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x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
#
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
# Building vDSO images for x86.
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
#
x86, lto: Disable LTO for the x86 VDSO The VDSO does not play well with LTO, so just disable LTO for it. Also pass a 32bit linker flag for the 32bit version. [ hpa: change braces to parens to match kernel Makefile style ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1391846481-31491-1-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-08 16:01:05 +08:00
KBUILD_CFLAGS += $(DISABLE_LTO)
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
VDSO64-$(CONFIG_X86_64) := y
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
VDSOX32-$(CONFIG_X86_X32_ABI) := y
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
VDSO32-$(CONFIG_X86_32) := y
VDSO32-$(CONFIG_COMPAT) := y
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
# files to link into the vdso
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
# files to link into kernel
x86, vdso: Patch alternatives in the 32-bit VDSO We need the alternatives mechanism for rdtsc_barrier() to work. Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-9-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-18 06:22:08 +08:00
obj-y += vma.o
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
# vDSO images to build
vdso_img-$(VDSO64-y) += 64
vdso_img-$(VDSOX32-y) += x32
vdso_img-$(VDSO32-y) += 32-int80
vdso_img-$(CONFIG_COMPAT) += 32-syscall
vdso_img-$(VDSO32-y) += 32-sysenter
obj-$(VDSO32-y) += vdso32-setup.o
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86/vdso: Hack to keep 64-bit Go programs working The Go runtime has a buggy vDSO parser that currently segfaults. This writes an empty SHT_DYNSYM entry that causes Go's runtime to malfunction by thinking that the vDSO is empty rather than malfunctioning by running off the end and segfaulting. This affects x86-64 only as far as we know, so we do not need this for the i386 and x32 vdsos. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/d10618176c4bd39b457a5e85c497295c90cab1bc.1402620737.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-13 08:53:12 +08:00
vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
$(obj)/vdso.o: $(obj)/vdso.so
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
targets += vdso.lds $(vobjs-y)
# Build the vDSO image C files and link them in.
vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o)
vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c)
vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg)
obj-y += $(vdso_img_objs)
targets += $(vdso_img_cfiles)
targets += $(vdso_img_sodbg)
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
.SECONDARY: $(vdso_img-y:%=$(obj)/vdso-image-%.c) \
$(vdso_img-y:%=$(obj)/vdso%.so)
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86: do not use $(ARCH) when not needed For x86 ARCH may say i386 or x86_64 and soon x86. Rely on CONFIG_X64_32 to select between 32/64 or just hardcode the value as appropriate. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
2007-11-13 03:14:19 +08:00
export CPPFLAGS_vdso.lds += -P -C
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86, gcc-4.6: Use gcc -m options when building vdso The vdso Makefile passes linker-style -m options not to the linker but to gcc. This happens to work with earlier gcc, but fails with gcc 4.6. Pass gcc-style -m options, instead. Note: all currently supported versions of gcc supports -m32, so there is no reason to conditionalize it any more. Reported-by: H. J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <tip-*@git.kernel.org> Cc: <stable@kernel.org>
2010-12-14 08:01:38 +08:00
VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
x86-64: Add --no-undefined to vDSO build This gives much nicer diagnostics when something goes wrong. It's supported at least as far back as binutils 2.15. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/de0b50920469ff6359c529526e7639fdd36fa83c.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13 21:24:12 +08:00
-Wl,--no-undefined \
x86, lto: Disable LTO for the x86 VDSO The VDSO does not play well with LTO, so just disable LTO for it. Also pass a 32bit linker flag for the 32bit version. [ hpa: change braces to parens to match kernel Makefile style ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1391846481-31491-1-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-08 16:01:05 +08:00
-Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 \
$(DISABLE_LTO)
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
