diff options
| -rw-r--r-- | arch/x86/events/core.c | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/ftrace.h | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace_64.S | 8 | ||||
| -rw-r--r-- | include/linux/ftrace.h | 10 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c | 150 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/stacktrace_ips.c | 49 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/test_kmods/bpf_testmod.c | 26 |
7 files changed, 251 insertions, 7 deletions
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 745caa6c15a3..fa6c47b50989 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2789,13 +2789,13 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re return; } - if (perf_callchain_store(entry, regs->ip)) - return; - - if (perf_hw_regs(regs)) + if (perf_hw_regs(regs)) { + if (perf_callchain_store(entry, regs->ip)) + return; unwind_start(&state, current, regs, NULL); - else + } else { unwind_start(&state, current, NULL, (void *)regs->sp); + } for (; !unwind_done(&state); unwind_next_frame(&state)) { addr = unwind_get_return_address(&state); diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 93156ac4ffe0..b08c95872eed 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -56,6 +56,11 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) return &arch_ftrace_regs(fregs)->regs; } +#define arch_ftrace_partial_regs(regs) do { \ + regs->flags &= ~X86_EFLAGS_FIXED; \ + regs->cs = __KERNEL_CS; \ +} while (0) + #define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ (_regs)->ip = arch_ftrace_regs(fregs)->regs.ip; \ (_regs)->sp = arch_ftrace_regs(fregs)->regs.sp; \ diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 367da3638167..823dbdd0eb41 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -354,12 +354,17 @@ SYM_CODE_START(return_to_handler) UNWIND_HINT_UNDEFINED ANNOTATE_NOENDBR + /* Restore return_to_handler value that got eaten by previous ret instruction. */ + subq $8, %rsp + UNWIND_HINT_FUNC + /* Save ftrace_regs for function exit context */ subq $(FRAME_SIZE), %rsp movq %rax, RAX(%rsp) movq %rdx, RDX(%rsp) movq %rbp, RBP(%rsp) + movq %rsp, RSP(%rsp) movq %rsp, %rdi call ftrace_return_to_handler @@ -368,7 +373,8 @@ SYM_CODE_START(return_to_handler) movq RDX(%rsp), %rdx movq RAX(%rsp), %rax - addq $(FRAME_SIZE), %rsp + addq $(FRAME_SIZE) + 8, %rsp + /* * Jump back to the old return address. This cannot be JMP_NOSPEC rdi * since IBT would demand that contain ENDBR, which simply isn't so for diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 7ded7df6e9b5..07f8c309e432 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -193,6 +193,10 @@ static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs #if !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) || \ defined(CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS) +#ifndef arch_ftrace_partial_regs +#define arch_ftrace_partial_regs(regs) do {} while (0) +#endif + static __always_inline struct pt_regs * ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) { @@ -202,7 +206,11 @@ ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) * Since arch_ftrace_get_regs() will check some members and may return * NULL, we can not use it. */ - return &arch_ftrace_regs(fregs)->regs; + regs = &arch_ftrace_regs(fregs)->regs; + + /* Allow arch specific updates to regs. */ + arch_ftrace_partial_regs(regs); + return regs; } #endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS */ diff --git a/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c b/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c new file mode 100644 index 000000000000..c9efdd2a5b18 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_ips.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include "stacktrace_ips.skel.h" + +#ifdef __x86_64__ +static int check_stacktrace_ips(int fd, __u32 key, int cnt, ...) +{ + __u64 ips[PERF_MAX_STACK_DEPTH]; + struct ksyms *ksyms = NULL; + int i, err = 0; + va_list args; + + /* sorted by addr */ + ksyms = load_kallsyms_local(); + if (!ASSERT_OK_PTR(ksyms, "load_kallsyms_local")) + return -1; + + /* unlikely, but... */ + if (!ASSERT_LT(cnt, PERF_MAX_STACK_DEPTH, "check_max")) + return -1; + + err = bpf_map_lookup_elem(fd, &key, ips); + if (err) + goto out; + + /* + * Compare all symbols provided via arguments with stacktrace ips, + * and their related symbol addresses.t + */ + va_start(args, cnt); + + for (i = 0; i < cnt; i++) { + unsigned long val; + struct ksym *ksym; + + val = va_arg(args, unsigned long); + ksym = ksym_search_local(ksyms, ips[i]); + if (!ASSERT_OK_PTR(ksym, "ksym_search_local")) + break; + ASSERT_EQ(ksym->addr, val, "stack_cmp"); + } + + va_end(args); + +out: + free_kallsyms_local(ksyms); + return err; +} + +static void test_stacktrace_ips_kprobe_multi(bool