[PATCH 3/4] KVM: arm64: Use sanitized values in __check_override in nVHE

From: Quentin Perret
Date: Wed Feb 01 2023 - 05:39:06 EST


The nVHE EL2 code has access to sanitized values of certain idregs, so
use them directly from __check_override instead of the *_override
variants.

Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
---
arch/arm64/include/asm/el2_setup.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index fb7d04b81033..1cc29960fcdb 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -196,6 +196,7 @@
__init_el2_nvhe_prepare_eret
.endm

+#ifndef __KVM_NVHE_HYPERVISOR__
// This will clobber tmp1 and tmp2, and expect tmp1 to contain
// the id register value as read from the HW
.macro __check_override idreg, fld, width, pass, fail, tmp1, tmp2
@@ -219,6 +220,19 @@
mrs \tmp1, \idreg\()_el1
__check_override \idreg \fld 4 \pass \fail \tmp1 \tmp2
.endm
+#else
+// This will clobber tmp
+.macro __check_override idreg, fld, width, pass, fail, tmp, ignore
+ ldr_l \tmp, \idreg\()_el1_sys_val
+ ubfx \tmp, \tmp, #\fld, #\width
+ cbnz \tmp, \pass
+ b \fail
+.endm
+
+.macro check_override idreg, fld, pass, fail, tmp, ignore
+ __check_override \idreg \fld 4 \pass \fail \tmp \ignore
+.endm
+#endif

.macro finalise_el2_state
check_override id_aa64pfr0, ID_AA64PFR0_EL1_SVE_SHIFT, .Linit_sve_\@, .Lskip_sve_\@, x1, x2
--
2.39.1.456.gfc5497dd1b-goog