Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull more arm64 updates from Catalin Marinas:
 "As I mentioned in the last pull request, there's a second batch of
  security updates for arm64 with mitigations for Spectre/v1 and an
  improved one for Spectre/v2 (via a newly defined firmware interface
  API).

  Spectre v1 mitigation:

   - back-end version of array_index_mask_nospec()

   - masking of the syscall number to restrict speculation through the
     syscall table

   - masking of __user pointers prior to deference in uaccess routines

  Spectre v2 mitigation update:

   - using the new firmware SMC calling convention specification update

   - removing the current PSCI GET_VERSION firmware call mitigation as
     vendors are deploying new SMCCC-capable firmware

   - additional branch predictor hardening for synchronous exceptions
     and interrupts while in user mode

  Meltdown v3 mitigation update:

    - Cavium Thunder X is unaffected but a hardware erratum gets in the
      way. The kernel now starts with the page tables mapped as global
      and switches to non-global if kpti needs to be enabled.

  Other:

   - Theoretical trylock bug fixed"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (38 commits)
  arm64: Kill PSCI_GET_VERSION as a variant-2 workaround
  arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening support
  arm/arm64: smccc: Implement SMCCC v1.1 inline primitive
  arm/arm64: smccc: Make function identifiers an unsigned quantity
  firmware/psci: Expose SMCCC version through psci_ops
  firmware/psci: Expose PSCI conduit
  arm64: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handling
  arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support
  arm/arm64: KVM: Turn kvm_psci_version into a static inline
  arm/arm64: KVM: Advertise SMCCC v1.1
  arm/arm64: KVM: Implement PSCI 1.0 support
  arm/arm64: KVM: Add smccc accessors to PSCI code
  arm/arm64: KVM: Add PSCI_VERSION helper
  arm/arm64: KVM: Consolidate the PSCI include files
  arm64: KVM: Increment PC after handling an SMC trap
  arm: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls
  arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls
  arm64: entry: Apply BP hardening for suspicious interrupts from EL0
  arm64: entry: Apply BP hardening for high-priority synchronous exceptions
  arm64: futex: Mask __user pointers prior to dereference
  ...

1 files changed, 18 insertions, 2 deletions

diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index e4f37b9dd47c..f36464bd57c5 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -15,6 +15,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/arm-smccc.h>
 #include <linux/linkage.h>
 
 #include <asm/alternative.h>
@@ -64,10 +65,11 @@ alternative_endif
 	lsr	x0, x1, #ESR_ELx_EC_SHIFT
 
 	cmp	x0, #ESR_ELx_EC_HVC64
+	ccmp	x0, #ESR_ELx_EC_HVC32, #4, ne
 	b.ne	el1_trap
 
-	mrs	x1, vttbr_el2		// If vttbr is valid, the 64bit guest
-	cbnz	x1, el1_trap		// called HVC
+	mrs	x1, vttbr_el2		// If vttbr is valid, the guest
+	cbnz	x1, el1_hvc_guest	// called HVC
 
 	/* Here, we're pretty sure the host called HVC. */
 	ldp	x0, x1, [sp], #16
@@ -100,6 +102,20 @@ alternative_endif
 
 	eret
 
+el1_hvc_guest:
+	/*
+	 * Fastest possible path for ARM_SMCCC_ARCH_WORKAROUND_1.
+	 * The workaround has already been applied on the host,
+	 * so let's quickly get back to the guest. We don't bother
+	 * restoring x1, as it can be clobbered anyway.
+	 */
+	ldr	x1, [sp]				// Guest's x0
+	eor	w1, w1, #ARM_SMCCC_ARCH_WORKAROUND_1
+	cbnz	w1, el1_trap
+	mov	x0, x1
+	add	sp, sp, #16
+	eret
+
 el1_trap:
 	/*
 	 * x0: ESR_EC