Bug 326881 – sys-apps/kexec-tools-2.0.0-r1 wont work properly with XEN

• Status: RESOLVED UPSTREAM
• Product: Gentoo Linux

[Description DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 15:27:38 UTC]

I boot with

title   Gentoo Linux (2.6.34-xen-Gentoo-uranus-1-19 works XEN dualH)
root    (hd1,0)
kernel  /xen.gz iommu_=1 dom0_mem_=512M
module  /vmlinuz-2.6.34-xen-Gentoo-uranus-1-19 root=/dev/md5 ro odmraid \
        root_=UUID=3ae46540:5da32e75:3b8ef3b3:48c699fd \
        xen-pciback.hide_=(03:00.0)(03:00.1) \
        loop.max_part=63 max_part=63 panic=30 quiet_ noresume_ \
        vga_a=794 vga_a=4 video_o=1280x1024 vga_a=normal nomodeset
#module /initramfs-x86_64-2.6.31-gentoo-r6-Gentoo-uranus-1-04
savedefault

under console, i did
kexec /boot/vmlinuz-2.6.34-xen-Gentoo-uranus-1-19

and I ended up in the BIOS.

I re-started with init=/bin/bash
then
loadkeys fr
mount -o remount,rw,sync /dev/md5 /
mount -t proc proc /proc/

then
kexec -l /boot/vmlinuz-2.6.34-xen-Gentoo-uranus-1-19
kexec -e
and, I saw my raid devices remounted RO, sync, and then, a fatal error like
<<SYS_CALL_KEXEC should not return>>
and had the 30s waiting message (with few more unrelevant lines)

I restarted exactly the same process after replacing vmlinuz-2.6.34-xen-Gentoo-uranus-1-19 with vmlinuz-2.6.34-gentoo-r1-Gentoo-uranus-1-20 ... and, I could boot the kernel directly.

I mean, I did not try to boot the full system with the non xen kernel (I leave that basic test to normal users); but with kernel vmlinuz-2.6.34-gentoo-r1-Gentoo-uranus-1-20 init=/bin/bash ... kexec -l & kexec -e, I could see the kernel boot (and it ended up in could not mount root because I don't mind).

I don't where the problem could be:
- xen surveillor
- xen kernel
- kexec command
but something is not working as it should.

[Comment 1 DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 15:28:53 UTC]

Created attachment 237449 [details]
/boot/config-2.6.34-xen-Gentoo-uranus-1-19

the conf that does not work with kexec, compiled against sys-kernel/xen-sources-2.6.34

[Comment 2 DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 15:29:36 UTC]

Created attachment 237451 [details]
/boot/config-2.6.34-gentoo-r1-Gentoo-uranus-1-20

The conf that works compiled with sys-kernel/gentoo-sources-2.6.34-r1

[Comment 3 DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 15:30:00 UTC]

Created attachment 237453 [details]
/tmp/emerge--info

Good luck.

[Comment 4 DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 15:59:47 UTC]

in fact, i suddenyl wonder if kexec should reload vmlinuz, or the xen surveillor ...

[Comment 5 DEMAINE Benoît-Pierre, aka DoubleHP 2010-07-04 17:42:21 UTC]

I have tried (after init=/bin/bash) (from a dom0)
kexec -d -t multiboot-x86 -l /boot/xen.gz --module="/boot/vmlinuz-2.6.34-xen-Gentoo-uranus-1-19"

but i had no good result; it stopped MDs, tried to switch to new kernel, and the screen stayed as is for 10mn.

[Comment 6 Tim Harder 2010-11-29 20:24:51 UTC]

Does XEN work with the latest version of kexec-tools (2.0.2)?

[Comment 7 DEMAINE Benoît-Pierre, aka DoubleHP 2010-12-06 10:55:45 UTC]

Booted  my Xen kernel, did "reboot", saw "kexec loading foobar" ... in the BIOS (after clean shutdown). Kexec works fine when dom0 is desactivated with exactly the same kernel (same source tree with Xen symboles disabled).

Probably upstream issue. But, as long as there is no official dom0 support in verbatim Linux ... 

[Comment 8 Justin Lecher (RETIRED) 2012-03-04 13:00:00 UTC]

There were some XEN related changes in 2.0.3. Is this issue fixed?

[Comment 9 Norbert Marx 2012-07-09 19:32:45 UTC]

fixed with sys-apps/kexec-tools-2.0.3-r1; tested on amd64 with Opteron 1220 and Core i5

[Comment 10 Justin Lecher (RETIRED) 2012-07-10 05:53:59 UTC]

okay closing then