Re: [PATCH RFC 5/5] arm64/speculation: Add support for 'cpu_spec_mitigations=' cmdline options

Will Deacon
2019-04-05T14:44:29Z

Hi Josh,

On Thu, Apr 04, 2019 at 11:44:15AM -0500, Josh Poimboeuf wrote:
> Configure arm64 runtime CPU speculation bug mitigations in accordance
> with the 'cpu_spec_mitigations=' cmdline options. This affects
> Meltdown and Speculative Store Bypass.
>
> The default behavior is unchanged.
>
> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
> ---
> Documentation/admin-guide/kernel-parameters.txt | 2 ++
> arch/arm64/kernel/cpu_errata.c | 4 ++++
> arch/arm64/kernel/cpufeature.c | 6 ++++++
> 3 files changed, 12 insertions(+)

Just wanted to make you aware that this is probably going to conflict badly
with some patches we have pending to hook up the sysfs entries:

http://lists.infradead.org/pipermail/linux-arm-kernel/2019-March/640326.html

That patch series isn't quite there yet, so I'm expecting a v7, but I think
it will change the shape of this patch quite a lot.

Will