Patch "[Variant 2/Spectre-v2] arm/arm64: smccc: Implement SMCCC v1.1 inline primitive" has been added to the 4.15-stable tree

Patch "[Variant 2/Spectre-v2] arm/arm64: smccc: Implement SMCCC v1.1 inline primitive" has been added to the 4.15-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    [Variant 2/Spectre-v2] arm/arm64: smccc: Implement SMCCC v1.1 inline primitive

to the 4.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-arm64-smccc-implement-smccc-v1.1-inline-primitive.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Tue Feb 13 17:25:10 CET 2018
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Tue, 6 Feb 2018 17:56:19 +0000
Subject: [Variant 2/Spectre-v2] arm/arm64: smccc: Implement SMCCC v1.1 inline primitive

From: Marc Zyngier <marc.zyngier@arm.com>


Commit f2d3b2e8759a upstream.

One of the major improvement of SMCCC v1.1 is that it only clobbers
the first 4 registers, both on 32 and 64bit. This means that it
becomes very easy to provide an inline version of the SMC call
primitive, and avoid performing a function call to stash the
registers that would otherwise be clobbered by SMCCC v1.0.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/arm-smccc.h |  141 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 141 insertions(+)

--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -150,5 +150,146 @@ asmlinkage void __arm_smccc_hvc(unsigned
 
 #define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__)
 
+/* SMCCC v1.1 implementation madness follows */
+#ifdef CONFIG_ARM64
+
+#define SMCCC_SMC_INST	"smc	#0"
+#define SMCCC_HVC_INST	"hvc	#0"
+
+#elif defined(CONFIG_ARM)
+#include <asm/opcodes-sec.h>
+#include <asm/opcodes-virt.h>
+
+#define SMCCC_SMC_INST	__SMC(0)
+#define SMCCC_HVC_INST	__HVC(0)
+
+#endif
+
+#define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
+
+#define __count_args(...)						\
+	___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
+
+#define __constraint_write_0						\
+	"+r" (r0), "=&r" (r1), "=&r" (r2), "=&r" (r3)
+#define __constraint_write_1						\
+	"+r" (r0), "+r" (r1), "=&r" (r2), "=&r" (r3)
+#define __constraint_write_2						\
+	"+r" (r0), "+r" (r1), "+r" (r2), "=&r" (r3)
+#define __constraint_write_3						\
+	"+r" (r0), "+r" (r1), "+r" (r2), "+r" (r3)
+#define __constraint_write_4	__constraint_write_3
+#define __constraint_write_5	__constraint_write_4
+#define __constraint_write_6	__constraint_write_5
+#define __constraint_write_7	__constraint_write_6
+
+#define __constraint_read_0
+#define __constraint_read_1
+#define __constraint_read_2
+#define __constraint_read_3
+#define __constraint_read_4	"r" (r4)
+#define __constraint_read_5	__constraint_read_4, "r" (r5)
+#define __constraint_read_6	__constraint_read_5, "r" (r6)
+#define __constraint_read_7	__constraint_read_6, "r" (r7)
+
+#define __declare_arg_0(a0, res)					\
+	struct arm_smccc_res   *___res = res;				\
+	register u32           r0 asm("r0") = a0;			\
+	register unsigned long r1 asm("r1");				\
+	register unsigned long r2 asm("r2");				\
+	register unsigned long r3 asm("r3")
+
+#define __declare_arg_1(a0, a1, res)					\
+	struct arm_smccc_res   *___res = res;				\
+	register u32           r0 asm("r0") = a0;			\
+	register typeof(a1)    r1 asm("r1") = a1;			\
+	register unsigned long r2 asm("r2");				\
+	register unsigned long r3 asm("r3")
+
+#define __declare_arg_2(a0, a1, a2, res)				\
+	struct arm_smccc_res   *___res = res;				\
+	register u32           r0 asm("r0") = a0;			\
+	register typeof(a1)    r1 asm("r1") = a1;			\
+	register typeof(a2)    r2 asm("r2") = a2;			\
+	register unsigned long r3 asm("r3")
+
+#define __declare_arg_3(a0, a1, a2, a3, res)				\
+	struct arm_smccc_res   *___res = res;				\
+	register u32           r0 asm("r0") = a0;			\
+	register typeof(a1)    r1 asm("r1") = a1;			\
+	register typeof(a2)    r2 asm("r2") = a2;			\
+	register typeof(a3)    r3 asm("r3") = a3
+
+#define __declare_arg_4(a0, a1, a2, a3, a4, res)			\
+	__declare_arg_3(a0, a1, a2, a3, res);				\
+	register typeof(a4) r4 asm("r4") = a4
+
+#define __declare_arg_5(a0, a1, a2, a3, a4, a5, res)			\
+	__declare_arg_4(a0, a1, a2, a3, a4, res);			\
+	register typeof(a5) r5 asm("r5") = a5
+
+#define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res)		\
+	__declare_arg_5(a0, a1, a2, a3, a4, a5, res);			\
+	register typeof(a6) r6 asm("r6") = a6
+
+#define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
+	__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res);		\
+	register typeof(a7) r7 asm("r7") = a7
+
+#define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
+#define __declare_args(count, ...)  ___declare_args(count, __VA_ARGS__)
+
+#define ___constraints(count)						\
+	: __constraint_write_ ## count					\
+	: __constraint_read_ ## count					\
+	: "memory"
+#define __constraints(count)	___constraints(count)
+
+/*
+ * We have an output list that is not necessarily used, and GCC feels
+ * entitled to optimise the whole sequence away. "volatile" is what
+ * makes it stick.
+ */
+#define __arm_smccc_1_1(inst, ...)					\
+	do {								\
+		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
+		asm volatile(inst "\n"					\
+			     __constraints(__count_args(__VA_ARGS__)));	\
+		if (___res)						\
+			*___res = (typeof(*___res)){r0, r1, r2, r3};	\
+	} while (0)
+
+/*
+ * arm_smccc_1_1_smc() - make an SMCCC v1.1 compliant SMC call
+ *
+ * This is a variadic macro taking one to eight source arguments, and
+ * an optional return structure.
+ *
+ * @a0-a7: arguments passed in registers 0 to 7
+ * @res: result values from registers 0 to 3
+ *
+ * This macro is used to make SMC calls following SMC Calling Convention v1.1.
+ * The content of the supplied param are copied to registers 0 to 7 prior
+ * to the SMC instruction. The return values are updated with the content
+ * from register 0 to 3 on return from the SMC instruction if not NULL.
+ */
+#define arm_smccc_1_1_smc(...)	__arm_smccc_1_1(SMCCC_SMC_INST, __VA_ARGS__)
+
+/*
+ * arm_smccc_1_1_hvc() - make an SMCCC v1.1 compliant HVC call
+ *
+ * This is a variadic macro taking one to eight source arguments, and
+ * an optional return structure.
+ *
+ * @a0-a7: arguments passed in registers 0 to 7
+ * @res: result values from registers 0 to 3
+ *
+ * This macro is used to make HVC calls following SMC Calling Convention v1.1.
+ * The content of the supplied param are copied to registers 0 to 7 prior
+ * to the HVC instruction. The return values are updated with the content
+ * from register 0 to 3 on return from the HVC instruction if not NULL.
+ */
+#define arm_smccc_1_1_hvc(...)	__arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__)
+
 #endif /*__ASSEMBLY__*/
 #endif /*__LINUX_ARM_SMCCC_H*/


