9front - general discussion about 9front
 help / color / mirror / Atom feed
From: cinap_lenrek@felloff.net
To: 9front@9front.org
Subject: Re: [9front] kernel crash in bhyve
Date: Fri, 11 Dec 2020 15:27:44 +0100	[thread overview]
Message-ID: <0EE47D607AC47ADDD13CB3D571814581@felloff.net> (raw)
In-Reply-To: <59540567-ACE4-46A1-8B60-78B9BBF78187@gmail.com>

> That makes sense.  The registers are 0 with the correct offset.

> ; for(r in 0x2ff 0x0fe) io -r -M $r
> 0x0
> 0x0


Yes, that explains it. This also means MTRR's are disabled in MTRRdeftype register.

The processor manual says:

E (MTRRs enabled) flag, bit 11:
MTRRs are enabled when set; all MTRRs are disabled when clear,
and the UC memory type is applied to all of physical memory.

However, the MTRRCap is also 0, basically meaning we have 0
variable length MTRR's and no fixed MTRR support.

I can use that setting so conclude that MTRR's are not supported
instead of relying on CPUID and the sanity check in memory.c.

--
cinap

  reply	other threads:[~2020-12-11 14:32 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-09 18:18 Xiao-Yong Jin
2020-12-09 18:26 ` [9front] " Xiao-Yong Jin
2020-12-09 18:44   ` ori
2020-12-09 19:05 ` [9front] " cinap_lenrek
2020-12-09 19:42   ` Xiao-Yong Jin
2020-12-09 20:52     ` cinap_lenrek
2020-12-09 21:22       ` Xiao-Yong Jin
2020-12-09 22:04         ` cinap_lenrek
2020-12-09 22:36           ` Xiao-Yong Jin
2020-12-09 23:18             ` cinap_lenrek
2020-12-10  0:10               ` Xiao-Yong Jin
2020-12-10  0:45                 ` cinap_lenrek
2020-12-10 11:30                 ` cinap_lenrek
2020-12-10 20:37                   ` Xiao-Yong Jin
2020-12-10 23:12                     ` Nick Owens
2020-12-11  4:55                       ` Xiao-Yong Jin
2020-12-11 14:27                         ` cinap_lenrek [this message]
2020-12-11  1:12                   ` ori

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=0EE47D607AC47ADDD13CB3D571814581@felloff.net \
    --to=cinap_lenrek@felloff.net \
    --cc=9front@9front.org \
    /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).