$(obj)/vdso64.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
x86 vDSO: makefile cleanup This cleans up the arch/x86/vdso/Makefile rules for vdso.so to share more code with the vdso32-*.so rules and remove old cruft. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:44 +08:00
$(call if_changed,vdso)
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86, vdso: Use <tools/le_byteshift.h> for littleendian access There are no standard functions for littleendian data (unlike bigendian data.) Thus, use <tools/le_byteshift.h> to access littleendian data members. Those are fairly inefficient, but it doesn't matter for this purpose (and can be optimized later.) This avoids portability problems. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Tested-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/20140606140017.afb7f91142f66cb3dd13c186@linux-foundation.org
2014-06-07 05:30:37 +08:00
HOST_EXTRACFLAGS += -I$(srctree)/tools/include
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
hostprogs-y += vdso2c
quiet_cmd_vdso2c = VDSO2C $@
define cmd_vdso2c
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
$(obj)/vdso2c $< $(<:%.dbg=%) $@
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
endef
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
$(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
$(call if_changed,vdso2c)
x86: Install unstripped copy of 64bit vdso to disk This keeps an unstripped copy of the 64bit vDSO images built before they are stripped and embedded in the kernel. The unstripped copies get installed in $(MODLIB)/vdso/ by "make install" (or you can explicitly use the subtarget "make vdso_install"). These files can be useful when they contain source-level debugging information. [ tglx: arch/x86 adaptation ] Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-18 00:04:32 +08:00
x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO The vDSO isn't part of the kernel, so profiling and kernel backtraces don't really matter. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C23087b738c037342abb53f2f07b9bef89ceaeea3.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-23 21:31:29 +08:00
#
# Don't omit frame pointers for ease of userspace debugging, but do
# optimize sibling calls.
#
x86 vDSO: compile with -g, 64-bit The 64-bit vDSO's sources are compiled with -g0 for no good reason. Using -g when enabled lets their separate debug files be used at runtime via build ID matching, same as we can see 32-bit vDSO's assembly sources. Signed-off-by: Roland McGrath <roland@redhat.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-15 03:19:30 +08:00
CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO The vDSO isn't part of the kernel, so profiling and kernel backtraces don't really matter. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C23087b738c037342abb53f2f07b9bef89ceaeea3.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-23 21:31:29 +08:00
$(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
x86/vdso: Move DISABLE_BRANCH_PROFILING into the vdso makefile DISABLE_BRANCH_PROFILING turns off branch profiling (i.e. a redefinition of 'if'). Branch profiling depends on a bunch of kernel-internal symbols and generates extra output sections, none of which are useful or functional in the vDSO. It's currently turned off for vclock_gettime.c, but vgetcpu.c also triggers branch profiling, so just turn it off in the makefile. This fixes the build on some configurations: the vdso could contain undefined symbols, and the fake section table overflowed due to ftrace's added sections. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/bf1ec29e03b2bbc081f6dcaefa64db1c3a83fb21.1403642755.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-25 04:46:52 +08:00
-fno-omit-frame-pointer -foptimize-sibling-calls \
-DDISABLE_BRANCH_PROFILING
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86: include mach_apic.h in smpboot_64.c and smpboot.c After the inclusion, a lot of files needs fixing for conflicts, some of them in the headers themselves, to accomodate for both i386 and x86_64 versions. [ mingo@elte.hu: build fix ] Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-20 01:25:53 +08:00
$(vobjs): KBUILD_CFLAGS += $(CFL)
x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 23:10:01 +08:00
x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO The vDSO isn't part of the kernel, so profiling and kernel backtraces don't really matter. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C23087b738c037342abb53f2f07b9bef89ceaeea3.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-23 21:31:29 +08:00
