github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-30 01:53:29 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

KVM: arm64: Extend unified RESx handling to runtime sanitisation

Browse Source 
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>
This commit is contained in:
Marc Zyngier 2026-02-02 18:43:14 +00:00
parent 0879478913
commit f9d5895642
3 changed files with 20 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
arch/arm64/include/asm/kvm_host.h
View File

@ -635,6 +635,21 @@ struct kvm_sysreg_masks {
struct resx mask[NR_SYS_REGS - __SANITISED_REG_START__];
};
static inline struct resx __kvm_get_sysreg_resx(struct kvm_arch *arch,
enum vcpu_sysreg sr)
{
struct kvm_sysreg_masks *masks;
masks = arch->sysreg_masks;
if (likely(masks &&
sr >= __SANITISED_REG_START__ && sr < NR_SYS_REGS))
return masks->mask[sr - __SANITISED_REG_START__];
return (struct resx){};
}
#define kvm_get_sysreg_resx(k, sr) __kvm_get_sysreg_resx(&(k)->arch, (sr))
static inline void __kvm_set_sysreg_resx(struct kvm_arch *arch,
enum vcpu_sysreg sr, struct resx resx)
{

10
arch/arm64/kvm/emulate-nested.c
View File

@ -2427,15 +2427,7 @@ static enum trap_behaviour compute_trap_behaviour(struct kvm_vcpu *vcpu,
static u64 kvm_get_sysreg_res0(struct kvm *kvm, enum vcpu_sysreg sr)
{
struct kvm_sysreg_masks *masks;
/* Only handle the VNCR-backed regs for now */
if (sr < __VNCR_START__)
return 0;
masks = kvm->arch.sysreg_masks;
return masks->mask[sr - __SANITISED_REG_START__].res0;
return kvm_get_sysreg_resx(kvm, sr).res0;
}
static bool check_fgt_bit(struct kvm_vcpu *vcpu, enum vcpu_sysreg sr,

13
arch/arm64/kvm/nested.c
View File

@ -1669,16 +1669,11 @@ u64 limit_nv_id_reg(struct kvm *kvm, u32 reg, u64 val)
u64 kvm_vcpu_apply_reg_masks(const struct kvm_vcpu *vcpu,
enum vcpu_sysreg sr, u64 v)
{
struct kvm_sysreg_masks *masks;
struct resx resx;
masks = vcpu->kvm->arch.sysreg_masks;
if (masks) {
sr -= __SANITISED_REG_START__;
v &= ~masks->mask[sr].res0;
v |= masks->mask[sr].res1;
}
resx = kvm_get_sysreg_resx(vcpu->kvm, sr);
v &= ~resx.res0;
v |= resx.res1;
return v;
}