diff options
Diffstat (limited to 'arch/arm64/kvm/va_layout.c')
| -rw-r--r-- | arch/arm64/kvm/va_layout.c | 104 |
1 files changed, 85 insertions, 19 deletions
diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index e0404bcab019..d8cc51bd60bf 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -11,6 +11,7 @@ #include <asm/debug-monitors.h> #include <asm/insn.h> #include <asm/kvm_mmu.h> +#include <asm/memory.h> /* * The LSB of the HYP VA tag @@ -23,6 +24,30 @@ static u64 tag_val; static u64 va_mask; /* + * Compute HYP VA by using the same computation as kern_hyp_va(). + */ +static u64 __early_kern_hyp_va(u64 addr) +{ + addr &= va_mask; + addr |= tag_val << tag_lsb; + return addr; +} + +/* + * Store a hyp VA <-> PA offset into a hyp-owned variable. + */ +static void init_hyp_physvirt_offset(void) +{ + extern s64 kvm_nvhe_sym(hyp_physvirt_offset); + u64 kern_va, hyp_va; + + /* Compute the offset from the hyp VA and PA of a random symbol. */ + kern_va = (u64)kvm_ksym_ref(__hyp_text_start); + hyp_va = __early_kern_hyp_va(kern_va); + CHOOSE_NVHE_SYM(hyp_physvirt_offset) = (s64)__pa(kern_va) - (s64)hyp_va; +} + +/* * We want to generate a hyp VA with the following format (with V == * vabits_actual): * @@ -53,6 +78,8 @@ __init void kvm_compute_layout(void) tag_val |= get_random_long() & GENMASK_ULL(vabits_actual - 2, tag_lsb); } tag_val >>= tag_lsb; + + init_hyp_physvirt_offset(); } static u32 compute_instruction(int n, u32 rd, u32 rn) @@ -131,28 +158,21 @@ void __init kvm_update_va_mask(struct alt_instr *alt, } } -void *__kvm_bp_vect_base; -int __kvm_harden_el2_vector_slot; - void kvm_patch_vector_branch(struct alt_instr *alt, __le32 *origptr, __le32 *updptr, int nr_inst) { u64 addr; u32 insn; - BUG_ON(nr_inst != 5); + BUG_ON(nr_inst != 4); - if (has_vhe() || !cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) { - WARN_ON_ONCE(cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)); + if (!cpus_have_const_cap(ARM64_SPECTRE_V3A) || WARN_ON_ONCE(has_vhe())) return; - } /* * Compute HYP VA by using the same computation as kern_hyp_va() */ - addr = (uintptr_t)kvm_ksym_ref(__kvm_hyp_vector); - addr &= va_mask; - addr |= tag_val << tag_lsb; + addr = __early_kern_hyp_va((u64)kvm_ksym_ref(__kvm_hyp_vector)); /* Use PC[10:7] to branch to the same vector in KVM */ addr |= ((u64)origptr & GENMASK_ULL(10, 7)); @@ -163,15 +183,6 @@ void kvm_patch_vector_branch(struct alt_instr *alt, */ addr += KVM_VECTOR_PREAMBLE; - /* stp x0, x1, [sp, #-16]! */ - insn = aarch64_insn_gen_load_store_pair(AARCH64_INSN_REG_0, - AARCH64_INSN_REG_1, - AARCH64_INSN_REG_SP, - -16, - AARCH64_INSN_VARIANT_64BIT, - AARCH64_INSN_LDST_STORE_PAIR_PRE_INDEX); - *updptr++ = cpu_to_le32(insn); - /* movz x0, #(addr & 0xffff) */ insn = aarch64_insn_gen_movewide(AARCH64_INSN_REG_0, (u16)addr, @@ -201,3 +212,58 @@ void kvm_patch_vector_branch(struct alt_instr *alt, AARCH64_INSN_BRANCH_NOLINK); *updptr++ = cpu_to_le32(insn); } + +static void generate_mov_q(u64 val, __le32 *origptr, __le32 *updptr, int nr_inst) +{ + u32 insn, oinsn, rd; + + BUG_ON(nr_inst != 4); + + /* Compute target register */ + oinsn = le32_to_cpu(*origptr); + rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, oinsn); + + /* movz rd, #(val & 0xffff) */ + insn = aarch64_insn_gen_movewide(rd, + (u16)val, + 0, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_ZERO); + *updptr++ = cpu_to_le32(insn); + + /* movk rd, #((val >> 16) & 0xffff), lsl #16 */ + insn = aarch64_insn_gen_movewide(rd, + (u16)(val >> 16), + 16, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_KEEP); + *updptr++ = cpu_to_le32(insn); + + /* movk rd, #((val >> 32) & 0xffff), lsl #32 */ + insn = aarch64_insn_gen_movewide(rd, + (u16)(val >> 32), + 32, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_KEEP); + *updptr++ = cpu_to_le32(insn); + + /* movk rd, #((val >> 48) & 0xffff), lsl #48 */ + insn = aarch64_insn_gen_movewide(rd, + (u16)(val >> 48), + 48, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_KEEP); + *updptr++ = cpu_to_le32(insn); +} + +void kvm_update_kimg_phys_offset(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst) +{ + generate_mov_q(kimage_voffset + PHYS_OFFSET, origptr, updptr, nr_inst); +} + +void kvm_get_kimage_voffset(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst) +{ + generate_mov_q(kimage_voffset, origptr, updptr, nr_inst); +} |