To fully build UML use:
$ make -C tools/um
which will generate tools/lkl/linux as the UML executable. To
statically compiled UML use:
$ make -C tools/lkl UML_STATIC=y
Signed-off-by: Octavian Purdila <tavi@xxxxxxxxx>
Signed-off-by: Hajime Tazaki <thehajime@xxxxxxxxx>
---
arch/um/Kconfig | 12 +--
arch/um/Makefile | 14 ++-
arch/um/include/asm/common.lds.S | 99 ------------------
arch/um/kernel/dyn.lds.S | 171 -------------------------------
arch/um/kernel/uml.lds.S | 115 ---------------------
arch/um/kernel/vmlinux.lds.S | 91 ++++++++++++++--
scripts/link-vmlinux.sh | 42 +++-----
tools/um/Makefile | 72 +++++++++++++
tools/um/Targets | 4 +
tools/um/uml/Build | 0
10 files changed, 184 insertions(+), 436 deletions(-)
delete mode 100644 arch/um/include/asm/common.lds.S
delete mode 100644 arch/um/kernel/dyn.lds.S
delete mode 100644 arch/um/kernel/uml.lds.S
create mode 100644 tools/um/Makefile
create mode 100644 tools/um/Targets
create mode 100644 tools/um/uml/Build
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index eb51fec75948..e41d31d0d875 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -20,6 +20,7 @@ config UML
select GENERIC_CLOCKEVENTS
select HAVE_GCC_PLUGINS
select TTY # Needed for line.c
+ select MODULE_REL_CRCS if MODVERSIONS
config MMU
bool
@@ -79,17 +80,6 @@ config STATIC_LINK
NOTE: This option is incompatible with some networking features which
depend on features that require being dynamically loaded (like NSS).
-config LD_SCRIPT_STATIC
- bool
- default y
- depends on STATIC_LINK
-
-config LD_SCRIPT_DYN
- bool
- default y
- depends on !LD_SCRIPT_STATIC
- select MODULE_REL_CRCS if MODVERSIONS
-
config HOSTFS
tristate "Host filesystem"
help
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 1cea46ff9bb7..fdfaff4633e8 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -95,14 +95,20 @@ KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
KERNEL_DEFINES = $(strip -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \
-Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES))
KBUILD_CFLAGS += $(KERNEL_DEFINES)
+LDFLAGS_vmlinux += -r
-PHONY += linux
+PHONY += linux.o
-all: linux
+all: linux.o
-linux: vmlinux
+linux.o: vmlinux
@echo ' LINK $@'
- $(Q)ln -f $< $@
+ $(Q)$(OBJCOPY) -R .eh_frame $< $@
+
+install: linux.o
+ @echo " INSTALL $(INSTALL_PATH)/lib/$<"
+ @mkdir -p $(INSTALL_PATH)/lib/
+ @cp $< $(INSTALL_PATH)/lib/
define archhelp
echo '* linux - Binary kernel image (./linux) - for backward'
diff --git a/arch/um/include/asm/common.lds.S b/arch/um/include/asm/common.lds.S
deleted file mode 100644
index eca6c452a41b..000000000000
--- a/arch/um/include/asm/common.lds.S
+++ /dev/null
@@ -1,99 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#include <asm-generic/vmlinux.lds.h>
-
- .fini : { *(.fini) } =0x9090
- _etext = .;
- PROVIDE (etext = .);
-
- . = ALIGN(4096);
- _sdata = .;
- PROVIDE (sdata = .);
