kvm: arm64: Remove __hyp_this_cpu_read

this_cpu_ptr is meant for use in kernel proper because it selects between
TPIDR_EL1/2 based on nVHE/VHE. __hyp_this_cpu_ptr was used in hyp to always
select TPIDR_EL2. Unify all users behind this_cpu_ptr and friends by
selecting _EL2 register under __KVM_NVHE_HYPERVISOR__. VHE continues
selecting the register using alternatives.

Under CONFIG_DEBUG_PREEMPT, the kernel helpers perform a preemption check
which is omitted by the hyp helpers. Preserve the behavior for nVHE by
overriding the corresponding macros under __KVM_NVHE_HYPERVISOR__. Extend
the checks into VHE hyp code.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Andrew Scull <ascull@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200922204910.7265-5-dbrazdil@google.com
This commit is contained in:
David Brazdil 2020-09-22 21:49:04 +01:00 committed by Marc Zyngier
parent 3471ee06e3
commit 717cf94adb
7 changed files with 36 additions and 32 deletions

View File

@ -143,26 +143,6 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
addr; \
})
/*
* Home-grown __this_cpu_{ptr,read} variants that always work at HYP,
* provided that sym is really a *symbol* and not a pointer obtained from
* a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps
* sparse quiet.
*/
#define __hyp_this_cpu_ptr(sym) \
({ \
void *__ptr; \
__verify_pcpu_ptr(&sym); \
__ptr = hyp_symbol_addr(sym); \
__ptr += read_sysreg(tpidr_el2); \
(typeof(sym) __kernel __force *)__ptr; \
})
#define __hyp_this_cpu_read(sym) \
({ \
*__hyp_this_cpu_ptr(sym); \
})
#define __KVM_EXTABLE(from, to) \
" .pushsection __kvm_ex_table, \"a\"\n" \
" .align 3\n" \

View File

@ -19,7 +19,16 @@ static inline void set_my_cpu_offset(unsigned long off)
:: "r" (off) : "memory");
}
static inline unsigned long __my_cpu_offset(void)
static inline unsigned long __hyp_my_cpu_offset(void)
{
/*
* Non-VHE hyp code runs with preemption disabled. No need to hazard
* the register access against barrier() as in __kern_my_cpu_offset.
*/
return read_sysreg(tpidr_el2);
}
static inline unsigned long __kern_my_cpu_offset(void)
{
unsigned long off;
@ -35,7 +44,12 @@ static inline unsigned long __my_cpu_offset(void)
return off;
}
#define __my_cpu_offset __my_cpu_offset()
#ifdef __KVM_NVHE_HYPERVISOR__
#define __my_cpu_offset __hyp_my_cpu_offset()
#else
#define __my_cpu_offset __kern_my_cpu_offset()
#endif
#define PERCPU_RW_OPS(sz) \
static inline unsigned long __percpu_read_##sz(void *ptr) \
@ -227,4 +241,14 @@ PERCPU_RET_OP(add, add, ldadd)
#include <asm-generic/percpu.h>
/* Redefine macros for nVHE hyp under DEBUG_PREEMPT to avoid its dependencies. */
#if defined(__KVM_NVHE_HYPERVISOR__) && defined(CONFIG_DEBUG_PREEMPT)
#undef this_cpu_ptr
#define this_cpu_ptr raw_cpu_ptr
#undef __this_cpu_read
#define __this_cpu_read raw_cpu_read
#undef __this_cpu_write
#define __this_cpu_write raw_cpu_write
#endif
#endif /* __ASM_PERCPU_H */

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@ -135,7 +135,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu)
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
@ -154,7 +154,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu)
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);

View File

@ -386,7 +386,7 @@ static inline bool __hyp_handle_ptrauth(struct kvm_vcpu *vcpu)
!esr_is_ptrauth_trap(kvm_vcpu_get_esr(vcpu)))
return false;
ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
__ptrauth_save_key(ctxt, APIA);
__ptrauth_save_key(ctxt, APIB);
__ptrauth_save_key(ctxt, APDA);
@ -495,7 +495,7 @@ static inline void __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu)
* guest wants it disabled, so be it...
*/
if (__needs_ssbd_off(vcpu) &&
__hyp_this_cpu_read(arm64_ssbd_callback_required))
__this_cpu_read(arm64_ssbd_callback_required))
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL);
#endif
}
@ -507,7 +507,7 @@ static inline void __set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
* If the guest has disabled the workaround, bring it back on.
*/
if (__needs_ssbd_off(vcpu) &&
__hyp_this_cpu_read(arm64_ssbd_callback_required))
__this_cpu_read(arm64_ssbd_callback_required))
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL);
#endif
}
@ -521,7 +521,7 @@ static inline void __kvm_unexpected_el2_exception(void)
entry = hyp_symbol_addr(__start___kvm_ex_table);
end = hyp_symbol_addr(__stop___kvm_ex_table);
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
while (entry < end) {
addr = (unsigned long)&entry->insn + entry->insn;

View File

@ -175,7 +175,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
vcpu = kern_hyp_va(vcpu);
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
host_ctxt->__hyp_running_vcpu = vcpu;
guest_ctxt = &vcpu->arch.ctxt;

View File

@ -108,7 +108,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt;
u64 exit_code;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
host_ctxt->__hyp_running_vcpu = vcpu;
guest_ctxt = &vcpu->arch.ctxt;

View File

@ -66,7 +66,7 @@ void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
struct kvm_cpu_context *host_ctxt;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
__sysreg_save_user_state(host_ctxt);
/*
@ -100,7 +100,7 @@ void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
struct kvm_cpu_context *host_ctxt;
host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
deactivate_traps_vhe_put();
__sysreg_save_el1_state(guest_ctxt);