diff options
Diffstat (limited to 'arch/mips/vdso')
| -rw-r--r-- | arch/mips/vdso/.gitignore | 1 | ||||
| -rw-r--r-- | arch/mips/vdso/Kconfig | 6 | ||||
| -rw-r--r-- | arch/mips/vdso/Makefile | 59 | ||||
| -rw-r--r-- | arch/mips/vdso/genvdso.c | 19 | ||||
| -rw-r--r-- | arch/mips/vdso/vdso.lds.S | 4 | ||||
| -rw-r--r-- | arch/mips/vdso/vgettimeofday.c | 21 |
6 files changed, 74 insertions, 36 deletions
diff --git a/arch/mips/vdso/.gitignore b/arch/mips/vdso/.gitignore index 5286a7d73d79..1f43f6dd8142 100644 --- a/arch/mips/vdso/.gitignore +++ b/arch/mips/vdso/.gitignore @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only *.so* vdso-*image.c genvdso diff --git a/arch/mips/vdso/Kconfig b/arch/mips/vdso/Kconfig new file mode 100644 index 000000000000..70140248da72 --- /dev/null +++ b/arch/mips/vdso/Kconfig @@ -0,0 +1,6 @@ +# GCC (at least up to version 9.2) appears to emit function calls that make use +# of the GOT when targeting microMIPS, which we can't use in the VDSO due to +# the lack of relocations. As such, we disable the VDSO for microMIPS builds. + +config MIPS_DISABLE_VDSO + def_bool CPU_MICROMIPS diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile index e05938997e69..eb56581f6d73 100644 --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -1,9 +1,10 @@ # SPDX-License-Identifier: GPL-2.0 # Objects to go into the VDSO. -# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before -# the inclusion of generic Makefile. -ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT +# Sanitizer runtimes are unavailable and cannot be linked here. + KCSAN_SANITIZE := n + +# Include the generic Makefile to check the built vdso. include $(srctree)/lib/vdso/Makefile obj-vdso-y := elf.o vgettimeofday.o sigreturn.o @@ -16,10 +17,11 @@ ccflags-vdso := \ $(filter -march=%,$(KBUILD_CFLAGS)) \ $(filter -m%-float,$(KBUILD_CFLAGS)) \ $(filter -mno-loongson-%,$(KBUILD_CFLAGS)) \ + $(CLANG_FLAGS) \ -D__VDSO__ -ifdef CONFIG_CC_IS_CLANG -ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS)) +ifndef CONFIG_64BIT +ccflags-vdso += -DBUILD_VDSO32 endif # @@ -29,9 +31,9 @@ endif cflags-vdso := $(ccflags-vdso) \ $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ -O3 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \ + -mrelax-pic-calls $(call cc-option, -mexplicit-relocs) \ -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ - $(call cc-option, -fno-asynchronous-unwind-tables) \ - $(call cc-option, -fno-stack-protector) + $(call cc-option, -fno-asynchronous-unwind-tables) aflags-vdso := $(ccflags-vdso) \ -D__ASSEMBLY__ -Wa,-gdwarf-2 @@ -45,48 +47,35 @@ CFLAGS_vgettimeofday-o32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -in CFLAGS_vgettimeofday-n32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y) endif -CFLAGS_REMOVE_vgettimeofday.o = -pg +CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -# -# For the pre-R6 code in arch/mips/vdso/vdso.h for locating -# the base address of VDSO, the linker will emit a R_MIPS_PC32 -# relocation in binutils > 2.25 but it will fail with older versions -# because that relocation is not supported for that symbol. As a result -# of which we are forced to disable the VDSO symbols when building -# with < 2.25 binutils on pre-R6 kernels. For more references on why we -# can't use other methods to get the base address of VDSO please