-
- RO_DATA(4096)
-
- .unprotected : { *(.unprotected) }
- . = ALIGN(4096);
- PROVIDE (_unprotected_end = .);
-
- . = ALIGN(4096);
- EXCEPTION_TABLE(0)
-
- BUG_TABLE
-
- .uml.setup.init : {
- __uml_setup_start = .;
- *(.uml.setup.init)
- __uml_setup_end = .;
- }
-
- .uml.help.init : {
- __uml_help_start = .;
- *(.uml.help.init)
- __uml_help_end = .;
- }
-
- .uml.postsetup.init : {
- __uml_postsetup_start = .;
- *(.uml.postsetup.init)
- __uml_postsetup_end = .;
- }
-
- .init.setup : {
- INIT_SETUP(0)
- }
-
- PERCPU_SECTION(32)
-
- .initcall.init : {
- INIT_CALLS
- }
-
- .con_initcall.init : {
- CON_INITCALL
- }
-
- .exitcall : {
- __exitcall_begin = .;
- *(.exitcall.exit)
- __exitcall_end = .;
- }
-
- .uml.exitcall : {
- __uml_exitcall_begin = .;
- *(.uml.exitcall.exit)
- __uml_exitcall_end = .;
- }
-
- . = ALIGN(4);
- .altinstructions : {
- __alt_instructions = .;
- *(.altinstructions)
- __alt_instructions_end = .;
- }
- .altinstr_replacement : { *(.altinstr_replacement) }
- /* .exit.text is discard at runtime, not link time, to deal with references
- from .altinstructions and .eh_frame */
- .exit.text : { EXIT_TEXT }
- .exit.data : { *(.exit.data) }
-
- .preinit_array : {
- __preinit_array_start = .;
- *(.preinit_array)
- __preinit_array_end = .;
- }
- .init_array : {
- __init_array_start = .;
- *(.init_array)
- __init_array_end = .;
- }
- .fini_array : {
- __fini_array_start = .;
- *(.fini_array)
- __fini_array_end = .;
- }
-
- . = ALIGN(4096);
- .init.ramfs : {
- INIT_RAM_FS
- }
-
diff --git a/arch/um/kernel/dyn.lds.S b/arch/um/kernel/dyn.lds.S
deleted file mode 100644
index f5001481010c..000000000000
--- a/arch/um/kernel/dyn.lds.S
+++ /dev/null
@@ -1,171 +0,0 @@
-#include <asm/vmlinux.lds.h>
-#include <asm/page.h>
-
-OUTPUT_FORMAT(ELF_FORMAT)
-OUTPUT_ARCH(ELF_ARCH)
-ENTRY(_start)
-jiffies = jiffies_64;
-
-SECTIONS
-{
- PROVIDE (__executable_start = START);
- . = START + SIZEOF_HEADERS;
- .interp : { *(.interp) }
- __binary_start = .;
- . = ALIGN(4096); /* Init code and data */
- _text = .;
- INIT_TEXT_SECTION(PAGE_SIZE)
-
- . = ALIGN(PAGE_SIZE);
-
- /* Read-only sections, merged into text segment: */
- .hash : { *(.hash) }
- .gnu.hash : { *(.gnu.hash) }
- .dynsym : { *(.dynsym) }
- .dynstr : { *(.dynstr) }
- .gnu.version : { *(.gnu.version) }
- .gnu.version_d : { *(.gnu.version_d) }
- .gnu.version_r : { *(.gnu.version_r) }
- .rel.init : { *(.rel.init) }
- .rela.init : { *(.rela.init) }
- .rel.text : { *(.rel.text .rel.text.* .rel.gnu.linkonce.t.*) }
- .rela.text : { *(.rela.text .rela.text.* .rela.gnu.linkonce.t.*) }
- .rel.fini : { *(.rel.fini) }
- .rela.fini : { *(.rela.fini) }
- .rel.rodata : { *(.rel.rodata .rel.rodata.* .rel.gnu.linkonce.r.*) }
- .rela.rodata : { *(.rela.rodata .rela.rodata.* .rela.gnu.linkonce.r.*) }
- .rel.data : { *(.rel.data .rel.data.* .rel.gnu.linkonce.d.*) }
