Re: [GIT PULL] x86/vdso changes for v3.1
From: Arnaud Lacombe
Date: Thu Aug 25 2011 - 01:59:00 EST
Hi,
On Fri, Jul 22, 2011 at 11:42 AM, Ingo Molnar <mingo@xxxxxxx> wrote:
> Linus,
>
> Please pull the latest x86-vdso-for-linus git tree from:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86-vdso-for-linus
>
>
> out-of-topic modifications in x86-vdso-for-linus:
> -------------------------------------------------
> arch/ia64/Kconfig # ae7bd11: clocksource: Change __ARCH_HAS_CL
> arch/ia64/include/asm/clocksource.h# ae7bd11: clocksource: Change __ARCH_HAS_CL
> # 574c44f: ia64: Replace clocksource.fsys_mm
> arch/ia64/kernel/cyclone.c # 574c44f: ia64: Replace clocksource.fsys_mm
> arch/ia64/kernel/time.c # 574c44f: ia64: Replace clocksource.fsys_mm
> arch/ia64/sn/kernel/sn2/timer.c # 574c44f: ia64: Replace clocksource.fsys_mm
> drivers/char/hpet.c # 574c44f: ia64: Replace clocksource.fsys_mm
> include/linux/clocksource.h # ae7bd11: clocksource: Change __ARCH_HAS_CL
> # 574c44f: ia64: Replace clocksource.fsys_mm
> # 433bd80: clocksource: Replace vread with g
> include/linux/seccomp.h # 5cec93c: x86-64: Emulate legacy vsyscalls
>
> Thanks,
>
> Ingo
>
> ------------------>
> Andy Lutomirski (17):
> x86-64: Fix alignment of jiffies variable
> x86-64: Document some of entry_64.S
> x86-64: Give vvars their own page
> x86-64: Remove kernel.vsyscall64 sysctl
> x86-64: Map the HPET NX
> x86-64: Remove vsyscall number 3 (venosys)
> x86-64: Fill unused parts of the vsyscall page with 0xcc
> x86-64: Emulate legacy vsyscalls
> x86-64: Improve vsyscall emulation CS and RIP handling
> x86: Make alternative instruction pointers relative
Bisecting this BUG:
CPU: Intel QEMU Virtual CPU version 0.13.0 stepping 03
BUG: unable to handle kernel paging request at 8277e54c
IP: [<c13765fb>] apply_alternatives+0xc3/0x18a
*pde = 00000000
Oops: 0000 [#1] DEBUG_PAGEALLOC
Pid: 0, comm: swapper Not tainted 3.1.0-rc3 #20 Bochs Bochs
EIP: 0060:[<c13765fb>] EFLAGS: 00000286 CPU: 0
EIP is at apply_alternatives+0xc3/0x18a
EAX: ffffffff EBX: c13bee40 ECX: 00000005 EDX: 8277e54c
ESI: 8277e54c EDI: c1349e9e EBP: c1349fa8 ESP: c1349e70
DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
Process swapper (pid: 0, ti=c1348000 task=c134e340 task.ti=c1348000)
Stack:
00000002 c135d7c0 c11418a0 00000db8 c1349e9e 82655b12 00000005 8277e54c
c13bf6ec c1349e05 05000086 f6890046 00f69000 c1349eb0 00000086 00000000
00000046 c1349ec0 00000046 00000000 c1349edc c101f29c 00000dc5 00000000
Call Trace:
[<c11418a0>] ? serial8250_start_tx+0xe0/0xe0
[<c101f29c>] ? console_unlock+0x10c/0x150
[<c10039c3>] ? do_IRQ+0x43/0xa0
[<c12975a9>] ? common_interrupt+0x29/0x30
[<c1294d59>] ? printk+0x18/0x1f
[<c139070b>] ? print_cpu_info+0x93/0x11f
[<c13766d9>] alternative_instructions+0x17/0x32
[<c1377552>] check_bugs+0x91/0x93
[<c13716b6>] start_kernel+0x289/0x294
[<c13711b7>] ? loglevel+0x1a/0x1a
[<c13710b3>] i386_start_kernel+0xb3/0xbb
Code: ec fe ff ff 8d 0c 0b 89 8d dc fe ff ff 8d 54 13 04 8b bd d8 fe
ff ff 89 95 e4 fe ff ff 89 b5 e0 fe ff ff 8b 8d e0 fe ff ff 89 d6 <f3>
a4 80 bd f6 fe ff ff e8 75 17 80 bd ec fe ff ff 05 75 0e 89
EIP: [<c13765fb>] apply_alternatives+0xc3/0x18a SS:ESP 0068:c1349e70
CR2: 000000008277e54c
---[ end trace 4eaa2a86a8e2da22 ]---
Kernel panic - not syncing: Attempted to kill the idle task!
