Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[patchwork-bot+linux-riscv]

Hello:

This patch was applied to riscv/linux.git (fixes)
by Palmer Dabbelt :

On Tue,  3 Oct 2023 20:24:07 +0200 you wrote:
> ftrace creates entries for each syscall in the tracefs but has failed
> since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
> prefixes all riscv syscalls with __riscv_.
> 
> So fix this by implementing arch_syscall_match_sym_name() which allows us
> to ignore this prefix.
> 
> [...]

Here is the summary with links:
  - [-fixes] riscv: Fix ftrace syscall handling which are now prefixed with 
__riscv_
https://git.kernel.org/riscv/c/a87e7d3e8832

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Björn Töpel]

Alexandre Ghiti  writes:

> ftrace creates entries for each syscall in the tracefs but has failed
> since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
> prefixes all riscv syscalls with __riscv_.
>
> So fix this by implementing arch_syscall_match_sym_name() which allows us
> to ignore this prefix.
>
> And also ignore compat syscalls like x86/arm64 by implementing
> arch_trace_is_compat_syscall().
>
> Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
> Signed-off-by: Alexandre Ghiti 

This fix does the BPF test suite happier!

Tested-by: Björn Töpel 

Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Björn Töpel]

Alexandre Ghiti  writes:

> @Conor Dooley This fails checkpatch but the documentation here states
> that this is how to do:
> https://elixir.bootlin.com/linux/latest/source/Documentation/trace/ftrace-design.rst#L246

FWIW, I'll relax the PW CI checkpatch test going forward. It's way too
strict...

Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Google]

On Tue,  3 Oct 2023 20:24:07 +0200
Alexandre Ghiti  wrote:

> ftrace creates entries for each syscall in the tracefs but has failed
> since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
> prefixes all riscv syscalls with __riscv_.
> 
> So fix this by implementing arch_syscall_match_sym_name() which allows us
> to ignore this prefix.
> 
> And also ignore compat syscalls like x86/arm64 by implementing
> arch_trace_is_compat_syscall().
> 

Looks good to me,

Acked-by: Masami Hiramatsu (Google) 

Thank you,

> Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
> Signed-off-by: Alexandre Ghiti 
> ---
>  arch/riscv/include/asm/ftrace.h | 21 +
>  1 file changed, 21 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
> index 740a979171e5..2b2f5df7ef2c 100644
> --- a/arch/riscv/include/asm/ftrace.h
> +++ b/arch/riscv/include/asm/ftrace.h
> @@ -31,6 +31,27 @@ static inline unsigned long ftrace_call_adjust(unsigned 
> long addr)
>   return addr;
>  }
>  
> +/*
> + * Let's do like x86/arm64 and ignore the compat syscalls.
> + */
> +#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
> +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 __riscv_ prefix, we must skip it.
> +  * However, as we described above, we decided to ignore compat
> +  * syscalls, so we don't care about __riscv_compat_ prefix here.
> +  */
> + return !strcmp(sym + 8, name);
> +}
> +
>  struct dyn_arch_ftrace {
>  };
>  #endif
> -- 
> 2.39.2
> 


-- 
Masami Hiramatsu (Google) 

Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Sami Tolvanen]

On Tue, Oct 3, 2023 at 11:24 AM Alexandre Ghiti  wrote:
>
> ftrace creates entries for each syscall in the tracefs but has failed
> since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
> prefixes all riscv syscalls with __riscv_.
>
> So fix this by implementing arch_syscall_match_sym_name() which allows us
> to ignore this prefix.
>
> And also ignore compat syscalls like x86/arm64 by implementing
> arch_trace_is_compat_syscall().
>
> Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
> Signed-off-by: Alexandre Ghiti 
> ---
>  arch/riscv/include/asm/ftrace.h | 21 +
>  1 file changed, 21 insertions(+)
>
> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
> index 740a979171e5..2b2f5df7ef2c 100644
> --- a/arch/riscv/include/asm/ftrace.h
> +++ b/arch/riscv/include/asm/ftrace.h
> @@ -31,6 +31,27 @@ static inline unsigned long ftrace_call_adjust(unsigned 
> long addr)
> return addr;
>  }
>
> +/*
> + * Let's do like x86/arm64 and ignore the compat syscalls.
> + */
> +#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
> +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 __riscv_ prefix, we must skip it.
> +* However, as we described above, we decided to ignore compat
> +* syscalls, so we don't care about __riscv_compat_ prefix here.
> +*/
> +   return !strcmp(sym + 8, name);
> +}

Good catch, thanks for fixing this!

Reviewed-by: Sami Tolvanen 

Sami

Re: [PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Alexandre Ghiti]

@Conor Dooley This fails checkpatch but the documentation here states
that this is how to do:
https://elixir.bootlin.com/linux/latest/source/Documentation/trace/ftrace-design.rst#L246

On Tue, Oct 3, 2023 at 8:24 PM Alexandre Ghiti  wrote:
>
> ftrace creates entries for each syscall in the tracefs but has failed
> since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
> prefixes all riscv syscalls with __riscv_.
>
> So fix this by implementing arch_syscall_match_sym_name() which allows us
> to ignore this prefix.
>
> And also ignore compat syscalls like x86/arm64 by implementing
> arch_trace_is_compat_syscall().
>
> Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
> Signed-off-by: Alexandre Ghiti 
> ---
>  arch/riscv/include/asm/ftrace.h | 21 +
>  1 file changed, 21 insertions(+)
>
> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
> index 740a979171e5..2b2f5df7ef2c 100644
> --- a/arch/riscv/include/asm/ftrace.h
> +++ b/arch/riscv/include/asm/ftrace.h
> @@ -31,6 +31,27 @@ static inline unsigned long ftrace_call_adjust(unsigned 
> long addr)
> return addr;
>  }
>
> +/*
> + * Let's do like x86/arm64 and ignore the compat syscalls.
> + */
> +#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
> +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 __riscv_ prefix, we must skip it.
> +* However, as we described above, we decided to ignore compat
> +* syscalls, so we don't care about __riscv_compat_ prefix here.
> +*/
> +   return !strcmp(sym + 8, name);
> +}
> +
>  struct dyn_arch_ftrace {
>  };
>  #endif
> --
> 2.39.2
>

[PATCH -fixes] riscv: Fix ftrace syscall handling which are now prefixed with __riscv_

[Alexandre Ghiti]

ftrace creates entries for each syscall in the tracefs but has failed
since commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") which
prefixes all riscv syscalls with __riscv_.

So fix this by implementing arch_syscall_match_sym_name() which allows us
to ignore this prefix.

And also ignore compat syscalls like x86/arm64 by implementing
arch_trace_is_compat_syscall().

Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
Signed-off-by: Alexandre Ghiti 
---
 arch/riscv/include/asm/ftrace.h | 21 +
 1 file changed, 21 insertions(+)

diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
index 740a979171e5..2b2f5df7ef2c 100644
--- a/arch/riscv/include/asm/ftrace.h
+++ b/arch/riscv/include/asm/ftrace.h
@@ -31,6 +31,27 @@ static inline unsigned long ftrace_call_adjust(unsigned long 
addr)
return addr;
 }
 
+/*
+ * Let's do like x86/arm64 and ignore the compat syscalls.
+ */
+#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
+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 __riscv_ prefix, we must skip it.
+* However, as we described above, we decided to ignore compat
+* syscalls, so we don't care about __riscv_compat_ prefix here.
+*/
+   return !strcmp(sym + 8, name);
+}
+
 struct dyn_arch_ftrace {
 };
 #endif
-- 
2.39.2