retprobe) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts, + .retprobe = retprobe + ); + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct stacktrace_ips *skel; + + skel = stacktrace_ips__open_and_load(); + if (!ASSERT_OK_PTR(skel, "stacktrace_ips__open_and_load")) + return; + + if (!skel->kconfig->CONFIG_UNWINDER_ORC) { + test__skip(); + goto cleanup; + } + + skel->links.kprobe_multi_test = bpf_program__attach_kprobe_multi_opts( + skel->progs.kprobe_multi_test, + "bpf_testmod_stacktrace_test", &opts); + if (!ASSERT_OK_PTR(skel->links.kprobe_multi_test, "bpf_program__attach_kprobe_multi_opts")) + goto cleanup; + + trigger_module_test_read(1); + + load_kallsyms(); + + check_stacktrace_ips(bpf_map__fd(skel->maps.stackmap), skel->bss->stack_key, 4, + ksym_get_addr("bpf_testmod_stacktrace_test_3"), + ksym_get_addr("bpf_testmod_stacktrace_test_2"), + ksym_get_addr("bpf_testmod_stacktrace_test_1"), + ksym_get_addr("bpf_testmod_test_read")); + +cleanup: + stacktrace_ips__destroy(skel); +} + +static void test_stacktrace_ips_raw_tp(void) +{ + __u32 info_len = sizeof(struct bpf_prog_info); + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct bpf_prog_info info = {}; + struct stacktrace_ips *skel; + __u64 bpf_prog_ksym = 0; + int err; + + skel = stacktrace_ips__open_and_load(); + if (!ASSERT_OK_PTR(skel, "stacktrace_ips__open_and_load")) + return; + + if (!skel->kconfig->CONFIG_UNWINDER_ORC) { + test__skip(); + goto cleanup; + } + + skel->links.rawtp_test = bpf_program__attach_raw_tracepoint( + skel->progs.rawtp_test, + "bpf_testmod_test_read"); + if (!ASSERT_OK_PTR(skel->links.rawtp_test, "bpf_program__attach_raw_tracepoint")) + goto cleanup; + + /* get bpf program address */ + info.jited_ksyms = ptr_to_u64(&bpf_prog_ksym); + info.nr_jited_ksyms = 1; + err = bpf_prog_get_info_by_fd(bpf_program__fd(skel->progs.rawtp_test), + &info, &info_len); + if (!ASSERT_OK(err, "bpf_prog_get_info_by_fd")) + goto cleanup; + + trigger_module_test_read(1); + + load_kallsyms(); + + check_stacktrace_ips(bpf_map__fd(skel->maps.stackmap), skel->bss->stack_key, 2, + bpf_prog_ksym, + ksym_get_addr("bpf_trace_run2")); + +cleanup: + stacktrace_ips__destroy(skel); +} + +static void __test_stacktrace_ips(void) +{ + if (test__start_subtest("kprobe_multi")) + test_stacktrace_ips_kprobe_multi(false); + if (test__start_subtest("kretprobe_multi")) + test_stacktrace_ips_kprobe_multi(true); + if (test__start_subtest("raw_tp")) + test_stacktrace_ips_raw_tp(); +} +#else +static void __test_stacktrace_ips(void) +{ + test__skip(); +} +#endif + +void test_stacktrace_ips(void) +{ + __test_stacktrace_ips(); +} diff --git a/tools/testing/selftests/bpf/progs/stacktrace_ips.c b/tools/testing/selftests/bpf/progs/stacktrace_ips.c new file mode 100644 index 000000000000..a96c8150d7f5 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/stacktrace_ips.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2018 Facebook + +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +#ifndef PERF_MAX_STACK_DEPTH +#define PERF_MAX_STACK_DEPTH 127 +#endif + +typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH]; + +struct { + __uint(type, BPF_MAP_TYPE_STACK_TRACE); + __uint(max_entries, 16384); + __type(key, __u32); + __type(value, stack_trace_t); +} stackmap SEC(".maps"); + +extern bool CONFIG_UNWINDER_ORC __kconfig __weak; + +/* + * This function is here to have CONFIG_UNWINDER_ORC + * used and added to object BTF. + */ +int unused(void) +{ + return CONFIG_UNWINDER_ORC ? 0 : 1; +} + +__u32 stack_key; + +SEC("kprobe.multi") +int kprobe_multi_test(struct pt_regs *ctx) +{ + stack_key = bpf_get_stackid(ctx, &stackmap, 0); + return 0; +} + +SEC("raw_tp/bpf_testmod_test_read") +int rawtp_test(void *ctx) +{ + /* Skip ebpf program entry in the stack. */ + stack_key = bpf_get_stackid(ctx, &stackmap, 0); + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c index 8074bc5f6f20..ed0a4721d8fd 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c @@ -417,6 +417,30 @@ noinline int bpf_testmod_fentry_test11(u64 a, void *b, short c, int d, return a + (long)b + c + d + (long)e + f + g + h + i + j + k; } +noinline void bpf_testmod_stacktrace_test(void) +{ + /* used for stacktrace test as attach function */ + asm volatile (""); +} + +noinline void bpf_testmod_stacktrace_test_3(void) +{ + bpf_testmod_stacktrace_test(); + asm volatile (""); +} + +noinline void bpf_testmod_stacktrace_test_2(void) +{ + bpf_testmod_stacktrace_test_3(); + asm volatile (""); +} + +noinline void bpf_testmod_stacktrace_test_1(void) +{ + bpf_testmod_stacktrace_test_2(); + asm volatile (""); +} + int bpf_testmod_fentry_ok; noinline ssize_t @@ -497,6 +521,8 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, 21, 22, 23, 24, 25, 26) != 231) goto out; + bpf_testmod_stacktrace_test_1(); + bpf_testmod_fentry_ok = 1; out: return -EIO; /* always fail */ |