From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: xen ballon errors in kernel logs even if I disabled it after kernel upgrade from 3.2 to 3.14 Date: Thu, 11 Dec 2014 10:48:23 +0000 Message-ID: <54897677.6000406@citrix.com> References: <542529E3.9080104@m2r.biz> <54253E5C.5090002@citrix.com> <54255208.1080904@m2r.biz> <542555C3.1030606@citrix.com> <5489668C.6030506@m2r.biz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5489668C.6030506@m2r.biz> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Fabio Fantoni , David Vrabel , xen-devel Cc: ian Campbell List-Id: xen-devel@lists.xenproject.org On 11/12/14 09:40, Fabio Fantoni wrote: > Il 26/09/2014 14:02, David Vrabel ha scritto: >> On 26/09/14 12:46, Fabio Fantoni wrote: >>> Il 26/09/2014 12:22, David Vrabel ha scritto: >>>> On 26/09/14 09:54, Fabio Fantoni wrote: >>>>> Yesterday I updated wheezy kernel (3.2) to 3.14 from >>>>> wheezy-backports to >>>>> solves one critical network problem with new windows pv driver. >>>>> Today I saw the kernel logs full of this error: >>>>> xen:balloon: reserve_additional_memory: add_memory() failed: -17 >>>> Fixed by: >>>> >>>> 3dcf63677d4eb7fdfc13290c8558c301d2588fe8 (xen/balloon: cancel >>>> ballooning >>>> if adding new memory failed) >>>> >>>> Ballooned memory is required by backends which is why you're seeing it >>>> even with auto-ballooning disabled. >>>> >>>> David >>>> >>> Thanks for your reply. >>> Is correct that show it also if dom0 have fixed memory size and xl.conf >>> have balloning disabled? >> Yes. >> >>> Can this problem cause a crash or other important aftermath? >> No. It's harmless. >> >>> Can you apply or request the backport of this fix to stable branchs? >> No. A fix for a harmless log message is not critical enough for stable. >> >> David > > Thanks for your reply. > New debian kernel is freezed to 3.16 version without this fix > (3.16.7-ckt2-1), I not found a workaround for it, even with dom0 mem > fixed and autoballoning disabled I still have big syslog and kern.log > full of these messages when I start 1 or more domUs that make difficult > see other parts of logs. > And another strange thing that I not understand is why older kernel > (3.2) not have this problem. > Someone has advices about it please? You can workaround it by pre-ballooning dom0 with a Xen command line option such as dom0_mem=4G,max:5G Don't have too much ballooned memory or dom0 may run out of memory and not boot or run very slowly. You can also disable XEN_BALLOON_MEMORY_HOTPLUG. David