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

Catalin Marinas catalin.marinas at arm.com
Fri Oct 6 08:35:51 PDT 2017


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 at vger.kernel.org
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Dave Martin <dave.martin at arm.com>
> Cc: Matthias Brugger <mbrugger at suse.com>
> Cc: James Morse <james.morse at arm.com>
> Reported-by: Matwey V. Kornilov <matwey.kornilov at gmail.com>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>

Both patches queued for 4.14. Thanks.

-- 
Catalin



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