* [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 [not found] <CAA93ih1-xpm1P0suT6SNCc_ARvAfyBEwb0-uKFikM5k4CvG8jg@mail.gmail.com> @ 2018-11-27 16:29 ` Masami Hiramatsu 2018-11-27 16:32 ` Steven Rostedt 2018-11-27 16:58 ` Will Deacon 0 siblings, 2 replies; 12+ messages in thread From: Masami Hiramatsu @ 2018-11-27 16:29 UTC (permalink / raw) To: Steven Rostedt, Catalin Marinas Cc: Naresh Kamboju, Will Deacon, Mark Rutland, Ingo Molnar, Masami Hiramatsu, Masami Hiramatsu, linux-kernel, stable Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") introduced "__arm64_" prefix to all syscall wrapper symbols in sys_call_table, syscall tracer can not find corresponding metadata from syscall name. In the result, we have no syscall ftrace events on arm64 kernel, and some bpf testcases are failed on arm64. To fix this issue, this introduces custom arch_syscall_match_sym_name() which skips first 8 bytes when comparing the syscall and symbol names. Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org --- arch/arm64/include/asm/ftrace.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index caa955f10e19..a710f79db442 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -56,6 +56,15 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) { return is_compat_task(); } + +#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME + +static inline bool arch_syscall_match_sym_name(const char *sym, + const char *name) +{ + /* Since all syscall functions have __arm64_ prefix, we must skip it */ + return !strcmp(sym + 8, name); +} #endif /* ifndef __ASSEMBLY__ */ #endif /* __ASM_FTRACE_H */ ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-27 16:29 ` [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 Masami Hiramatsu @ 2018-11-27 16:32 ` Steven Rostedt 2018-11-27 16:58 ` Will Deacon 1 sibling, 0 replies; 12+ messages in thread From: Steven Rostedt @ 2018-11-27 16:32 UTC (permalink / raw) To: Masami Hiramatsu Cc: Catalin Marinas, Naresh Kamboju, Will Deacon, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable On Wed, 28 Nov 2018 01:29:45 +0900 Masami Hiramatsu <mhiramat@kernel.org> wrote: > Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") > introduced "__arm64_" prefix to all syscall wrapper symbols in > sys_call_table, syscall tracer can not find corresponding > metadata from syscall name. In the result, we have no syscall > ftrace events on arm64 kernel, and some bpf testcases are failed > on arm64. > > To fix this issue, this introduces custom > arch_syscall_match_sym_name() which skips first 8 bytes when > comparing the syscall and symbol names. > Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> -- Steve > Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") > Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > Cc: stable@vger.kernel.org > --- > arch/arm64/include/asm/ftrace.h | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index caa955f10e19..a710f79db442 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -56,6 +56,15 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) > { > return is_compat_task(); > } > + > +#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME > + > +static inline bool arch_syscall_match_sym_name(const char *sym, > + const char *name) > +{ > + /* Since all syscall functions have __arm64_ prefix, we must skip it */ > + return !strcmp(sym + 8, name); > +} > #endif /* ifndef __ASSEMBLY__ */ > > #endif /* __ASM_FTRACE_H */ ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-27 16:29 ` [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 Masami Hiramatsu 2018-11-27 16:32 ` Steven Rostedt @ 2018-11-27 16:58 ` Will Deacon 2018-11-27 18:18 ` Steven Rostedt 1 sibling, 1 reply; 12+ messages in thread From: Will Deacon @ 2018-11-27 16:58 UTC (permalink / raw) To: Masami Hiramatsu Cc: Steven Rostedt, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable Hi Masami, On Wed, Nov 28, 2018 at 01:29:45AM +0900, Masami Hiramatsu wrote: > Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") > introduced "__arm64_" prefix to all syscall wrapper symbols in > sys_call_table, syscall tracer can not find corresponding > metadata from syscall name. In the result, we have no syscall > ftrace events on arm64 kernel, and some bpf testcases are failed > on arm64. > > To fix this issue, this introduces custom > arch_syscall_match_sym_name() which