linux-kernel - Re: [PATCH v4 15/22] arm64: capabilities: Change scope of VHE to Boot CPU feature

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180321151837.GC16308@e103592.cambridge.arm.com>
Date:   Wed, 21 Mar 2018 15:18:37 +0000
From:   Dave Martin <Dave.Martin@....com>
To:     Suzuki K Poulose <suzuki.poulose@....com>
Cc:     linux-arm-kernel@...ts.infradead.org, mark.rutland@....com,
        ckadabi@...eaurora.org, ard.biesheuvel@...aro.org,
        marc.zyngier@....com, catalin.marinas@....com, will.deacon@....com,
        linux-kernel@...r.kernel.org, jnair@...iumnetworks.com,
        robin.murphy@....com, shankerd@...eaurora.org
Subject: Re: [PATCH v4 15/22] arm64: capabilities: Change scope of VHE to
 Boot CPU feature

On Tue, Mar 13, 2018 at 11:51:13AM +0000, Suzuki K Poulose wrote:
> We expect all CPUs to be running at the same EL inside the kernel
> with or without VHE enabled and we have strict checks to ensure
> that any mismatch triggers a kernel panic. If VHE is enabled,
> we use the feature based on the boot CPU and all other CPUs
> should follow. This makes it a perfect candidate for a cpability

Nit: capability (not worth fixing unless you respin for some other
reason though.)

> based on the boot CPU,  which should be matched by all the CPUs
> (both when is ON and OFF). This saves us some not-so-pretty
> hooks and special code, just for verifying the conflict.
> 
> The patch also makes the VHE capability entry depend on
> CONFIG_ARM64_VHE.
> 
> Cc: Marc Zyngier <marc.zyngier@....com>
> Cc: Dave Martin <dave.martin@....com>
> Cc: Will Deacon <will.deacon@....com>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@....com>

Reviewed-by: Dave Martin <Dave.Martin@....com>

[...]

Cheers
---Dave