6.13-stable review patch. If anyone has any objections, please let me know.
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From: Masami Hiramatsu (Google) mhiramat@kernel.org
[ Upstream commit d5d01b71996ec03af51b3c0736c92d0fc89703b5 ]
Add ftrace_fill_perf_regs() which should be compatible with the perf_fetch_caller_regs(). In other words, the pt_regs returned from the ftrace_fill_perf_regs() must satisfy 'user_mode(regs) == false' and can be used for stack tracing.
Signed-off-by: Masami Hiramatsu (Google) mhiramat@kernel.org Acked-by: Will Deacon will@kernel.org Acked-by: Heiko Carstens hca@linux.ibm.com # s390 Cc: Alexei Starovoitov alexei.starovoitov@gmail.com Cc: Florent Revest revest@chromium.org Cc: Martin KaFai Lau martin.lau@linux.dev Cc: bpf bpf@vger.kernel.org Cc: Alexei Starovoitov ast@kernel.org Cc: Jiri Olsa jolsa@kernel.org Cc: Alan Maguire alan.maguire@oracle.com Cc: Heiko Carstens hca@linux.ibm.com Cc: Mark Rutland mark.rutland@arm.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Cc: Michael Ellerman mpe@ellerman.id.au Cc: Nicholas Piggin npiggin@gmail.com Cc: Christophe Leroy christophe.leroy@csgroup.eu Cc: Naveen N Rao naveen@kernel.org Cc: Madhavan Srinivasan maddy@linux.ibm.com Cc: Vasily Gorbik gor@linux.ibm.com Cc: Alexander Gordeev agordeev@linux.ibm.com Cc: Christian Borntraeger borntraeger@linux.ibm.com Cc: Sven Schnelle svens@linux.ibm.com Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: Borislav Petkov bp@alien8.de Cc: Dave Hansen dave.hansen@linux.intel.com Cc: x86@kernel.org Cc: "H. Peter Anvin" hpa@zytor.com Link: https://lore.kernel.org/173518997908.391279.15910334347345106424.stgit@devno... Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Stable-dep-of: db5e228611b1 ("tracing: fprobe-events: Log error for exceeding the number of entry args") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/include/asm/ftrace.h | 7 +++++++ arch/powerpc/include/asm/ftrace.h | 7 +++++++ arch/s390/include/asm/ftrace.h | 6 ++++++ arch/x86/include/asm/ftrace.h | 7 +++++++ include/linux/ftrace.h | 31 +++++++++++++++++++++++++++++++ 5 files changed, 58 insertions(+)
diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 09210f853f12d..10e56522122aa 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -148,6 +148,13 @@ ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) return regs; }
+#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->pc = arch_ftrace_regs(fregs)->pc; \ + (_regs)->regs[29] = arch_ftrace_regs(fregs)->fp; \ + (_regs)->sp = arch_ftrace_regs(fregs)->sp; \ + (_regs)->pstate = PSR_MODE_EL1h; \ + } while (0) + int ftrace_regs_query_register_offset(const char *name);
int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index db481b336bca4..fe181bafdca4f 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -43,6 +43,13 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs * return arch_ftrace_regs(fregs)->regs.msr ? &arch_ftrace_regs(fregs)->regs : NULL; }
+#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->result = 0; \ + (_regs)->nip = arch_ftrace_regs(fregs)->regs.nip; \ + (_regs)->gpr[1] = arch_ftrace_regs(fregs)->regs.gpr[1]; \ + asm volatile("mfmsr %0" : "=r" ((_regs)->msr)); \ + } while (0) + static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 5c94c1fc1bc1c..5b7cb49c41ee0 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -76,6 +76,12 @@ ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) return ftrace_regs_get_stack_pointer(fregs); }
+#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->psw.mask = 0; \ + (_regs)->psw.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \ + (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \ + } while (0) + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS /* * When an ftrace registered caller is tracing a function that is diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index d61407c680c28..7e06f8c7937aa 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -47,6 +47,13 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) return &arch_ftrace_regs(fregs)->regs; }
+#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; \ + (_regs)->cs = __KERNEL_CS; \ + (_regs)->flags = 0; \ + } while (0) + #define ftrace_regs_set_instruction_pointer(fregs, _ip) \ do { arch_ftrace_regs(fregs)->regs.ip = (_ip); } while (0)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 863c014dff683..56cb3d243c6c4 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -207,6 +207,37 @@ ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs)
#endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS */
+#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS + +/* + * Please define arch dependent pt_regs which compatible to the + * perf_arch_fetch_caller_regs() but based on ftrace_regs. + * This requires + * - user_mode(_regs) returns false (always kernel mode). + * - able to use the _regs for stack trace. + */ +#ifndef arch_ftrace_fill_perf_regs +/* As same as perf_arch_fetch_caller_regs(), do nothing by default */ +#define arch_ftrace_fill_perf_regs(fregs, _regs) do {} while (0) +#endif + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + arch_ftrace_fill_perf_regs(fregs, regs); + return regs; +} + +#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + return &arch_ftrace_regs(fregs)->regs; +} + +#endif + /* * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs. * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs.