Revision eb35bdd7bca29a13c8ecd44e6fd747a84ce675db authored by Will Deacon on 11 September 2014, 13:38:16 UTC, committed by Will Deacon on 11 September 2014, 17:34:58 UTC
Nathan reports that we leak TLS information from the parent context
during an exec, as we don't clear the TLS registers when flushing the
thread state.
This patch updates the flushing code so that we:
(1) Unconditionally zero the tpidr_el0 register (since this is fully
context switched for native tasks and zeroed for compat tasks)
(2) Zero the tp_value state in thread_info before clearing the
tpidrr0_el0 register for compat tasks (since this is only writable
by the set_tls compat syscall and therefore not fully switched).
A missing compiler barrier is also added to the compat set_tls syscall.
Cc: <stable@vger.kernel.org>
Acked-by: Nathan Lynch <Nathan_Lynch@mentor.com>
Reported-by: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
1 parent 3d8afe3
Makefile.lib
# Backward compatibility
asflags-y += $(EXTRA_AFLAGS)
ccflags-y += $(EXTRA_CFLAGS)
cppflags-y += $(EXTRA_CPPFLAGS)
ldflags-y += $(EXTRA_LDFLAGS)
#
# flags that take effect in sub directories
export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)
export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y)
# Figure out what we need to build from the various variables
# ===========================================================================
# When an object is listed to be built compiled-in and modular,
# only build the compiled-in version
obj-m := $(filter-out $(obj-y),$(obj-m))
# Libraries are always collected in one lib file.
# Filter out objects already built-in
lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
# Handle objects in subdirs
# ---------------------------------------------------------------------------
# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o
# and add the directory to the list of dirs to descend into: $(subdir-y)
# o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
# and add the directory to the list of dirs to descend into: $(subdir-m)
# Determine modorder.
# Unfortunately, we don't have information about ordering between -y
# and -m subdirs. Just put -y's first.
modorder := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y)))
subdir-y += $(__subdir-y)
__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m)))
subdir-m += $(__subdir-m)
obj-y := $(patsubst %/, %/built-in.o, $(obj-y))
obj-m := $(filter-out %/, $(obj-m))
# Subdirectories we need to descend into
subdir-ym := $(sort $(subdir-y) $(subdir-m))
# if $(foo-objs) exists, foo.o is a composite object
multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
multi-used := $(multi-used-y) $(multi-used-m)
single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m)))
# Build list of the parts of our composite objects, our composite
# objects depend on those (obviously)
multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y)))
multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y)))
multi-objs := $(multi-objs-y) $(multi-objs-m)
# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
# tell kbuild to descend
subdir-obj-y := $(filter %/built-in.o, $(obj-y))
# $(obj-dirs) is a list of directories that contain object files
obj-dirs := $(dir $(multi-objs) $(obj-y))
# Replace multi-part objects by their individual parts, look at local dir only
real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)
real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
# Add subdir path
extra-y := $(addprefix $(obj)/,$(extra-y))
always := $(addprefix $(obj)/,$(always))
targets := $(addprefix $(obj)/,$(targets))
modorder := $(addprefix $(obj)/,$(modorder))
obj-y := $(addprefix $(obj)/,$(obj-y))
obj-m := $(addprefix $(obj)/,$(obj-m))
lib-y := $(addprefix $(obj)/,$(lib-y))
subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y))
real-objs-y := $(addprefix $(obj)/,$(real-objs-y))
real-objs-m := $(addprefix $(obj)/,$(real-objs-m))
single-used-m := $(addprefix $(obj)/,$(single-used-m))
multi-used-y := $(addprefix $(obj)/,$(multi-used-y))
multi-used-m := $(addprefix $(obj)/,$(multi-used-m))
multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y))
multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m))
subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
obj-dirs := $(addprefix $(obj)/,$(obj-dirs))
