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Date: Sun, 25 Feb 2024 19:27:35 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Stefan Wahren <wahrenst@gmx.net>
Cc: Linus Walleij <linus.walleij@linaro.org>,
	Bartosz Golaszewski <brgl@bgdev.pl>,
	Kent Gibson <warthog618@gmail.com>, linux-gpio@vger.kernel.org,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: WARNING: fs/proc/generic.c:173 __xlate_proc_name
Message-ID: <fe33dcf1-79c0-4f56-8848-474caa014c10@p183>
References: <CACVxJT8T8u+XK7GnyCus19KDVqfquGbAM-0x8bSFgKTeqhD2Ug@mail.gmail.com>
 <c51a282a-bdbf-4ced-9fcf-e38a33152761@gmx.net>
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On Sun, Feb 25, 2024 at 11:47:30AM +0100, Stefan Wahren wrote:
> Hi Alexey,
> 
> Am 25.02.24 um 11:37 schrieb Alexey Dobriyan:
> > > WARNING: CPU: 0 PID: 429 at fs/proc/generic.c:173
> > > __xlate_proc_name+0x78/0x98 name 'R1/S1'
> > proc_mkdir() didn't find 'R1' directory.
> > 
> > In other words, you can't have slashes in irq names.
> we already came to the point in the discussion before (link in my last
> mail). The problem is no libgpiod user (userspace) is aware of this.

Changing '/' to '-' or '.' should be OK. Whatever you do, don't change
to '!' because it will make these paths annoying to use in bash.

> So the next question is where it should be fixed?

libgpiod silently weren't getting directory inside /proc/irq/${irq}
and nobody noticed until now.

I think returning error may be too harsh but replacing characters is not.

> Sorry, i took my original message because posting the last message to
> linux-fsdevel without context would be pointless.