Re: [PATCH v3 00/11] xen: Initial kexec/kdump implementation

Daniel Kiper
2012-12-27T23:41:15Z

> On 12/26/2012 06:18 PM, Daniel Kiper wrote:
> > Hi,
> >
> > This set of patches contains initial kexec/kdump implementation for Xen v3.
> > Currently only dom0 is supported, however, almost all infrustructure
> > required for domU support is ready.
> >
> > Jan Beulich suggested to merge Xen x86 assembler code with baremetal x86 code.
> > This could simplify and reduce a bit size of kernel code. However, this solution
> > requires some changes in baremetal x86 code. First of all code which establishes
> > transition page table should be moved back from machine_kexec_$(BITS).c to
> > relocate_kernel_$(BITS).S. Another important thing which should be changed in that
> > case is format of page_list array. Xen kexec hypercall requires to alternate physical
> > addresses with virtual ones. These and other required stuff have not been done in that
> > version because I am not sure that solution will be accepted by kexec/kdump maintainers.
> > I hope that this email spark discussion about that topic.
>
> I want a detailed list of the constraints that this assumes and
> therefore imposes on the native implementation as a result of this. We
> have had way too many patches where Xen PV hacks effectively nailgun
> arbitrary, and sometimes poor, design decisions in place and now we
> can't fix them.

OK but now I think that we should leave this discussion
until all details regarding kexec/kdump generic code
will be agreed. Sorry for that.

Daniel