Pid: 0, comm: swapper Tainted: G D 3.1.0-rc3 #20
Call Trace:
[<c1294d59>] ? printk+0x18/0x1f
[<c1294c4a>] panic+0x57/0x14e
[<c10221a1>] do_exit+0x201/0x290
[<c1004ace>] oops_end+0x6e/0x90
[<c1294d59>] ? printk+0x18/0x1f
[<c1013efc>] no_context+0xbc/0x150
[<c1013fc0>] __bad_area_nosemaphore+0x30/0x170
[<c1014450>] ? vmalloc_sync_all+0xf0/0xf0
[<c1014112>] bad_area_nosemaphore+0x12/0x20
[<c101466f>] do_page_fault+0x21f/0x360
[<c105c070>] ? get_page_from_freelist+0x110/0x300
[<c1023b24>] ? irq_exit+0x54/0x90
[<c10039c3>] ? do_IRQ+0x43/0xa0
[<c1140e31>] ? wait_for_xmitr+0x31/0x90
[<c1014450>] ? vmalloc_sync_all+0xf0/0xf0
[<c1296df8>] error_code+0x58/0x60
[<c1014450>] ? vmalloc_sync_all+0xf0/0xf0
[<c13765fb>] ? apply_alternatives+0xc3/0x18a
[<c11418a0>] ? serial8250_start_tx+0xe0/0xe0
[<c101f29c>] ? console_unlock+0x10c/0x150
[<c10039c3>] ? do_IRQ+0x43/0xa0
[<c12975a9>] ? common_interrupt+0x29/0x30
[<c1294d59>] ? printk+0x18/0x1f
[<c139070b>] ? print_cpu_info+0x93/0x11f
[<c13766d9>] alternative_instructions+0x17/0x32
[<c1377552>] check_bugs+0x91/0x93
[<c13716b6>] start_kernel+0x289/0x294
[<c13711b7>] ? loglevel+0x1a/0x1a
[<c13710b3>] i386_start_kernel+0xb3/0xbb
QEMU: Terminated
lead me to that commit:
commit 59e97e4d6fbcd5b74a94cb48bcbfc6f8478a5e93
Author: Andy Lutomirski <luto@xxxxxxx>
Date: Wed Jul 13 09:24:10 2011 -0400
x86: Make alternative instruction pointers relative
This save a few bytes on x86-64 and means that future patches can
apply alternatives to unrelocated code.
Signed-off-by: Andy Lutomirski <luto@xxxxxxx>
Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@xxxxxxx
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
Here is the bisection log:
% git bisect log
git bisect start
# bad: [3ef706459b940b49e37a62c8ec720728c7260b49] acpi/acpi_drivers.h:
fix warnings when ACPI_DOCK is not enabled
this first step is an un-merged local change from next-20110824.
git bisect bad 3ef706459b940b49e37a62c8ec720728c7260b49
# bad: [fcb8ce5cfe30ca9ca5c9a79cdfe26d1993e65e0c] Linux 3.1-rc3
git bisect bad fcb8ce5cfe30ca9ca5c9a79cdfe26d1993e65e0c
# good: [02f8c6aee8df3cdc935e9bdd4f2d020306035dbe] Linux 3.0
git bisect good 02f8c6aee8df3cdc935e9bdd4f2d020306035dbe
# bad: [d272281c390eb6c3f1e70ed0337c9e619d99cd9c] [SCSI] fcoe: cleanup
cpu selection for incoming requests
git bisect bad d272281c390eb6c3f1e70ed0337c9e619d99cd9c
# good: [f9035cd498486d5a82ad8ae9bcfdb91b3e57ec9d] Merge branch
'for-davem' of ssh://master.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6
git bisect good f9035cd498486d5a82ad8ae9bcfdb91b3e57ec9d
# bad: [c61264f98c1a974ee6f545f61a4ab33b141d6bda] Merge branch
'upstream/xen-tracing2' of
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
git bisect bad c61264f98c1a974ee6f545f61a4ab33b141d6bda
# bad: [9d1c02135516866cbbb2f80e20cfb65c63a3ce40] Merge branch
'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
git bisect bad 9d1c02135516866cbbb2f80e20cfb65c63a3ce40
# good: [112ec469663e09ffc815761254b52f3ca787ce83] Merge branch
'timers-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
git bisect good 112ec469663e09ffc815761254b52f3ca787ce83
# good: [5a9a43646cf709312d71eca71cef90ad802f28f9] vfs: use ERR_CAST
for err-ptr tossing in lookup_instantiate_filp
git bisect good 5a9a43646cf709312d71eca71cef90ad802f28f9
# good: [805120795947008612ef64618bba8a6aa30cf88b] Merge branch
'x86-signal-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
git bisect good 805120795947008612ef64618bba8a6aa30cf88b
# bad: [e660a828f017991468ce322742586e8ebb047ae6] 9p: clean up packet dump code
git bisect bad e660a828f017991468ce322742586e8ebb047ae6
# bad: [8c400f6ce068366bc3517f1036bb99169cfec9cd] x86, vdso: Drop now
wrong comment
git bisect bad 8c400f6ce068366bc3517f1036bb99169cfec9cd
# good: [5cec93c216db77c45f7ce970d46283bcb1933884] x86-64: Emulate
legacy vsyscalls
