From: Marc Zyngier <maz@kernel.org>
To: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, stable@vger.kernel.org,
pbonzini@redhat.com, linuxarm@huawei.com
Subject: Re: [PATCH for-stable-5.10 2/2] KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility
Date: Thu, 25 Mar 2021 09:33:17 +0000 [thread overview]
Message-ID: <9850fc39c1c80840ea77eba60ee5e663@kernel.org> (raw)
In-Reply-To: <20210325091424.26348-3-shameerali.kolothum.thodi@huawei.com>
On 2021-03-25 09:14, Shameer Kolothum wrote:
> From: Marc Zyngier <maz@kernel.org>
>
> commit 9739f6ef053f104a997165701c6e15582c4307ee upstream.
>
> It looks like we have broken firmware out there that wrongly advertises
> a GICv2 compatibility interface, despite the CPUs not being able to
> deal
> with it.
>
> To work around this, check that the CPU initialising KVM is actually
> able
> to switch to MMIO instead of system registers, and use that as a
> precondition to enable GICv2 compatibility in KVM.
>
> Note that the detection happens on a single CPU. If the firmware is
> lying *and* that the CPUs are asymetric, all hope is lost anyway.
>
> Cc: stable@vger.kernel.org #5.10
> Reported-by: Shameerali Kolothum Thodi
> <shameerali.kolothum.thodi@huawei.com>
> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> Message-Id: <20210305185254.3730990-8-maz@kernel.org>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Please hold on on that.
This patch causes a regression, and needs a fix that is currently queued
for 5.12 [1]. Once this hits upstream, please add the fix to the series
and post it as a whole.
Thanks,
M.
[1] https://lore.kernel.org/r/20210323162301.2049595-1-maz@kernel.org
--
Jazz is not dead. It just smells funny...
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-03-25 9:40 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-25 9:14 [PATCH for-stable-5.10 0/2] Backport for- Work around firmware wrongly advertising GICv2 compatibility Shameer Kolothum
2021-03-25 9:14 ` [PATCH for-stable-5.10 1/2] KVM: arm64: Rename __vgic_v3_get_ich_vtr_el2() to __vgic_v3_get_gic_config() Shameer Kolothum
2021-03-25 9:14 ` [PATCH for-stable-5.10 2/2] KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility Shameer Kolothum
2021-03-25 9:33 ` Marc Zyngier [this message]
2021-03-25 9:37 ` Shameerali Kolothum Thodi
2021-03-25 9:54 ` Marc Zyngier
2021-03-25 11:38 ` Greg KH
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=9850fc39c1c80840ea77eba60ee5e663@kernel.org \
--to=maz@kernel.org \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linuxarm@huawei.com \
--cc=pbonzini@redhat.com \
--cc=shameerali.kolothum.thodi@huawei.com \
--cc=stable@vger.kernel.org \
/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).