diff options
| author | Marc Zyngier <maz@kernel.org> | 2024-10-23 16:53:14 +0200 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2024-10-31 03:42:29 +0100 |
| commit | 164b5e20cdf6038f1b38867d2f6252ec6f10c356 (patch) | |
| tree | 6894bd0f2d469d83a822f07475999655825d4663 /include/kvm | |
| parent | KVM: arm64: nv: Add missing EL2->EL1 mappings in get_el2_to_el1_mapping() (diff) | |
| download | linux-164b5e20cdf6038f1b38867d2f6252ec6f10c356.tar.xz linux-164b5e20cdf6038f1b38867d2f6252ec6f10c356.zip | |
KVM: arm64: nv: Handle CNTHCTL_EL2 specially
Accessing CNTHCTL_EL2 is fraught with danger if running with
HCR_EL2.E2H=1: half of the bits are held in CNTKCTL_EL1, and
thus can be changed behind our back, while the rest lives
in the CNTHCTL_EL2 shadow copy that is memory-based.
Yes, this is a lot of fun!
Make sure that we merge the two on read access, while we can
write to CNTKCTL_EL1 in a more straightforward manner.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241023145345.1613824-7-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Diffstat (limited to '')
| -rw-r--r-- | include/kvm/arm_arch_timer.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index c819c5d16613..fd650a8789b9 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -147,6 +147,9 @@ u64 timer_get_cval(struct arch_timer_context *ctxt); void kvm_timer_cpu_up(void); void kvm_timer_cpu_down(void); +/* CNTKCTL_EL1 valid bits as of DDI0487J.a */ +#define CNTKCTL_VALID_BITS (BIT(17) | GENMASK_ULL(9, 0)) + static inline bool has_cntpoff(void) { return (has_vhe() && cpus_have_final_cap(ARM64_HAS_ECV_CNTPOFF)); |