Hi
Am 15.07.24 um 12:21 schrieb Tj:
Linux kernel v6.9 has changed the symlink to point to the parent device. This
breaks fbdev_open() detection logic. Change it to use the subsystem symlink
instead which will remain stable.
Kernel v6.8:
[ 14.067] (II) fbdev_open() sysfs_path=/sys/class/graphics/fb0
[ 14.067] (II) fbdev_open()
buf=../../devices/platform/vesa-framebuffer.0/graphics/fb0
Kernel v6.9:
[ 15.609] (II) fbdev_open() sysfs_path=/sys/class/graphics/fb0
[ 15.609] (II) fbdev_open()
buf=../../devices/pci0000:00/0000:00:01.0/vesa-framebuffer.0/graphics/fb0
Originally found in automated Debian ISO QA testing [0] and confirmed in Linux
[1].
Tested on kernels v6.9.7 and v6.8.12
[0] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1075713
[1]
https://lore.kernel.org/lkml/lLyvPFC_APGHNfyGNHRpQy5izBikkaTPOpHooZIT3fFAoJPquSI31ZMueA99XTdr8ysir3X7O7IMdc6za-0m79vr_claeparHhoRouVgHOI=@proton.me/
Fixes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1714
Signed-off-by: Tj <tj.iam...@proton.me>
Reviewed-by: Thomas Zimmermann <tzimmerm...@suse.de>
It might be more effective to open a merge request on
https://gitlab.freedesktop.org/xorg/xserver
Best regards
Thomas
---
hw/xfree86/fbdevhw/fbdevhw.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/xfree86/fbdevhw/fbdevhw.c b/hw/xfree86/fbdevhw/fbdevhw.c
index 76bc4809f..019af305b 100644
--- a/hw/xfree86/fbdevhw/fbdevhw.c
+++ b/hw/xfree86/fbdevhw/fbdevhw.c
@@ -378,9 +378,9 @@ fbdev_open(int scrnIndex, const char *dev, char **namep)
node++;
}
- if (asprintf(&sysfs_path, "/sys/class/graphics/%s", node) < 0 ||
+ if (asprintf(&sysfs_path, "/sys/class/graphics/%s/device/subsystem",
node) < 0 ||
readlink(sysfs_path, buf, sizeof(buf) - 1) < 0 ||
- strstr(buf, "devices/pci")) {
+ strstr(buf, "bus/pci")) {
free(sysfs_path);
close(fd);
return -1;
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)