- .rela.data : { *(.rela.data .rela.data.* .rela.gnu.linkonce.d.*) }
- .rel.tdata : { *(.rel.tdata .rel.tdata.* .rel.gnu.linkonce.td.*) }
- .rela.tdata : { *(.rela.tdata .rela.tdata.* .rela.gnu.linkonce.td.*) }
- .rel.tbss : { *(.rel.tbss .rel.tbss.* .rel.gnu.linkonce.tb.*) }
- .rela.tbss : { *(.rela.tbss .rela.tbss.* .rela.gnu.linkonce.tb.*) }
- .rel.ctors : { *(.rel.ctors) }
- .rela.ctors : { *(.rela.ctors) }
- .rel.dtors : { *(.rel.dtors) }
- .rela.dtors : { *(.rela.dtors) }
- .rel.got : { *(.rel.got) }
- .rela.got : { *(.rela.got) }
- .rel.bss : { *(.rel.bss .rel.bss.* .rel.gnu.linkonce.b.*) }
- .rela.bss : { *(.rela.bss .rela.bss.* .rela.gnu.linkonce.b.*) }
- .rel.plt : {
- *(.rel.plt)
- PROVIDE_HIDDEN(__rel_iplt_start = .);
- *(.rel.iplt)
- PROVIDE_HIDDEN(__rel_iplt_end = .);
- }
- .rela.plt : {
- *(.rela.plt)
- PROVIDE_HIDDEN(__rela_iplt_start = .);
- *(.rela.iplt)
- PROVIDE_HIDDEN(__rela_iplt_end = .);
- }
- .init : {
- KEEP (*(.init))
- } =0x90909090
- .plt : { *(.plt) }
- .text : {
- _stext = .;
- TEXT_TEXT
- SCHED_TEXT
- CPUIDLE_TEXT
- LOCK_TEXT
- IRQENTRY_TEXT
- SOFTIRQENTRY_TEXT
- *(.fixup)
- *(.stub .text.* .gnu.linkonce.t.*)
- /* .gnu.warning sections are handled specially by elf32.em. */
- *(.gnu.warning)
-
- . = ALIGN(PAGE_SIZE);
- } =0x90909090
- . = ALIGN(PAGE_SIZE);
- .syscall_stub : {
- __syscall_stub_start = .;
- *(.__syscall_stub*)
- __syscall_stub_end = .;
- }
- .fini : {
- KEEP (*(.fini))
- } =0x90909090
-
- .kstrtab : { *(.kstrtab) }
-
- #include <asm/common.lds.S>
-
- __init_begin = .;
- init.data : { INIT_DATA }
- __init_end = .;
-
- /* Ensure the __preinit_array_start label is properly aligned. We
- could instead move the label definition inside the section, but
- the linker would then create the section even if it turns out to
- be empty, which isn't pretty. */
- . = ALIGN(32 / 8);
- .preinit_array : { *(.preinit_array) }
- .init_array : { *(.init_array) }
- .fini_array : { *(.fini_array) }
- .data : {
- INIT_TASK_DATA(KERNEL_STACK_SIZE)
- . = ALIGN(KERNEL_STACK_SIZE);
- *(.data..init_irqstack)
- DATA_DATA
- *(.data.* .gnu.linkonce.d.*)
- SORT(CONSTRUCTORS)
- }
- .data1 : { *(.data1) }
- .tdata : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
- .tbss : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
- .eh_frame : { KEEP (*(.eh_frame)) }
- .gcc_except_table : { *(.gcc_except_table) }
- .dynamic : { *(.dynamic) }
- .ctors : {
- /* gcc uses crtbegin.o to find the start of
- the constructors, so we make sure it is
- first. Because this is a wildcard, it
- doesn't matter if the user does not
- actually link against crtbegin.o; the
- linker won't look for a file to match a
- wildcard. The wildcard also means that it
- doesn't matter which directory crtbegin.o
- is in. */
- KEEP (*crtbegin.o(.ctors))
- /* We don't want to include the .ctor section from
- from the crtend.o file until after the sorted ctors.
