Merge tag 'x86_entry_for_7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry code updates from Dave Hansen:
 "This is entirely composed of a set of long overdue VDSO cleanups. They
  makes the VDSO build much more logical and zap quite a bit of old
  cruft.

  It also results in a coveted net-code-removal diffstat"

* tag 'x86_entry_for_7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/vdso: Add vdso2c to .gitignore
  x86/entry/vdso32: Omit '.cfi_offset eflags' for LLVM < 16
  MAINTAINERS: Adjust vdso file entry in INTEL SGX
  x86/entry/vdso/selftest: Update location of vgetrandom-chacha.S
  x86/entry/vdso: Fix filtering of vdso compiler flags
  x86/entry/vdso: Update the object paths for "make vdso_install"
  x86/entry/vdso32: When using int $0x80, use it directly
  x86/cpufeature: Replace X86_FEATURE_SYSENTER32 with X86_FEATURE_SYSFAST32
  x86/vdso: Abstract out vdso system call internals
  x86/entry/vdso: Include GNU_PROPERTY and GNU_STACK PHDRs
  x86/entry/vdso32: Remove open-coded DWARF in sigreturn.S
  x86/entry/vdso32: Remove SYSCALL_ENTER_KERNEL macro in sigreturn.S
  x86/entry/vdso32: Don't rely on int80_landing_pad for adjusting ip
  x86/entry/vdso: Refactor the vdso build
  x86/entry/vdso: Move vdso2c to arch/x86/tools
  x86/entry/vdso: Rename vdso_image_* to vdso*_image

Author: torvalds

MAINTAINERS

@@ -13032,7 +13032,7 @@ S:	Supported
 Q:	https://patchwork.kernel.org/project/intel-sgx/list/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/sgx
 F:	Documentation/arch/x86/sgx.rst
-F:	arch/x86/entry/vdso/vsgx.S
+F:	arch/x86/entry/vdso/vdso64/vsgx.S
 F:	arch/x86/include/asm/sgx.h
 F:	arch/x86/include/uapi/asm/sgx.h
 F:	arch/x86/kernel/cpu/sgx/*

arch/x86/Kconfig.cpufeatures

@@ -56,6 +56,10 @@ config X86_REQUIRED_FEATURE_MOVBE
 	def_bool y
 	depends on MATOM
 
+config X86_REQUIRED_FEATURE_SYSFAST32
+	def_bool y
+	depends on X86_64 && !X86_FRED
+
 config X86_REQUIRED_FEATURE_CPUID
 	def_bool y
 	depends on X86_64
@@ -120,6 +124,10 @@ config X86_DISABLED_FEATURE_CENTAUR_MCR
 	def_bool y
 	depends on X86_64
 
+config X86_DISABLED_FEATURE_SYSCALL32
+	def_bool y
+	depends on !X86_64
+
 config X86_DISABLED_FEATURE_PCID
 	def_bool y
 	depends on !X86_64

arch/x86/Makefile

@@ -252,7 +252,7 @@ endif
 
 
 archscripts: scripts_basic
-	$(Q)$(MAKE) $(build)=arch/x86/tools relocs
+	$(Q)$(MAKE) $(build)=arch/x86/tools relocs vdso2c
 
 ###
 # Syscall table generation
@@ -318,9 +318,9 @@ PHONY += install
 install:
 	$(call cmd,install)
 
-vdso-install-$(CONFIG_X86_64)		+= arch/x86/entry/vdso/vdso64.so.dbg
-vdso-install-$(CONFIG_X86_X32_ABI)	+= arch/x86/entry/vdso/vdsox32.so.dbg
-vdso-install-$(CONFIG_COMPAT_32)	+= arch/x86/entry/vdso/vdso32.so.dbg
+vdso-install-$(CONFIG_X86_64)	   += arch/x86/entry/vdso/vdso64/vdso64.so.dbg
+vdso-install-$(CONFIG_X86_X32_ABI) += arch/x86/entry/vdso/vdso64/vdsox32.so.dbg
+vdso-install-$(CONFIG_COMPAT_32)   += arch/x86/entry/vdso/vdso32/vdso32.so.dbg
 
 archprepare: checkbin
 checkbin:

arch/x86/entry/syscall_32.c

@@ -319,7 +319,7 @@ __visible noinstr bool do_fast_syscall_32(struct pt_regs *regs)
 	 * convention.  Adjust regs so it looks like we entered using int80.
 	 */
 	unsigned long landing_pad = (unsigned long)current->mm->context.vdso +
-					vdso_image_32.sym_int80_landing_pad;
+					vdso32_image.sym_int80_landing_pad;
 