skips first 8 bytes when > comparing the syscall and symbol names. > > Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") > Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > Cc: stable@vger.kernel.org > --- > arch/arm64/include/asm/ftrace.h | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index caa955f10e19..a710f79db442 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -56,6 +56,15 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) > { > return is_compat_task(); > } > + > +#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME > + > +static inline bool arch_syscall_match_sym_name(const char *sym, > + const char *name) > +{ > + /* Since all syscall functions have __arm64_ prefix, we must skip it */ > + return !strcmp(sym + 8, name); > +} This looks fine to me, but I'm curious about whether this is supposed to work with compat syscalls as well, where the prefix is "__arm64_compat_". If we broadly follow the x86 lead, we'd have: return (!strncmp(sym, "__arm64_", 8) && !strcmp(sym + 8, name)) || (!strncmp(sym, "__arm64_compat_", 15) && !strcmp(sym + 15, name)); Do we need to handle compat (i.e. 32-bit) tasks here? Will ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-27 16:58 ` Will Deacon @ 2018-11-27 18:18 ` Steven Rostedt 2018-11-27 23:55 ` Masami Hiramatsu 0 siblings, 1 reply; 12+ messages in thread From: Steven Rostedt @ 2018-11-27 18:18 UTC (permalink / raw) To: Will Deacon Cc: Masami Hiramatsu, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable On Tue, 27 Nov 2018 16:58:49 +0000 Will Deacon <will.deacon@arm.com> wrote: > This looks fine to me, but I'm curious about whether this is supposed to > work with compat syscalls as well, where the prefix is "__arm64_compat_". > > If we broadly follow the x86 lead, we'd have: > > return (!strncmp(sym, "__arm64_", 8) && !strcmp(sym + 8, name)) || > (!strncmp(sym, "__arm64_compat_", 15) && !strcmp(sym + 15, name)); > > Do we need to handle compat (i.e. 32-bit) tasks here? Only if you want to trace compat syscalls as well ;-) -- Steve ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-27 18:18 ` Steven Rostedt @ 2018-11-27 23:55 ` Masami Hiramatsu 2018-11-28 12:05 ` Will Deacon 0 siblings, 1 reply; 12+ messages in thread From: Masami Hiramatsu @ 2018-11-27 23:55 UTC (permalink / raw) To: Steven Rostedt Cc: Will Deacon, Masami Hiramatsu, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable, AKASHI Takahiro Hi Will, On Tue, 27 Nov 2018 13:18:59 -0500 Steven Rostedt <rostedt@goodmis.org> wrote: > On Tue, 27 Nov 2018 16:58:49 +0000 > Will Deacon <will.deacon@arm.com> wrote: > > > This looks fine to me, but I'm curious about whether this is supposed to > > work with compat syscalls as well, where the prefix is "__arm64_compat_". > > > > If we broadly follow the x86 lead, we'd have: > > > > return (!strncmp(sym, "__arm64_", 8) && !strcmp(sym + 8, name)) || > > (!strncmp(sym, "__arm64_compat_", 15) && !strcmp(sym + 15, name)); > > > > Do we need to handle compat (i.e. 32-bit) tasks here? > > Only if you want to trace compat syscalls as well ;-) Actually I thought about that, but I found below comment in arch/arm64/include/asm/ftrace.h * Because AArch32 mode does not share the same syscall table with AArch64, * tracing compat syscalls may result in reporting bogus syscalls or even * hang-up, so just do not trace them. That's why I dropped compat syscall support. Thank you, -- Masami Hiramatsu <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-27 23:55 ` Masami Hiramatsu @ 2018-11-28 12:05 ` Will Deacon 2018-11-28 14:22 ` Steven Rostedt 0 siblings, 1 reply; 12+ messages in thread From: Will Deacon @ 2018-11-28 12:05 UTC (permalink / raw) To: Masami Hiramatsu Cc: Steven Rostedt, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable, AKASHI Takahiro Hi Masami, On Wed, Nov 28, 2018 at 08:55:55AM +0900, Masami Hiramatsu wrote: > On Tue, 27 Nov 2018 13:18:59 -0500 > Steven Rostedt <rostedt@goodmis.org> wrote: > > > On Tue, 27 Nov 2018 16:58:49 +0000 > > Will Deacon <will.deacon@arm.com> wrote: > > > > > This looks fine to me, but I'm curious about whether this is supposed to > > > work with compat syscalls as well, where the prefix is "__arm64_compat_". > > > > > > If we broadly follow the x86 lead, we'd have: > > > > > > return (!strncmp(sym, "__arm64_", 8) && !strcmp(sym + 