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

1 files changed, 89 insertions, 0 deletions

diff --git a/arch/x86/entry/vdso/common/Makefile.include b/arch/x86/entry/vdso/common/Makefile.include
new file mode 100644
index 000000000000..687b3d89b40d
--- /dev/null
+++ b/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