Arnd Bergmann b07829d546 vsnprintf: drop __printf() attributes on binary printing functions ...

The printf() format attributes are applied inconsistently for the binary
printf helpers, which causes warnings for the bpf_trace code using
them from functions that pass down format strings:

    kernel/trace/bpf_trace.c: In function '____bpf_trace_printk':
    kernel/trace/bpf_trace.c:377:9: error: function '____bpf_trace_printk' might be a candidate for 'gnu_printf' format attribute [-Werror=suggest-attribute=format]
      377 |         ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args);
          |         ^~~

This can be addressed either by annotating all five callers in bpf code,
or by removing the annotations on the callees that were added by Andy
Shevchenko last year.

As Alexei Starovoitov points out, there are no callers in C code that
would benefit from the __printf attributes, the only users are in BPF
code or in the do_trace_printk() helper that already checks the arguments.

Drop all three of these annotations, reverting the earlierl commits that
added these, in order to get a clean build with -Wsuggest-attribute=format.

Fixes: 6b2c1e30ad ("seq_file: Mark binary printing functions with __printf() attribute")
Fixes: 7bf819aa99 ("vsnprintf: Mark binary printing functions with __printf() attribute")
Link: https://lore.kernel.org/all/CAADnVQK3eZp3yp35OUx8j1UBsQFhgsn5-4VReqAJ=68PaaKYmg@mail.gmail.com/
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512061640.9hKTnB8p-lkp@intel.com/
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Acked-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260204132643.1302967-1-arnd@kernel.org
Signed-off-by: Petr Mladek <pmladek@suse.com>

2026-02-06 10:07:22 +01:00

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