8, name)) || > > > (!strncmp(sym, "__arm64_compat_", 15) && !strcmp(sym + 15, name)); > > > > > > Do we need to handle compat (i.e. 32-bit) tasks here? > > > > Only if you want to trace compat syscalls as well ;-) > > Actually I thought about that, but I found below comment in > arch/arm64/include/asm/ftrace.h > > * Because AArch32 mode does not share the same syscall table with AArch64, > * tracing compat syscalls may result in reporting bogus syscalls or even > * hang-up, so just do not trace them. > > That's why I dropped compat syscall support. Ok! Then please add a comment to arch_syscall_match_sym_name() along those lines, and you can add my ack: Acked-by: Will Deacon <will.deacon@arm.com> Thanks, Will ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-28 12:05 ` Will Deacon @ 2018-11-28 14:22 ` Steven Rostedt 2018-11-28 19:59 ` Will Deacon 0 siblings, 1 reply; 12+ messages in thread From: Steven Rostedt @ 2018-11-28 14:22 UTC (permalink / raw) To: Will Deacon Cc: Masami Hiramatsu, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable, AKASHI Takahiro On Wed, 28 Nov 2018 12:05:02 +0000 Will Deacon <will.deacon@arm.com> wrote: > Ok! Then please add a comment to arch_syscall_match_sym_name() along those > lines, and you can add my ack: > > Acked-by: Will Deacon <will.deacon@arm.com> Shouldn't this go through your tree? -- Steve ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-28 14:22 ` Steven Rostedt @ 2018-11-28 19:59 ` Will Deacon 2018-11-29 5:38 ` Masami Hiramatsu 2018-11-29 5:39 ` [PATCH v2] " Masami Hiramatsu 0 siblings, 2 replies; 12+ messages in thread From: Will Deacon @ 2018-11-28 19:59 UTC (permalink / raw) To: Steven Rostedt Cc: Masami Hiramatsu, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable, AKASHI Takahiro On Wed, Nov 28, 2018 at 09:22:23AM -0500, Steven Rostedt wrote: > On Wed, 28 Nov 2018 12:05:02 +0000 > Will Deacon <will.deacon@arm.com> wrote: > > > Ok! Then please add a comment to arch_syscall_match_sym_name() along those > > lines, and you can add my ack: > > > > Acked-by: Will Deacon <will.deacon@arm.com> > > Shouldn't this go through your tree? Yup; I'm hoping Catalin will pick it up as a fix for 4.20 (we take it in turns, so I'm looking at stuff for 4.21 atm). Will ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-28 19:59 ` Will Deacon @ 2018-11-29 5:38 ` Masami Hiramatsu 2018-11-29 5:39 ` [PATCH v2] " Masami Hiramatsu 1 sibling, 0 replies; 12+ messages in thread From: Masami Hiramatsu @ 2018-11-29 5:38 UTC (permalink / raw) To: Will Deacon Cc: Steven Rostedt, Masami Hiramatsu, Catalin Marinas, Naresh Kamboju, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable, AKASHI Takahiro On Wed, 28 Nov 2018 19:59:22 +0000 Will Deacon <will.deacon@arm.com> wrote: > On Wed, Nov 28, 2018 at 09:22:23AM -0500, Steven Rostedt wrote: > > On Wed, 28 Nov 2018 12:05:02 +0000 > > Will Deacon <will.deacon@arm.com> wrote: > > > > > Ok! Then please add a comment to arch_syscall_match_sym_name() along those > > > lines, and you can add my ack: > > > > > > Acked-by: Will Deacon <will.deacon@arm.com> > > > > Shouldn't this go through your tree? > > Yup; I'm hoping Catalin will pick it up as a fix for 4.20 (we take it in > turns, so I'm looking at stuff for 4.21 atm). OK, I'll add a comment about compat syscalls. BTW, this should be applied to 4.19 too, since without this, no one can use syscall events on arm64. Thank you, -- Masami Hiramatsu <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v2] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-28 19:59 ` Will Deacon 2018-11-29 5:38 ` Masami Hiramatsu @ 2018-11-29 5:39 ` Masami Hiramatsu 2018-11-29 16:53 ` Catalin Marinas 1 sibling, 1 reply; 12+ messages in thread From: Masami Hiramatsu @ 2018-11-29 5:39 UTC (permalink / raw) To: Catalin Marinas Cc: Steven Rostedt, Naresh Kamboju, Will Deacon, Mark Rutland, Ingo Molnar, Masami Hiramatsu, Masami Hiramatsu, linux-kernel, stable Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") introduced "__arm64_" prefix to all syscall wrapper symbols in sys_call_table, syscall tracer can not find corresponding metadata from syscall name. In the result, we have no syscall ftrace events on arm64 kernel, and some bpf testcases are failed on arm64. To fix this issue, this introduces custom arch_syscall_match_sym_name() which skips first 8 bytes when comparing the syscall and symbol names. Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: stable@vger.kernel.org --- arch/arm64/include/asm/ftrace.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index caa955f10e19..fac54fb050d0 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -56,6 +56,19 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) { return is_compat_task(); } + +#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME + +static inline bool arch_syscall_match_sym_name(const char *sym, + const char *name) +{ + /* + * Since all syscall functions have __arm64_ prefix, we must skip it. + * However, as we described above, we decided to ignore compat + * syscalls, so we don't care about __arm64_compat_ prefix here. + */ + return !strcmp(sym + 8, name); +} #endif /* ifndef __ASSEMBLY__ */ #endif /* __ASM_FTRACE_H */ ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v2] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-29 5:39 ` [PATCH v2] " Masami Hiramatsu @ 2018-11-29 16:53 ` Catalin Marinas 2018-11-29 22:13 ` Masami Hiramatsu 0 siblings, 1 reply; 12+ messages in thread From: Catalin Marinas @ 2018-11-29 16:53 UTC (permalink / raw) To: Masami Hiramatsu Cc: Steven Rostedt, Naresh Kamboju, Will Deacon, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable On Thu, Nov 29, 2018 at 02:39:33PM +0900, Masami Hiramatsu wrote: > Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") > introduced "__arm64_" prefix to all syscall wrapper symbols in > sys_call_table, syscall tracer can not find corresponding > metadata from syscall name. In the result, we have no syscall > ftrace events on arm64 kernel, and some bpf testcases are failed > on arm64. > > To fix this issue, this introduces custom > arch_syscall_match_sym_name() which skips first 8 bytes when > comparing the syscall and symbol names. > > Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") > Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > Acked-by: Will Deacon <will.deacon@arm.com> > Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> > Cc: stable@vger.kernel.org Queued for 4.20. Thanks. -- Catalin ^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v2] arm64: ftrace: Fix to enable syscall events on arm64 2018-11-29 16:53 ` Catalin Marinas @ 2018-11-29 22:13 ` Masami Hiramatsu 0 siblings, 0 replies; 12+ messages in thread From: Masami Hiramatsu @ 2018-11-29 22:13 UTC (permalink / raw) To: Catalin Marinas Cc: Steven Rostedt, Naresh Kamboju, Will Deacon, Mark Rutland, Ingo Molnar, Masami Hiramatsu, linux-kernel, stable On Thu, 29 Nov 2018 16:53:30 +0000 Catalin Marinas <catalin.marinas@arm.com> wrote: > On Thu, Nov 29, 2018 at 02:39:33PM +0900, Masami Hiramatsu wrote: > > Since commit 4378a7d4be30 ("arm64: implement syscall wrappers") > > introduced "__arm64_" prefix to all syscall wrapper symbols in > > sys_call_table, syscall tracer can not find corresponding > > metadata from syscall name. In the result, we have no syscall > > ftrace events on arm64 kernel, and some bpf testcases are failed > > on arm64. > > > > To fix this issue, this introduces custom > > arch_syscall_match_sym_name() which skips first 8 bytes when > > comparing the syscall and symbol names. > > > > Fixes: 4378a7d4be30 ("arm64: implement syscall wrappers") > > Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> > > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > > Acked-by: Will Deacon <will.deacon@arm.com> > > Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> > > Cc: stable@vger.kernel.org > > Queued for 4.20. Thanks. Thank you Catalin! > > -- > Catalin -- Masami Hiramatsu <mhiramat@kernel.org> ^ permalink raw reply [flat|nested] 12+ messages in thread
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[not found] <CAA93ih1-xpm1P0suT6SNCc_ARvAfyBEwb0-uKFikM5k4CvG8jg@mail.gmail.com>
2018-11-27 16:29 ` [PATCH] arm64: ftrace: Fix to enable syscall events on arm64 Masami Hiramatsu
2018-11-27 16:32 ` Steven Rostedt
2018-11-27 16:58 ` Will Deacon
2018-11-27 18:18 ` Steven Rostedt
2018-11-27 23:55 ` Masami Hiramatsu
2018-11-28 12:05 ` Will Deacon
2018-11-28 14:22 ` Steven Rostedt
2018-11-28 19:59 ` Will Deacon
2018-11-29 5:38 ` Masami Hiramatsu
2018-11-29 5:39 ` [PATCH v2] " Masami Hiramatsu
2018-11-29 16:53 ` Catalin Marinas
2018-11-29 22:13 ` Masami Hiramatsu
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