public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Stas Sergeev <stssppnn@yahoo.com>
To: linux-kernel@vger.kernel.org
Subject: [patch] vm86: fix IOPL virtualisation
Date: Sun, 25 May 2003 21:33:29 +0400	[thread overview]
Message-ID: <3ED0FE69.6070503@yahoo.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 445 bytes --]

Hello.

The attached patch implements the following:
http://x86.ddj.com/articles/vme1/vme_overview.htm
---
In addition to moving the VIF to the IF on the stack image, 
PUSHF always pushes an IOPL image of 3 onto the
stack.
---

Many DOS programs, including dos4gw, are
checking if they are in a v86 mode by trying
to alter IOPL. With that patch they are not
get confused under dosemu.
Also the patch fixes what looks like a bug
with an IF flag.

[-- Attachment #2: v86_iopl.diff --]
[-- Type: text/plain, Size: 297 bytes --]

--- linux/arch/i386/kernel/vm86.c	Sun Aug  4 03:44:30 2002
+++ linux/arch/i386/kernel/vm86.c	Sat May 24 19:30:45 2003
@@ -362,6 +362,9 @@
 
 	if (VEFLAGS & VIF_MASK)
 		flags |= IF_MASK;
+	else
+		flags &= ~IF_MASK;
+	flags |= IOPL_MASK;
 	return flags | (VEFLAGS & current->thread.v86mask);
 }
 

                 reply	other threads:[~2003-05-25 17:23 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=3ED0FE69.6070503@yahoo.com \
    --to=stssppnn@yahoo.com \
    --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