All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	kvmarm@lists.cs.columbia.edu
Cc: James Morse <james.morse@arm.com>,
	Julien Thierry <julien.thierry.kdev@gmail.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Andrew Scull <ascull@google.com>,
	Dave Martin <Dave.Martin@arm.com>,
	kernel-team@android.com
Subject: [PATCH v2 4/5] KVM: arm64: Check HCR_EL2 instead of shadow copy to swap PtrAuth registers
Date: Mon, 22 Jun 2020 09:06:42 +0100	[thread overview]
Message-ID: <20200622080643.171651-5-maz@kernel.org> (raw)
In-Reply-To: <20200622080643.171651-1-maz@kernel.org>

When save/restoring PtrAuth registers between host and guest, it is
pretty useless to fetch the in-memory state, while we have the right
state in the HCR_EL2 system register. Use that instead.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_ptrauth.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h
index 6301813dcace..f1830173fa9e 100644
--- a/arch/arm64/include/asm/kvm_ptrauth.h
+++ b/arch/arm64/include/asm/kvm_ptrauth.h
@@ -74,7 +74,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF
 	b	1001f
 alternative_else_nop_endif
 1000:
-	ldr	\reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)]
+	mrs	\reg1, hcr_el2
 	and	\reg1, \reg1, #(HCR_API | HCR_APK)
 	cbz	\reg1, 1001f
 	add	\reg1, \g_ctxt, #CPU_APIAKEYLO_EL1
@@ -90,7 +90,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF
 	b	2001f
 alternative_else_nop_endif
 2000:
-	ldr	\reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)]
+	mrs	\reg1, hcr_el2
 	and	\reg1, \reg1, #(HCR_API | HCR_APK)
 	cbz	\reg1, 2001f
 	add	\reg1, \g_ctxt, #CPU_APIAKEYLO_EL1
-- 
2.27.0


WARNING: multiple messages have this Message-ID (diff)
From: Marc Zyngier <maz@kernel.org>
To: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	kvmarm@lists.cs.columbia.edu
Cc: kernel-team@android.com, Dave Martin <Dave.Martin@arm.com>
Subject: [PATCH v2 4/5] KVM: arm64: Check HCR_EL2 instead of shadow copy to swap PtrAuth registers
Date: Mon, 22 Jun 2020 09:06:42 +0100	[thread overview]
Message-ID: <20200622080643.171651-5-maz@kernel.org> (raw)
In-Reply-To: <20200622080643.171651-1-maz@kernel.org>

When save/restoring PtrAuth registers between host and guest, it is
pretty useless to fetch the in-memory state, while we have the right
state in the HCR_EL2 system register. Use that instead.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_ptrauth.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h
index 6301813dcace..f1830173fa9e 100644
--- a/arch/arm64/include/asm/kvm_ptrauth.h
+++ b/arch/arm64/include/asm/kvm_ptrauth.h
@@ -74,7 +74,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF
 	b	1001f
 alternative_else_nop_endif
 1000:
-	ldr	\reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)]
+	mrs	\reg1, hcr_el2
 	and	\reg1, \reg1, #(HCR_API | HCR_APK)
 	cbz	\reg1, 1001f
 	add	\reg1, \g_ctxt, #CPU_APIAKEYLO_EL1
@@ -90,7 +90,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF
 	b	2001f
 alternative_else_nop_endif
 2000:
-	ldr	\reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)]
+	mrs	\reg1, hcr_el2
 	and	\reg1, \reg1, #(HCR_API | HCR_APK)
 	cbz	\reg1, 2001f
 	add	\reg1, \g_ctxt, #CPU_APIAKEYLO_EL1
-- 
2.27.0

_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm

  parent reply	other threads:[~2020-06-22  8:07 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-22  8:06 [PATCH v2 0/5] KVM/arm64: Enable PtrAuth on non-VHE KVM Marc Zyngier
2020-06-22  8:06 ` Marc Zyngier
2020-06-22  8:06 ` [PATCH v2 1/5] KVM: arm64: Enable Address Authentication at EL2 if available Marc Zyngier
2020-06-22  8:06   ` Marc Zyngier
2020-06-22  9:04   ` Mark Rutland
2020-06-22  9:04     ` Mark Rutland
2020-06-22  8:06 ` [PATCH v2 2/5] KVM: arm64: Allow ARM64_PTR_AUTH when ARM64_VHE=n Marc Zyngier
2020-06-22  8:06   ` Marc Zyngier
2020-06-22  8:06 ` [PATCH v2 3/5] KVM: arm64: Allow PtrAuth to be enabled from userspace on non-VHE systems Marc Zyngier
2020-06-22  8:06   ` Marc Zyngier
2020-06-22  8:06 ` Marc Zyngier [this message]
2020-06-22  8:06   ` [PATCH v2 4/5] KVM: arm64: Check HCR_EL2 instead of shadow copy to swap PtrAuth registers Marc Zyngier
2020-06-22  8:06 ` [PATCH v2 5/5] KVM: arm64: Simplify PtrAuth alternative patching Marc Zyngier
2020-06-22  8:06   ` Marc Zyngier
2020-06-22  9:15   ` Mark Rutland
2020-06-22  9:15     ` Mark Rutland
2020-06-22 10:25     ` Marc Zyngier
2020-06-22 10:25       ` Marc Zyngier
2020-06-22 10:31       ` Mark Rutland
2020-06-22 10:31         ` Mark Rutland
2020-06-22 10:39     ` Andrew Scull
2020-06-22 10:39       ` Andrew Scull
2020-06-22 10:43       ` Andrew Scull
2020-06-22 10:43         ` Andrew Scull

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=20200622080643.171651-5-maz@kernel.org \
    --to=maz@kernel.org \
    --cc=Dave.Martin@arm.com \
    --cc=ascull@google.com \
    --cc=james.morse@arm.com \
    --cc=julien.thierry.kdev@gmail.com \
    --cc=kernel-team@android.com \
    --cc=kvm@vger.kernel.org \
    --cc=kvmarm@lists.cs.columbia.edu \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=mark.rutland@arm.com \
    --cc=suzuki.poulose@arm.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 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.