# These flags are needed for modversions and compiling, so we define them here
# already
# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will
# end up in (or would, if it gets compiled in)
# Note: Files that end up in two or more modules are compiled without the
# KBUILD_MODNAME definition. The reason is that any made-up name would
# differ in different configs.
name-fix = $(subst $(comma),_,$(subst -,_,$1))
basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))"
modname_flags = $(if $(filter 1,$(words $(modname))),\
-D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))")
orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
$(ccflags-y) $(CFLAGS_$(basetarget).o)
_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \
$(asflags-y) $(AFLAGS_$(basetarget).o)
_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))
#
# Enable gcov profiling flags for a file, directory or for all files depending
# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
# (in this order)
#
ifeq ($(CONFIG_GCOV_KERNEL),y)
_c_flags += $(if $(patsubst n%,, \
$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
$(CFLAGS_GCOV))
endif
# If building the kernel in a separate objtree expand all occurrences
# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
ifeq ($(KBUILD_SRC),)
__c_flags = $(_c_flags)
__a_flags = $(_a_flags)
__cpp_flags = $(_cpp_flags)
else
# -I$(obj) locates generated .h files
# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files
# and locates generated .h files
# FIXME: Replace both with specific CFLAGS* statements in the makefiles
__c_flags = $(call addtree,-I$(obj)) $(call flags,_c_flags)
__a_flags = $(call flags,_a_flags)
__cpp_flags = $(call flags,_cpp_flags)
endif
c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(__c_flags) $(modkern_cflags) \
-D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags)
a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(__a_flags) $(modkern_aflags)
cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(__cpp_flags)
ld_flags = $(LDFLAGS) $(ldflags-y)
dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \
-I$(srctree)/arch/$(SRCARCH)/boot/dts \
-I$(srctree)/arch/$(SRCARCH)/boot/dts/include \
-I$(srctree)/drivers/of/testcase-data \
-undef -D__DTS__
# Finds the multi-part object the current object will be linked into
modname-multi = $(sort $(foreach m,$(multi-used),\
$(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))
ifdef REGENERATE_PARSERS
# GPERF
# ---------------------------------------------------------------------------
quiet_cmd_gperf = GPERF $@
cmd_gperf = gperf -t --output-file $@ -a -C -E -g -k 1,3,$$ -p -t $<
.PRECIOUS: $(src)/%.hash.c_shipped
$(src)/%.hash.c_shipped: $(src)/%.gperf
$(call cmd,gperf)
# LEX
# ---------------------------------------------------------------------------
LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy)
quiet_cmd_flex = LEX $@
cmd_flex = flex -o$@ -L -P $(LEX_PREFIX) $<
.PRECIOUS: $(src)/%.lex.c_shipped
$(src)/%.lex.c_shipped: $(src)/%.l
$(call cmd,flex)
# YACC
# ---------------------------------------------------------------------------
YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy)
quiet_cmd_bison = YACC $@
cmd_bison = bison -o$@ -t -l -p $(YACC_PREFIX) $<
.PRECIOUS: $(src)/%.tab.c_shipped
$(src)/%.tab.c_shipped: $(src)/%.y
$(call cmd,bison)
quiet_cmd_bison_h = YACC $@
cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $<
.PRECIOUS: $(src)/%.tab.h_shipped
$(src)/%.tab.h_shipped: $(src)/%.y
$(call cmd,bison_h)
endif
# Shipped files
# ===========================================================================
quiet_cmd_shipped = SHIPPED $@
cmd_shipped = cat $< > $@
$(obj)/%: $(src)/%_shipped
$(call cmd,shipped)
# Commands useful for building a boot image
# ===========================================================================
#
# Use as following:
#
# target: source(s) FORCE
# $(if_changed,ld/objcopy/gzip)
#
# and add target to extra-y so that we know we have to
# read in the saved command line
# Linking
# ---------------------------------------------------------------------------
quiet_cmd_ld = LD $@
cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \
$(filter-out FORCE,$^) -o $@
# Objcopy
# ---------------------------------------------------------------------------
quiet_cmd_objcopy = OBJCOPY $@
cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
# Gzip
# ---------------------------------------------------------------------------
quiet_cmd_gzip = GZIP $@
cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \
(rm -f $@ ; false)
