Re: [RFC v2 13/23] x86/power/64: Adapt assembly for PIE support

On Fri, Aug 11, 2017 at 5:36 AM, Pavel Machek [off-list ref] wrote:

On Thu 2017-08-10 10:26:05, Thomas Garnier wrote:

quoted

Change the assembly code to use only relative references of symbols for the
kernel to be PIE compatible.

Position Independent Executable (PIE) support will allow to extended the
KASLR randomization range below the -2G memory limit.

Signed-off-by: Thomas Garnier <redacted>

Acked-by: Pavel Machek <redacted>

Thanks Pavel!

quoted

--- a/arch/x86/power/hibernate_asm_64.S
+++ b/arch/x86/power/hibernate_asm_64.S

@@ -24,7 +24,7 @@
 #include <asm/frame.h>

 ENTRY(swsusp_arch_suspend)
-     movq    $saved_context, %rax
+     leaq    saved_context(%rip), %rax
      movq    %rsp, pt_regs_sp(%rax)
      movq    %rbp, pt_regs_bp(%rax)
      movq    %rsi, pt_regs_si(%rax)

@@ -115,7 +115,7 @@ ENTRY(restore_registers)
      movq    %rax, %cr4;  # turn PGE back on

      /* We don't restore %rax, it must be 0 anyway */
-     movq    $saved_context, %rax
+     leaq    saved_context(%rip), %rax
      movq    pt_regs_sp(%rax), %rsp
      movq    pt_regs_bp(%rax), %rbp
      movq    pt_regs_si(%rax), %rsi

--
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-- 
Thomas