• Vivek Goyal's avatar
    [PATCH] x86-64: build-time checking · 6a50a664
    Vivek Goyal authored
    o X86_64 kernel should run from 2MB aligned address for two reasons.
    	- Performance.
    	- For relocatable kernels, page tables are updated based on difference
    	  between compile time address and load time physical address.
    	  This difference should be multiple of 2MB as kernel text and data
    	  is mapped using 2MB pages and PMD should be pointing to a 2MB
    	  aligned address. Life is simpler if both compile time and load time
    	  kernel addresses are 2MB aligned.
    
    o Flag the error at compile time if one is trying to build a kernel which
      does not meet alignment restrictions.
    Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
    Signed-off-by: default avatarAndi Kleen <ak@suse.de>
    Cc: "Eric W. Biederman" <ebiederm@xmission.com>
    Cc: Andi Kleen <ak@suse.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    6a50a664
misc.c 9.5 KB