Patches currently in stable-queue which might be from marc.zyngier@arm.com are

queue-4.15/arm-arm64-smccc-make-function-identifiers-an-unsigned-quantity.patch
queue-4.15/arm64-move-bp-hardening-to-check_and_switch_context.patch
queue-4.15/arm-arm64-kvm-advertise-smccc-v1.1.patch
queue-4.15/arm64-move-post_ttbr_update_workaround-to-c-code.patch
queue-4.15/firmware-psci-expose-psci-conduit.patch
queue-4.15/arm64-force-kpti-to-be-disabled-on-cavium-thunderx.patch
queue-4.15/arm64-entry-apply-bp-hardening-for-high-priority-synchronous-exceptions.patch
queue-4.15/arm64-kpti-fix-the-interaction-between-asid-switching-and-software-pan.patch
queue-4.15/firmware-psci-expose-smccc-version-through-psci_ops.patch
queue-4.15/arm64-implement-branch-predictor-hardening-for-affected-cortex-a-cpus.patch
queue-4.15/arm-arm64-kvm-add-psci_version-helper.patch
queue-4.15/arm64-kill-psci_get_version-as-a-variant-2-workaround.patch
queue-4.15/arm64-entry-apply-bp-hardening-for-suspicious-interrupts-from-el0.patch
queue-4.15/arm64-capabilities-handle-duplicate-entries-for-a-capability.patch
queue-4.15/arm64-add-arm_smccc_arch_workaround_1-bp-hardening-support.patch
queue-4.15/arm-arm64-kvm-turn-kvm_psci_version-into-a-static-inline.patch
queue-4.15/arm-arm64-kvm-implement-psci-1.0-support.patch
queue-4.15/arm64-kvm-add-smccc_arch_workaround_1-fast-handling.patch
queue-4.15/arm64-kvm-report-smccc_arch_workaround_1-bp-hardening-support.patch
queue-4.15/arm-arm64-smccc-implement-smccc-v1.1-inline-primitive.patch
queue-4.15/arm64-idmap-use-awx-flags-for-.idmap.text-.pushsection-directives.patch
queue-4.15/arm64-kvm-make-psci_version-a-fast-path.patch
queue-4.15/arm64-cpufeature-__this_cpu_has_cap-shouldn-t-stop-early.patch
queue-4.15/arm64-kpti-add-enable-callback-to-remap-swapper-using-ng-mappings.patch
queue-4.15/arm-arm64-kvm-consolidate-the-psci-include-files.patch
queue-4.15/arm64-add-skeleton-to-harden-the-branch-predictor-against-aliasing-attacks.patch
queue-4.15/arm-arm64-kvm-add-smccc-accessors-to-psci-code.patch
queue-4.15/arm64-kvm-use-per-cpu-vector-when-bp-hardening-is-enabled.patch
queue-4.15/arm64-kvm-increment-pc-after-handling-an-smc-trap.patch