 	/*
 	 * SYSENTER loses EIP, and even SYSCALL32 needs us to skip forward

arch/x86/entry/vdso/.gitignore

@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
-vdso.lds
-vdsox32.lds
-vdso32-syscall-syms.lds
-vdso32-sysenter-syms.lds
-vdso32-int80-syms.lds
-vdso-image-*.c
-vdso2c
+*.lds
+*.so
+*.so.dbg
+vdso*-image.c

arch/x86/entry/vdso/Makefile

@@ -3,160 +3,10 @@
 # Building vDSO images for x86.
 #
 
-# Include the generic Makefile to check the built vDSO:
-include $(srctree)/lib/vdso/Makefile.include
+# Regular kernel objects
+obj-y				:= vma.o extable.o
+obj-$(CONFIG_COMPAT_32)		+= vdso32-setup.o
 
-# Files to link into the vDSO:
-vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vgetrandom.o vgetrandom-chacha.o
-vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o
-vobjs32-y += vdso32/vclock_gettime.o vdso32/vgetcpu.o
-vobjs-$(CONFIG_X86_SGX)	+= vsgx.o
-
-# Files to link into the kernel:
-obj-y						+= vma.o extable.o
-
-# vDSO images to build:
-obj-$(CONFIG_X86_64)				+= vdso-image-64.o
-obj-$(CONFIG_X86_X32_ABI)			+= vdso-image-x32.o
-obj-$(CONFIG_COMPAT_32)				+= vdso-image-32.o vdso32-setup.o
-
-vobjs := $(addprefix $(obj)/, $(vobjs-y))
-vobjs32 := $(addprefix $(obj)/, $(vobjs32-y))
-
-$(obj)/vdso.o: $(obj)/vdso.so
-
-targets += vdso.lds $(vobjs-y)
-targets += vdso32/vdso32.lds $(vobjs32-y)
-
-targets += $(foreach x, 64 x32 32, vdso-image-$(x).c vdso$(x).so vdso$(x).so.dbg)
-
-CPPFLAGS_vdso.lds += -P -C
-
-VDSO_LDFLAGS_vdso.lds = -m elf_x86_64 -soname linux-vdso.so.1 \
-			-z max-page-size=4096
-
-$(obj)/vdso64.so.dbg: $(obj)/vdso.lds $(vobjs) FORCE
-	$(call if_changed,vdso_and_check)
-
-HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/$(SUBARCH)/include/uapi
-hostprogs += vdso2c
-
-quiet_cmd_vdso2c = VDSO2C  $@
-      cmd_vdso2c = $(obj)/vdso2c $< $(<:%.dbg=%) $@
-
-$(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE
-	$(call if_changed,vdso2c)
-
-#
-# Don't omit frame pointers for ease of userspace debugging, but do
-# optimize sibling calls.
-#
-CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
-       $(filter -g%,$(KBUILD_CFLAGS)) -fno-stack-protector \
-       -fno-omit-frame-pointer -foptimize-sibling-calls \
-       -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
-
-ifdef CONFIG_MITIGATION_RETPOLINE
-ifneq ($(RETPOLINE_VDSO_CFLAGS),)
-  CFL += $(RETPOLINE_VDSO_CFLAGS)
-endif
-endif
-
-$(vobjs): KBUILD_CFLAGS := $(filter-out $(PADDING_CFLAGS) $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(RANDSTRUCT_CFLAGS) $(KSTACK_ERASE_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
-$(vobjs): KBUILD_AFLAGS += -DBUILD_VDSO
-
-#
-# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
-#
-CFLAGS_REMOVE_vclock_gettime.o = -pg
-CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
-CFLAGS_REMOVE_vgetcpu.o = -pg
-CFLAGS_REMOVE_vdso32/vgetcpu.o = -pg
-CFLAGS_REMOVE_vsgx.o = -pg
-CFLAGS_REMOVE_vgetrandom.o = -pg
-
