Re: balloon manipulation within a domU?

["Aaron J. Grier" <agrier%poofygoof.com@localhost>]

On Thu, Jul 26, 2012 at 11:12:25AM +0100, Cherry G. Mathew wrote:
> On 24 July 2012 07:33, Aaron J. Grier <agrier%poofygoof.com@localhost> wrote:
> > manipulating a NetBSD domU's memory seems to work fine with "xl
> > mem-set", but trying to manipulate this within the domU with "sysctl
> > -w machdep.xen.balloon.target=XXXX" yields "error 13, couldn't write
> > xenbus target node".
> 
> Could you post what
> # xenstore-ls
> 
> says from the dom0 ?
> There should be an entry for memory/target

there is such an entry, and I can change the target from the dom0 side.
I've attached the full output.

> > is there something I need to enable in my xen configuration to allow
> > a domU to do its own balloon requests?

the problem seems to be that the domU cannot write its own memory /
target entry.

thanks for looking at this.  hopefully it's something simple.

-- 
  Aaron J. Grier | "Not your ordinary poofy goof." | 
agrier%poofygoof.com@localhost

tool = ""
 xenstored = ""
local = ""
 pool = ""
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   uuid = "8e61052c-5226-deb1-5af3-7f6a04542768"
   name = "Pool-0"
 domain = ""
  0 = ""
   vm = "/vm/00000000-0000-0000-0000-000000000000"
   device = ""
   control = ""
    platform-feature-multiprocessor-suspend = "1"
   error = ""
   memory = ""
    target = "262144"
   guest = ""
   hvmpv = ""
   data = ""
   description = ""
   console = ""
    limit = "1048576"
    type = "xenconsoled"
   domid = "0"
   cpu = ""
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     19 = ""
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       dev = "hda3"
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       feature-flush-cache = "1"
     21 = ""
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      769 = ""
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       physical-device = "85"
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    videoram = "0"
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   device = ""
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      protocol = "x86_32-abi"
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      virtual-device = "770"
      device-type = "disk"
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      event-channel = "9"
      protocol = "x86_32-abi"
     771 = ""
      backend = "/local/domain/0/backend/vbd/22/771"
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      device-type = "disk"
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      protocol = "x86_32-abi"
     772 = ""
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      protocol = "x86_32-abi"
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      device-type = "disk"
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      protocol = "x86_32-abi"
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      feature-rx-notify = "1"
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      device-type = "cdrom"
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    videoram = "8192"
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    tty = "/dev/pts/7"
    vnc-port = "5900"
    vnc-listen = "127.0.0.1"
   image = ""
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vm = ""
 00000000-0000-0000-0000-000000000000 = ""
  on_xend_stop = "ignore"
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  uuid = "00000000-0000-0000-0000-000000000000"
  on_reboot = "restart"
  image = "(linux (kernel '') (superpages 0) (nomigrate 0) (tsc_mode 0))"
   ostype = "linux"
   kernel = ""
   cmdline = ""
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  on_poweroff = "destroy"
  bootloader_args = ""
  on_xend_start = "ignore"
  on_crash = "restart"
  xend = ""
   restart_count = "0"
  vcpus = "1"
  vcpu_avail = "1"
  bootloader = ""
  name = "Domain-0"
 34e8738f-6ad1-e111-8f78-20cf30f44958 = ""
  uuid = "34e8738f-6ad1-e111-8f78-20cf30f44958"
  name = "milo"
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  start_time = "1342679141.49"
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 2855e49d-9fd7-e111-8f78-20cf30f44958 = ""
  uuid = "2855e49d-9fd7-e111-8f78-20cf30f44958"
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  pool_name = "Pool-0"
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     frontend = "/local/domain/22/device/console/0"
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     backend = "/local/domain/0/backend/console/22/0"
 3649274a-aad7-e111-8f78-20cf30f44958 = ""
  uuid = "3649274a-aad7-e111-8f78-20cf30f44958"
  name = "damo"
  pool_name = "Pool-0"
  rtc = ""
   timeoffset = ""
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   ostype = "linux"
   kernel = ""
   cmdline = ""
   ramdisk = ""
  start_time = "1343366433.81"