From: Thomas Garnier <thgarnie@google.com>
Subject: Re: [RFC v2 13/23] x86/power/64: Adapt assembly for PIE support
Date: Fri, 11 Aug 2017 08:09:41 -0700
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 <20170811123618.GC16126@amd>
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Cc: Herbert Xu <herbert@gondor.apana.org.au>, "David S . Miller" <davem@davemloft.net>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>,
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To: Pavel Machek <pavel@ucw.cz>
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On Fri, Aug 11, 2017 at 5:36 AM, Pavel Machek <pavel@ucw.cz> wrote:
> On Thu 2017-08-10 10:26:05, Thomas Garnier wrote:
>> 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 <thgarnie@google.com>
>
> Acked-by: Pavel Machek <pavel@ucw.cz>

Thanks Pavel!

>
>> --- 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
>
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html



-- 
Thomas