Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 core updates from Borislav Petkov:

 - Get rid of all the .fixup sections because this generates
   misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
   LIVEPATCH as the backtrace misses the function which is being fixed
   up.

 - Add Straight Line Speculation mitigation support which uses a new
   compiler switch -mharden-sls= which sticks an INT3 after a RET or an
   indirect branch in order to block speculation after them. Reportedly,
   CPUs do speculate behind such insns.

 - The usual set of cleanups and improvements

* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/entry_32: Fix segment exceptions
  objtool: Remove .fixup handling
  x86: Remove .fixup section
  x86/word-at-a-time: Remove .fixup usage
  x86/usercopy: Remove .fixup usage
  x86/usercopy_32: Simplify __copy_user_intel_nocache()
  x86/sgx: Remove .fixup usage
  x86/checksum_32: Remove .fixup usage
  x86/vmx: Remove .fixup usage
  x86/kvm: Remove .fixup usage
  x86/segment: Remove .fixup usage
  x86/fpu: Remove .fixup usage
  x86/xen: Remove .fixup usage
  x86/uaccess: Remove .fixup usage
  x86/futex: Remove .fixup usage
  x86/msr: Remove .fixup usage
  x86/extable: Extend extable functionality
  x86/entry_32: Remove .fixup usage
  x86/entry_64: Remove .fixup usage
  x86/copy_mc_64: Remove .fixup usage
  ...

1 files changed, 5 insertions, 31 deletions

diff --git a/arch/x86/kernel/cpu/sgx/encls.h b/arch/x86/kernel/cpu/sgx/encls.h
index 9b204843b78d..fa04a73daf9c 100644
--- a/arch/x86/kernel/cpu/sgx/encls.h
+++ b/arch/x86/kernel/cpu/sgx/encls.h
@@ -11,26 +11,8 @@
 #include <asm/traps.h>
 #include "sgx.h"
 
-/**
- * ENCLS_FAULT_FLAG - flag signifying an ENCLS return code is a trapnr
- *
- * ENCLS has its own (positive value) error codes and also generates
- * ENCLS specific #GP and #PF faults.  And the ENCLS values get munged
- * with system error codes as everything percolates back up the stack.
- * Unfortunately (for us), we need to precisely identify each unique
- * error code, e.g. the action taken if EWB fails varies based on the
- * type of fault and on the exact SGX error code, i.e. we can't simply
- * convert all faults to -EFAULT.
- *
- * To make all three error types coexist, we set bit 30 to identify an
- * ENCLS fault.  Bit 31 (technically bits N:31) is used to differentiate
- * between positive (faults and SGX error codes) and negative (system
- * error codes) values.
- */
-#define ENCLS_FAULT_FLAG 0x40000000
-
 /* Retrieve the encoded trapnr from the specified return code. */
-#define ENCLS_TRAPNR(r) ((r) & ~ENCLS_FAULT_FLAG)
+#define ENCLS_TRAPNR(r) ((r) & ~SGX_ENCLS_FAULT_FLAG)
 
 /* Issue a WARN() about an ENCLS function. */
 #define ENCLS_WARN(r, name) {						  \
@@ -50,7 +32,7 @@
  */
 static inline bool encls_faulted(int ret)
 {
-	return ret & ENCLS_FAULT_FLAG;
+	return ret & SGX_ENCLS_FAULT_FLAG;
 }
 
 /**
@@ -88,11 +70,7 @@ static inline bool encls_failed(int ret)
 	asm volatile(						\
 	"1: .byte 0x0f, 0x01, 0xcf;\n\t"			\
 	"2:\n"							\
-	".section .fixup,\"ax\"\n"				\
-	"3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n"	\
-	"   jmp 2b\n"						\
-	".previous\n"						\
-	_ASM_EXTABLE_FAULT(1b, 3b)				\
+	_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX)		\
 	: "=a"(ret)						\
 	: "a"(rax), inputs					\
 	: "memory", "cc");					\
@@ -127,7 +105,7 @@ static inline bool encls_failed(int ret)
  *
  * Return:
  *   0 on success,
- *   trapnr with ENCLS_FAULT_FLAG set on fault
+ *   trapnr with SGX_ENCLS_FAULT_FLAG set on fault
  */
 #define __encls_N(rax, rbx_out, inputs...)			\
 	({							\
@@ -136,11 +114,7 @@ static inline bool encls_failed(int ret)
 	"1: .byte 0x0f, 0x01, 0xcf;\n\t"			\
 	"   xor %%eax,%%eax;\n"					\
 	"2:\n"							\
-	".section .fixup,\"ax\"\n"				\
-	"3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n"	\
-	"   jmp 2b\n"						\
-	".previous\n"						\
-	_ASM_EXTABLE_FAULT(1b, 3b)				\
+	_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX)		\
 	: "=a"(ret), "=b"(rbx_out)				\
 	: "a"(rax), inputs					\
 	: "memory");						\