This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] [PATCH] xen: convert p2m to a 3 level tree - partial rev


On Thu, Jan 27, 2011 at 10:25:08AM -0500, Konrad Rzeszutek Wilk wrote:
> On Thu, Jan 27, 2011 at 03:48:43PM +0100, Daniel Kiper wrote:
> > Hi,
> >
> > Durning work on Xen memory hotplug I discoverd that
> > 2.6.38-rc2 does not boot on domU. After some investigation
> > it appeared that 58e05027b530ff081ecea68e38de8d59db8f87e0
> > commit changed CONFIG_XEN_MAX_DOMAIN_MEMORY constant value
> > to 128. This change does not allow to boot kernel on domU
> > with small memory size (I could confirm that it is even
> > not possible to boot kernel on domU with 2 GiB). Guest
> Strange.. I've been booting with 1G, 2G, 3G, 4G guests.
> Could you give more details? Is this a 32-bit guest? 64-bit?
> What does your xm file look like?
> > crash silently without any warning. Durning further
> > research I found out that there is another commit published
> > recently (8e1b4cf2108488ccfb9a3e7ed7cd85a435e01d4b) which attempts
> > to fix this issue, however, it does not work on my platform.
> > I decided to reenable CONFIG_XEN_MAX_DOMAIN_MEMORY option in
> > kernel config and enable users to choose resonable values for
> > their machines until better fix will be published. I think this
> > solution is good because allow users to boot domU with newest
> > kernel and allow developers to continue their work without
> > time presure which could lead to new bugs.
> I think you are hitting a completly different bug. This
> patch of yours changes the size of the structure - so it could
> be that you are hitting a page-table overwrite. This is something
> that Stefano has been looking at - you might want to take a look at
> "x86: When destroying mappings between _brk_end and _end, do not go over _end"
> (it is present in his git tree).

It appears that this patch fixed issue described above. In this
situation I think it should be applied ASAP to RC and stable kernels.

Thank you for your help.


Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>