linux-kernel - Re: [PATCH] rtc: cros-ec: Limit RTC alarm range if needed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 31 Oct 2022 09:36:47 -0700
From:   Brian Norris <briannorris@...omium.org>
To:     Tzung-Bi Shih <tzungbi@...nel.org>
Cc:     Guenter Roeck <linux@...ck-us.net>,
        Alessandro Zummo <a.zummo@...ertech.it>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        Benson Leung <bleung@...omium.org>, linux-rtc@...r.kernel.org,
        chrome-platform@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] rtc: cros-ec: Limit RTC alarm range if needed

On Mon, Oct 31, 2022 at 11:26:44AM +0800, Tzung-Bi Shih wrote:
> On Fri, Oct 28, 2022 at 05:54:00PM -0700, Guenter Roeck wrote:
> > Drop error messages in cros_ec_rtc_get() and cros_ec_rtc_set() since the
> > calling code also logs an error and to avoid spurious error messages if
> > setting the alarm ultimately succeeds.
> 
> It only retries for cros_ec_rtc_set().  cros_ec_rtc_get() doesn't emit
> spurious error messages.

All of cros_ec_rtc_get()'s callers were also logging the same message.
So it was redundant. I think the general strategy here was to log the
error(s) in callers (last point before we "exit" the driver), to have
the best chance at context-relevant error messages, or ignoring them
where proper.

It's already a bit dubious to log kernel messages at all in response to
normal sysfs operations. We probably want them in some cases, when
things are particularly unexpected, but it shouldn't be a regular
occurrence, and we certainly don't need *two* log lines for each error.

Technically, if one wants to be super-nitpicky about one purpose per
patch, then maybe a patch to trim the logging, and a patch to fix the
alarm range issues...
...but I think that would be a little silly, and perhaps even harmful.
They are related concerns that should be patched (and probably
backported) together.

Brian