[PATCH] x86-64: Overlapping program headers in physical addr space fix

o A recent change to vmlinux.ld.S file broke kexec as now resulting vmlinux
  program headers are overlapping in physical address space.

o Now all the vsyscall related sections are placed after data and after
  that mostly init data sections are placed. To avoid physical overlap
  among phdrs, there are three possible solutions.
	- Place vsyscall sections also in data phdrs instead of user
	- move vsyscal sections after init data in bss.
	- create another phdrs say data.init and move all the sections
	  after vsyscall into this new phdr.

o This patch implements the third solution.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Magnus Damm <magnus@valinux.co.jp>
Cc: Andi Kleen <ak@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>

diff --git a/arch/x86_64/kernel/vmlinux.lds.S b/arch/x86_64/kernel/vmlinux.lds.S
index b9df2ab..1283614 100644 (file)
--- a/arch/x86_64/kernel/vmlinux.lds.S
+++ b/arch/x86_64/kernel/vmlinux.lds.S
@@ -17,6 +17,7 @@ PHDRS {
        text PT_LOAD FLAGS(5);  /* R_E */
        data PT_LOAD FLAGS(7);  /* RWE */
        user PT_LOAD FLAGS(7);  /* RWE */
+       data.init PT_LOAD FLAGS(7);     /* RWE */
        note PT_NOTE FLAGS(4);  /* R__ */
 }
 SECTIONS
@@ -131,7 +132,7 @@ SECTIONS
   . = ALIGN(8192);             /* init_task */
   .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
        *(.data.init_task)
-  } :data
+  }:data.init
 
   . = ALIGN(4096);
   .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {