From: Andrew Kirilenko <icedank@gmx.net>
To: linux-kernel@vger.kernel.org
Subject: Re: Stored data missed in setup.S
Date: Wed, 23 Apr 2003 17:50:50 +0300 [thread overview]
Message-ID: <200304231750.50553.icedank@gmx.net> (raw)
In-Reply-To: <Pine.LNX.4.53.0304231028270.23276@chaos>
Hello!
>
> [SNIPPED...]
>
> > OK. And now code looks like:
> > -->
> > start_of_setup: # line 160
> > # bla bla bla - some checking code
> > movb $1, %al
> > movb %al, (0x100)
> > ....
> > ....
> > cmpb $1, (0x100)
> > je bail820 # and it DON'T jump here
> > <--
> >
> >
> > I'm sure, I'm doing something wrong. But what???
>
> The only possibiity is that the code you just showed is not
> being executed. Absolute location 0x100 is not being overwritten
> by some timer-tick (normally) so whatever you write there should
> remain. You just put a byte of 1 in that location and then
> you compared against a byte of 1. If the CPU was broken, you
> wouldn't have even loaded your code.
>
> It is quite likely that the IP is being diverted around your code
> by some previous code.
>
> FYI, you can check the progress of your code by 'printing' on
> the screen. Set up ES to point to the screen segment, and write
> letters there:
>
> movw $0xb800, %ax
> movb %ax, %es
> movb $'A', %es:(0)
>
> This 'prints' an 'A' at the first location on the screen.
Ha! I don't have video adapter not keyboard on that PC :)
And, when I change je to jmp it works perfectly.
Best regards,
Andrew.
next prev parent reply other threads:[~2003-04-23 14:38 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-04-23 13:17 Stored data missed in setup.S Andrew Kirilenko
2003-04-23 13:33 ` Richard B. Johnson
2003-04-23 13:39 ` Andrew Kirilenko
2003-04-23 14:36 ` Richard B. Johnson
2003-04-23 14:50 ` Andrew Kirilenko [this message]
2003-04-23 15:06 ` Richard B. Johnson
2003-04-23 14:51 ` Randy.Dunlap
2003-04-23 15:11 ` Richard B. Johnson
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=200304231750.50553.icedank@gmx.net \
--to=icedank@gmx.net \
--cc=linux-kernel@vger.kernel.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).