refer to -# the comments on that file. -# -ifndef CONFIG_CPU_MIPSR6 - ifeq ($(call ld-ifversion, -lt, 225000000, y),y) - $(warning MIPS VDSO requires binutils >= 2.25) - obj-vdso-y := $(filter-out vgettimeofday.o, $(obj-vdso-y)) - ccflags-vdso += -DDISABLE_MIPS_VDSO - endif +ifdef CONFIG_MIPS_DISABLE_VDSO + obj-vdso-y := $(filter-out vgettimeofday.o, $(obj-vdso-y)) endif # VDSO linker flags. -VDSO_LDFLAGS := \ - -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1 \ - $(addprefix -Wl$(comma),$(filter -E%,$(KBUILD_CFLAGS))) \ - -nostdlib -shared -Wl,--hash-style=sysv -Wl,--build-id +ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ + $(filter -E%,$(KBUILD_CFLAGS)) -shared \ + -G 0 --eh-frame-hdr --hash-style=sysv --build-id=sha1 -T -CFLAGS_REMOVE_vdso.o = -pg +CFLAGS_REMOVE_vdso.o = $(CC_FLAGS_FTRACE) GCOV_PROFILE := n UBSAN_SANITIZE := n KCOV_INSTRUMENT := n +# Check that we don't have PIC 'jalr t9' calls left +quiet_cmd_vdso_mips_check = VDSOCHK $@ + cmd_vdso_mips_check = if $(OBJDUMP) --disassemble $@ | grep -E -h "jalr.*t9" > /dev/null; \ + then (echo >&2 "$@: PIC 'jalr t9' calls are not supported"; \ + rm -f $@; /bin/false); fi + # # Shared build commands. # quiet_cmd_vdsold_and_vdso_check = LD $@ - cmd_vdsold_and_vdso_check = $(cmd_vdsold); $(cmd_vdso_check) - -quiet_cmd_vdsold = VDSO $@ - cmd_vdsold = $(CC) $(c_flags) $(VDSO_LDFLAGS) \ - -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@ + cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check); $(cmd_vdso_mips_check) quiet_cmd_vdsoas_o_S = AS $@ cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $< @@ -96,7 +85,7 @@ $(obj)/%.so.raw: OBJCOPYFLAGS := -S $(obj)/%.so.raw: $(obj)/%.so.dbg.raw FORCE $(call if_changed,objcopy) -hostprogs-y := genvdso +hostprogs := genvdso quiet_cmd_genvdso = GENVDSO $@ define cmd_genvdso diff --git a/arch/mips/vdso/genvdso.c b/arch/mips/vdso/genvdso.c index b66b6b1c4aeb..09e30eb4be86 100644 --- a/arch/mips/vdso/genvdso.c +++ b/arch/mips/vdso/genvdso.c @@ -122,6 +122,7 @@ static void *map_vdso(const char *path, size_t *_size) if (fstat(fd, &stat) != 0) { fprintf(stderr, "%s: Failed to stat '%s': %s\n", program_name, path, strerror(errno)); + close(fd); return NULL; } @@ -130,6 +131,7 @@ static void *map_vdso(const char *path, size_t *_size) if (addr == MAP_FAILED) { fprintf(stderr, "%s: Failed to map '%s': %s\n", program_name, path, strerror(errno)); + close(fd); return NULL; } @@ -139,6 +141,7 @@ static void *map_vdso(const char *path, size_t *_size) if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0) { fprintf(stderr, "%s: '%s' is not an ELF file\n", program_name, path); + close(fd); return NULL; } @@ -150,6 +153,7 @@ static void *map_vdso(const char *path, size_t *_size) default: fprintf(stderr, "%s: '%s' has invalid ELF class\n", program_name, path); + close(fd); return NULL; } @@ -161,6 +165,7 @@ static void *map_vdso(const char *path, size_t *_size) default: fprintf(stderr, "%s: '%s' has invalid ELF data order\n", program_name, path); + close(fd); return NULL; } @@ -168,15 +173,18 @@ static void *map_vdso(const char *path, size_t *_size) fprintf(stderr, "%s: '%s' has invalid ELF machine (expected EM_MIPS)\n", program_name, path); + close(fd); return NULL; } else if (swap_uint16(ehdr->e_type) != ET_DYN) { fprintf(stderr, "%s: '%s' has invalid ELF type (expected