diff options
Diffstat (limited to 'arch/arm64/kvm/hyp-init.S')
| -rw-r--r-- | arch/arm64/kvm/hyp-init.S | 48 |
1 files changed, 46 insertions, 2 deletions
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index 178ba2248a98..3270d392970d 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -21,6 +21,7 @@ #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> #include <asm/pgtable-hwdef.h> +#include <asm/sysreg.h> .text .pushsection .hyp.idmap.text, "ax" @@ -105,8 +106,8 @@ __do_hyp_init: dsb sy mrs x4, sctlr_el2 - and x4, x4, #SCTLR_EL2_EE // preserve endianness of EL2 - ldr x5, =SCTLR_EL2_FLAGS + and x4, x4, #SCTLR_ELx_EE // preserve endianness of EL2 + ldr x5, =SCTLR_ELx_FLAGS orr x4, x4, x5 msr sctlr_el2, x4 isb @@ -140,6 +141,49 @@ merged: eret ENDPROC(__kvm_hyp_init) + /* + * Reset kvm back to the hyp stub. This is the trampoline dance in + * reverse. If kvm used an extended idmap, __extended_idmap_trampoline + * calls this code directly in the idmap. In this case switching to the + * boot tables is a no-op. + * + * x0: HYP boot pgd + * x1: HYP phys_idmap_start + */ +ENTRY(__kvm_hyp_reset) + /* We're in trampoline code in VA, switch back to boot page tables */ + msr ttbr0_el2, x0 + isb + + /* Ensure the PA branch doesn't find a stale tlb entry or stale code. */ + ic iallu + tlbi alle2 + dsb sy + isb + + /* Branch into PA space */ + adr x0, 1f + bfi x1, x0, #0, #PAGE_SHIFT + br x1 + + /* We're now in idmap, disable MMU */ +1: mrs x0, sctlr_el2 + ldr x1, =SCTLR_ELx_FLAGS + bic x0, x0, x1 // Clear SCTL_M and etc + msr sctlr_el2, x0 + isb + + /* Invalidate the old TLBs */ + tlbi alle2 + dsb sy + + /* Install stub vectors */ + adr_l x0, __hyp_stub_vectors + msr vbar_el2, x0 + + eret +ENDPROC(__kvm_hyp_reset) + .ltorg .popsection |