- The .ctor section from the crtend file contains the
- end of ctors marker and it must be last */
- KEEP (*(EXCLUDE_FILE (*crtend.o ) .ctors))
- KEEP (*(SORT(.ctors.*)))
- KEEP (*(.ctors))
- }
- .dtors : {
- KEEP (*crtbegin.o(.dtors))
- KEEP (*(EXCLUDE_FILE (*crtend.o ) .dtors))
- KEEP (*(SORT(.dtors.*)))
- KEEP (*(.dtors))
- }
- .jcr : { KEEP (*(.jcr)) }
- .got : { *(.got.plt) *(.got) }
- _edata = .;
- PROVIDE (edata = .);
- .bss : {
- __bss_start = .;
- *(.dynbss)
- *(.bss .bss.* .gnu.linkonce.b.*)
- *(COMMON)
- /* Align here to ensure that the .bss section occupies space up to
- _end. Align after .bss to ensure correct alignment even if the
- .bss section disappears because there are no input sections. */
- . = ALIGN(32 / 8);
- . = ALIGN(32 / 8);
- }
- __bss_stop = .;
- _end = .;
- PROVIDE (end = .);
-
- STABS_DEBUG
-
- DWARF_DEBUG
-
- DISCARDS
-}
diff --git a/arch/um/kernel/uml.lds.S b/arch/um/kernel/uml.lds.S
deleted file mode 100644
index 3b6dab3d4501..000000000000
--- a/arch/um/kernel/uml.lds.S
+++ /dev/null
@@ -1,115 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#include <asm/vmlinux.lds.h>
-#include <asm/page.h>
-
-OUTPUT_FORMAT(ELF_FORMAT)
-OUTPUT_ARCH(ELF_ARCH)
-ENTRY(_start)
-jiffies = jiffies_64;
-
-SECTIONS
-{
- /* This must contain the right address - not quite the default ELF one.*/
- PROVIDE (__executable_start = START);
- /* Static binaries stick stuff here, like the sigreturn trampoline,
- * invisibly to objdump. So, just make __binary_start equal to the very
- * beginning of the executable, and if there are unmapped pages after this,
- * they are forever unusable.
- */
- __binary_start = START;
-
- . = START + SIZEOF_HEADERS;
- . = ALIGN(PAGE_SIZE);
-
- _text = .;
- INIT_TEXT_SECTION(0)
-
- .text :
- {
- _stext = .;
- TEXT_TEXT
- SCHED_TEXT
- CPUIDLE_TEXT
- LOCK_TEXT
- IRQENTRY_TEXT
- SOFTIRQENTRY_TEXT
- *(.fixup)
- /* .gnu.warning sections are handled specially by elf32.em. */
- *(.gnu.warning)
- *(.gnu.linkonce.t*)
- }
-
- . = ALIGN(PAGE_SIZE);
- .syscall_stub : {
- __syscall_stub_start = .;
- *(.__syscall_stub*)
- __syscall_stub_end = .;
- }
-
- /*
- * These are needed even in a static link, even if they wind up being empty.
- * Newer glibc needs these __rel{,a}_iplt_{start,end} symbols.
- */
- .rel.plt : {
- *(.rel.plt)
- PROVIDE_HIDDEN(__rel_iplt_start = .);
- *(.rel.iplt)
- PROVIDE_HIDDEN(__rel_iplt_end = .);
- }
- .rela.plt : {
- *(.rela.plt)
- PROVIDE_HIDDEN(__rela_iplt_start = .);
- *(.rela.iplt)
- PROVIDE_HIDDEN(__rela_iplt_end = .);
- }
-
- #include <asm/common.lds.S>
-
- __init_begin = .;
- init.data : { INIT_DATA }
- __init_end = .;
-
- .data :
- {
- INIT_TASK_DATA(KERNEL_STACK_SIZE)
- . = ALIGN(KERNEL_STACK_SIZE);
- *(.data..init_irqstack)
- DATA_DATA
- *(.gnu.linkonce.d*)
- CONSTRUCTORS
- }
- .data1 : { *(.data1) }
- .ctors :
- {
- *(.ctors)
- }
- .dtors :
- {
- *(.dtors)
- }
-
- .got : { *(.got.plt) *(.got) }
- .dynamic : { *(.dynamic) }
- .tdata : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
- .tbss : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
