Merge commit 'upstream-x86-entry' into WIP.x86/mm

Pull in a minimal set of v4.15 entry code changes, for a base for the MM isolation patches.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Documentation/x86/orc-unwinder.txt

@@ -4,7 +4,7 @@ ORC unwinder
 Overview
 --------
 
-The kernel CONFIG_ORC_UNWINDER option enables the ORC unwinder, which is
+The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is
 similar in concept to a DWARF unwinder.  The difference is that the
 format of the ORC data is much simpler than DWARF, which in turn allows
 the ORC unwinder to be much simpler and faster.

Makefile

@@ -934,8 +934,8 @@ ifdef CONFIG_STACK_VALIDATION
   ifeq ($(has_libelf),1)
     objtool_target := tools/objtool FORCE
   else
-    ifdef CONFIG_ORC_UNWINDER
-      $(error "Cannot generate ORC metadata for CONFIG_ORC_UNWINDER=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
+    ifdef CONFIG_UNWINDER_ORC
+      $(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
     else
       $(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
     endif

arch/x86/Kconfig

@@ -171,7 +171,7 @@ config X86
 	select HAVE_PERF_USER_STACK_DUMP
 	select HAVE_RCU_TABLE_FREE
 	select HAVE_REGS_AND_STACK_ACCESS_API
-	select HAVE_RELIABLE_STACKTRACE		if X86_64 && FRAME_POINTER_UNWINDER && STACK_VALIDATION
+	select HAVE_RELIABLE_STACKTRACE		if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
 	select HAVE_STACK_VALIDATION		if X86_64
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_UNSTABLE_SCHED_CLOCK

arch/x86/Kconfig.debug

@@ -359,28 +359,14 @@ config PUNIT_ATOM_DEBUG
 
 choice
 	prompt "Choose kernel unwinder"
-	default FRAME_POINTER_UNWINDER
+	default UNWINDER_ORC if X86_64
+	default UNWINDER_FRAME_POINTER if X86_32
 	---help---
 	  This determines which method will be used for unwinding kernel stack
 	  traces for panics, oopses, bugs, warnings, perf, /proc/<pid>/stack,
 	  livepatch, lockdep, and more.
 
-config FRAME_POINTER_UNWINDER
-	bool "Frame pointer unwinder"
-	select FRAME_POINTER
-	---help---
-	  This option enables the frame pointer unwinder for unwinding kernel
-	  stack traces.
-
-	  The unwinder itself is fast and it uses less RAM than the ORC
-	  unwinder, but the kernel text size will grow by ~3% and the kernel's
-	  overall performance will degrade by roughly 5-10%.
-
-	  This option is recommended if you want to use the livepatch
-	  consistency model, as this is currently the only way to get a
-	  reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
-
-config ORC_UNWINDER
+config UNWINDER_ORC
 	bool "ORC unwinder"
 	depends on X86_64
 	select STACK_VALIDATION
@@ -396,7 +382,22 @@ config ORC_UNWINDER
 	  Enabling this option will increase the kernel's runtime memory usage
 	  by roughly 2-4MB, depending on your kernel config.
 
-config GUESS_UNWINDER
+config UNWINDER_FRAME_POINTER
+	bool "Frame pointer unwinder"
+	select FRAME_POINTER
+	---help---
+	  This option enables the frame pointer unwinder for unwinding kernel
+	  stack traces.
+
+	  The unwinder itself is fast and it uses less RAM than the ORC
+	  unwinder, but the kernel text size will grow by ~3% and the kernel's
+	  overall performance will degrade by roughly 5-10%.
+
+	  This option is recommended if you want to use the livepatch
+	  consistency model, as this is currently the only way to get a
+	  reliable stack trace (CONFIG_HAVE_RELIABLE_STACKTRACE).
+
+config UNWINDER_GUESS
 	bool "Guess unwinder"
 	depends on EXPERT
 	---help---
@@ -411,7 +412,7 @@ config GUESS_UNWINDER
 endchoice
 
 config FRAME_POINTER
-	depends on !ORC_UNWINDER && !GUESS_UNWINDER
+	depends on !UNWINDER_ORC && !UNWINDER_GUESS
 	bool
 
