From: Jacek Tomaka <jacek.tomaka@poczta.fm>
To: Boris Petkov <bp@alien8.de>
Cc: Jacek Tomaka <jacekt@dugeo.com>,
Thomas Gleixner <tglx@linutronix.de>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/microcode: allow non-root reading of microcode version and processor flags
Date: Sun, 26 Aug 2018 20:23:48 +0800 [thread overview]
Message-ID: <CD5DA006-0D28-4CB9-95FA-231F0E20BF44@poczta.fm> (raw)
In-Reply-To: <8DACDEF8-ED0A-42BF-8426-3AAA4BA16317@alien8.de>
> On 26 Aug 2018, at 7:52 pm, Boris Petkov <bp@alien8.de> wrote:
>
>> On August 25, 2018 6:50:39 AM GMT+03:00, Jacek Tomaka <jacekt@dugeo.com> wrote:
>> /sys/devices/system/cpu/cpuX/microcode
>>
>> Before:
>> -r-------- processor_flags
>> -r-------- version
>>
>> After:
>> -r--r--r-- processor_flags
>> -r--r--r-- version
>>
>> Microcode version has been already readable for non root users via
>> /proc/cpuinfo. However it is easier to access it from
>> /sys/devices/system/cpu/cpuX/microcode/version
>
> Easier than /proc/cpuinfo?! Sorry, not really.
Why not?
> You'd need to elaborate in greater detail what exactly you're trying to achieve.
I am trying to get microcode version from user space. Reading it from /proc/cpuinfo requires greping/awking to extract the bits of information that are readily available in microcode/version.
Any reason why the same piece of information has different access permissions, depending on the way it is accessed?
Regards.
Jacek Tomaka
next prev parent reply other threads:[~2018-08-26 12:39 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-25 3:50 [PATCH] x86/microcode: allow non-root reading of microcode version and processor flags Jacek Tomaka
2018-08-26 11:52 ` Boris Petkov
2018-08-26 12:23 ` Jacek Tomaka [this message]
2018-08-27 4:06 ` Borislav Petkov
[not found] ` <CAKVxXCUMy97PzmB=zrMg_kemLooA3LHTvAPruQh2w41CU=B+Dg@mail.gmail.com>
2018-08-27 7:30 ` Borislav Petkov
2018-08-27 7:52 ` Borislav Petkov
2018-08-27 8:05 ` Jacek Tomaka
2018-08-27 14:50 ` Borislav Petkov
2018-09-02 12:12 ` [tip:x86/microcode] x86/microcode: Make revision and processor flags world-readable tip-bot for Jacek Tomaka
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CD5DA006-0D28-4CB9-95FA-231F0E20BF44@poczta.fm \
--to=jacek.tomaka@poczta.fm \
--cc=bp@alien8.de \
--cc=jacekt@dugeo.com \
--cc=linux-kernel@vger.kernel.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).