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svgalib and the 2.6.11 kernel

i recently rolled a 2.6.11.10 kernel and am happy with it
for the most part...however, svgalib stopped functioning.
now i receive 'svgalib: mmap error rrr'. i have also tried
updating to svgalib-1.9.21, but that didn't work either.

currently, i have just reverted back to my 2.6.7 kernel
where everything works...but i would like to make the
transition. (for instance, i noticed the pts behaviour is much
better under 2.6.11)

is this just a versioning conflict?
should i just wait for svgalib to support the new kernel?
or have i overlooked something simple?

Compare the framebuffer part in both kernels and spot the differences.

i don't use framebuffer

the kernels are virtually identical in configuration
with the exception i added v4l to 2.6.11.10...

Re: svgalib and the 2.6.11 kernel

Quote:

Originally posted by kodon
i recently rolled a 2.6.11.10 kernel and am happy with it
for the most part...however, svgalib stopped functioning.
now i receive 'svgalib: mmap error rrr'.

when do you get that error ?
at boot or...

egag

not at boot.

received it when trying to run xmame.svgalib...
already removed that kernel, but i will recompile
and test other svgalib apps.

i remember there was a problem with the
setuid bit, but that was a number of stable
releases back. figured they would have cleaned
that up by now...

well, i tried 2.6.11.11 this time
and it was even worse...

linux-wlan-ng wouldn't even work.

so i'll just stick with 2.6.7 for now.
maybe they will get the bugs out
by the 2.8 kernel...

The linux-wlan-ng problem is because it's kernel dependant, kernel modules are included in the package, so I guess you'll have to recompile those modules along with your kernel. Check that there are two packages, one for 2.4.X kernel and other for 2.6.X but they're kernel specific.

About the svgalib error, I've found a patch for 2.6.9+ kernels, it seems it's a bug in it, that's why you get mmap error rrr.
Here's the patch: http://xentac.net/tur/tags/link/svga...3-debian.patch
I'm quoting the relevant part:

Quote:

#DPATCHLEVEL=1

On Linux kernels >= 2.6.9 and the introduction of flexmmap has revealed
a bug in the return value test code.

diff -Naur svgalib-1.4.3.orig/src/vga.c svgalib-1.4.3/src/vga.c
--- svgalib-1.4.3.orig/src/vga.c 2004-10-22 22:59:38.000000000 +0200
+++ svgalib-1.4.3/src/vga.c 2004-10-22 23:08:26.000000000 +0200
@@ -2001,8 +2001,8 @@
};
__vga_mmap();

- if ((long) GM < 0) {
- printf("svgalib: mmap error rrr\n");
+ if (GM == MAP_FAILED) {
+ printf("svgalib: mmap error: %s\n", strerror(errno));
exit(1);
}
/* disable video */

You can do this by hand, just open that file (svgalib-1.4.3/src/vga.c) with a text editor and change the lines:

Code:

if ((long) GM < 0) {

printf("svgalib: mmap error rrr\n");

Code:

if (GM == MAP_FAILED) {

printf("svgalib: mmap error: %s\n", strerror(errno));

and recompile svgalib. You can get the source and it's SlackBuild to build from
ftp://ftp.scarlet.be/pub/slackware/s...rce/l/svgalib/ or Slackware CD 3 or 4 if you have them.

of course i rebuilt the linux-wlan-ng modules
after compiling a new kernel...

anyways...it's not that important to me to be on
the cutting edge. was just curious as to what
was broken...i can wait for a stable stable release.

thank you

update

just went to 2.6.12 (it likes wlan...woohoo)
tried the svgalib patch, but i couldn't get it to compile
using the slackbuild or standard procedure...

so i tried going to svgalib-1.9.21 again and it's working