| Message ID | 20201109175923.445945-4-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: Host EL2 entry improvements | expand |
Hey Marc, Just noticed in kvmarm/queue that the whitespacing in this patch is off. > +.macro kimg_pa reg, tmp > +alternative_cb kvm_get_kimage_voffset > + movz \tmp, #0 > + movk \tmp, #0, lsl #16 > + movk \tmp, #0, lsl #32 > + movk \tmp, #0, lsl #48 > +alternative_cb_end > + > + /* reg = __pa(reg) */ > + sub \reg, \reg, \tmp > +.endm This uses spaces instead of tabs. > + > #else This added empty line actually has a tab in it. -David
On 2020-11-19 11:14, David Brazdil wrote: > Hey Marc, > > Just noticed in kvmarm/queue that the whitespacing in this patch is > off. > >> +.macro kimg_pa reg, tmp >> +alternative_cb kvm_get_kimage_voffset >> + movz \tmp, #0 >> + movk \tmp, #0, lsl #16 >> + movk \tmp, #0, lsl #32 >> + movk \tmp, #0, lsl #48 >> +alternative_cb_end >> + >> + /* reg = __pa(reg) */ >> + sub \reg, \reg, \tmp >> +.endm > This uses spaces instead of tabs. > >> + >> #else > This added empty line actually has a tab in it. Well spotted. Now fixed. Thanks, M.
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 608c3a83e740..400d2d73ce12 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -72,6 +72,28 @@ alternative_cb kvm_update_va_mask alternative_cb_end .endm +/* + * Convert a kernel image address to a PA + * reg: kernel address to be converted in place + * tmp: temporary register + * + * The actual code generation takes place in kvm_get_kimage_voffset, and + * the instructions below are only there to reserve the space and + * perform the register allocation (kvm_get_kimage_voffset uses the + * specific registers encoded in the instructions). + */ +.macro kimg_pa reg, tmp +alternative_cb kvm_get_kimage_voffset + movz \tmp, #0 + movk \tmp, #0, lsl #16 + movk \tmp, #0, lsl #32 + movk \tmp, #0, lsl #48 +alternative_cb_end + + /* reg = __pa(reg) */ + sub \reg, \reg, \tmp +.endm + #else #include <linux/pgtable.h> diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index e8c194f8de88..4b32588918d9 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -65,13 +65,11 @@ __efistub__ctype = _ctype; KVM_NVHE_ALIAS(kvm_patch_vector_branch); KVM_NVHE_ALIAS(kvm_update_va_mask); KVM_NVHE_ALIAS(kvm_update_kimg_phys_offset); +KVM_NVHE_ALIAS(kvm_get_kimage_voffset); /* Global kernel state accessed by nVHE hyp code. */ KVM_NVHE_ALIAS(kvm_vgic_global_state); -/* Kernel constant needed to compute idmap addresses. */ -KVM_NVHE_ALIAS(kimage_voffset); - /* Kernel symbols used to call panic() from nVHE hyp code (via ERET). */ KVM_NVHE_ALIAS(__hyp_panic_string); KVM_NVHE_ALIAS(panic); diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index ed27f06a31ba..4e207c1c5126 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -115,10 +115,7 @@ SYM_FUNC_END(__hyp_do_panic) * Preserve x0-x4, which may contain stub parameters. */ ldr x5, =__kvm_handle_stub_hvc - ldr_l x6, kimage_voffset - - /* x5 = __pa(x5) */ - sub x5, x5, x6 + kimg_pa x5, x6 br x5 .L__vect_end\@: .if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index 1d00d2cb93fd..d61117805de0 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -251,3 +251,9 @@ void kvm_update_kimg_phys_offset(struct alt_instr *alt, { 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); +}
Directly using the kimage_voffset variable is fine for now, but will become more problematic as we start distrusting EL1. Instead, patch the kimage_voffset into the HYP text, ensuring we don't have to load an untrusted value later on. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/include/asm/kvm_mmu.h | 22 ++++++++++++++++++++++ arch/arm64/kernel/image-vars.h | 4 +--- arch/arm64/kvm/hyp/nvhe/host.S | 5 +---- arch/arm64/kvm/va_layout.c | 6 ++++++ 4 files changed, 30 insertions(+), 7 deletions(-)