Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
KVM: arm64: Extend unified RESx handling to runtime sanitisation
Add a new helper to retrieve the RESx values for a given system
register, and use it for the runtime sanitisation.
This results in slightly better code generation for a fairly hot
path in the hypervisor, and additionally covers all sanitised
registers in all conditions, not just the VNCR-based ones.
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260202184329.2724080-6-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
+20
-18
+15
arch/arm64/include/asm/kvm_host.h
+15
arch/arm64/include/asm/kvm_host.h
···
635
635
struct resx mask[NR_SYS_REGS - __SANITISED_REG_START__];
636
636
};
637
637
638
+
static inline struct resx __kvm_get_sysreg_resx(struct kvm_arch *arch,
639
+
enum vcpu_sysreg sr)
640
+
{
641
+
struct kvm_sysreg_masks *masks;
642
+
643
+
masks = arch->sysreg_masks;
644
+
if (likely(masks &&
645
+
sr >= __SANITISED_REG_START__ && sr < NR_SYS_REGS))
646
+
return masks->mask[sr - __SANITISED_REG_START__];
647
+
648
+
return (struct resx){};
649
+
}
650
+
651
+
#define kvm_get_sysreg_resx(k, sr) __kvm_get_sysreg_resx(&(k)->arch, (sr))
652
+
638
653
static inline void __kvm_set_sysreg_resx(struct kvm_arch *arch,
639
654
enum vcpu_sysreg sr, struct resx resx)
640
655
{
+1
-9
arch/arm64/kvm/emulate-nested.c
+1
-9
arch/arm64/kvm/emulate-nested.c
···
2427
2427
2428
2428
static u64 kvm_get_sysreg_res0(struct kvm *kvm, enum vcpu_sysreg sr)
2429
2429
{
2430
-
struct kvm_sysreg_masks *masks;
2431
-
2432
-
/* Only handle the VNCR-backed regs for now */
2433
-
if (sr < __VNCR_START__)
2434
-
return 0;
2435
-
2436
-
masks = kvm->arch.sysreg_masks;
2437
-
2438
-
return masks->mask[sr - __SANITISED_REG_START__].res0;
2430
+
return kvm_get_sysreg_resx(kvm, sr).res0;
2439
2431
}
2440
2432
2441
2433
static bool check_fgt_bit(struct kvm_vcpu *vcpu, enum vcpu_sysreg sr,
+4
-9
arch/arm64/kvm/nested.c
+4
-9
arch/arm64/kvm/nested.c
···
1669
1669
u64 kvm_vcpu_apply_reg_masks(const struct kvm_vcpu *vcpu,
1670
1670
enum vcpu_sysreg sr, u64 v)
1671
1671
{
1672
-
struct kvm_sysreg_masks *masks;
1672
+
struct resx resx;
1673
1673
1674
-
masks = vcpu->kvm->arch.sysreg_masks;
1675
-
1676
-
if (masks) {
1677
-
sr -= __SANITISED_REG_START__;
1678
-
1679
-
v &= ~masks->mask[sr].res0;
1680
-
v |= masks->mask[sr].res1;
1681
-
}
1674
+
resx = kvm_get_sysreg_resx(vcpu->kvm, sr);
1675
+
v &= ~resx.res0;
1676
+
v |= resx.res1;
1682
1677
1683
1678
return v;
1684
1679
}