switch-linux/arch/x86/kernel
Andy Lutomirski 6f121e548f 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>
2014-05-05 13:18:51 -07:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux into pm-cpuidle 2014-04-08 13:25:25 +02:00
apic genirq: x86: Ensure that dynamic irq allocation does not conflict 2014-04-28 12:20:00 +02:00
cpu x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.c 2014-05-05 13:18:47 -07:00
kprobes kprobes/x86: Fix page-fault handling logic 2014-04-17 10:57:02 +02:00
.gitignore
alternative.c lockdep, x86/alternatives: Drop ancient lockdep fixup message 2013-09-28 10:09:41 +02:00
amd_gart_64.c
amd_nb.c A bunch of EDAC updates all over the place: 2014-04-01 13:54:00 -07:00
apb_timer.c intel_mid: Renamed *mrst* to *intel_mid* 2013-10-17 16:40:47 -07:00
aperture_64.c Revert "[PATCH] Insert GART region into resource map" 2014-03-18 14:26:12 -06:00
apm_32.c x86, asmlinkage, apm: Make APM data structure used from assembler visible 2013-08-06 14:20:20 -07:00
asm-offsets.c sched, x86: Provide a per-cpu preempt_count implementation 2013-09-25 14:07:57 +02:00
asm-offsets_32.c x86: Get rid of ->hard_math and all the FPU asm fu 2013-06-06 14:32:04 -07:00
asm-offsets_64.c x86, gdt, hibernate: Store/load GDT for hibernate path. 2013-05-02 11:27:35 -07:00
audit_64.c
bootflag.c
check.c x86/mm: memblock: switch to use NUMA_NO_NODE 2014-01-21 16:19:47 -08:00
cpuid.c x86, cpuid: Fix CPU hotplug callback registration 2014-03-20 13:43:42 +01:00
crash.c x86, crash: Unify ifdef 2014-03-13 15:32:44 -07:00
crash_dump_32.c
crash_dump_64.c
devicetree.c Merge remote-tracking branch 'grant/devicetree/next' into for-next 2013-11-07 10:34:46 -06:00
doublefault.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
dumpstack.c x86/dumpstack: Fix printk_address for direct addresses 2013-11-12 21:06:06 +01:00
dumpstack_32.c Merge branch 'x86-threadinfo-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-01 10:17:18 -07:00
dumpstack_64.c x86: Fix dumpstack_64 irq stack handling 2014-04-02 11:46:50 -07:00
e820.c x86/mm: memblock: switch to use NUMA_NO_NODE 2014-01-21 16:19:47 -08:00
early-quirks.c x86/gpu: Fix sign extension issue in Intel graphics stolen memory quirks 2014-04-14 08:50:56 +02:00
early_printk.c Merge branch 'x86-intel-mid-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-12 11:12:22 +09:00
entry_32.S ftrace/x86: Load ftrace_ops in parameter not the variable holding it 2014-01-09 13:24:29 -08:00
entry_64.S ftrace/x86: Load ftrace_ops in parameter not the variable holding it 2014-01-09 13:24:29 -08:00
ftrace.c ftrace/x86: BUG when ftrace recovery fails 2014-03-07 10:06:16 -05:00
head.c x86: Make sure we can boot in the case the BDA contains pure garbage 2013-02-27 13:38:57 -08:00
head32.c intel_mid: Renamed *mrst* to *intel_mid* 2013-10-17 16:40:47 -07:00
head64.c x86, trace: Register exception handler to trace IDT 2013-11-08 14:15:45 -08:00
head_32.S x86: fix compile error due to X86_TRAP_NMI use in asm files 2014-03-07 18:58:40 -08:00
head_64.S x86: fix compile error due to X86_TRAP_NMI use in asm files 2014-03-07 18:58:40 -08:00
hpet.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
hw_breakpoint.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
i386_ksyms_32.c sched, x86: Optimize the preempt_schedule() call 2013-09-25 14:23:07 +02:00
i387.c x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPU 2014-03-11 12:32:52 -07:00
i8237.c
i8253.c
i8259.c x86/irq: Correct comment about i8259 initialization 2013-09-04 07:46:04 +02:00
io_delay.c
ioport.c x86: get rid of pt_regs argument of iopl(2) 2013-02-03 18:16:24 -05:00
iosf_mbi.c arch: x86: New MailBox support driver for Intel SOC's 2014-01-08 14:36:29 -08:00
irq.c x86/platform/hyperv: Handle VMBUS driver being a module 2014-04-02 09:49:47 +02:00
irq_32.c x86, threadinfo: Redo "x86: Use inline assembler to get sp" 2014-03-10 17:32:01 -07:00
irq_64.c irq: Consolidate do_softirq() arch overriden implementations 2013-10-01 12:53:25 +02:00
irq_work.c x86, asmlinkage: Make all interrupt handlers asmlinkage / __visible 2013-08-06 14:18:23 -07:00
irqinit.c x86/irq: Fix do_IRQ() interrupt warning for cpu hotplug retriggered irqs 2014-01-12 13:13:02 +01:00
jump_label.c x86/jump_label: expect default_nop if static_key gets enabled on boot-up 2013-10-19 19:45:35 -04:00
kdebugfs.c
kgdb.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
ksysfs.c x86: ksysfs.c build fix 2014-01-03 14:37:13 +00:00
kvm.c kvm: remove redundant registration of BSP's hv_clock area 2014-02-22 15:53:32 +01:00
kvmclock.c kvm: remove redundant registration of BSP's hv_clock area 2014-02-22 15:53:32 +01:00
ldt.c x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels 2014-04-11 10:10:09 -07:00
machine_kexec_32.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