git bisect good 5cec93c216db77c45f7ce970d46283bcb1933884
# bad: [7f79ad15f33cf4968cafb0e3d2beba427de01d3a] x86-64: Add
--no-undefined to vDSO build
git bisect bad 7f79ad15f33cf4968cafb0e3d2beba427de01d3a
# bad: [59e97e4d6fbcd5b74a94cb48bcbfc6f8478a5e93] x86: Make
alternative instruction pointers relative
git bisect bad 59e97e4d6fbcd5b74a94cb48bcbfc6f8478a5e93
# good: [c9712944b2a12373cb6ff8059afcfb7e826a6c54] x86-64: Improve
vsyscall emulation CS and RIP handling
git bisect good c9712944b2a12373cb6ff8059afcfb7e826a6c54
I'm trying a kernel with 59e97e4d6fb reverted on top of -rc3 to check.
Revert triggered a single conflict in `arch/x86/kernel/alternative.c'.
Config attached.
Thanks,
- Arnaud
> x86-64: Allow alternative patching in the vDSO
> x86-64: Add --no-undefined to vDSO build
> clocksource: Replace vread with generic arch data
> x86-64: Move vread_tsc and vread_hpet into the vDSO
> ia64: Replace clocksource.fsys_mmio with generic arch data
> Document the vDSO and add a reference parser
> x86-64, vdso: Do not allocate memory for the vDSO
>
> Borislav Petkov (1):
> x86, vdso: Drop now wrong comment
>
> H. Peter Anvin (1):
> clocksource: Change __ARCH_HAS_CLOCKSOURCE_DATA to a CONFIG option
>
>
> Documentation/ABI/stable/vdso | 27 +++
> Documentation/vDSO/parse_vdso.c | 256 ++++++++++++++++++++++++++
> Documentation/vDSO/vdso_test.c | 111 ++++++++++++
> Documentation/x86/entry_64.txt | 98 ++++++++++
> arch/ia64/Kconfig | 3 +
> arch/ia64/include/asm/clocksource.h | 10 +
> arch/ia64/kernel/cyclone.c | 2 +-
> arch/ia64/kernel/time.c | 2 +-
> arch/ia64/sn/kernel/sn2/timer.c | 2 +-
> arch/x86/Kconfig | 4 +
> arch/x86/include/asm/alternative-asm.h | 4 +-
> arch/x86/include/asm/alternative.h | 8 +-
> arch/x86/include/asm/clocksource.h | 18 ++
> arch/x86/include/asm/cpufeature.h | 8 +-
> arch/x86/include/asm/fixmap.h | 1 +
> arch/x86/include/asm/irq_vectors.h | 6 +-
> arch/x86/include/asm/pgtable_types.h | 6 +-
> arch/x86/include/asm/traps.h | 4 +
> arch/x86/include/asm/tsc.h | 4 -
> arch/x86/include/asm/vgtod.h | 3 +-
> arch/x86/include/asm/vsyscall.h | 4 -
> arch/x86/include/asm/vvar.h | 24 ++--
> arch/x86/kernel/Makefile | 8 +-
> arch/x86/kernel/alternative.c | 23 +--
> arch/x86/kernel/entry_64.S | 4 +
> arch/x86/kernel/hpet.c | 11 +-
> arch/x86/kernel/traps.c | 6 +
> arch/x86/kernel/tsc.c | 2 +-
> arch/x86/kernel/vmlinux.lds.S | 49 +++---
> arch/x86/kernel/vread_tsc_64.c | 36 ----
> arch/x86/kernel/vsyscall_64.c | 310 +++++++++++++++-----------------
> arch/x86/kernel/vsyscall_emu_64.S | 27 +++
> arch/x86/lib/copy_page_64.S | 9 +-
> arch/x86/lib/memmove_64.S | 11 +-
> arch/x86/vdso/Makefile | 1 +
> arch/x86/vdso/vclock_gettime.c | 103 +++++++----
> arch/x86/vdso/vdso.S | 15 ++-
> arch/x86/vdso/vma.c | 58 ++++--
> drivers/char/hpet.c | 2 +-
> include/linux/clocksource.h | 15 +-
> include/linux/seccomp.h | 10 +
> 41 files changed, 927 insertions(+), 378 deletions(-)
> create mode 100644 Documentation/ABI/stable/vdso
> create mode 100644 Documentation/vDSO/parse_vdso.c
> create mode 100644 Documentation/vDSO/vdso_test.c
> create mode 100644 Documentation/x86/entry_64.txt
> create mode 100644 arch/ia64/include/asm/clocksource.h
> create mode 100644 arch/x86/include/asm/clocksource.h
> delete mode 100644 arch/x86/kernel/vread_tsc_64.c
> create mode 100644 arch/x86/kernel/vsyscall_emu_64.S
>
> diff --git a/Documentation/ABI/stable/vdso b/Documentation/ABI/stable/vdso
> new file mode 100644
> index 0000000..8a1cbb5
> --- /dev/null
> +++ b/Documentation/ABI/stable/vdso
> @@ -0,0 +1,27 @@
> +On some architectures, when the kernel loads any userspace program it
> +maps an ELF DSO into that program's address space. This DSO is called
> +the vDSO and it often contains useful and highly-optimized alternatives
> +to real syscalls.
