diff options
Diffstat (limited to 'arch/arm64/kernel/hyp-stub.S')
| -rw-r--r-- | arch/arm64/kernel/hyp-stub.S | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 571286eb443c..43c94e7a2c1d 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -16,6 +16,25 @@ #include <asm/ptrace.h> #include <asm/virt.h> +// Warning, hardcoded register allocation +// This will clobber x1 and x2. +.macro check_override idreg, fld, pass, fail + mrs x1, \idreg\()_el1 + ubfx x1, x1, #\fld, #4 + cbz x1, \fail + + adr_l x1, \idreg\()_override + ldr x2, [x1, FTR_OVR_VAL_OFFSET] + ldr x1, [x1, FTR_OVR_MASK_OFFSET] + ubfx x2, x2, #\fld, #4 + ubfx x1, x1, #\fld, #4 + cmp x1, xzr + and x2, x2, x1 + csinv x2, x2, xzr, ne + cbnz x2, \pass + b \fail +.endm + .text .pushsection .hyp.text, "ax" @@ -80,20 +99,7 @@ SYM_CODE_START_LOCAL(__finalise_el2) tbnz x1, #0, 1f // Needs to be VHE capable, obviously - mrs x1, id_aa64mmfr1_el1 - ubfx x1, x1, #ID_AA64MMFR1_VHE_SHIFT, #4 - cbz x1, 1f - - // Check whether VHE is disabled from the command line - adr_l x1, id_aa64mmfr1_override - ldr x2, [x1, FTR_OVR_VAL_OFFSET] - ldr x1, [x1, FTR_OVR_MASK_OFFSET] - ubfx x2, x2, #ID_AA64MMFR1_VHE_SHIFT, #4 - ubfx x1, x1, #ID_AA64MMFR1_VHE_SHIFT, #4 - cmp x1, xzr - and x2, x2, x1 - csinv x2, x2, xzr, ne - cbnz x2, 2f + check_override id_aa64mmfr1 ID_AA64MMFR1_VHE_SHIFT 2f 1f 1: mov_q x0, HVC_STUB_ERR eret |