# DTC
# ---------------------------------------------------------------------------
# Generate an assembly file to wrap the output of the device tree compiler
quiet_cmd_dt_S_dtb= DTB $@
cmd_dt_S_dtb= \
( \
echo '\#include <asm-generic/vmlinux.lds.h>'; \
echo '.section .dtb.init.rodata,"a"'; \
echo '.balign STRUCT_ALIGNMENT'; \
echo '.global __dtb_$(*F)_begin'; \
echo '__dtb_$(*F)_begin:'; \
echo '.incbin "$<" '; \
echo '__dtb_$(*F)_end:'; \
echo '.global __dtb_$(*F)_end'; \
echo '.balign STRUCT_ALIGNMENT'; \
) > $@
$(obj)/%.dtb.S: $(obj)/%.dtb
$(call cmd,dt_S_dtb)
quiet_cmd_dtc = DTC $@
cmd_dtc = $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
$(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 \
-i $(dir $<) $(DTC_FLAGS) \
-d $(depfile).dtc.tmp $(dtc-tmp) ; \
cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
$(obj)/%.dtb: $(src)/%.dts FORCE
$(call if_changed_dep,dtc)
dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
# Helper targets for Installing DTBs into the boot directory
quiet_cmd_dtb_install = INSTALL $<
cmd_dtb_install = cp $< $(2)
_dtbinst_pre_:
$(Q)if [ -d $(INSTALL_DTBS_PATH).old ]; then rm -rf $(INSTALL_DTBS_PATH).old; fi
$(Q)if [ -d $(INSTALL_DTBS_PATH) ]; then mv $(INSTALL_DTBS_PATH) $(INSTALL_DTBS_PATH).old; fi
$(Q)mkdir -p $(INSTALL_DTBS_PATH)
%.dtb_dtbinst_: $(obj)/%.dtb _dtbinst_pre_
$(call cmd,dtb_install,$(INSTALL_DTBS_PATH))
# Bzip2
# ---------------------------------------------------------------------------
# Bzip2 and LZMA do not include size in file... so we have to fake that;
# append the size as a 32-bit littleendian number as gzip does.
size_append = printf $(shell \
dec_size=0; \
for F in $1; do \
fsize=$$(stat -c "%s" $$F); \
dec_size=$$(expr $$dec_size + $$fsize); \
done; \
printf "%08x\n" $$dec_size | \
sed 's/\(..\)/\1 /g' | { \
read ch0 ch1 ch2 ch3; \
for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \
printf '%s%03o' '\\' $$((0x$$ch)); \
done; \
} \
)
quiet_cmd_bzip2 = BZIP2 $@
cmd_bzip2 = (cat $(filter-out FORCE,$^) | \
bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
(rm -f $@ ; false)
# Lzma
# ---------------------------------------------------------------------------
quiet_cmd_lzma = LZMA $@
cmd_lzma = (cat $(filter-out FORCE,$^) | \
lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
(rm -f $@ ; false)
quiet_cmd_lzo = LZO $@
cmd_lzo = (cat $(filter-out FORCE,$^) | \
lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
(rm -f $@ ; false)
quiet_cmd_lz4 = LZ4 $@
cmd_lz4 = (cat $(filter-out FORCE,$^) | \
lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
(rm -f $@ ; false)
# U-Boot mkimage
# ---------------------------------------------------------------------------
MKIMAGE := $(srctree)/scripts/mkuboot.sh
# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
# the number of overrides in arch makefiles
UIMAGE_ARCH ?= $(SRCARCH)
UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
UIMAGE_OPTS-y ?=
UIMAGE_TYPE ?= kernel
UIMAGE_LOADADDR ?= arch_must_set_this
UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
UIMAGE_IN ?= $<
UIMAGE_OUT ?= $@
quiet_cmd_uimage = UIMAGE $(UIMAGE_OUT)
cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
-T $(UIMAGE_TYPE) \
-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
-n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT)
# XZ
# ---------------------------------------------------------------------------
# Use xzkern to compress the kernel image and xzmisc to compress other things.
#
# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
# of the kernel decompressor. A BCJ filter is used if it is available for
# the target architecture. xzkern also appends uncompressed size of the data
# using size_append. The .xz format has the size information available at
# the end of the file too, but it's in more complex format and it's good to
# avoid changing the part of the boot code that reads the uncompressed size.
# Note that the bytes added by size_append will make the xz tool think that
# the file is corrupt. This is expected.
#
# xzmisc doesn't use size_append, so it can be used to create normal .xz
# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
# big dictionary would increase the memory usage too much in the multi-call
# decompression mode. A BCJ filter isn't used either.
quiet_cmd_xzkern = XZKERN $@
cmd_xzkern = (cat $(filter-out FORCE,$^) | \
sh $(srctree)/scripts/xz_wrap.sh && \
$(call size_append, $(filter-out FORCE,$^))) > $@ || \
(rm -f $@ ; false)
quiet_cmd_xzmisc = XZMISC $@
cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
(rm -f $@ ; false)
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