aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/vdso/Makefile
blob: c580d1210ffe98866aa72582a5a56c81089362a8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
#
# Building vDSO images for x86.
#

KBUILD_CFLAGS += $(DISABLE_LTO)

VDSO64-$(CONFIG_X86_64)		:= y
VDSOX32-$(CONFIG_X86_X32_ABI)	:= y
VDSO32-$(CONFIG_X86_32)		:= y
VDSO32-$(CONFIG_COMPAT)		:= y

vdso-install-$(VDSO64-y)	+= vdso.so
vdso-install-$(VDSOX32-y)	+= vdsox32.so
vdso-install-$(VDSO32-y)	+= $(vdso32-images)


# files to link into the vdso
vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o

vobjs-$(VDSOX32-y) += $(vobjx32s-compat)

# Filter out x32 objects.
vobj64s := $(filter-out $(vobjx32s-compat),$(vobjs-y))

# files to link into kernel
obj-y				+= vma.o
obj-$(VDSO64-y)			+= vdso.o
obj-$(VDSOX32-y)		+= vdsox32.o
obj-$(VDSO32-y)			+= vdso32.o vdso32-setup.o

vobjs := $(foreach F,$(vobj64s),$(obj)/$F)

$(obj)/vdso.o: $(obj)/vdso.so

targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)

export CPPFLAGS_vdso.lds += -P -C

VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
			-Wl,--no-undefined \
			-Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 \
			$(DISABLE_LTO)

$(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so

$(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
	$(call if_changed,vdso)

$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
	$(call if_changed,objcopy)

#
# 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)) $(call cc-option, -fno-stack-protector) \
       -fno-omit-frame-pointer -foptimize-sibling-calls

$(vobjs): KBUILD_CFLAGS += $(CFL)

#
# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
#
CFLAGS_REMOVE_vdso-note.o = -pg
CFLAGS_REMOVE_vclock_gettime.o = -pg
CFLAGS_REMOVE_vgetcpu.o = -pg
CFLAGS_REMOVE_vvar.o = -pg

targets += vdso-syms.lds
obj-$(VDSO64-y)			+= vdso-syms.lds

#
# Match symbols in the DSO that look like VDSO*; produce a file of constants.
#
sed-vdsosym := -e 's/^00*/0/' \
	-e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p'
quiet_cmd_vdsosym = VDSOSYM $@
define cmd_vdsosym
	$(NM) $< | LC_ALL=C sed -n $(sed-vdsosym) | LC_ALL=C sort > $@
endef

$(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
	$(call if_changed,vdsosym)

#
# 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.
#

targets += vdsox32-syms.lds
obj-$(VDSOX32-y)		+= vdsox32-syms.lds

CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds)
VDSO_LDFLAGS_vdsox32.lds = -Wl,-m,elf32_x86_64 \
			   -Wl,-soname=linux-vdso.so.1 \
			   -Wl,-z,max-page-size=4096 \
			   -Wl,-z,common-page-size=4096

vobjx32s-y := $(vobj64s:.o=-x32.o)
vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F)

# 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.so vdsox32.so.dbg vdsox32.lds $(vobjx32s-y)

$(obj)/vdsox32.o: $(src)/vdsox32.S $(obj)/vdsox32.so

$(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE
	$(call if_changed,vdso)

#
# Build multiple 32-bit vDSO images to choose from at boot time.
#
obj-$(VDSO32-y)			+= vdso32-syms.lds
vdso32.so-$(VDSO32-y)		+= int80
vdso32.so-$(CONFIG_COMPAT)	+= syscall
vdso32.so-$(VDSO32-y)		+= sysenter

vdso32-images			= $(vdso32.so-y:%=vdso32-%.so)

CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1

# This makes sure the $(obj) subdirectory exists even though vdso32/
# is not a kbuild sub-make subdirectory.
override obj-dirs = $(dir $(obj)) $(obj)/vdso32/

targets += vdso32/vdso32.lds
targets += $(vdso32-images) $(vdso32-images:=.dbg)
targets += vdso32/note.o vdso32/vclock_gettime.o $(vdso32.so-y:%=vdso32/%.o)

extra-y	+= $(vdso32-images)

$(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%)

KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
$(vdso32-images:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
$(vdso32-images:%=$(obj)/%.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 += -m32 -msoft-float -mregparm=0 -fpic
KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
$(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)

$(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \
				 $(obj)/vdso32/vdso32.lds \
				 $(obj)/vdso32/vclock_gettime.o \
				 $(obj)/vdso32/note.o \
				 $(obj)/vdso32/%.o
	$(call if_changed,vdso)

# Make vdso32-*-syms.lds from each image, and then make sure they match.
# The only difference should be that some do not define VDSO32_SYSENTER_RETURN.

targets += vdso32-syms.lds $(vdso32.so-y:%=vdso32-%-syms.lds)

quiet_cmd_vdso32sym = VDSOSYM $@
define cmd_vdso32sym
	if LC_ALL=C sort -u $(filter-out FORCE,$^) > $(@D)/.tmp_$(@F) && \
	   $(foreach H,$(filter-out FORCE,$^),\
		     if grep -q VDSO32_SYSENTER_RETURN $H; \
		     then diff -u $(@D)/.tmp_$(@F) $H; \
		     else sed /VDSO32_SYSENTER_RETURN/d $(@D)/.tmp_$(@F) | \
			  diff -u - $H; fi &&) : ;\
	then mv -f $(@D)/.tmp_$(@F) $@; \
	else rm -f $(@D)/.tmp_$(@F); exit 1; \
	fi
endef

$(obj)/vdso32-syms.lds: $(vdso32.so-y:%=$(obj)/vdso32-%-syms.lds) FORCE
	$(call if_changed,vdso32sym)

#
# The DSO images are built using a special linker script.
#
quiet_cmd_vdso = VDSO    $@
      cmd_vdso = $(CC) -nostdlib -o $@ \
		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
		       -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'

VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \
		$(LTO_CFLAGS)
GCOV_PROFILE := n

#
# Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
#
quiet_cmd_vdso_install = INSTALL $@
      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
	@mkdir -p $(MODLIB)/vdso
	$(call cmd,vdso_install)

PHONY += vdso_install $(vdso-install-y)
vdso_install: $(vdso-install-y)

clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80*