ET_DYN)\n", program_name, path); + close(fd); return NULL; } *_size = stat.st_size; + close(fd); return addr; } @@ -251,6 +259,14 @@ int main(int argc, char **argv) fprintf(out_file, "#include <linux/linkage.h>\n"); fprintf(out_file, "#include <linux/mm.h>\n"); fprintf(out_file, "#include <asm/vdso.h>\n"); + fprintf(out_file, "static int vdso_mremap(\n"); + fprintf(out_file, " const struct vm_special_mapping *sm,\n"); + fprintf(out_file, " struct vm_area_struct *new_vma)\n"); + fprintf(out_file, "{\n"); + fprintf(out_file, " current->mm->context.vdso =\n"); + fprintf(out_file, " (void *)(new_vma->vm_start);\n"); + fprintf(out_file, " return 0;\n"); + fprintf(out_file, "}\n"); /* Write out the stripped VDSO data. */ fprintf(out_file, @@ -275,15 +291,18 @@ int main(int argc, char **argv) fprintf(out_file, "\t.mapping = {\n"); fprintf(out_file, "\t\t.name = \"[vdso]\",\n"); fprintf(out_file, "\t\t.pages = vdso_pages,\n"); + fprintf(out_file, "\t\t.mremap = vdso_mremap,\n"); fprintf(out_file, "\t},\n"); /* Calculate and write symbol offsets to <output file> */ if (!get_symbols(dbg_vdso_path, dbg_vdso)) { unlink(out_path); + fclose(out_file); return EXIT_FAILURE; } fprintf(out_file, "};\n"); + fclose(out_file); return EXIT_SUCCESS; } diff --git a/arch/mips/vdso/vdso.lds.S b/arch/mips/vdso/vdso.lds.S index da4627430aba..836465e3bcb8 100644 --- a/arch/mips/vdso/vdso.lds.S +++ b/arch/mips/vdso/vdso.lds.S @@ -91,10 +91,12 @@ PHDRS VERSION { LINUX_2.6 { -#ifndef DISABLE_MIPS_VDSO +#ifndef CONFIG_MIPS_DISABLE_VDSO global: __vdso_clock_gettime; +#ifdef CONFIG_MIPS_CLOCK_VSYSCALL __vdso_gettimeofday; +#endif __vdso_clock_getres; #if _MIPS_SIM != _MIPS_SIM_ABI64 __vdso_clock_gettime64; diff --git a/arch/mips/vdso/vgettimeofday.c b/arch/mips/vdso/vgettimeofday.c index 6ebdc37c89fc..604afea3f336 100644 --- a/arch/mips/vdso/vgettimeofday.c +++ b/arch/mips/vdso/vgettimeofday.c @@ -9,6 +9,7 @@ */ #include <linux/time.h> #include <linux/types.h> +#include <vdso/gettime.h> #if _MIPS_SIM != _MIPS_SIM_ABI64 int __vdso_clock_gettime(clockid_t clock, @@ -17,12 +18,22 @@ int __vdso_clock_gettime(clockid_t clock, return __cvdso_clock_gettime32(clock, ts); } +#ifdef CONFIG_MIPS_CLOCK_VSYSCALL + +/* + * This is behind the ifdef so that we don't provide the symbol when there's no + * possibility of there being a usable clocksource, because there's nothing we + * can do without it. When libc fails the symbol lookup it should fall back on + * the standard syscall path. + */ int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) { return __cvdso_gettimeofday(tv, tz); } +#endif /* CONFIG_MIPS_CLOCK_VSYSCALL */ + int __vdso_clock_getres(clockid_t clock_id, struct old_timespec32 *res) { @@ -43,12 +54,22 @@ int __vdso_clock_gettime(clockid_t clock, return __cvdso_clock_gettime(clock, ts); } +#ifdef CONFIG_MIPS_CLOCK_VSYSCALL + +/* + * This is behind the ifdef so that we don't provide the symbol when there's no + * possibility of there being a usable clocksource, because there's nothing we + * can do without it. When libc fails the symbol lookup it should fall back on + * the standard syscall path. + */ int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) { return __cvdso_gettimeofday(tv, tz); } +#endif /* CONFIG_MIPS_CLOCK_VSYSCALL */ + int __vdso_clock_getres(clockid_t clock_id, struct __kernel_timespec *res) { |