Re: [PATCH 1/2] arm64: Ensure the instruction emulation is ready for userspace

From: Catalin Marinas
Date: Fri Oct 06 2017 - 11:36:01 EST


On Fri, Oct 06, 2017 at 02:16:52PM +0100, Suzuki K. Poulose wrote:
> We trap and emulate some instructions (e.g, mrs, deprecated instructions)
> for the userspace. However the handlers for these are registered as
> late_initcalls and the userspace could be up and running from the initramfs
> by that time (with populate_rootfs, which is a rootfs_initcall()). This
> could cause problems for the early applications ending up in failure
> like :
>
> [ 11.152061] modprobe[93]: undefined instruction: pc=0000ffff8ca48ff4
>
> This patch promotes the specific calls to core_initcalls, which are
> guaranteed to be completed before we hit userspace.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Dave Martin <dave.martin@xxxxxxx>
> Cc: Matthias Brugger <mbrugger@xxxxxxxx>
> Cc: James Morse <james.morse@xxxxxxx>
> Reported-by: Matwey V. Kornilov <matwey.kornilov@xxxxxxxxx>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

Both patches queued for 4.14. Thanks.

--
Catalin