- /* We want the small data sections together, so single-instruction offsets
- can access them all, and initialized data all before uninitialized, so
- we can shorten the on-disk segment size. */
- .sdata : { *(.sdata) }
- _edata = .;
- PROVIDE (edata = .);
- . = ALIGN(PAGE_SIZE);
- __bss_start = .;
- PROVIDE(_bss_start = .);
- SBSS(0)
- BSS(0)
- __bss_stop = .;
- _end = .;
- PROVIDE (end = .);
-
- STABS_DEBUG
-
- DWARF_DEBUG
-
- DISCARDS
-}
diff --git a/arch/um/kernel/vmlinux.lds.S b/arch/um/kernel/vmlinux.lds.S
index 16e49bfa2b42..aaedd66772fa 100644
--- a/arch/um/kernel/vmlinux.lds.S
+++ b/arch/um/kernel/vmlinux.lds.S
@@ -1,8 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <asm/vmlinux.lds.h>
+#include <asm/thread_info.h>
+#include <asm/page.h>
+#include <asm/thread_info.h>
+#include <asm/cache.h>
+#include <linux/export.h>
-KERNEL_STACK_SIZE = 4096 * (1 << CONFIG_KERNEL_STACK_ORDER);
+OUTPUT_FORMAT(ELF_FORMAT)
+jiffies = jiffies_64;
-#ifdef CONFIG_LD_SCRIPT_STATIC
-#include "uml.lds.S"
-#else
-#include "dyn.lds.S"
-#endif
+
+SECTIONS
+{
+ __init_begin = . ;
+ HEAD_TEXT_SECTION
+ INIT_TEXT_SECTION(PAGE_SIZE)
+ INIT_DATA_SECTION(16)
+ PERCPU_SECTION(L1_CACHE_BYTES)
+ __init_end = . ;
+
+ _stext = . ;
+ _text = . ;
+ .text : ALIGN(THREAD_SIZE)
+ {
+ __binary_start = . ;
+ TEXT_TEXT
+ SCHED_TEXT
+ LOCK_TEXT
+ CPUIDLE_TEXT
+ IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
+ }
+ _etext = . ;
+
+ .syscall_stub : ALIGN(PAGE_SIZE)
+ {
+ __syscall_stub_start = .;
+ *(.__syscall_stub*)
+ __syscall_stub_end = .;
+ }
+
+ _sdata = . ;
+ RO_DATA(PAGE_SIZE)
+ RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+ .data : ALIGN(THREAD_SIZE) { }
+
+ EXCEPTION_TABLE(16)
+
+ .uml.init_irqstack : ALIGN(THREAD_SIZE) {
+ *(.data..init_irqstack)
+ }
+
+ .uml.setup.init : ALIGN(8) {
+ __uml_setup_start = .;
+ *(.uml.setup.init)
+ __uml_setup_end = .;
+ }
+
+ .uml.help.init : ALIGN(8) {
+ __uml_help_start = .;
+ *(.uml.help.init)
+ __uml_help_end = .;
+ }
+
+ .uml.postsetup.init : ALIGN(8) {
+ __uml_postsetup_start = .;
+ *(.uml.postsetup.init)
+ __uml_postsetup_end = .;
+ }
+
+ .uml.exitcall : ALIGN(8) {
+ __uml_exitcall_begin = .;
+ *(.uml.exitcall.exit)
+ __uml_exitcall_end = .;
+ }
+ _edata = . ;
+
+ BSS_SECTION(0, 0, 0)
+ _end = . ;
+
+ STABS_DEBUG
+
+ DWARF_DEBUG
+
+ DISCARDS
+}
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index e6e2d9e5ff48..903fc8053d07 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -102,36 +102,18 @@ vmlinux_link()
strip_debug=-Wl,--strip-debug
fi
- if [ "${SRCARCH}" != "um" ]; then
- objects="--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
- --no-whole-archive \
- --start-group \
- ${KBUILD_VMLINUX_LIBS} \
- --end-group \
- ${@}"
-
- ${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} \
- ${strip_debug#-Wl,} \
- -o ${output} \
- -T ${lds} ${objects}
- else
- objects="-Wl,--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
- -Wl,--no-whole-archive \
- -Wl,--start-group \
- ${KBUILD_VMLINUX_LIBS} \
- -Wl,--end-group \
