Re: [RFC v2 2/7] arm: Use generic VDSO unmap and remap

From: Russell King - ARM Linux
Date: Tue Nov 01 2016 - 13:21:31 EST


You know, on its own, this patch is totally meaningless. Sorry, there's
nothing more I can say about this.

On Tue, Nov 01, 2016 at 11:10:56AM -0600, Christopher Covington wrote:
> Checkpoint/Restore In Userspace (CRIU) needs to be able to unmap and remap
> the VDSO to successfully checkpoint and restore applications in the face of
> changing VDSO addresses due to Address Space Layout Randomization (ASLR,
> randmaps). Previously, this was implemented in architecture-specific code
> for PowerPC and x86. However, a generic version based on Laurent Dufour's
> PowerPC implementation is now available, so begin using it on ARM.
>
> Signed-off-by: Christopher Covington <cov@xxxxxxxxxxxxxx>
> ---
> arch/arm/mm/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
> index c1799dd..1d3312b 100644
> --- a/arch/arm/mm/Kconfig
> +++ b/arch/arm/mm/Kconfig
> @@ -845,6 +845,7 @@ config VDSO
> depends on AEABI && MMU && CPU_V7
> default y if ARM_ARCH_TIMER
> select GENERIC_TIME_VSYSCALL
> + select GENERIC_VDSO
> help
> Place in the process address space an ELF shared object
> providing fast implementations of gettimeofday and
> --
> Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the
> Code Aurora Forum, a Linux Foundation Collaborative Project.
>

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