retitle 637675 squeeze 2.6.32 smp guest don't boot randomly thanks On 15.08.2011 18:36, Miguel Mismo wrote: > --- El lun, 15/8/11, Michael Tokarev <m...@tls.msk.ru> escribió: > >> Ok, that gives us something as a starting point. Now to find >> out what breaks when you start it from libvirt. >> Several vCPUs? > > Yes, I repeated the testing process, and the problem appears to arise > when in machine's xml, i increment > > <vcpu>1</vcpu> > > to > > <vcpu>2</vcpu> > > When I use only one virtual CPU, also with libvirt, it alaways boot > correctly. > > If i use multiple of them, then it fails to boot as reported in the bug.
Please excuse me for a long delay replying to this. I retitled the bug to include "smp" to reflect the fact that it only happens with smp guests. This is very important. In initial report you mentioned: > They get stuck at 'Loading, please wait...', leaving > CPU usage at 0% and non showing any message. In order to debug this, you may enable boot messages. For this, while in grub menu, hit "e" (for Edit) at the entry you're about to boot, scroll to line starting with "linux" - it should end with "quiet" word, or include that word somewhere -- remove this word and hit Ctrl+x to boot the modified entry. After this, kernel will show all boot messages on the screen, and you'll be able to see where it hangs. I suspect it is hanging in a timer-related code, -- there were several bugs fixe in 2.6.32 kernels related to "virtual" timers... > Ok, in stock squeeze guest it is: > > ii linux-image-2.6-amd64 2.6.32+29 > Linux 2.6 for 64-bit PCs (meta-package) > ii linux-image-2.6.32-5-amd64 2.6.32-35 > Linux 2.6.32 for 64-bit PCs ..but you said your guest kernel is quite recent (2.6.32-35 is new enough, which should include all required fixes). The same kernel is used on host as well, as far as I can see -- 2.6.32-35. So, I'm not really sure what to do here. Can you check if the problem is still exists with current kernels as well? One more thing I noticed: you're using older AMD CPU -- "AMD Athlon(tm) 64 X2 Dual Core Processor 4000+" -- that's their first-generation X2-64 which does not have synced TSC (this is a time stamp counter register in CPU, and in these models it shows different values for different cores). Do you have cpu frequency scaling enabled on the host? If yes, it is worth to try to disable it. Anyway, please boot with non-verbose mode and see where it hangs. From this point it will be more clear what's going on. One additional tip: you can save boot messages in a file by adding: -serial file:/some/where/file/name to qemu-kvm command line, and to add console=ttyS0 console=tty1 to the linux line in grub (the same line where you want to remove the "quiet" parameter). Yes this is 2 consoles, to show messages in two places - on regular guest screen and on serial line. Thank you! /mjt -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