#
# 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
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
#
# 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.
#
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
x86/vdso: Hack to keep 64-bit Go programs working The Go runtime has a buggy vDSO parser that currently segfaults. This writes an empty SHT_DYNSYM entry that causes Go's runtime to malfunction by thinking that the vDSO is empty rather than malfunctioning by running off the end and segfaulting. This affects x86-64 only as far as we know, so we do not need this for the i386 and x32 vdsos. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/d10618176c4bd39b457a5e85c497295c90cab1bc.1402620737.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-13 08:53:12 +08:00
# 64-bit objects to re-brand as x32
vobjs64-for-x32 := $(filter-out $(vobjs-nox32),$(vobjs-y))
# x32-rebranded versions
vobjx32s-y := $(vobjs64-for-x32:.o=-x32.o)
# same thing, but in the output directory
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
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)
x86, vdso: Reimplement vdso.so preparation in build-time C Currently, vdso.so files are prepared and analyzed by a combination of objcopy, nm, some linker script tricks, and some simple ELF parsers in the kernel. Replace all of that with plain C code that runs at build time. All five vdso images now generate .c files that are compiled and linked in to the kernel image. This should cause only one userspace-visible change: the loaded vDSO images are stripped more heavily than they used to be. Everything outside the loadable segment is dropped. In particular, this causes the section table and section name strings to be missing. This should be fine: real dynamic loaders don't load or inspect these tables anyway. The result is roughly equivalent to eu-strip's --strip-sections option. The purpose of this change is to enable the vvar and hpet mappings to be moved to the page following the vDSO load segment. Currently, it is possible for the section table to extend into the page after the load segment, so, if we map it, it risks overlapping the vvar or hpet page. This happens whenever the load segment is just under a multiple of PAGE_SIZE. The only real subtlety here is that the old code had a C file with inline assembler that did 'call VDSO32_vsyscall' and a linker script that defined 'VDSO32_vsyscall = __kernel_vsyscall'. This most likely worked by accident: the linker script entry defines a symbol associated with an address as opposed to an alias for the real dynamic symbol __kernel_vsyscall. That caused ld to relocate the reference at link time instead of leaving an interposable dynamic relocation. Since the VDSO32_vsyscall hack is no longer needed, I now use 'call __kernel_vsyscall', and I added -Bsymbolic to make it work. vdso2c will generate an error and abort the build if the resulting image contains any dynamic relocations, so we won't silently generate bad vdso images. (Dynamic relocations are a problem because nothing will even attempt to relocate the vdso.) Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/2c4fcf45524162a34d87fdda1eb046b2a5cecee7.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-06 03:19:34 +08:00
targets += vdsox32.lds $(vobjx32s-y)
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg
$(call if_changed,objcopy)
x32: Add x32 VDSO support Add support for the x32 VDSO. The x32 VDSO takes advantage of the similarity between the x86-64 and the x32 ABIs to contain the same content, only the container is different, as the x32 VDSO obviously is an x32 shared object. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 03:38:06 +08:00
$(obj)/vdsox32.so.dbg: $(src)/vdsox32.lds $(vobjx32s) FORCE
$(call if_changed,vdso)
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
#
# Build multiple 32-bit vDSO images to choose from at boot time.
#
x86_64: further cleanup of 32-bit compat syscall mechanisms AMD only supports "syscall" from 32-bit compat usermode. Intel and Centaur(?) only support "sysenter" from 32-bit compat usermode. Set the X86 feature bits accordingly, and set up the vdso in accordance with those bits. On the offchance we run on in a 64-bit environment which supports neither syscall nor sysenter from 32-bit mode, then fall back to the int $0x80 vdso. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-07-12 17:22:00 +08:00
vdso32.so-$(VDSO32-y) += int80
x86 vDSO: ia32 vdso32-syscall build This puts the syscall version of the 32-bit vDSO in arch/x86/vdso/vdso32/ for 64-bit IA32 support. This is not used yet, but it paves the way for consolidating the 32-bit vDSO source and build logic all in one place. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:43 +08:00
vdso32.so-$(CONFIG_COMPAT) += syscall
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
vdso32.so-$(VDSO32-y) += sysenter
x86: vdso_install fix The makefile magic for installing the 32-bit vdso images on disk had a little error. A single-line change would fix that bug, but this does a little more to reduce the error-prone duplication of this bit of makefile variable magic. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12 06:38:51 +08:00
vdso32-images = $(vdso32.so-y:%=vdso32-%.so)