- ${@}"
-
- ${CC} ${CFLAGS_vmlinux} \
- ${strip_debug} \
- -o ${output} \
- -Wl,-T,${lds} \
- ${objects} \
- -lutil -lrt -lpthread
- rm -f linux
- fi
+ objects="--whole-archive \
+ ${KBUILD_VMLINUX_OBJS} \
+ --no-whole-archive \
+ --start-group \
+ ${KBUILD_VMLINUX_LIBS} \
+ --end-group \
+ ${@}"
+
+ ${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} \
+ ${strip_debug#-Wl,} \
+ -o ${output} \
+ -T ${lds} ${objects}
}
# generate .BTF typeinfo from DWARF debuginfo
diff --git a/tools/um/Makefile b/tools/um/Makefile
new file mode 100644
index 000000000000..a63466ef7ef5
--- /dev/null
+++ b/tools/um/Makefile
@@ -0,0 +1,72 @@
+# Do not use make's built-in rules
+# (this improves performance and avoids hard-to-debug behaviour);
+# also do not print "Entering directory..." messages from make
+.SUFFIXES:
+MAKEFLAGS += -r --no-print-directory
+
+KCONFIG?=defconfig
+
+ifneq ($(silent),1)
+ ifneq ($(V),1)
+ QUIET_AUTOCONF = @echo ' AUTOCONF '$@;
+ Q = @
+ endif
+endif
+
+PREFIX := /usr
+
+ifeq (,$(srctree))
+ srctree := $(patsubst %/,%,$(dir $(shell pwd)))
+ srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+export srctree
+
+-include ../scripts/Makefile.include
+
+# OUTPUT fixup should be *after* include ../scripts/Makefile.include
+ifneq ($(OUTPUT),)
+ OUTPUT := $(OUTPUT)/tools/um/
+else
+ OUTPUT := $(CURDIR)/
+endif
+export OUTPUT
+export objtree := $(OUTPUT)/../..
+
+
+all:
+
+export CFLAGS += -I$(OUTPUT)/include -Iinclude -Wall -g -O2 -Wextra -fPIC \
+ -Wno-unused-parameter \
+ -Wno-missing-field-initializers -fno-strict-aliasing
+
+-include Targets
+
+TARGETS := $(progs-y:%=$(OUTPUT)%)
+TARGETS += $(libs-y:%=$(OUTPUT)%)
+all: $(TARGETS)
+
+# rule to build linux.o
+$(OUTPUT)lib/linux.o:
+ $(Q)CFLAGS= $(MAKE) -C ../.. ARCH=um $(KOPT) $(KCONFIG)
+ $(Q)CFLAGS= $(MAKE) -C ../.. ARCH=um $(KOPT) install INSTALL_PATH=$(OUTPUT)
+
+$(OUTPUT)liblinux.a: $(OUTPUT)lib/linux.o $(OUTPUT)uml/liblinux-in.o
+ $(QUIET_AR)$(AR) -rc $@ $^
+
+# rule to link programs
+$(OUTPUT)%: $(OUTPUT)%-in.o $(OUTPUT)liblinux.a
+ $(QUIET_LINK)$(CC) $(LDFLAGS) $(LDFLAGS_$(notdir $*)-y) -o $@ $^ $(LDLIBS) $(LDLIBS_$(notdir $*)-y)
+
+$(OUTPUT)%-in.o: FORCE
+ $(Q)$(MAKE) -f $(srctree)/tools/build/Makefile.build dir=$(patsubst %/,%,$(dir $*)) obj=$(notdir $*)
+
+clean:
+ $(call QUIET_CLEAN, objects)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd'\
+ -delete -o -name '\.*.d' -delete
+ $(call QUIET_CLEAN, liblinux.a)$(RM) $(OUTPUT)/liblinux.a
+ $(call QUIET_CLEAN, $(TARGETS))$(RM) $(TARGETS)
+
+FORCE: ;
+.PHONY: all clean FORCE
+.IGNORE: clean
+.NOTPARALLEL : lib/linux.o
diff --git a/tools/um/Targets b/tools/um/Targets
new file mode 100644
index 000000000000..a4711f1ef422
--- /dev/null
+++ b/tools/um/Targets
@@ -0,0 +1,4 @@
+progs-y += uml/linux
+LDLIBS_linux-y := -lrt -lpthread -lutil
+LDFLAGS_linux-y := -no-pie -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc
+LDFLAGS_linux-$(UML_STATIC) += -static
diff --git a/tools/um/uml/Build b/tools/um/uml/Build
new file mode 100644
index 000000000000..e69de29bb2d1