> +
> +These functions are called just like ordinary C function according to
> +your platform's ABI. Call them from a sensible context. (For example,
> +if you set CS on x86 to something strange, the vDSO functions are
> +within their rights to crash.) In addition, if you pass a bad
> +pointer to a vDSO function, you might get SIGSEGV instead of -EFAULT.
> +
> +To find the DSO, parse the auxiliary vector passed to the program's
> +entry point. The AT_SYSINFO_EHDR entry will point to the vDSO.
> +
> +The vDSO uses symbol versioning; whenever you request a symbol from the
> +vDSO, specify the version you are expecting.
> +
> +Programs that dynamically link to glibc will use the vDSO automatically.
> +Otherwise, you can use the reference parser in Documentation/vDSO/parse_vdso.c.
> +
> +Unless otherwise noted, the set of symbols with any given version and the
> +ABI of those symbols is considered stable. It may vary across architectures,
> +though.
> +
> +(As of this writing, this ABI documentation as been confirmed for x86_64.
> + The maintainers of the other vDSO-using architectures should confirm
> + that it is correct for their architecture.)
> \ No newline at end of file
> diff --git a/Documentation/vDSO/parse_vdso.c b/Documentation/vDSO/parse_vdso.c
> new file mode 100644
> index 0000000..8587020
> --- /dev/null
> +++ b/Documentation/vDSO/parse_vdso.c
> @@ -0,0 +1,256 @@
> +/*
> + * parse_vdso.c: Linux reference vDSO parser
> + * Written by Andrew Lutomirski, 2011.
> + *
> + * This code is meant to be linked in to various programs that run on Linux.
> + * As such, it is available with as few restrictions as possible. This file
> + * is licensed under the Creative Commons Zero License, version 1.0,
> + * available at http://creativecommons.org/publicdomain/zero/1.0/legalcode
> + *
> + * The vDSO is a regular ELF DSO that the kernel maps into user space when
> + * it starts a program. It works equally well in statically and dynamically
> + * linked binaries.
> + *
> + * This code is tested on x86_64. In principle it should work on any 64-bit
> + * architecture that has a vDSO.
> + */
> +
> +#include <stdbool.h>
> +#include <stdint.h>
> +#include <string.h>
> +#include <elf.h>
> +
> +/*
> + * To use this vDSO parser, first call one of the vdso_init_* functions.
> + * If you've already parsed auxv, then pass the value of AT_SYSINFO_EHDR
> + * to vdso_init_from_sysinfo_ehdr. Otherwise pass auxv to vdso_init_from_auxv.
> + * Then call vdso_sym for each symbol you want. For example, to look up
> + * gettimeofday on x86_64, use:
> + *
> + * <some pointer> = vdso_sym("LINUX_2.6", "gettimeofday");
> + * or
> + * <some pointer> = vdso_sym("LINUX_2.6", "__vdso_gettimeofday");
> + *
> + * vdso_sym will return 0 if the symbol doesn't exist or if the init function
> + * failed or was not called. vdso_sym is a little slow, so its return value
> + * should be cached.
> + *
> + * vdso_sym is threadsafe; the init functions are not.