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
x86, lto: Disable LTO for the x86 VDSO The VDSO does not play well with LTO, so just disable LTO for it. Also pass a 32bit linker flag for the 32bit version. [ hpa: change braces to parens to match kernel Makefile style ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1391846481-31491-1-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-08 16:01:05 +08:00
VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
# 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
x86, vdso, build: Don't rebuild 32-bit vdsos on every make vdso32/vclock_gettime.o was confusing kbuild. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/d741449340642213744dd659471a35bb970a0c4c.1395789923.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-26 07:25:53 +08:00
targets += vdso32/note.o vdso32/vclock_gettime.o $(vdso32.so-y:%=vdso32/%.o)
x86, vdso: Get rid of the fake section mechanism Now that we can tolerate extra things dangling off the end of the vdso image, we can strip the vdso the old fashioned way rather than using an overcomplicated custom stripping algorithm. This is a partial reversion of: 6f121e5 x86, vdso: Reimplement vdso.so preparation in build-time C Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/50e01ed6dcc0575d20afd782f9fe98d5ee3e2d8a.1405040914.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-11 09:13:16 +08:00
targets += vdso32/vclock_gettime.o
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
x86: vdso_install fix The makefile magic for installing the 32-bit vdso images on disk had a little error. A single-line change would fix that bug, but this does a little more to reduce the error-prone duplication of this bit of makefile variable magic. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12 06:38:51 +08:00
$(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%)
x86 vDSO: i386 vdso32 This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/ to replace the old one from arch/x86/kernel/. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
x86: vdso_install fix The makefile magic for installing the 32-bit vdso images on disk had a little error. A single-line change would fix that bug, but this does a little more to reduce the error-prone duplication of this bit of makefile variable magic. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12 06:38:51 +08:00
$(vdso32-images:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
$(vdso32-images:%=$(obj)/%.dbg): asflags-$(CONFIG_X86_64) += -m32
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
x86, vdso: Add 32 bit VDSO time support for 32 bit kernel This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit kernel. Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-10-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-18 06:22:09 +08:00
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
x86, vdso32: Disable stack protector, adjust optimizations For the 32-bit VDSO, match the 64-bit VDSO in: 1. Disable the stack protector. 2. Use -fno-omit-frame-pointer for user space debugging sanity. 3. Use -foptimize-sibling-calls like the 64-bit VDSO does. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-13-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-18 06:22:12 +08:00
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
x86/vdso: Move DISABLE_BRANCH_PROFILING into the vdso makefile DISABLE_BRANCH_PROFILING turns off branch profiling (i.e. a redefinition of 'if'). Branch profiling depends on a bunch of kernel-internal symbols and generates extra output sections, none of which are useful or functional in the vDSO. It's currently turned off for vclock_gettime.c, but vgetcpu.c also triggers branch profiling, so just turn it off in the makefile. This fixes the build on some configurations: the vdso could contain undefined symbols, and the fake section table overflowed due to ftrace's added sections. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/bf1ec29e03b2bbc081f6dcaefa64db1c3a83fb21.1403642755.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-25 04:46:52 +08:00
KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
x86, vdso: Add 32 bit VDSO time support for 32 bit kernel This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit kernel. Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-10-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-18 06:22:09 +08:00
$(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
x86: vdso_install fix The makefile magic for installing the 32-bit vdso images on disk had a little error. A single-line change would fix that bug, but this does a little more to reduce the error-prone duplication of this bit of makefile variable magic. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12 06:38:51 +08:00
$(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \
$(obj)/vdso32/vdso32.lds \
x86, vdso: Add 32 bit VDSO time support for 32 bit kernel This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit kernel. Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-10-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-18 06:22:09 +08:00
$(obj)/vdso32/vclock_gettime.o \
