From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoffer Dall <christoffer.dall@linaro.org>
Subject: Re: [PATCH 4/7] KVM: arm64: guest debug, add SW break point support
Date: Sat, 29 Nov 2014 17:21:46 +0100
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Cc: Alex =?iso-8859-1?Q?Benn=E9e?= <alex.bennee@linaro.org>,
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To: Andrew Jones <drjones@redhat.com>
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On Wed, Nov 26, 2014 at 05:07:20PM +0100, Andrew Jones wrote:
> On Tue, Nov 25, 2014 at 04:10:02PM +0000, Alex Benn=E9e wrote:
> > This adds support for SW breakpoints inserted by userspace.
> >=20
> > First we need to trap all BKPT exceptions in the hypervisor (ELS). =
This
> > in controlled through the MDCR_EL2 register. I've added a new field=
 to
> > the vcpu structure to hold this value. There should be scope to
> > rationlise this with the VCPU_DEBUG_FLAGS/KVM_ARM64_DEBUG_DIRTY_SHI=
=46T
> > manipulation in later patches.
>=20
> I think we should start using the new mdcr_el2 field everywhere we pl=
an
> to within the same series that it is introduced. Otherwise it's hard
> to tell if we need an mdcr_el2 field, or if a more generic field woul=
d
> suffice. We can always translate bits of a more generic field to
> mdcr_el2 bits when necessary, but not the reverse.
>=20
Agreed, this is getting messy already with this patch.

-Christoffer