> + *
> + * These are the prototypes:
> + */
> +extern void vdso_init_from_auxv(void *auxv);
> +extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);
> +extern void *vdso_sym(const char *version, const char *name);
> +
> +
> +/* And here's the code. */
> +
> +#ifndef __x86_64__
> +# error Not yet ported to non-x86_64 architectures
> +#endif
> +
> +static struct vdso_info
> +{
> + bool valid;
> +
> + /* Load information */
> + uintptr_t load_addr;
> + uintptr_t load_offset; /* load_addr - recorded vaddr */
> +
> + /* Symbol table */
> + Elf64_Sym *symtab;
> + const char *symstrings;
> + Elf64_Word *bucket, *chain;
> + Elf64_Word nbucket, nchain;
> +
> + /* Version table */
> + Elf64_Versym *versym;
> + Elf64_Verdef *verdef;
> +} vdso_info;
> +
> +/* Straight from the ELF specification. */
> +static unsigned long elf_hash(const unsigned char *name)
> +{
> + unsigned long h = 0, g;
> + while (*name)
> + {
> + h = (h << 4) + *name++;
> + if (g = h & 0xf0000000)
> + h ^= g >> 24;
> + h &= ~g;
> + }
> + return h;
> +}
> +
> +void vdso_init_from_sysinfo_ehdr(uintptr_t base)
> +{
> + size_t i;
> + bool found_vaddr = false;
> +
> + vdso_info.valid = false;
> +
> + vdso_info.load_addr = base;
> +
> + Elf64_Ehdr *hdr = (Elf64_Ehdr*)base;
> + Elf64_Phdr *pt = (Elf64_Phdr*)(vdso_info.load_addr + hdr->e_phoff);
> + Elf64_Dyn *dyn = 0;
> +
> + /*
> + * We need two things from the segment table: the load offset
> + * and the dynamic table.
> + */
> + for (i = 0; i < hdr->e_phnum; i++)
> + {
> + if (pt[i].p_type == PT_LOAD && !found_vaddr) {
> + found_vaddr = true;
> + vdso_info.load_offset = base
> + + (uintptr_t)pt[i].p_offset
> + - (uintptr_t)pt[i].p_vaddr;
> + } else if (pt[i].p_type == PT_DYNAMIC) {
> + dyn = (Elf64_Dyn*)(base + pt[i].p_offset);
> + }
> + }
> +
> + if (!found_vaddr || !dyn)
> + return; /* Failed */
> +
> + /*
> + * Fish out the useful bits of the dynamic table.
> + */
> + Elf64_Word *hash = 0;
> + vdso_info.symstrings = 0;
> + vdso_info.symtab = 0;
> + vdso_info.versym = 0;
> + vdso_info.verdef = 0;
> + for (i = 0; dyn[i].d_tag != DT_NULL; i++) {
> + switch (dyn[i].d_tag) {
> + case DT_STRTAB:
> + vdso_info.symstrings = (const char *)
> + ((uintptr_t)dyn[i].d_un.d_ptr
> + + vdso_info.load_offset);
> + break;
> + case DT_SYMTAB:
> + vdso_info.symtab = (Elf64_Sym *)
> + ((uintptr_t)dyn[i].d_un.d_ptr
> + + vdso_info.load_offset);
> + break;
> + case DT_HASH:
> + hash = (Elf64_Word *)
> + ((uintptr_t)dyn[i].d_un.d_ptr
> + + vdso_info.load_offset);
> + break;
> + case DT_VERSYM:
> + vdso_info.versym = (Elf64_Versym *)
> + ((uintptr_t)dyn[i].d_un.d_ptr
> + + vdso_info.load_offset);
> + break;
> + case DT_VERDEF:
> + vdso_info.verdef = (Elf64_Verdef *)
> + ((uintptr_t)dyn[i].d_un.d_ptr
> + + vdso_info.load_offset);
> + break;
> + }
> + }
> + if (!vdso_info.symstrings || !vdso_info.symtab || !hash)
> + return; /* Failed */
> +
> + if (!vdso_info.verdef)
> + vdso_info.versym = 0;
> +
> + /* Parse the hash table header. */
> + vdso_info.nbucket = hash[0];
> + vdso_info.nchain = hash[1];
> + vdso_info.bucket = &hash[2];
> + vdso_info.chain = &hash[vdso_info.nbucket + 2];
> +
> + /* That's all we need. */
> + vdso_info.valid = true;
> +}
> +
> +static bool vdso_match_version(Elf64_Versym ver,
> + const char *name, Elf64_Word hash)
> +{
> + /*
> + * This is a helper function to check if the version indexed by
> + * ver matches name (which hashes to hash).
> + *
> + * The version definition table is a mess, and I don't know how
> + * to do this in better than linear time without allocating memory
> + * to build an index. I also don't know why the table has
> + * variable size entries in the first place.
> + *
> + * For added fun, I can't find a comprehensible specification of how
> + * to parse all the weird flags in the table.
> + *
> + * So I just parse the whole table every time.