x86: vdso_install fix The makefile magic for installing the 32-bit vdso images on disk had a little error. A single-line change would fix that bug, but this does a little more to reduce the error-prone duplication of this bit of makefile variable magic. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-12 06:38:51 +08:00
$(obj)/vdso32/note.o \
$(obj)/vdso32/%.o
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
$(call if_changed,vdso)
#
# 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,$(^F))) \
x86, vdso: Error out if the vdso contains external references The vdso is a piece of userspace code which is supposed to be fully self-contained. Any external (undefined) reference is an error, and should be caught at compile time. This was giving us trouble when compiling with -Os on gcc 4.5.0, for example (failed inline). The need to do a buildtime check was pointed out by Andi Kleen. Reported-by: Andi Kleen <andi@firstfloor.org> LKML-Reference: <tip-*@vger.kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-06-19 05:36:26 +08:00
-Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
x86, lto: Disable LTO for the x86 VDSO The VDSO does not play well with LTO, so just disable LTO for it. Also pass a 32bit linker flag for the 32bit version. [ hpa: change braces to parens to match kernel Makefile style ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1391846481-31491-1-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-08 16:01:05 +08:00
VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \
x86/vdso: Create .build-id links for unstripped vdso files With this change, doing 'make vdso_install' and telling gdb: set debug-file-directory /lib/modules/KVER/vdso will enable vdso debugging with symbols. This is useful for testing, but kernel RPM builds will probably want to manually delete these symlinks or otherwise do something sensible when they strip the vdso/*.so files. If ld does not support --build-id, then the symlinks will not be created. Note that kernel packagers that use vdso_install may need to adjust their packaging scripts to accomdate this change. For example, Fedora's scripts create build-id symlinks themselves in a different location, so the spec should probably be updated to remove the symlinks created by make vdso_install. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a424b189ce3ced85fe1e82d032a20e765e0fe0d3.1403291930.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-21 03:20:44 +08:00
$(call cc-ldoption, -Wl$(comma)--build-id) -Wl,-Bsymbolic $(LTO_CFLAGS)
gcov: enable GCOV_PROFILE_ALL for x86_64 Enable gcov profiling of the entire kernel on x86_64. Required changes include disabling profiling for: * arch/kernel/acpi/realmode and arch/kernel/boot/compressed: not linked to main kernel * arch/vdso, arch/kernel/vsyscall_64 and arch/kernel/hpet: profiling causes segfaults during boot (incompatible context) Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 07:28:09 +08:00
GCOV_PROFILE := n
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
#
x86/vdso: Create .build-id links for unstripped vdso files With this change, doing 'make vdso_install' and telling gdb: set debug-file-directory /lib/modules/KVER/vdso will enable vdso debugging with symbols. This is useful for testing, but kernel RPM builds will probably want to manually delete these symlinks or otherwise do something sensible when they strip the vdso/*.so files. If ld does not support --build-id, then the symlinks will not be created. Note that kernel packagers that use vdso_install may need to adjust their packaging scripts to accomdate this change. For example, Fedora's scripts create build-id symlinks themselves in a different location, so the spec should probably be updated to remove the symlinks created by make vdso_install. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a424b189ce3ced85fe1e82d032a20e765e0fe0d3.1403291930.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-21 03:20:44 +08:00
# Install the unstripped copies of vdso*.so. If our toolchain supports
# build-id, install .build-id links as well.
x86 vDSO: vdso32 build This builds the 32-bit vDSO images in the arch/x86/vdso subdirectory. Nothing uses the images yet, but this paves the way for consolidating the vDSO build logic all in one place. The new images use a linker script sharing the layout parts from vdso-layout.lds.S with the 64-bit vDSO. A new vdso32-syms.lds is generated in the style of vdso-syms.lds. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:30:42 +08:00
#
x86/vdso: Fix vdso_install "make vdso_install" installs unstripped versions of the vdso objects for the benefit of the debugger. This was broken by checkin: 6f121e548f83 x86, vdso: Reimplement vdso.so preparation in build-time C The filenames are different now, so update the Makefile to cope. This still installs the 64-bit vdso as vdso64.so. We believe this will be okay, as the only known user is a patched gdb which is known to use build-ids, but if it turns out to be a problem we may have to add a link. Inspired by a patch from Sam Ravnborg. Acked-by: Sam Ravnborg <sam@ravnborg.org> Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/b10299edd8ba98d17e07dafcd895b8ecf4d99eff.1402586707.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-12 23:28:10 +08:00
quiet_cmd_vdso_install = INSTALL $(@:install_%=%)
