Messages in this thread | | | Subject | Re: [PATCH v3 06/20] arm64: mm: Fix and re-enable ARM64_SW_TTBR0_PAN | From | Yisheng Xie <> | Date | Wed, 17 Jan 2018 10:58:23 +0800 |
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Hi Will,
On 2017/12/6 20:35, Will Deacon wrote: > config ARM64_SW_TTBR0_PAN > bool "Emulate Privileged Access Never using TTBR0_EL1 switching" > - depends on BROKEN # Temporary while switch_mm is reworked > help > Enabling this option prevents the kernel from accessing > user-space memory directly by pointing TTBR0_EL1 to a reserved
I have a question not related to this patch itself, but to ARM64_SW_TTBR0_PAN:
What does ARM64_SW_TTBR0_PAN used for? I means is hardware support PAN, do we still need SW_TTBR0_PAN?
And if the hardware do not support PAN, is SW_TTBR0_PAN is *must* option? or there maybe a security risk?
Thanks Yisheng Xie
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