> + */
> +
> + /* First step: find the version definition */
> + ver &= 0x7fff; /* Apparently bit 15 means "hidden" */
> + Elf64_Verdef *def = vdso_info.verdef;
> + while(true) {
> + if ((def->vd_flags & VER_FLG_BASE) == 0
> + && (def->vd_ndx & 0x7fff) == ver)
> + break;
> +
> + if (def->vd_next == 0)
> + return false; /* No definition. */
> +
> + def = (Elf64_Verdef *)((char *)def + def->vd_next);
> + }
> +
> + /* Now figure out whether it matches. */
> + Elf64_Verdaux *aux = (Elf64_Verdaux*)((char *)def + def->vd_aux);
> + return def->vd_hash == hash
> + && !strcmp(name, vdso_info.symstrings + aux->vda_name);
> +}
> +
> +void *vdso_sym(const char *version, const char *name)
> +{
> + unsigned long ver_hash;
> + if (!vdso_info.valid)
> + return 0;
> +
> + ver_hash = elf_hash(version);
> + Elf64_Word chain = vdso_info.bucket[elf_hash(name) % vdso_info.nbucket];
> +
> + for (; chain != STN_UNDEF; chain = vdso_info.chain[chain]) {
> + Elf64_Sym *sym = &vdso_info.symtab[chain];
> +
> + /* Check for a defined global or weak function w/ right name. */
> + if (ELF64_ST_TYPE(sym->st_info) != STT_FUNC)
> + continue;
> + if (ELF64_ST_BIND(sym->st_info) != STB_GLOBAL &&
> + ELF64_ST_BIND(sym->st_info) != STB_WEAK)
> + continue;
> + if (sym->st_shndx == SHN_UNDEF)
> + continue;
> + if (strcmp(name, vdso_info.symstrings + sym->st_name))
> + continue;
> +
> + /* Check symbol version. */
> + if (vdso_info.versym
> + && !vdso_match_version(vdso_info.versym[chain],
> + version, ver_hash))
> + continue;
> +
> + return (void *)(vdso_info.load_offset + sym->st_value);
> + }
> +
> + return 0;
> +}
> +
> +void vdso_init_from_auxv(void *auxv)
> +{
> + Elf64_auxv_t *elf_auxv = auxv;
> + for (int i = 0; elf_auxv[i].a_type != AT_NULL; i++)
> + {
> + if (elf_auxv[i].a_type == AT_SYSINFO_EHDR) {
> + vdso_init_from_sysinfo_ehdr(elf_auxv[i].a_un.a_val);
> + return;
> + }
> + }
> +
> + vdso_info.valid = false;
> +}
> diff --git a/Documentation/vDSO/vdso_test.c b/Documentation/vDSO/vdso_test.c
> new file mode 100644
> index 0000000..fff6334
> --- /dev/null
> +++ b/Documentation/vDSO/vdso_test.c
> @@ -0,0 +1,111 @@
> +/*
> + * vdso_test.c: Sample code to test parse_vdso.c on x86_64
> + * Copyright (c) 2011 Andy Lutomirski
> + * Subject to the GNU General Public License, version 2
> + *
> + * You can amuse yourself by compiling with:
> + * gcc -std=gnu99 -nostdlib
> + * -Os -fno-asynchronous-unwind-tables -flto
> + * vdso_test.c parse_vdso.c -o vdso_test
> + * to generate a small binary with no dependencies at all.
> + */
> +
> +#include <sys/syscall.h>
> +#include <sys/time.h>
> +#include <unistd.h>
> +#include <stdint.h>
> +
> +extern void *vdso_sym(const char *version, const char *name);
> +extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);
> +extern void vdso_init_from_auxv(void *auxv);
> +
> +/* We need a libc functions... */
> +int strcmp(const char *a, const char *b)
> +{
> + /* This implementation is buggy: it never returns -1. */
> + while (*a || *b) {
> + if (*a != *b)
> + return 1;
> + if (*a == 0 || *b == 0)
> + return 1;
> + a++;
> + b++;
> + }
> +
> + return 0;
> +}
> +
> +/* ...and two syscalls. This is x86_64-specific. */
> +static inline long linux_write(int fd, const void *data, size_t len)
> +{
> +
> + long ret;
> + asm volatile ("syscall" : "=a" (ret) : "a" (__NR_write),
> + "D" (fd), "S" (data), "d" (len) :
> + "cc", "memory", "rcx",
> + "r8", "r9", "r10", "r11" );
> + return ret;
> +}
> +
> +static inline void linux_exit(int code)
> +{
> + asm volatile ("syscall" : : "a" (__NR_exit), "D" (code));
> +}
> +
> +void to_base10(char *lastdig, uint64_t n)
> +{
> + while (n) {
> + *lastdig = (n % 10) + '0';
> + n /= 10;
> + lastdig--;
> + }
> +}
> +
> +__attribute__((externally_visible)) void c_main(void **stack)
> +{
> + /* Parse the stack */
> + long argc = (long)*stack;
> + stack += argc + 2;
> +
> + /* Now we're pointing at the environment. Skip it. */
> + while(*stack)
> + stack++;
> + stack++;
> +
> + /* Now we're pointing at auxv. Initialize the vDSO parser. */
> + vdso_init_from_auxv((void *)stack);
> +
> + /* Find gettimeofday. */
> + typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
> + gtod_t gtod = (gtod_t)vdso_sym("LINUX_2.6", "__vdso_gettimeofday");
> +
> + if (!gtod)
> + linux_exit(1);
> +
> + struct timeval tv;
> + long ret = gtod(&tv, 0);
> +
> + if (ret == 0) {
> + char buf[] = "The time is .000000\n";
> + to_base10(buf + 31, tv.tv_sec);
> + to_base10(buf + 38, tv.tv_usec);
> + linux_write(1, buf, sizeof(buf) - 1);
> + } else {
> + linux_exit(ret);
> + }
> +
> + linux_exit(0);
> +}
> +
> +/*
> + * This is the real entry point. It passes the initial stack into
> + * the C entry point.