 endmenu

arch/x86/configs/tiny.config

@@ -1,5 +1,5 @@
 CONFIG_NOHIGHMEM=y
 # CONFIG_HIGHMEM4G is not set
 # CONFIG_HIGHMEM64G is not set
-CONFIG_GUESS_UNWINDER=y
-# CONFIG_FRAME_POINTER_UNWINDER is not set
+CONFIG_UNWINDER_GUESS=y
+# CONFIG_UNWINDER_FRAME_POINTER is not set

arch/x86/configs/x86_64_defconfig

@@ -299,6 +299,7 @@ CONFIG_DEBUG_STACKOVERFLOW=y
 # CONFIG_DEBUG_RODATA_TEST is not set
 CONFIG_DEBUG_BOOT_PARAMS=y
 CONFIG_OPTIMIZE_INLINING=y
+CONFIG_UNWINDER_ORC=y
 CONFIG_SECURITY=y
 CONFIG_SECURITY_NETWORK=y
 CONFIG_SECURITY_SELINUX=y

arch/x86/entry/calling.h

@@ -142,56 +142,25 @@ For 32-bit we have the following conventions - kernel is built with
 	UNWIND_HINT_REGS offset=\offset
 	.endm
 
-	.macro RESTORE_EXTRA_REGS offset=0
-	movq 0*8+\offset(%rsp), %r15
-	movq 1*8+\offset(%rsp), %r14
-	movq 2*8+\offset(%rsp), %r13
-	movq 3*8+\offset(%rsp), %r12
-	movq 4*8+\offset(%rsp), %rbp
-	movq 5*8+\offset(%rsp), %rbx
-	UNWIND_HINT_REGS offset=\offset extra=0
-	.endm
-
-	.macro RESTORE_C_REGS_HELPER rstor_rax=1, rstor_rcx=1, rstor_r11=1, rstor_r8910=1, rstor_rdx=1
-	.if \rstor_r11
-	movq 6*8(%rsp), %r11
-	.endif
-	.if \rstor_r8910
-	movq 7*8(%rsp), %r10
-	movq 8*8(%rsp), %r9
-	movq 9*8(%rsp), %r8
-	.endif
-	.if \rstor_rax
-	movq 10*8(%rsp), %rax
-	.endif
-	.if \rstor_rcx
-	movq 11*8(%rsp), %rcx
-	.endif
-	.if \rstor_rdx
-	movq 12*8(%rsp), %rdx
-	.endif
-	movq 13*8(%rsp), %rsi
-	movq 14*8(%rsp), %rdi
-	UNWIND_HINT_IRET_REGS offset=16*8
-	.endm
-	.macro RESTORE_C_REGS
-	RESTORE_C_REGS_HELPER 1,1,1,1,1
-	.endm
-	.macro RESTORE_C_REGS_EXCEPT_RAX
-	RESTORE_C_REGS_HELPER 0,1,1,1,1
-	.endm
-	.macro RESTORE_C_REGS_EXCEPT_RCX
-	RESTORE_C_REGS_HELPER 1,0,1,1,1
-	.endm
-	.macro RESTORE_C_REGS_EXCEPT_R11
-	RESTORE_C_REGS_HELPER 1,1,0,1,1
-	.endm
-	.macro RESTORE_C_REGS_EXCEPT_RCX_R11
-	RESTORE_C_REGS_HELPER 1,0,0,1,1
-	.endm
-
-	.macro REMOVE_PT_GPREGS_FROM_STACK addskip=0
-	subq $-(15*8+\addskip), %rsp
+	.macro POP_EXTRA_REGS
+	popq %r15
+	popq %r14
+	popq %r13
+	popq %r12
+	popq %rbp
+	popq %rbx
+	.endm
+
+	.macro POP_C_REGS
+	popq %r11
+	popq %r10
+	popq %r9
+	popq %r8
+	popq %rax
+	popq %rcx
+	popq %rdx
+	popq %rsi
+	popq %rdi
 	.endm
 
 	.macro icebp