mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

KVM: arm64: Move hyp-init params to a per-CPU struct 

Once we start initializing KVM on newly booted cores before the rest of
the kernel, parameters to __do_hyp_init will need to be provided by EL2
rather than EL1. At that point it will not be possible to pass its three
arguments directly because PSCI_CPU_ON only supports one context
argument.

Refactor __do_hyp_init to accept its parameters in a struct. This
prepares the code for KVM booting cores as well as removes any limits on
the number of __do_hyp_init arguments.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-11-dbrazdil@google.com
This commit is contained in:
David Brazdil 2020-12-02 18:41:06 +00:00 committed by Marc Zyngier
parent 5be1d6226d
commit 63fec24351
6 changed files with 32 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/arm64/include/asm/kvm_asm.h
View File

@ -150,6 +150,12 @@ extern void *__vhe_undefined_symbol;
#endif
struct kvm_nvhe_init_params {
unsigned long tpidr_el2;
unsigned long stack_hyp_va;
phys_addr_t pgd_pa;
};
/* Translate a kernel address @ptr into its equivalent linear mapping */
#define kvm_ksym_ref(ptr) \
({ \

2
arch/arm64/include/asm/kvm_hyp.h
View File

@ -14,6 +14,7 @@
DECLARE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
DECLARE_PER_CPU(unsigned long, kvm_hyp_vector);
DECLARE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
#define read_sysreg_elx(r,nvh,vh) \
({ \
@ -98,4 +99,3 @@ void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par);
#endif
#endif /* __ARM64_KVM_HYP_H__ */

3
arch/arm64/kernel/asm-offsets.c
View File

@ -109,6 +109,9 @@ int main(void)
DEFINE(CPU_APGAKEYLO_EL1, offsetof(struct kvm_cpu_context, sys_regs[APGAKEYLO_EL1]));
DEFINE(HOST_CONTEXT_VCPU, offsetof(struct kvm_cpu_context, __hyp_running_vcpu));
DEFINE(HOST_DATA_CONTEXT, offsetof(struct kvm_host_data, host_ctxt));
DEFINE(NVHE_INIT_TPIDR_EL2, offsetof(struct kvm_nvhe_init_params, tpidr_el2));
DEFINE(NVHE_INIT_STACK_HYP_VA, offsetof(struct kvm_nvhe_init_params, stack_hyp_va));
DEFINE(NVHE_INIT_PGD_PA, offsetof(struct kvm_nvhe_init_params, pgd_pa));
#endif
#ifdef CONFIG_CPU_PM
DEFINE(CPU_CTX_SP, offsetof(struct cpu_suspend_ctx, sp));

23
arch/arm64/kvm/arm.c
View File

@ -52,6 +52,7 @@ DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];
DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
/* The VMID used in the VTTBR */
static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
@ -1333,9 +1334,7 @@ static int kvm_map_vectors(void)
static void cpu_init_hyp_mode(void)
{
phys_addr_t pgd_ptr;
unsigned long hyp_stack_ptr;
unsigned long tpidr_el2;
struct kvm_nvhe_init_params *params = this_cpu_ptr_nvhe_sym(kvm_init_params);
struct arm_smccc_res res;
/* Switch from the HYP stub to our own HYP init vector */
@ -1346,12 +1345,17 @@ static void cpu_init_hyp_mode(void)
* kernel's mapping to the linear mapping, and store it in tpidr_el2
* so that we can use adr_l to access per-cpu variables in EL2.
*/
tpidr_el2 = (unsigned long)this_cpu_ptr_nvhe_sym(__per_cpu_start) -
(unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
params->tpidr_el2 = (unsigned long)this_cpu_ptr_nvhe_sym(__per_cpu_start) -
(unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
pgd_ptr = kvm_mmu_get_httbr();
hyp_stack_ptr = __this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE;
hyp_stack_ptr = kern_hyp_va(hyp_stack_ptr);
params->stack_hyp_va = kern_hyp_va(__this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE);
params->pgd_pa = kvm_mmu_get_httbr();
/*
* Flush the init params from the data cache because the struct will
* be read while the MMU is off.
*/
kvm_flush_dcache_to_poc(params, sizeof(*params));
/*
* Call initialization code, and switch to the full blown HYP code.
@ -1360,8 +1364,7 @@ static void cpu_init_hyp_mode(void)
* cpus_have_const_cap() wrapper.
*/
BUG_ON(!system_capabilities_finalized());
arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init),
pgd_ptr, tpidr_el2, hyp_stack_ptr, &res);
arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
/*

16
arch/arm64/kvm/hyp/nvhe/hyp-init.S
View File

@ -47,9 +47,7 @@ __invalid:
/*
* x0: SMCCC function ID
* x1: HYP pgd
* x2: per-CPU offset
* x3: HYP stack
* x1: struct kvm_nvhe_init_params PA
*/
__do_hyp_init:
/* Check for a stub HVC call */
@ -70,10 +68,13 @@ __do_hyp_init:
mov x0, #SMCCC_RET_NOT_SUPPORTED
eret
1:
/* Set tpidr_el2 for use by HYP to free a register */
msr tpidr_el2, x2
1: ldr x0, [x1, #NVHE_INIT_TPIDR_EL2]
msr tpidr_el2, x0
ldr x0, [x1, #NVHE_INIT_STACK_HYP_VA]
mov sp, x0
ldr x1, [x1, #NVHE_INIT_PGD_PA]
phys_to_ttbr x0, x1
alternative_if ARM64_HAS_CNP
orr x0, x0, #TTBR_CNP_BIT
@ -133,9 +134,6 @@ alternative_else_nop_endif
msr sctlr_el2, x0
isb
/* Set the stack */
mov sp, x3
/* Set the host vector */
ldr x0, =__kvm_hyp_host_vector
kimg_hyp_va x0, x1

2
arch/arm64/kvm/hyp/nvhe/hyp-main.c
View File

@ -16,6 +16,8 @@
#define DECLARE_REG(type, name, ctxt, reg) \
type name = (type)cpu_reg(ctxt, (reg))
DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);