> + */
> +asm (
> + ".text\n"
> + ".global _start\n"
> + ".type _start,@function\n"
> + "_start:\n\t"
> + "mov %rsp,%rdi\n\t"
> + "jmp c_main"
> + );
> diff --git a/Documentation/x86/entry_64.txt b/Documentation/x86/entry_64.txt
> new file mode 100644
> index 0000000..7869f14
> --- /dev/null
> +++ b/Documentation/x86/entry_64.txt
> @@ -0,0 +1,98 @@
> +This file documents some of the kernel entries in
> +arch/x86/kernel/entry_64.S. A lot of this explanation is adapted from
> +an email from Ingo Molnar:
> +
> +http://lkml.kernel.org/r/<20110529191055.GC9835%40elte.hu>
> +
> +The x86 architecture has quite a few different ways to jump into
> +kernel code. Most of these entry points are registered in
> +arch/x86/kernel/traps.c and implemented in arch/x86/kernel/entry_64.S
> +and arch/x86/ia32/ia32entry.S.
> +
> +The IDT vector assignments are listed in arch/x86/include/irq_vectors.h.
> +
> +Some of these entries are:
> +
> + - system_call: syscall instruction from 64-bit code.
> +
> + - ia32_syscall: int 0x80 from 32-bit or 64-bit code; compat syscall
> + either way.
> +
> + - ia32_syscall, ia32_sysenter: syscall and sysenter from 32-bit
> + code
> +
> + - interrupt: An array of entries. Every IDT vector that doesn't
> + explicitly point somewhere else gets set to the corresponding
> + value in interrupts. These point to a whole array of
> + magically-generated functions that make their way to do_IRQ with
> + the interrupt number as a parameter.
> +
> + - emulate_vsyscall: int 0xcc, a special non-ABI entry used by
> + vsyscall emulation.
> +
> + - APIC interrupts: Various special-purpose interrupts for things
> + like TLB shootdown.
> +
> + - Architecturally-defined exceptions like divide_error.
> +
> +There are a few complexities here. The different x86-64 entries
> +have different calling conventions. The syscall and sysenter
> +instructions have their own peculiar calling conventions. Some of
> +the IDT entries push an error code onto the stack; others don't.
> +IDT entries using the IST alternative stack mechanism need their own
> +magic to get the stack frames right. (You can find some
> +documentation in the AMD APM, Volume 2, Chapter 8 and the Intel SDM,
> +Volume 3, Chapter 6.)
> +
> +Dealing with the swapgs instruction is especially tricky. Swapgs
> +toggles whether gs is the kernel gs or the user gs. The swapgs
> +instruction is rather fragile: it must nest perfectly and only in
> +single depth, it should only be used if entering from user mode to
> +kernel mode and then when returning to user-space, and precisely
> +so. If we mess that up even slightly, we crash.
> +
> +So when we have a secondary entry, already in kernel mode, we *must
> +not* use SWAPGS blindly - nor must we forget doing a SWAPGS when it's
> +not switched/swapped yet.
> +
> +Now, there's a secondary complication: there's a cheap way to test
> +which mode the CPU is in and an expensive way.