machine_kexec_64.c x86, kaslr: export offset in VMCOREINFO ELF notes 2014-02-25 16:57:47 -08:00
Makefile x86, vdso: Make vsyscall_gtod_data handling x86 generic 2014-03-18 12:51:52 -07:00
mmconf-fam10h_64.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
module.c x86, kaslr: fix module lock ordering problem 2014-03-24 10:18:26 -07:00
mpparse.c
msr.c x86, msr: Fix CPU hotplug callback registration 2014-03-20 13:43:42 +01:00
nmi.c x86/nmi: Push duration printk() to irq context 2014-02-09 13:17:22 +01:00
nmi_selftest.c
paravirt-spinlocks.c x86, ticketlock: Add slowpath logic 2013-08-09 07:54:00 -07:00
paravirt.c x86, paravirt: Remove duplicate definition for DEF_NATIVE 2013-09-04 09:46:43 -07:00
paravirt_patch_32.c
paravirt_patch_64.c
pci-calgary_64.c x86, calgary: Use 8M TCE table size by default 2014-04-10 19:51:32 -07:00
pci-dma.c x86: dma-mapping: fix GFP_ATOMIC macro usage 2014-02-11 09:40:15 +01:00
pci-iommu_table.c
pci-nommu.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
pci-swiotlb.c
pcspeaker.c
perf_regs.c
preempt.S sched, x86: Optimize the preempt_schedule() call 2013-09-25 14:23:07 +02:00
probe_roms.c
process.c sched/idle, x86: Remove redundant cpuidle_idle_call() 2014-02-11 09:58:28 +01:00
process_32.c x86: Keep thread_info on thread stack in x86_32 2014-03-06 16:56:55 -08:00
process_64.c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-14 16:55:56 +09:00
ptrace.c x86: Keep thread_info on thread stack in x86_32 2014-03-06 16:56:55 -08:00
pvclock.c hung_task: add method to reset detector 2013-11-06 09:49:02 +02:00
quirks.c x86/amd/numa: Fix northbridge quirk to assign correct NUMA node 2014-03-14 11:05:36 +01:00
reboot.c x86: Remove the PCI reboot method from the default chain 2014-04-16 08:56:09 +02:00
reboot_fixups_32.c
relocate_kernel_32.S x86, asm, cleanup: Replace open-coded control register values with symbolic 2013-06-25 16:26:06 -07:00
relocate_kernel_64.S x86, reloc: Use xorl instead of xorq in relocate_kernel_64.S 2013-06-20 21:30:04 -07:00
resource.c
rtc.c Merge branch 'x86-intel-mid-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-11-12 11:12:22 +09:00
setup.c Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-02 13:15:58 -07:00
setup_percpu.c
signal.c x86, vdso: Reimplement vdso.so preparation in build-time C 2014-05-05 13:18:51 -07:00
smp.c x86, asmlinkage: Make all interrupt handlers asmlinkage / __visible 2013-08-06 14:18:23 -07:00
smpboot.c Merge branch 'x86-threadinfo-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-01 10:17:18 -07:00
stacktrace.c
step.c ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL 2013-01-22 10:08:00 -08:00
sys_x86_64.c x86 get_unmapped_area: Access mmap_legacy_base through mm_struct member 2013-08-22 10:19:35 -07:00
syscall_32.c x86, asmlinkage: Make syscall tables visible 2013-08-06 14:20:18 -07:00
syscall_64.c x86, asmlinkage: Make syscall tables visible 2013-08-06 14:20:18 -07:00
sysfb.c x86: sysfb: move EFI quirks from efifb to sysfb 2013-08-02 16:17:47 -07:00
sysfb_efi.c x86: sysfb: move EFI quirks from efifb to sysfb 2013-08-02 16:17:47 -07:00
sysfb_simplefb.c x86/simplefb: Mark framebuffer mem-resources as IORESOURCE_BUSY to avoid bootup warning 2013-10-03 07:51:11 +02:00
tboot.c x86 / tboot / ACPI: Fail extended mode reduced hardware sleep 2013-07-31 14:25:51 +02:00
tce_64.c
test_nx.c
test_rodata.c
time.c Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-01 11:22:57 -07:00
tls.c make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect 2013-03-03 22:58:33 -05:00
tls.h
topology.c hotplug, powerpc, x86: Remove cpu_hotplug_driver_lock() 2013-09-30 19:55:51 +02:00
trace_clock.c
tracepoint.c x86: Make sure IDT is page aligned 2013-07-16 15:14:48 -07:00
traps.c x86/traps: Clean up error exception handler definitions 2013-12-12 14:46:42 +01:00
tsc.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-02 12:26:43 -07:00
tsc_msr.c x86: tsc: Add missing Baytrail frequency to the table 2014-02-19 17:12:24 +01:00
tsc_sync.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
uprobes.c uretprobes/x86: Hijack return address 2013-04-13 15:31:55 +02:00
verify_cpu.S
vm86_32.c x86, vm86: fix VM86 syscalls: use SYSCALL_DEFINEx(...) 2013-05-02 20:36:32 -04:00
vmlinux.lds.S x86, vdso: Zero-pad the VVAR page 2014-03-18 12:52:44 -07:00
vsmp_64.c x86/vsmp: Fix irq routing 2014-04-28 09:27:34 +02:00
vsyscall_64.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
vsyscall_emu_64.S
vsyscall_gtod.c x86, vdso: Add 32 bit VDSO time support for 64 bit kernel 2014-03-18 12:52:41 -07:00
vsyscall_trace.h
x86_init.c PCI: Drop "irq" param from *_restore_msi_irqs() 2013-12-13 08:44:30 -07:00
x8664_ksyms_64.c sched, x86: Optimize the preempt_schedule() call 2013-09-25 14:23:07 +02:00
xsave.c x86, xsave: Support eager-only xsave features, add MPX support 2013-12-06 17:17:42 -08:00