Patch "x86/retpoline/hyperv: Convert assembler indirect jumps" has been added to the 4.14-stable tree

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

x86/retpoline/hyperv: Convert assembler indirect jumps

to the 4.14-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:
x86-retpoline-hyperv-convert-assembler-indirect-jumps.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: David Woodhouse <[email protected]>
Date: Thu, 11 Jan 2018 21:46:30 +0000
Subject: x86/retpoline/hyperv: Convert assembler indirect jumps

From: David Woodhouse <[email protected]>

commit e70e5892b28c18f517f29ab6e83bd57705104b31 upstream.

Convert all indirect jumps in hyperv inline asm code to use non-speculative sequences when CONFIG_RETPOLINE is enabled.

---
 arch/x86/include/asm/mshyperv.h |   18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

@@ -7,6 +7,7 @@
 #include <linux/nmi.h>
 #include <asm/io.h>
 #include <asm/hyperv.h>
+#include <asm/nospec-branch.h>
 
 /*
  * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent

@@ -186,10 +187,11 @@ static inline u64 hv_do_hypercall(u64 co
 		return U64_MAX;
 
 	__asm__ __volatile__("mov %4, %%r8\n"
-			     "call *%5"
+			     CALL_NOSPEC
 			     : "=a" (hv_status), ASM_CALL_CONSTRAINT,
 			       "+c" (control), "+d" (input_address)
-			     :  "r" (output_address), "m" (hv_hypercall_pg)
+			     :  "r" (output_address),
+				THUNK_TARGET(hv_hypercall_pg)
 			     : "cc", "memory", "r8", "r9", "r10", "r11");
 #else
 	u32 input_address_hi = upper_32_bits(input_address);

@@ -200,13 +202,13 @@ static inline u64 hv_do_hypercall(u64 co
 	if (!hv_hypercall_pg)
 		return U64_MAX;
 
-	__asm__ __volatile__("call *%7"
+	__asm__ __volatile__(CALL_NOSPEC
 			     : "=A" (hv_status),
 			       "+c" (input_address_lo), ASM_CALL_CONSTRAINT
 			     : "A" (control),
 			       "b" (input_address_hi),
 			       "D"(output_address_hi), "S"(output_address_lo),
-			       "m" (hv_hypercall_pg)
+			       THUNK_TARGET(hv_hypercall_pg)
 			     : "cc", "memory");
 #endif /* !x86_64 */
 	return hv_status;

@@ -227,10 +229,10 @@ static inline u64 hv_do_fast_hypercall8(
 
 #ifdef CONFIG_X86_64
 	{
-		__asm__ __volatile__("call *%4"
+		__asm__ __volatile__(CALL_NOSPEC
 				     : "=a" (hv_status), ASM_CALL_CONSTRAINT,
 				       "+c" (control), "+d" (input1)
-				     : "m" (hv_hypercall_pg)
+				     : THUNK_TARGET(hv_hypercall_pg)
 				     : "cc", "r8", "r9", "r10", "r11");
 	}
 #else

@@ -238,13 +240,13 @@ static inline u64 hv_do_fast_hypercall8(
 		u32 input1_hi = upper_32_bits(input1);
 		u32 input1_lo = lower_32_bits(input1);
 
-		__asm__ __volatile__ ("call *%5"
+		__asm__ __volatile__ (CALL_NOSPEC
 				      : "=A"(hv_status),
 					"+c"(input1_lo),
 					ASM_CALL_CONSTRAINT
 				      :	"A" (control),
 					"b" (input1_hi),
-					"m" (hv_hypercall_pg)
+					THUNK_TARGET(hv_hypercall_pg)
 				      : "cc", "edi", "esi");
 	}
 #endif

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/x86-spectre-add-boot-time-option-to-select-spectre-v2-mitigation.patch queue-4.14/x86-retpoline-irq32-convert-assembler-indirect-jumps.patch queue-4.14/objtool-detect-jumps-to-retpoline-thunks.patch queue-4.14/x86-cpufeatures-add-x86_bug_spectre_v.patch queue-4.14/x86-retpoline-hyperv-convert-assembler-indirect-jumps.patch queue-4.14/x86-mm-pti-remove-dead-logic-in-pti_user_pagetable_walk.patch queue-4.14/x86-retpoline-entry-convert-entry-assembler-indirect-jumps.patch queue-4.14/sysfs-cpu-fix-typos-in-vulnerability-documentation.patch queue-4.14/x86-pti-fix-pcid-and-sanitize-defines.patch queue-4.14/x86-cpu-amd-make-lfence-a-serializing-instruction.patch queue-4.14/x86-retpoline-ftrace-convert-ftrace-assembler-indirect-jumps.patch queue-4.14/objtool-allow-alternatives-to-be-ignored.patch queue-4.14/x86-cpu-implement-cpu-vulnerabilites-sysfs-functions.patch queue-4.14/x86-retpoline-crypto-convert-crypto-assembler-indirect-jumps.patch queue-4.14/x86-tboot-unbreak-tboot-with-pti-enabled.patch queue-4.14/x86-retpoline-xen-convert-xen-hypercall-indirect-jumps.patch queue-4.14/x86-retpoline-checksum32-convert-assembler-indirect-jumps.patch queue-4.14/x86-pti-make-unpoison-of-pgd-for-trusted-boot-work-for-real.patch queue-4.14/sysfs-cpu-add-vulnerability-folder.patch queue-4.14/x86-retpoline-fill-return-stack-buffer-on-vmexit.patch queue-4.14/x86-retpoline-remove-compile-time-warning.patch queue-4.14/x86-cpu-amd-use-lfence_rdtsc-in-preference-to-mfence_rdtsc.patch queue-4.14/x86-retpoline-add-initial-retpoline-support.patch