Re: [PATCH v2] mm: memory-failure: convert to pr_fmt()

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 27 Jul 2022 11:25:11 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:

> Use pr_fmt to prefix all pr_<level> output, but unpoison_memory()
> and soft_offline_page() are used by error injection, which have
> own prefixes like "Unpoison:" and "soft offline:", meanwhile,
> soft_offline_page() could be used by memory hotremove, so undef
> pr_fmt before unpoison_pr_info definition to keep the original
> output for them.
> 
> ...
>
> @@ -2289,6 +2285,7 @@ static int __init memory_failure_init(void)
>  }
>  core_initcall(memory_failure_init);
>  
> +#undef pr_fmt
>  #define unpoison_pr_info(fmt, pfn, rs)			\
>  ({							\
>  	if (__ratelimit(rs))				\

This change makes the build fail.

In file included from ./include/linux/kernel.h:29,
                 from mm/memory-failure.c:39:
mm/memory-failure.c: In function 'unpoison_memory':
./include/linux/printk.h:537:26: error: expected ')' before 'pr_fmt'
  537 |         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
      |                          ^~~~~~
./include/linux/printk.h:388:42: note: in definition of macro '__printk_index_emit'
  388 |                 if (__builtin_constant_p(_fmt) && __builtin_constant_p(_level)) { \
      |                                          ^~~~
./include/linux/printk.h:464:26: note: in expansion of macro 'printk_index_wrap'
  464 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
      |                          ^~~~~~~~~~~~~~~~~
./include/linux/printk.h:537:9: note: in expansion of macro 'printk'
  537 |         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
      |         ^~~~~~
mm/memory-failure.c:2292:17: note: in expansion of macro 'pr_info'
 2292 |                 pr_info(fmt, pfn);                      \
      |                 ^~~~~~~
mm/memory-failure.c:2326:17: note: in expansion of macro 'unpoison_pr_info'
 2326 |                 unpoison_pr_info("Unpoison: Disabled after HW memory failure %#lx\n",
      |                 ^~~~~~~~~~~~~~~~

[1500 lines of the same]