-#
-# X32 processes use x32 vDSO to access 64bit kernel data.
-#
-# Build x32 vDSO image:
-# 1. Compile x32 vDSO as 64bit.
-# 2. Convert object files to x32.
-# 3. Build x32 VDSO image with x32 objects, which contains 64bit codes
-# so that it can reach 64bit address space with 64bit pointers.
-#
-
-CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds)
-VDSO_LDFLAGS_vdsox32.lds = -m elf32_x86_64 -soname linux-vdso.so.1 \
-			   -z max-page-size=4096
-
-# x32-rebranded versions
-vobjx32s-y := $(vobjs-y:.o=-x32.o)
-
-# same thing, but in the output directory
-vobjx32s := $(addprefix $(obj)/, $(vobjx32s-y))
-
-# Convert 64bit object file to x32 for x32 vDSO.
-quiet_cmd_x32 = X32     $@
-      cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@
-
-$(obj)/%-x32.o: $(obj)/%.o FORCE
-	$(call if_changed,x32)
-
-targets += vdsox32.lds $(vobjx32s-y)
-
-$(obj)/%.so: OBJCOPYFLAGS := -S --remove-section __ex_table
-$(obj)/%.so: $(obj)/%.so.dbg FORCE
-	$(call if_changed,objcopy)
-
-$(obj)/vdsox32.so.dbg: $(obj)/vdsox32.lds $(vobjx32s) FORCE
-	$(call if_changed,vdso_and_check)
-
-CPPFLAGS_vdso32/vdso32.lds = $(CPPFLAGS_vdso.lds)
-VDSO_LDFLAGS_vdso32.lds = -m elf_i386 -soname linux-gate.so.1
-
-KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO
-$(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
-$(obj)/vdso32.so.dbg: asflags-$(CONFIG_X86_64) += -m32
-
-KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
-KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(RANDSTRUCT_CFLAGS),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(KSTACK_ERASE_CFLAGS),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_CFI),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 := $(filter-out $(PADDING_CFLAGS),$(KBUILD_CFLAGS_32))
-KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
-KBUILD_CFLAGS_32 += -fno-stack-protector
-KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
-KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
-KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
-KBUILD_CFLAGS_32 += -DBUILD_VDSO
-
-ifdef CONFIG_MITIGATION_RETPOLINE
-ifneq ($(RETPOLINE_VDSO_CFLAGS),)
-  KBUILD_CFLAGS_32 += $(RETPOLINE_VDSO_CFLAGS)
-endif
-endif
-
-$(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
-
-$(obj)/vdso32.so.dbg: $(obj)/vdso32/vdso32.lds $(vobjs32) FORCE
-	$(call if_changed,vdso_and_check)
-
-#
-# The DSO images are built using a special linker script.
-#
-quiet_cmd_vdso = VDSO    $@
-      cmd_vdso = $(LD) -o $@ \
-		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
-		       -T $(filter %.lds,$^) $(filter %.o,$^)
-
-VDSO_LDFLAGS = -shared --hash-style=both --build-id=sha1 --no-undefined \
-	$(call ld-option, --eh-frame-hdr) -Bsymbolic -z noexecstack
-
-quiet_cmd_vdso_and_check = VDSO    $@
-      cmd_vdso_and_check = $(cmd_vdso); $(cmd_vdso_check)
+# vDSO directories
+obj-$(CONFIG_X86_64)		+= vdso64/
+obj-$(CONFIG_COMPAT_32)		+= vdso32/

