Re: kvm-85 sometimes not starting on 2.6.30-rc5
Hi, somehow this thread ended without any conclusion. Today I noticed that BUG: MAX_LOCK_DEPTH too low! still shows up when starting kvm on 2.6.31-rc8 So is increasing MAX_LOCK_DEPTH to say 96 good way to go? If yes, shouldn't we set this for upstream kernel? thanks nik On Sun, May 24, 2009 at 12:47:49PM +0300, Avi Kivity wrote: Andrea Arcangeli wrote: On Sun, May 17, 2009 at 11:27:42PM +0300, Avi Kivity wrote: Andrea, looks like the mother of all locks below. eheh yes that really is the mother of all locks ;). So the thing is, like BUG says MAX_LOCK_DEPTH is too low, to fix you should rebuild after increasing it in include/linux/sched.h to say 96. Likely somebody changed qemu-kvm over time in a way that allocates more vmas than before. It does, we now have a vma for each discontiguous memory region (640K, vga bios, bios, 1M+ memory, framebuffer, 4G+ memory). Still, we have a lot more vmas in qemu for the various dynamic libraries, etc. I'm surprised it made such a difference. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- - Nikola CIPRICH LinuxBox.cz, s.r.o. 28. rijna 168, 709 01 Ostrava tel.: +420 596 603 142 fax:+420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: ser...@linuxbox.cz - -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: kvm-85 sometimes not starting on 2.6.30-rc5
Andrea Arcangeli wrote: On Sun, May 17, 2009 at 11:27:42PM +0300, Avi Kivity wrote: Andrea, looks like the mother of all locks below. eheh yes that really is the mother of all locks ;). So the thing is, like BUG says MAX_LOCK_DEPTH is too low, to fix you should rebuild after increasing it in include/linux/sched.h to say 96. Likely somebody changed qemu-kvm over time in a way that allocates more vmas than before. It does, we now have a vma for each discontiguous memory region (640K, vga bios, bios, 1M+ memory, framebuffer, 4G+ memory). Still, we have a lot more vmas in qemu for the various dynamic libraries, etc. I'm surprised it made such a difference. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: kvm-85 sometimes not starting on 2.6.30-rc5
On Sun, May 17, 2009 at 11:27:42PM +0300, Avi Kivity wrote: Andrea, looks like the mother of all locks below. eheh yes that really is the mother of all locks ;). So the thing is, like BUG says MAX_LOCK_DEPTH is too low, to fix you should rebuild after increasing it in include/linux/sched.h to say 96. Likely somebody changed qemu-kvm over time in a way that allocates more vmas than before. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
kvm-85 sometimes not starting on 2.6.30-rc5
Hi, sometimes trying to start kvm on 2.6.30-rc5 (with kvm module v85, userspace v85) fails with: kvm_create_vm: Interrupted system call Could not create KVM context and following backtrace appears in dmesg: [ 309.546138] BUG: MAX_LOCK_DEPTH too low! [ 309.549964] turning off the locking correctness validator. [ 309.549964] Pid: 2833, comm: qemu-kvm Not tainted 2.6.30lb.00_01_PRE08 #1 [ 309.549964] Call Trace: [ 309.549964] [80269aa9] __lock_acquire+0x4a9/0xb70 [ 309.549964] [802c54ef] ? mm_take_all_locks+0x2f/0x130 [ 309.549964] [8026b825] lock_acquire+0xa5/0x150 [ 309.549964] [802c55ac] ? mm_take_all_locks+0xec/0x130 [ 309.549964] [80505c96] _spin_lock_nest_lock+0x36/0x50 [ 309.549964] [802c55ac] ? mm_take_all_locks+0xec/0x130 [ 309.549964] [802c55ac] mm_take_all_locks+0xec/0x130 [ 309.549964] [802d43ab] do_mmu_notifier_register+0x7b/0x1d0 [ 309.549964] [802d451e] mmu_notifier_register+0xe/0x10 [ 309.549964] [a02a8dd9] kvm_dev_ioctl+0x189/0x2f0 [kvm] [ 309.549964] [802f0171] vfs_ioctl+0x31/0x90 [ 309.549964] [802f03fb] do_vfs_ioctl+0x22b/0x550 [ 309.549964] [802f07a2] sys_ioctl+0x82/0xa0 [ 309.549964] [8020b442] system_call_fastpath+0x16/0x1b It happened to me when I didn't have storage with kernel mounted. Further attempts are usually successfull. BR nik -- - Nikola CIPRICH LinuxBox.cz, s.r.o. 28. rijna 168, 709 01 Ostrava tel.: +420 596 603 142 fax:+420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: ser...@linuxbox.cz - -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
