On Wed, Sep 14, 2011 at 10:58:28AM +0200, Michael Holzheu wrote: > Hello Andrew, > > On Tue, 2011-09-13 at 14:52 -0700, Andrew Morton wrote: > > On Tue, 13 Sep 2011 15:26:37 +0200 > > Michael Holzheu <holzheu at linux.vnet.ibm.com> wrote: > > [snip] > > > > --- a/arch/s390/include/asm/kexec.h > > > +++ b/arch/s390/include/asm/kexec.h > > > @@ -36,6 +36,9 @@ > > > /* Allocate one page for the pdp and the second for the code */ > > > #define KEXEC_CONTROL_PAGE_SIZE 4096 > > > > > > +/* Alignment of crashkernel memory */ > > > +#define KEXEC_CRASH_MEM_ALIGN HPAGE_SIZE > > > > Why not make this unconditional, for all architectures which support > > hugepages? ie: > > > > #ifdef HPAGE_SIZE > > #define KEXEC_CRASH_MEM_ALIGN HPAGE_SIZE > > #else > > #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE > > #endif > > > in include/linux/kexec.h? > > > > IOW, what are the compromises here? > > If we would do it that way, crashkernel memory on architectures that > support large pages but do not support unmapping of crashkernel memory > would always be aligned to HPAGE_SIZE. But only PAGE_SIZE alignment > would be necessary in that case. > > If that is acceptable I have no problem to define that unconditional for > all architectures. Vivek what do you think? As PAGE_SIZE alignment is sufficient for rest of the architecture, I am fine with keeping it in arch dependent files. Thanks Vivek
