Schmidt Werner
2006-Nov-06 16:49 UTC
[Xen-users] Question on linux dom0/domU incompatibilities
Hi during an update of my test system from Xen 3.0.2. to Xen 3.0.3 i ran into problems with the domU start up: the dom0 kernel was installed from the xensource i386 rpm for RedHat 4.4 (kernel 2.6.16.29-xen_3.0.3.0), whereas the domU kernel was derived from the source tarball archive (+ some additional patches). The domU kernel did not start-up as it was unintentionally configured as non-PAE kernel (whereas the binary kernel is configured with PAE support) Now this mismatch with the resulting malfunction leads me to the more general question, which global config params of the dom0/domU kernel like SMP/PAE/i386/processor type? etc. must be chosen in a certain relation to avoid a malfunction of the system (thinking about a scenario, where the dom0 kernel comes from a certain distribution, whereas some domU kernels may be derived from some other source). I think a kind of list or matrix of ''known incompatibilities'' would be a great help for all users, who cannot make sure that the dom0 and domU kernels come from the same source/config basis. Thanks Werner _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Petersson, Mats
2006-Nov-07 10:16 UTC
RE: [Xen-users] Question on linux dom0/domU incompatibilities
________________________________ From: xen-users-bounces@lists.xensource.com [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Schmidt Werner Sent: 06 November 2006 16:49 To: xen-users@lists.xensource.com Subject: [Xen-users] Question on linux dom0/domU incompatibilities Hi during an update of my test system from Xen 3.0.2. to Xen 3.0.3 i ran into problems with the domU start up: the dom0 kernel was installed from the xensource i386 rpm for RedHat 4.4 (kernel 2.6.16.29-xen_3.0.3.0), whereas the domU kernel was derived from the source tarball archive (+ some additional patches). The domU kernel did not start-up as it was unintentionally configured as non-PAE kernel (whereas the binary kernel is configured with PAE support) Now this mismatch with the resulting malfunction leads me to the more general question, which global config params of the dom0/domU kernel like SMP/PAE/i386/processor type? etc. must be chosen in a certain relation to avoid a malfunction of the system (thinking about a scenario, where the dom0 kernel comes from a certain distribution, whereas some domU kernels may be derived from some other source). I think a kind of list or matrix of ''known incompatibilities'' would be a great help for all users, who cannot make sure that the dom0 and domU kernels come from the same source/config basis. Currently, x86-Xen supports three modes: 32-bit no-PAE (CONFIG_HGIHMEM64G not set) 32-bit PAE (CONFIG_HIGHMEM64G=y) 64-bit. (CONFIG_X86_64=y) You need to have exactly the same configuration for Dom0 and DomU [1]. SMP or not shouldn''t make any difference, other than obviously that you don''t get to use more than one processor in the kernel if you compile without SMP. [1] There is work in progress to get para-virtual 32-bit DomU to work on 64-bit Xen, but it''s still in progress rahter than completed. -- Mats Thanks Werner _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users