Re: [PATCH] tracing: Have memmapped ring buffer use ioctl of "R" range 0x20-2F

[Google]

On Tue, 2 Jul 2024 15:33:54 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>
> 
> To prevent conflicts with other ioctl numbers to allow strace to have an
> idea of what is happening, add the rang of ioctls for the trace buffer
> mapping from _IO("T", 0x1) to the range of "R" 0x20 - 0x2F.
> 
> Link: https://lore.kernel.org/linux-trace-kernel/20240630105322.GA17573@xxxxxxxxxxxx/
> 
> Reported-by: "Dmitry V. Levin" <ldv@xxxxxxxxx>
> Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>

Looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>

Thanks,

> ---
>  Documentation/userspace-api/ioctl/ioctl-number.rst | 1 +
>  include/uapi/linux/trace_mmap.h                    | 2 +-
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index a141e8e65c5d..9a97030c6c8d 100644
> --- a/Documentation/userspace-api/ioctl/ioctl-number.rst
> +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
> @@ -186,6 +186,7 @@ Code  Seq#    Include File                                           Comments
>  'Q'   all    linux/soundcard.h
>  'R'   00-1F  linux/random.h                                          conflict!
>  'R'   01     linux/rfkill.h                                          conflict!
> +'R'   20-2F  linux/trace_mmap.h
>  'R'   C0-DF  net/bluetooth/rfcomm.h
>  'R'   E0     uapi/linux/fsl_mc.h
>  'S'   all    linux/cdrom.h                                           conflict!
> diff --git a/include/uapi/linux/trace_mmap.h b/include/uapi/linux/trace_mmap.h
> index bd1066754220..c102ef35d11e 100644
> --- a/include/uapi/linux/trace_mmap.h
> +++ b/include/uapi/linux/trace_mmap.h
> @@ -43,6 +43,6 @@ struct trace_buffer_meta {
>  	__u64	Reserved2;
>  };
>  
> -#define TRACE_MMAP_IOCTL_GET_READER		_IO('T', 0x1)
> +#define TRACE_MMAP_IOCTL_GET_READER		_IO('R', 0x20)
>  
>  #endif /* _TRACE_MMAP_H_ */
> -- 
> 2.43.0
> 


-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>