From: Will Deacon <will@kernel.org>
To: Marc Zyngier <maz@kernel.org>
Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org, kernel-team@android.com
Subject: Re: [PATCH v2 0/2] KVM: arm64: Fix handling of S1PTW
Date: Fri, 18 Sep 2020 14:37:55 +0100 [thread overview]
Message-ID: <20200918133755.GD31232@willie-the-truck> (raw)
In-Reply-To: <20200915104218.1284701-1-maz@kernel.org>
On Tue, Sep 15, 2020 at 11:42:16AM +0100, Marc Zyngier wrote:
> I recently managed to trigger an interesting failure mode, where a
> guest would be stuck on an instruction abort due to a permission
> fault. Interestingly enough, this IABT had S1PTW set in the ESR,
> indicating that it was trying to *write* to the PT. We fix it by
> adding the execute permission (it's an IABT, after all...), and going
> nowhere fast.
>
> Note that it can only happen on a system that can perform automatic
> updates of the page table flags.
>
> This small series fixes the issue by revamping the S1PTW handling in
> the context of execution faults. The first patch fixes the bug, and is
> definitely a stable candidate. The second patch is merely a cleanup,
> which can wait.
>
> Tested on an A55-based board.
>
> * From v1:
> - Rename kvm_vcpu_dabt_iss1tw() to kvm_vcpu_abt_iss1tw()
> - Don't overload kvm_vcpu_trap_is_iabt()
> - Introduce kvm_vcpu_trap_is_exec_fault()
For both patches:
Reviewed-by: Will Deacon <will@kernel.org>
Cheers,
Will
WARNING: multiple messages have this Message-ID (diff)
From: Will Deacon <will@kernel.org>
To: Marc Zyngier <maz@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org, kernel-team@android.com,
kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Subject: Re: [PATCH v2 0/2] KVM: arm64: Fix handling of S1PTW
Date: Fri, 18 Sep 2020 14:37:55 +0100 [thread overview]
Message-ID: <20200918133755.GD31232@willie-the-truck> (raw)
In-Reply-To: <20200915104218.1284701-1-maz@kernel.org>
On Tue, Sep 15, 2020 at 11:42:16AM +0100, Marc Zyngier wrote:
> I recently managed to trigger an interesting failure mode, where a
> guest would be stuck on an instruction abort due to a permission
> fault. Interestingly enough, this IABT had S1PTW set in the ESR,
> indicating that it was trying to *write* to the PT. We fix it by
> adding the execute permission (it's an IABT, after all...), and going
> nowhere fast.
>
> Note that it can only happen on a system that can perform automatic
> updates of the page table flags.
>
> This small series fixes the issue by revamping the S1PTW handling in
> the context of execution faults. The first patch fixes the bug, and is
> definitely a stable candidate. The second patch is merely a cleanup,
> which can wait.
>
> Tested on an A55-based board.
>
> * From v1:
> - Rename kvm_vcpu_dabt_iss1tw() to kvm_vcpu_abt_iss1tw()
> - Don't overload kvm_vcpu_trap_is_iabt()
> - Introduce kvm_vcpu_trap_is_exec_fault()
For both patches:
Reviewed-by: Will Deacon <will@kernel.org>
Cheers,
Will
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
WARNING: multiple messages have this Message-ID (diff)
From: Will Deacon <will@kernel.org>
To: Marc Zyngier <maz@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org, kernel-team@android.com,
kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Subject: Re: [PATCH v2 0/2] KVM: arm64: Fix handling of S1PTW
Date: Fri, 18 Sep 2020 14:37:55 +0100 [thread overview]
Message-ID: <20200918133755.GD31232@willie-the-truck> (raw)
In-Reply-To: <20200915104218.1284701-1-maz@kernel.org>
On Tue, Sep 15, 2020 at 11:42:16AM +0100, Marc Zyngier wrote:
> I recently managed to trigger an interesting failure mode, where a
> guest would be stuck on an instruction abort due to a permission
> fault. Interestingly enough, this IABT had S1PTW set in the ESR,
> indicating that it was trying to *write* to the PT. We fix it by
> adding the execute permission (it's an IABT, after all...), and going
> nowhere fast.
>
> Note that it can only happen on a system that can perform automatic
> updates of the page table flags.
>
> This small series fixes the issue by revamping the S1PTW handling in
> the context of execution faults. The first patch fixes the bug, and is
> definitely a stable candidate. The second patch is merely a cleanup,
> which can wait.
>
> Tested on an A55-based board.
>
> * From v1:
> - Rename kvm_vcpu_dabt_iss1tw() to kvm_vcpu_abt_iss1tw()
> - Don't overload kvm_vcpu_trap_is_iabt()
> - Introduce kvm_vcpu_trap_is_exec_fault()
For both patches:
Reviewed-by: Will Deacon <will@kernel.org>
Cheers,
Will
_______________________________________________
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:[~2020-09-18 13:38 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-15 10:42 [PATCH v2 0/2] KVM: arm64: Fix handling of S1PTW Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-15 10:42 ` [PATCH v2 1/2] KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetch Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-21 12:54 ` Sasha Levin
2020-09-21 12:54 ` Sasha Levin
2020-09-15 10:42 ` [PATCH v2 2/2] KVM: arm64: Remove S1PTW check from kvm_vcpu_dabt_iswrite() Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-15 10:42 ` Marc Zyngier
2020-09-18 13:37 ` Will Deacon [this message]
2020-09-18 13:37 ` [PATCH v2 0/2] KVM: arm64: Fix handling of S1PTW Will Deacon
2020-09-18 13:37 ` Will Deacon
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=20200918133755.GD31232@willie-the-truck \
--to=will@kernel.org \
--cc=kernel-team@android.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=maz@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.