arch/x86/um/vdso/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # Building vDSO images for x86.
   4 #
   5
   6 # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
   7 KCOV_INSTRUMENT                := n
   8
   9 VDSO64-y                := y
  10
  11 vdso-install-$(VDSO64-y)        += vdso.so
  12
  13
  14 # files to link into the vdso
  15 vobjs-y := vdso-note.o um_vdso.o
  16
  17 # files to link into kernel
  18 obj-$(VDSO64-y)                 += vdso.o vma.o
  19
  20 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
  21
  22 $(obj)/vdso.o: $(obj)/vdso.so
  23
  24 targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)
  25
  26 CPPFLAGS_vdso.lds += -P -C
  27
  28 VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
  29        -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
  30
  31 $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
  32
  33 $(obj)/vdso.so.dbg: $(obj)/vdso.lds $(vobjs) FORCE
  34         $(call if_changed,vdso)
  35
  36 $(obj)/%.so: OBJCOPYFLAGS := -S
  37 $(obj)/%.so: $(obj)/%.so.dbg FORCE
  38         $(call if_changed,objcopy)
  39
  40 #
  41 # Don't omit frame pointers for ease of userspace debugging, but do
  42 # optimize sibling calls.
  43 #
  44 CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
  45        $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
  46        -fno-omit-frame-pointer -foptimize-sibling-calls
  47
  48 $(vobjs): KBUILD_CFLAGS += $(CFL)
  49
  50 #
  51 # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
  52 #
  53 CFLAGS_REMOVE_vdso-note.o = -pg -fprofile-arcs -ftest-coverage
  54 CFLAGS_REMOVE_um_vdso.o = -pg -fprofile-arcs -ftest-coverage
  55
  56 #
  57 # The DSO images are built using a special linker script.
  58 #
  59 quiet_cmd_vdso = VDSO    $@
  60       cmd_vdso = $(CC) -nostdlib -o $@ \
  61                        $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
  62                        -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
  63                  sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
  64
  65 VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
  66 GCOV_PROFILE := n
  67
  68 #
  69 # Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
  70 #
  71 quiet_cmd_vdso_install = INSTALL $@
  72       cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
  73 $(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
  74         @mkdir -p $(MODLIB)/vdso
  75         $(call cmd,vdso_install)
  76
  77 PHONY += vdso_install $(vdso-install-y)
  78 vdso_install: $(vdso-install-y)