linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Oliver Upton <oliver.upton@linux.dev>
To: Marc Zyngier <maz@kernel.org>
Cc: Miguel Luis <miguel.luis@oracle.com>,
	"kvmarm@lists.linux.dev" <kvmarm@lists.linux.dev>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	Eric Auger <eric.auger@redhat.com>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Zenghui Yu <yuzenghui@huawei.com>
Subject: Re: [PATCH 5/5] KVM: arm64: Handle AArch32 SPSR_{irq,abt,und,fiq} as RAZ/WI
Date: Tue, 24 Oct 2023 23:04:27 +0000	[thread overview]
Message-ID: <ZThNeyX0muR5yvey@linux.dev> (raw)
In-Reply-To: <ZThINaAfNDNrIAqI@linux.dev>

On Tue, Oct 24, 2023 at 10:41:57PM +0000, Oliver Upton wrote:
> On Tue, Oct 24, 2023 at 06:25:33PM +0100, Marc Zyngier wrote:
> > On Mon, 23 Oct 2023 19:55:10 +0100, Miguel Luis <miguel.luis@oracle.com> wrote:
> > > Also, could you please explain what is happening at PSTATE.EL == EL1
> > > and if EL2Enabled() && HCR_EL2.NV == ‘1’  ?
> > 
> > We directly take the trap and not forward it. This isn't exactly the
> > letter of the architecture, but at the same time, treating these
> > registers as RAZ/WI is the only valid implementation. I don't
> > immediately see a problem with taking this shortcut.
> 
> Ugh, that's annoying. The other EL2 views of AArch32 state UNDEF if EL1
> doesn't implement AArch32. It'd be nice to get a relaxation in the
> architecture to allow an UNDEF here.

Correction (I wasn't thinking): RES0 behavior should be invariant, much
like the UNDEF behavior of the other AA32-specific registers.

-- 
Thanks,
Oliver

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2023-10-24 23:05 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-23  9:54 [PATCH 0/5] KVM: arm64: NV trap forwarding fixes Marc Zyngier
2023-10-23  9:54 ` [PATCH 1/5] arm64: Add missing _EL12 encodings Marc Zyngier
2023-10-23  9:54 ` [PATCH 2/5] arm64: Add missing _EL2 encodings Marc Zyngier
2023-10-23  9:54 ` [PATCH 3/5] KVM: arm64: Refine _EL2 system register list that require trap reinjection Marc Zyngier
2023-10-23  9:54 ` [PATCH 4/5] KVM: arm64: Do not let a L1 hypervisor access the *32_EL2 sysregs Marc Zyngier
2023-10-23  9:54 ` [PATCH 5/5] KVM: arm64: Handle AArch32 SPSR_{irq,abt,und,fiq} as RAZ/WI Marc Zyngier
2023-10-23 18:55   ` Miguel Luis
2023-10-24 17:25     ` Marc Zyngier
2023-10-24 22:41       ` Oliver Upton
2023-10-24 23:04         ` Oliver Upton [this message]
2023-10-25  8:28           ` Marc Zyngier
2023-10-25  8:46             ` Oliver Upton
2023-10-25  8:49               ` Marc Zyngier
2023-10-25 10:44       ` Miguel Luis
2023-10-25  6:40 ` [PATCH 0/5] KVM: arm64: NV trap forwarding fixes Oliver Upton

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=ZThNeyX0muR5yvey@linux.dev \
    --to=oliver.upton@linux.dev \
    --cc=eric.auger@redhat.com \
    --cc=james.morse@arm.com \
    --cc=kvm@vger.kernel.org \
    --cc=kvmarm@lists.linux.dev \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=maz@kernel.org \
    --cc=miguel.luis@oracle.com \
    --cc=suzuki.poulose@arm.com \
    --cc=yuzenghui@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).