Re: ACPI sleep issues (trap 4)

[Joerg Sonnenberger <joerg%bec.de@localhost>]

On Thu, Sep 21, 2017 at 07:45:11PM +0200, Maxime Villard wrote:
> Le 21/09/2017 à 18:07, Joerg Sonnenberger a écrit :
> > On Thu, Sep 21, 2017 at 12:14:19PM +0200, Maxime Villard wrote:
> > > I wouldn't expect ACPI sleep to be reliable, there are several sets of
> > > registers that are not saved & restored.
> > 
> > FPU state is saved before, the generic purpose registers are saved as
> > required by the ABI. Can you be more precise in what exactly needs to be
> > saved?
> 
> dbregs and MSRs (PMCs, PAT, etc). Also not sure the FPU state is saved
> correctly (my xcr0 change needs to be tested).

Neither dbregs nor PMCs are relevant from a reliability perspective.
Other MSRs are recent regressions. FPU state saving definitely used to
work reliably as well.

Joerg