[patch v2 03/10] kdump: Add size to elfcorehdr kernel parameter

Michael Holzheu holzheu at linux.vnet.ibm.com
Wed Aug 3 06:40:44 EDT 2011


Hello Vivek,

On Tue, 2011-08-02 at 14:55 -0400, Vivek Goyal wrote:
> On Tue, Aug 02, 2011 at 11:08:07AM +0200, Michael Holzheu wrote:
> > Hello Vivek,
> > 
> > > 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.

With that description change: Do I get an "Acked-by" for this patch from
you?

Michael




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