On Tue, Aug 02, 2011 at 11:08:07AM +0200, Michael Holzheu wrote: > Hello Vivek, > > #On Mon, 2011-08-01 at 16:36 -0400, Vivek Goyal wrote: > > On Wed, Jul 27, 2011 at 02:55:07PM +0200, Michael Holzheu wrote: > > > From: Michael Holzheu <holzheu at linux.vnet.ibm.com> > > > > > > Currently only the address of the pre-allocated ELF header is passed with > > > the elfcorehdr= kernel parameter. In order to reserve memory for the header > > > in the 2nd kernel also the size is required. To pass the size with this > > > patch the syntax of the kernel parameter is extended as follows: > > > > > > elfcorehdr=[size[KMG]@]offset[KMG] > > > > > > This change is backward compatible because elfcorehdr=size is still allowed. > > > > Generally vmcore parses elfcorehdr to figure out the sizes. kexec-tools > > knows about it and relevant memory is excluded from second kernel's map > > with the help of memmap= command line option. > > > > Can you please mention that this is only s390 specific requirement as > > there are no memmap= equivalent options and somehow dump tools wants > > to know how big the elf header size is? > > I updated the description: > > Currently only the address of the pre-allocated ELF header is passed with > the elfcorehdr= kernel parameter. In order to reserve memory for the header > in the 2nd kernel also the size is required. Current kdump architecture > backends use different methods to do that, e.g. x86 uses the memmap= kernel > parameter. On s390 there is no easy way to transfer this information. > Therefore the elfcorehdr kernel parameter is extended to also pass the size. > This now can also be used as standard mechanism by all future kdump > architecture backends. > > The syntax of the kernel parameter is extended as follows: > > elfcorehdr=[size[KMG]@]offset[KMG] > > This change is backward compatible because elfcorehdr=size is still allowed. > > Ok? Yes, this one looks ok. Thanks Vivek
