linux-kernel - Re: [PATCH 2/2] scripts/gdb: lx-dmesg: Use errors=replace for decoding

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Date:   Fri, 23 Jun 2017 18:02:43 +0200
From:   Jan Kiszka <jan.kiszka@...mens.com>
To:     Leonard Crestez <leonard.crestez@....com>,
        Kieran Bingham <kieran@...uared.org.uk>
Cc:     linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] scripts/gdb: lx-dmesg: Use errors=replace for
 decoding

On 2017-06-23 16:20, Leonard Crestez wrote:
> It is never desirable lx-dmesg to fail on string decoding errors, not
> even if the log buffer is corrupt.
> 
> Signed-off-by: Leonard Crestez <leonard.crestez@....com>
> ---
>  scripts/gdb/linux/dmesg.py | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/scripts/gdb/linux/dmesg.py b/scripts/gdb/linux/dmesg.py
> index 6f8d2b2..d0cac58 100644
> --- a/scripts/gdb/linux/dmesg.py
> +++ b/scripts/gdb/linux/dmesg.py
> @@ -52,13 +52,13 @@ class LxDmesg(gdb.Command):
>                  continue
>  
>              text_len = utils.read_u16(log_buf[pos + 10:pos + 12])
> -            text = log_buf[pos + 16:pos + 16 + text_len].decode()
> +            text = log_buf[pos + 16:pos + 16 + text_len].decode(errors='replace')

pep8 should complain.

>              time_stamp = utils.read_u64(log_buf[pos:pos + 8])
>  
>              for line in text.splitlines():
>                  gdb.write("[{time:12.6f}] {line}\n".format(
>                      time=time_stamp / 1000000000.0,
> -                    line=line))
> +                    line=line.encode(errors='replace')))

You only talk about "decoding" in the commit log, but here you encode
back. An short explanation why this is also needed would be nice.

>  
>              pos += length
>  
> 

Jan

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