x86/vdso: Create .build-id links for unstripped vdso files With this change, doing 'make vdso_install' and telling gdb: set debug-file-directory /lib/modules/KVER/vdso will enable vdso debugging with symbols. This is useful for testing, but kernel RPM builds will probably want to manually delete these symlinks or otherwise do something sensible when they strip the vdso/*.so files. If ld does not support --build-id, then the symlinks will not be created. Note that kernel packagers that use vdso_install may need to adjust their packaging scripts to accomdate this change. For example, Fedora's scripts create build-id symlinks themselves in a different location, so the spec should probably be updated to remove the symlinks created by make vdso_install. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/a424b189ce3ced85fe1e82d032a20e765e0fe0d3.1403291930.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-21 03:20:44 +08:00
define cmd_vdso_install
cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \
if readelf -n $< |grep -q 'Build ID'; then \
buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
first=`echo $$buildid | cut -b-2`; \
last=`echo $$buildid | cut -b3-`; \
mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
fi
endef
x86/vdso: Fix vdso_install "make vdso_install" installs unstripped versions of the vdso objects for the benefit of the debugger. This was broken by checkin: 6f121e548f83 x86, vdso: Reimplement vdso.so preparation in build-time C The filenames are different now, so update the Makefile to cope. This still installs the 64-bit vdso as vdso64.so. We believe this will be okay, as the only known user is a patched gdb which is known to use build-ids, but if it turns out to be a problem we may have to add a link. Inspired by a patch from Sam Ravnborg. Acked-by: Sam Ravnborg <sam@ravnborg.org> Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/b10299edd8ba98d17e07dafcd895b8ecf4d99eff.1402586707.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-12 23:28:10 +08:00
vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%)
$(MODLIB)/vdso: FORCE
x86: Install unstripped copy of 64bit vdso to disk This keeps an unstripped copy of the 64bit vDSO images built before they are stripped and embedded in the kernel. The unstripped copies get installed in $(MODLIB)/vdso/ by "make install" (or you can explicitly use the subtarget "make vdso_install"). These files can be useful when they contain source-level debugging information. [ tglx: arch/x86 adaptation ] Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-18 00:04:32 +08:00
@mkdir -p $(MODLIB)/vdso
x86/vdso: Fix vdso_install "make vdso_install" installs unstripped versions of the vdso objects for the benefit of the debugger. This was broken by checkin: 6f121e548f83 x86, vdso: Reimplement vdso.so preparation in build-time C The filenames are different now, so update the Makefile to cope. This still installs the 64-bit vdso as vdso64.so. We believe this will be okay, as the only known user is a patched gdb which is known to use build-ids, but if it turns out to be a problem we may have to add a link. Inspired by a patch from Sam Ravnborg. Acked-by: Sam Ravnborg <sam@ravnborg.org> Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/b10299edd8ba98d17e07dafcd895b8ecf4d99eff.1402586707.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-12 23:28:10 +08:00
$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE
x86: Install unstripped copy of 64bit vdso to disk This keeps an unstripped copy of the 64bit vDSO images built before they are stripped and embedded in the kernel. The unstripped copies get installed in $(MODLIB)/vdso/ by "make install" (or you can explicitly use the subtarget "make vdso_install"). These files can be useful when they contain source-level debugging information. [ tglx: arch/x86 adaptation ] Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-18 00:04:32 +08:00
$(call cmd,vdso_install)
x86/vdso: Fix vdso_install "make vdso_install" installs unstripped versions of the vdso objects for the benefit of the debugger. This was broken by checkin: 6f121e548f83 x86, vdso: Reimplement vdso.so preparation in build-time C The filenames are different now, so update the Makefile to cope. This still installs the 64-bit vdso as vdso64.so. We believe this will be okay, as the only known user is a patched gdb which is known to use build-ids, but if it turns out to be a problem we may have to add a link. Inspired by a patch from Sam Ravnborg. Acked-by: Sam Ravnborg <sam@ravnborg.org> Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Tested-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/b10299edd8ba98d17e07dafcd895b8ecf4d99eff.1402586707.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-12 23:28:10 +08:00
PHONY += vdso_install $(vdso_img_insttargets)
vdso_install: $(vdso_img_insttargets) FORCE
x86: teach vdso to clean A few files remained after 'make clean' in arch/x86/vdso/. Teach vdso to clean up those files in a bit brutal fashion. The filenames are just hardcoded in the Makefile. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Roland McGrath <roland@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 20:32:27 +08:00
clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80*