All of lore.kernel.org
 help / color / mirror / Atom feed
From: Will Deacon <will@kernel.org>
To: kvmarm@lists.cs.columbia.edu
Cc: kernel-team@android.com, Marc Zyngier <maz@kernel.org>,
	Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/7] KVM: arm64: Handle data and instruction external aborts the same way
Date: Fri, 24 Jul 2020 15:35:02 +0100	[thread overview]
Message-ID: <20200724143506.17772-4-will@kernel.org> (raw)
In-Reply-To: <20200724143506.17772-1-will@kernel.org>

If the guest generates a synchronous external abort which is not handled
by the host, we inject it back into the guest as a virtual SError, but
only if the original fault was reported on the data side. Instruction
faults are reported as "Unsupported FSC", causing the vCPU run loop to
bail with -EFAULT.

Although synchronous external aborts from a guest are pretty unusual,
treat them the same regardless of whether they are taken as data or
instruction aborts by EL2.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kvm/mmu.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 660a83a172e4..ae17a99243e2 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -2079,13 +2079,10 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		 * For RAS the host kernel may handle this abort.
 		 * There is no need to pass the error into the guest.
 		 */
-		if (!kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
-			return 1;
-
-		if (unlikely(!is_iabt)) {
+		if (kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
 			kvm_inject_vabt(vcpu);
-			return 1;
-		}
+
+		return 1;
 	}
 
 	trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_hsr(vcpu),
-- 
2.28.0.rc0.142.g3c755180ce-goog

_______________________________________________
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: kvmarm@lists.cs.columbia.edu
Cc: Quentin Perret <qperret@google.com>,
	kernel-team@android.com, Suzuki Poulose <suzuki.poulose@arm.com>,
	James Morse <james.morse@arm.com>, Marc Zyngier <maz@kernel.org>,
	Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/7] KVM: arm64: Handle data and instruction external aborts the same way
Date: Fri, 24 Jul 2020 15:35:02 +0100	[thread overview]
Message-ID: <20200724143506.17772-4-will@kernel.org> (raw)
In-Reply-To: <20200724143506.17772-1-will@kernel.org>

If the guest generates a synchronous external abort which is not handled
by the host, we inject it back into the guest as a virtual SError, but
only if the original fault was reported on the data side. Instruction
faults are reported as "Unsupported FSC", causing the vCPU run loop to
bail with -EFAULT.

Although synchronous external aborts from a guest are pretty unusual,
treat them the same regardless of whether they are taken as data or
instruction aborts by EL2.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kvm/mmu.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 660a83a172e4..ae17a99243e2 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -2079,13 +2079,10 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		 * For RAS the host kernel may handle this abort.
 		 * There is no need to pass the error into the guest.
 		 */
-		if (!kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
-			return 1;
-
-		if (unlikely(!is_iabt)) {
+		if (kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
 			kvm_inject_vabt(vcpu);
-			return 1;
-		}
+
+		return 1;
 	}
 
 	trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_hsr(vcpu),
-- 
2.28.0.rc0.142.g3c755180ce-goog


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

  parent reply	other threads:[~2020-07-24 14:35 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-24 14:34 [PATCH 0/7] KVM: arm64: Fixes to early stage-2 fault handling Will Deacon
2020-07-24 14:34 ` Will Deacon
2020-07-24 14:35 ` [PATCH 1/7] KVM: arm64: Update comment when skipping guest MMIO access instruction Will Deacon
2020-07-24 14:35   ` Will Deacon
2020-07-26 11:08   ` Marc Zyngier
2020-07-26 11:08     ` Marc Zyngier
2020-07-27 10:30     ` Will Deacon
2020-07-27 10:30       ` Will Deacon
2020-07-24 14:35 ` [PATCH 2/7] KVM: arm64: Rename kvm_vcpu_dabt_isextabt() Will Deacon
2020-07-24 14:35   ` Will Deacon
2020-07-26 11:15   ` Marc Zyngier
2020-07-26 11:15     ` Marc Zyngier
2020-07-27 10:30     ` Will Deacon
2020-07-27 10:30       ` Will Deacon
2020-07-24 14:35 ` Will Deacon [this message]
2020-07-24 14:35   ` [PATCH 3/7] KVM: arm64: Handle data and instruction external aborts the same way Will Deacon
2020-07-24 14:35 ` [PATCH 4/7] KVM: arm64: Remove useless local variable Will Deacon
2020-07-24 14:35   ` Will Deacon
2020-07-24 14:35 ` [PATCH 5/7] KVM: arm64: Move 'invalid syndrome' logic out of io_mem_abort() Will Deacon
2020-07-24 14:35   ` Will Deacon
2020-07-26 11:55   ` Marc Zyngier
2020-07-26 11:55     ` Marc Zyngier
2020-07-27 10:31     ` Will Deacon
2020-07-27 10:31       ` Will Deacon
2020-07-24 14:35 ` [PATCH 6/7] KVM: arm64: Handle stage-2 faults on stage-1 page-table walks earlier Will Deacon
2020-07-24 14:35   ` Will Deacon
2020-07-26 13:38   ` Marc Zyngier
2020-07-26 13:38     ` Marc Zyngier
2020-07-27 10:29     ` Will Deacon
2020-07-27 10:29       ` Will Deacon
2020-07-24 14:35 ` [PATCH 7/7] KVM: arm64: Separate write faults on read-only memslots from MMIO Will Deacon
2020-07-24 14:35   ` 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=20200724143506.17772-4-will@kernel.org \
    --to=will@kernel.org \
    --cc=kernel-team@android.com \
    --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.