last[0], 0xDEADBEEF, "arg_last_1");
+	ASSERT_EQ(skel->bss->arg_last[1], 0xCAFEBABE, "arg_last_2");
+	ASSERT_EQ(skel->bss->arg_last[2], 0xFEEDFACE, "arg_last_3");
+
+cleanup:
+	test_usdt__destroy(skel);
+}
+
 #endif
 
 unsigned short test_usdt_100_semaphore SEC(".probes");
@@ -608,6 +660,8 @@ void test_usdt(void)
 		subtest_basic_usdt(true);
 	if (test__start_subtest("optimized_attach"))
 		subtest_optimized_attach();
+	if (test__start_subtest("optimized_red_zone"))
+		subtest_optimized_red_zone();
 #endif
 	if (test__start_subtest("multispec"))
 		subtest_multispec_usdt();
diff --git a/tools/testing/selftests/bpf/progs/test_usdt.c b/tools/testing/selftests/bpf/progs/test_usdt.c
index f00cb52874e0..0ee78fb050a1 100644
--- a/tools/testing/selftests/bpf/progs/test_usdt.c
+++ b/tools/testing/selftests/bpf/progs/test_usdt.c
@@ -149,5 +149,30 @@ int usdt_executed(struct pt_regs *ctx)
 		executed++;
 	return 0;
 }
+
+int arg_total;
+int arg_bad;
+long arg_last[3];
+long expected_arg[3];
+int expected_pid;
+
+SEC("usdt")
+int BPF_USDT(usdt_check_arg, long arg1, long arg2, long arg3)
+{
+	if (expected_pid != (bpf_get_current_pid_tgid() >> 32))
+		return 0;
+
+	__sync_fetch_and_add(&arg_total, 1);
+	arg_last[0] = arg1;
+	arg_last[1] = arg2;
+	arg_last[2] = arg3;
+
+	if (arg1 != expected_arg[0] ||
+	    arg2 != expected_arg[1] ||
+	    arg3 != expected_arg[2])
+		__sync_fetch_and_add(&arg_bad, 1);
+
+	return 0;
+}
 #endif
 char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/usdt.h b/tools/testing/selftests/bpf/usdt.h
index c71e21df38b3..75687f50f4e2 100644
--- a/tools/testing/selftests/bpf/usdt.h
+++ b/tools/testing/selftests/bpf/usdt.h
@@ -313,7 +313,7 @@ struct usdt_sema { volatile unsigned short active; };
 #if defined(__ia64__) || defined(__s390__) || defined(__s390x__)
 #define USDT_NOP			nop 0
 #elif defined(__x86_64__)
-#define USDT_NOP                       .byte 0x90, 0x0f, 0x1f, 0x44, 0x00, 0x0 /* nop, nop5 */
+#define USDT_NOP                       .byte 0x90, 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 /* nop, nop10 */
 #else
 #define USDT_NOP			nop
 #endif
diff --git a/tools/testing/selftests/bpf/usdt_2.c b/tools/testing/selftests/bpf/usdt_2.c
index 789883aaca4c..5e38f8605b02 100644
--- a/tools/testing/selftests/bpf/usdt_2.c
+++ b/tools/testing/selftests/bpf/usdt_2.c
@@ -3,7 +3,7 @@
 #if defined(__x86_64__)
 
 /*
- * Include usdt.h with default nop,nop5 instructions combo.
+ * Include usdt.h with default nop,nop10 instructions combo.
  */
 #include "usdt.h"
 
@@ -13,4 +13,17 @@ void usdt_2(void)
 	USDT(optimized_attach, usdt_2);
 }
 
+static volatile unsigned long usdt_red_zone_arg1 = 0xDEADBEEF;
+static volatile unsigned long usdt_red_zone_arg2 = 0xCAFEBABE;
+static volatile unsigned long usdt_red_zone_arg3 = 0xFEEDFACE;
+
+void __attribute__((noinline)) usdt_red_zone_trigger(void)
+{
+	unsigned long a1 = usdt_red_zone_arg1;
+	unsigned long a2 = usdt_red_zone_arg2;
+	unsigned long a3 = usdt_red_zone_arg3;
+
+	USDT(optimized_attach, usdt_red_zone, a1, a2, a3);
+}
+
 #endif