Re: [Resend][PATCH] x86/power/64: Always create temporary identity mapping correctly

From: Jiri Kosina
Date: Tue Aug 09 2016 - 16:02:33 EST


On Tue, 9 Aug 2016, Rafael J. Wysocki wrote:

> I have a murky suspicion, but it is really weird. Namely, what if
> restore_jump_address in set_up_temporary_text_mapping() happens to be
> covered by the restore kernel's identity mapping? Then, the image
> kernel's entry point may get overwritten by something else in
> core_restore_code().

So this made me to actually test a scenario where I'd suspend a kernel
that's known-broken (i.e. contains 021182e52fe), and then have it resumed
by a kernel that has 021182e52fe reverted. It resumed successfully.

Just a datapoint.

--
Jiri Kosina
SUSE Labs