From: "Barry K. Nathan" <barryn@pobox.com>
To: marcelo@conectiva.com.br, arjanv@redhat.com
Cc: alan@lxorguk.ukuu.org.uk, m.c.p@wolk-project.de,
linux-kernel@vger.kernel.org
Subject: [PATCH] *really* fix ioperm in 2.4
Date: Fri, 23 May 2003 02:58:56 -0700 [thread overview]
Message-ID: <20030523095856.GA2310@ip68-101-124-193.oc.oc.cox.net> (raw)
The previous 2.4 ioperm fix is broken. This patch against 2.4.21-rc3
fixes the fix, so that ioperm actually works. The "fixed" ioperm was
only copying 1/4th of the bitmap, not the whole thing. The real-world
bug was that FCE Ultra (and possibly other svgalib apps) tended to
segfault rather than actually run.
This patch also backports the IO_BITMAP_BYTES #define from 2.5, because
IO_BITMAP_SIZE can be a mental booby trap in some contexts. If that's
too invasive, let me know, but IMO it makes the code cleaner and it's
an obviously correct change.
-Barry K. Nathan <barryn@pobox.com>
diff -ruN linux-2.4.21-rc3/arch/i386/kernel/ioport.c linux-2.4.21-rc3-bkn1/arch/i386/kernel/ioport.c
--- linux-2.4.21-rc3/arch/i386/kernel/ioport.c 2003-05-22 23:04:48.000000000 -0700
+++ linux-2.4.21-rc3-bkn1/arch/i386/kernel/ioport.c 2003-05-23 02:10:23.000000000 -0700
@@ -81,7 +81,7 @@
if (tss->bitmap == IO_BITMAP_OFFSET) { /* already active? */
set_bitmap(tss->io_bitmap, from, num, !turn_on);
} else {
- memcpy(tss->io_bitmap, t->io_bitmap, IO_BITMAP_SIZE);
+ memcpy(tss->io_bitmap, t->io_bitmap, IO_BITMAP_BYTES);
tss->bitmap = IO_BITMAP_OFFSET; /* Activate it in the TSS */
}
diff -ruN linux-2.4.21-rc3/arch/i386/kernel/process.c linux-2.4.21-rc3-bkn1/arch/i386/kernel/process.c
--- linux-2.4.21-rc3/arch/i386/kernel/process.c 2003-03-26 16:42:28.000000000 -0800
+++ linux-2.4.21-rc3-bkn1/arch/i386/kernel/process.c 2003-05-23 02:12:36.000000000 -0700
@@ -727,7 +727,7 @@
* is not really acceptable.]
*/
memcpy(tss->io_bitmap, next->io_bitmap,
- IO_BITMAP_SIZE*sizeof(unsigned long));
+ IO_BITMAP_BYTES);
tss->bitmap = IO_BITMAP_OFFSET;
} else
/*
diff -ruN linux-2.4.21-rc3/include/asm-i386/processor.h linux-2.4.21-rc3-bkn1/include/asm-i386/processor.h
--- linux-2.4.21-rc3/include/asm-i386/processor.h 2003-05-23 01:30:01.000000000 -0700
+++ linux-2.4.21-rc3-bkn1/include/asm-i386/processor.h 2003-05-23 02:08:15.000000000 -0700
@@ -281,6 +281,7 @@
* Size of io_bitmap in longwords: 32 is ports 0-0x3ff.
*/
#define IO_BITMAP_SIZE 32
+#define IO_BITMAP_BYTES (IO_BITMAP_SIZE * 4)
#define IO_BITMAP_OFFSET offsetof(struct tss_struct,io_bitmap)
#define INVALID_IO_BITMAP_OFFSET 0x8000
reply other threads:[~2003-05-23 9:45 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=20030523095856.GA2310@ip68-101-124-193.oc.oc.cox.net \
--to=barryn@pobox.com \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=arjanv@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=m.c.p@wolk-project.de \
--cc=marcelo@conectiva.com.br \
/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).