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Date:   Wed, 17 May 2023 19:19:32 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Luca Weiss <luca.weiss@fairphone.com>
Cc:     Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Jonathan Corbet <corbet@lwn.net>,
        ~postmarketos/upstreaming@lists.sr.ht, phone-devel@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] docs: printk-formats: Clarify %*pb format parameters
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References: <20230516-printk-bitmap-v1-1-d5f810192a10@fairphone.com>
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On Tue, May 16, 2023 at 08:52:43AM +0200, Luca Weiss wrote:
> Since it's rather unusual for printk formats to require two parameters,

I don't think this is "unusual". The %*... is very well described in the
printf(3) (the meaning of *). It applies here for %*p... as well.

> expand the documentation to clearly mention that in the printk format
> for bitmaps.
> 
> As an extra example, for example from include/net/bluetooth/hci_core.h
> we have a bitmap DECLARE_BITMAP(dev_flags, __HCI_NUM_FLAGS);
> This can be printed with ("%*pb", __HCI_NUM_FLAGS, hdev->dev_flags)

I think this change is not needed. But try to convince PRINTK maintainers.
Maybe they will be okay with it if it covers all %*p... cases (like %*ph).

-- 
With Best Regards,
Andy Shevchenko