diff options
Diffstat (limited to 'arch/arm64/kernel/hyp-stub.S')
-rw-r--r-- | arch/arm64/kernel/hyp-stub.S | 40 |
1 files changed, 27 insertions, 13 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 678cd2c618ee..5eccbd62fec8 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -75,9 +75,6 @@ SYM_CODE_END(el1_sync) // nVHE? No way! Give me the real thing! SYM_CODE_START_LOCAL(mutate_to_vhe) - // Be prepared to fail - mov_q x0, HVC_STUB_ERR - // Sanity check: MMU *must* be off mrs x1, sctlr_el2 tbnz x1, #0, 1f @@ -96,8 +93,11 @@ SYM_CODE_START_LOCAL(mutate_to_vhe) cmp x1, xzr and x2, x2, x1 csinv x2, x2, xzr, ne - cbz x2, 1f + cbnz x2, 2f +1: mov_q x0, HVC_STUB_ERR + eret +2: // Engage the VHE magic! mov_q x0, HCR_HOST_VHE_FLAGS msr hcr_el2, x0 @@ -131,9 +131,28 @@ SYM_CODE_START_LOCAL(mutate_to_vhe) msr mair_el1, x0 isb + // Hack the exception return to stay at EL2 + mrs x0, spsr_el1 + and x0, x0, #~PSR_MODE_MASK + mov x1, #PSR_MODE_EL2h + orr x0, x0, x1 + msr spsr_el1, x0 + + b enter_vhe +SYM_CODE_END(mutate_to_vhe) + + // At the point where we reach enter_vhe(), we run with + // the MMU off (which is enforced by mutate_to_vhe()). + // We thus need to be in the idmap, or everything will + // explode when enabling the MMU. + + .pushsection .idmap.text, "ax" + +SYM_CODE_START_LOCAL(enter_vhe) // Invalidate TLBs before enabling the MMU tlbi vmalle1 dsb nsh + isb // Enable the EL2 S1 MMU, as set up from EL1 mrs_s x0, SYS_SCTLR_EL12 @@ -143,17 +162,12 @@ SYM_CODE_START_LOCAL(mutate_to_vhe) mov_q x0, INIT_SCTLR_EL1_MMU_OFF msr_s SYS_SCTLR_EL12, x0 - // Hack the exception return to stay at EL2 - mrs x0, spsr_el1 - and x0, x0, #~PSR_MODE_MASK - mov x1, #PSR_MODE_EL2h - orr x0, x0, x1 - msr spsr_el1, x0 - mov x0, xzr -1: eret -SYM_CODE_END(mutate_to_vhe) + eret +SYM_CODE_END(enter_vhe) + + .popsection .macro invalid_vector label SYM_CODE_START_LOCAL(\label) |