arch/x86/entry/vdso/common/Makefile.include

@@ -0,0 +1,89 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Building vDSO images for x86.
+#
+
+# Include the generic Makefile to check the built vDSO:
+include $(srctree)/lib/vdso/Makefile.include
+
+obj-y    += $(foreach x,$(vdsos-y),vdso$(x)-image.o)
+
+targets  += $(foreach x,$(vdsos-y),vdso$(x)-image.c vdso$(x).so vdso$(x).so.dbg vdso$(x).lds)
+targets  += $(vobjs-y)
+
+# vobjs-y with $(obj)/ prepended
+vobjs := $(addprefix $(obj)/,$(vobjs-y))
+
+# Options for vdso*.lds
+CPPFLAGS_VDSO_LDS := -P -C -I$(src)/..
+$(obj)/%.lds : KBUILD_CPPFLAGS += $(CPPFLAGS_VDSO_LDS)
+
+#
+# Options from KBUILD_[AC]FLAGS that should *NOT* be kept
+#
+flags-remove-y += \
+	-D__KERNEL__ -mcmodel=kernel -mregparm=3 \
+	-fno-pic -fno-PIC -fno-pie -fno-PIE \
+	-mfentry -pg \
+	$(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(KSTACK_ERASE_CFLAGS) \
+	$(RETPOLINE_CFLAGS) $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \
+	$(PADDING_CFLAGS)
+
+#
+# Don't omit frame pointers for ease of userspace debugging, but do
+# optimize sibling calls.
+#
+flags-y += -D__DISABLE_EXPORTS
+flags-y += -DDISABLE_BRANCH_PROFILING
+flags-y += -DBUILD_VDSO
+flags-y += -I$(src)/.. -I$(srctree)
+flags-y += -O2 -fpic
+flags-y += -fno-stack-protector
+flags-y += -fno-omit-frame-pointer
+flags-y += -foptimize-sibling-calls
+flags-y += -fasynchronous-unwind-tables
+
+# Reset cf protections enabled by compiler default
+flags-y += $(call cc-option, -fcf-protection=none)
+flags-$(X86_USER_SHADOW_STACK) += $(call cc-option, -fcf-protection=return)
+# When user space IBT is supported, enable this.
+# flags-$(CONFIG_USER_IBT) += $(call cc-option, -fcf-protection=branch)
+
+flags-$(CONFIG_MITIGATION_RETPOLINE) += $(RETPOLINE_VDSO_CFLAGS)
+
+# These need to be conditional on $(vobjs) as they do not apply to
+# the output vdso*-image.o files which are standard kernel objects.
+$(vobjs) : KBUILD_AFLAGS := \
+	$(filter-out $(flags-remove-y),$(KBUILD_AFLAGS)) $(flags-y)
+$(vobjs) : KBUILD_CFLAGS := \
+	$(filter-out $(flags-remove-y),$(KBUILD_CFLAGS)) $(flags-y)
+
+#
+# The VDSO images are built using a special linker script.
+#
+VDSO_LDFLAGS := -shared --hash-style=both --build-id=sha1 --no-undefined \
+	$(call ld-option, --eh-frame-hdr) -Bsymbolic -z noexecstack
+
+quiet_cmd_vdso = VDSO    $@
+      cmd_vdso = $(LD) -o $@ \
+		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$*) \
+		       -T $(filter %.lds,$^) $(filter %.o,$^)
+quiet_cmd_vdso_and_check = VDSO    $@
+      cmd_vdso_and_check = $(cmd_vdso); $(cmd_vdso_check)
+
+$(obj)/vdso%.so.dbg: $(obj)/vdso%.lds FORCE
+	$(call if_changed,vdso_and_check)
+
+$(obj)/%.so: OBJCOPYFLAGS := -S --remove-section __ex_table
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+VDSO2C = $(objtree)/arch/x86/tools/vdso2c
+
+quiet_cmd_vdso2c = VDSO2C  $@
+      cmd_vdso2c = $(VDSO2C) $< $(<:%.dbg=%) $@
+
+$(obj)/%-image.c: $(obj)/%.so.dbg $(obj)/%.so $(VDSO2C) FORCE
+	$(call if_changed,vdso2c)
+
+$(obj)/%-image.o: $(obj)/%-image.c

arch/x86/entry/vdso/vdso-note.S arch/x86/entry/vdso/common/note.Sarch/x86/entry/vdso/vdso-note.S renamed to arch/x86/entry/vdso/common/note.S

@@ -1,13 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
  * Here we can supply some information useful to userland.
  */
 
 #include <linux/build-salt.h>
-#include <linux/uts.h>
 #include <linux/version.h>
 #include <linux/elfnote.h>
 
+/* Ideally this would use UTS_NAME, but using a quoted string here
+   doesn't work. Remember to change this when changing the
+   kernel's name. */
 ELFNOTE_START(Linux, 0, "a")
 	.long LINUX_VERSION_CODE
 ELFNOTE_END