Re: [merged] seq_buf-add-seq_buf_do_printk-helper.patch removed from -mm tree

[SeongJae Park <sj@kernel.org>]

Hi Andrew,

On Fri, 05 May 2023 15:45:21 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:

> 
> The quilt patch titled
>      Subject: seq_buf: add seq_buf_do_printk() helper
> has been removed from the -mm tree.  Its filename was
>      seq_buf-add-seq_buf_do_printk-helper.patch
> 
> This patch was dropped because it was merged into mainline or a subsystem tree

Just for headup.  I just found the latest mm-unstable indeed dropped the patch
but a patch[1] depends on it.  As a result, build fails as below.

      CC      mm/memcontrol.o
    /mm/memcontrol.c: In function ‘mem_cgroup_print_oom_meminfo’:
    /mm/memcontrol.c:1693:2: error: implicit declaration of function ‘seq_buf_do_printk’; did you mean ‘seq_buf_bprintf’? [-Werror=implicit-function-declaration]
     1693 |  seq_buf_do_printk(&s, KERN_INFO);
          |  ^~~~~~~~~~~~~~~~~
          |  seq_buf_bprintf
    cc1: some warnings being treated as errors

[1] https://lore.kernel.org/mm-commits/20230502201509.B8711C433D2@smtp.kernel.org/


Thanks,
SJ

> 
> ------------------------------------------------------
> From: Sergey Senozhatsky <senozhatsky@chromium.org>
> Subject: seq_buf: add seq_buf_do_printk() helper
> Date: Sat, 15 Apr 2023 19:01:10 +0900
> 
> (akpm: temporary addition for
> memcg-use-seq_buf_do_printk-with-mem_cgroup_print_oom_meminfo.patch)
> 
> Sometimes we use seq_buf to format a string buffer, which we then pass to
> printk().  However, in certain situations the seq_buf string buffer can
> get too big, exceeding the PRINTKRB_RECORD_MAX bytes limit, and causing
> printk() to truncate the string.
> 
> Add a new seq_buf helper.  This helper prints the seq_buf string buffer
> line by line, using as a delimiter, rather than passing the whole string
> buffer to printk() at once.
> 
> Link: https://lkml.kernel.org/r/20230415100110.1419872-1-senozhatsky@chromium.org
> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
> Cc: Yosry Ahmed <yosryahmed@google.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>