> +
> +The cheap way is to pick this info off the entry frame on the kernel
> +stack, from the CS of the ptregs area of the kernel stack:
> +
> + xorl %ebx,%ebx
> + testl $3,CS+8(%rsp)
> + je error_kernelspace
> + SWAPGS
> +
> +The expensive (paranoid) way is to read back the MSR_GS_BASE value
> +(which is what SWAPGS modifies):
> +
> + movl $1,%ebx
> + movl $MSR_GS_BASE,%ecx
> + rdmsr
> + testl %edx,%edx
> + js 1f /* negative -> in kernel */
> + SWAPGS
> + xorl %ebx,%ebx
> +1: ret
> +
> +and the whole paranoid non-paranoid macro complexity is about whether
> +to suffer that RDMSR cost.
> +
> +If we are at an interrupt or user-trap/gate-alike boundary then we can
> +use the faster check: the stack will be a reliable indicator of
> +whether SWAPGS was already done: if we see that we are a secondary
> +entry interrupting kernel mode execution, then we know that the GS
> +base has already been switched. If it says that we interrupted
> +user-space execution then we must do the SWAPGS.
> +
> +But if we are in an NMI/MCE/DEBUG/whatever super-atomic entry context,
> +which might have triggered right after a normal entry wrote CS to the
> +stack but before we executed SWAPGS, then the only safe way to check
> +for GS is the slower method: the RDMSR.
> +
> +So we try only to mark those entry methods 'paranoid' that absolutely
> +need the more expensive check for the GS base - and we generate all
> +'normal' entry points with the regular (faster) entry macros.
> diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
> index 38280ef..0a9820a 100644
> --- a/arch/ia64/Kconfig
> +++ b/arch/ia64/Kconfig
> @@ -101,6 +101,9 @@ config GENERIC_IOMAP
> bool
> default y
>
> +config ARCH_CLOCKSOURCE_DATA
> + def_bool y
> +
> config SCHED_OMIT_FRAME_POINTER
> bool
> default y
> diff --git a/arch/ia64/include/asm/clocksource.h b/arch/ia64/include/asm/clocksource.h
> new file mode 100644
> index 0000000..5c8596e
> --- /dev/null
> +++ b/arch/ia64/include/asm/clocksource.h
> @@ -0,0 +1,10 @@
> +/* IA64-specific clocksource additions */
> +
> +#ifndef _ASM_IA64_CLOCKSOURCE_H
> +#define _ASM_IA64_CLOCKSOURCE_H
> +
> +struct arch_clocksource_data {
> + void *fsys_mmio; /* used by fsyscall asm code */
> +};
> +
> +#endif /* _ASM_IA64_CLOCKSOURCE_H */
> diff --git a/arch/ia64/kernel/cyclone.c b/arch/ia64/kernel/cyclone.c
> index f64097b..4826ff9 100644
> --- a/arch/ia64/kernel/cyclone.c
> +++ b/arch/ia64/kernel/cyclone.c
> @@ -115,7 +115,7 @@ int __init init_cyclone_clock(void)
> }
> /* initialize last tick */
> cyclone_mc = cyclone_timer;
> - clocksource_cyclone.fsys_mmio = cyclone_timer;
> + clocksource_cyclone.archdata.fsys_mmio = cyclone_timer;
> clocksource_register_hz(&clocksource_cyclone, CYCLONE_TIMER_FREQ);
>
> return 0;
> diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
> index 85118df..43920de 100644
> --- a/arch/ia64/kernel/time.c
> +++ b/arch/ia64/kernel/time.c
> @@ -468,7 +468,7 @@ void update_vsyscall(struct timespec *wall, struct timespec *wtm,
> fsyscall_gtod_data.clk_mask = c->mask;
> fsyscall_gtod_data.clk_mult = mult;
> fsyscall_gtod_data.clk_shift = c->shift;
> - fsyscall_gtod_data.clk_fsys_mmio = c->fsys_mmio;
> + fsyscall_gtod_data.clk_fsys_mmio = c->archdata.fsys_mmio;
> fsyscall_gtod_data.clk_cycle_last = c->cycle_last;
>
> /* copy kernel time structures */
> diff --git a/arch/ia64/sn/kernel/sn2/timer.c b/arch/ia64/sn/kernel/sn2/timer.c
> index c34efda..0f8844e 100644
> --- a/arch/ia64/sn/kernel/sn2/timer.c
> +++ b/arch/ia64/sn/kernel/sn2/timer.c
> @@ -54,7 +54,7 @@ ia64_sn_udelay (unsigned long usecs)
>
> void __init sn_timer_init(void)
> {
> - clocksource_sn2.fsys_mmio = RTC_COUNTER_ADDR;
> + clocksource_sn2.archdata.fsys_mmio = RTC_COUNTER_ADDR;
> clocksource_register_hz(&clocksource_sn2, sn_rtc_cycles_per_second);
>
> ia64_udelay = &ia64_sn_udelay;
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index da34972..c1e41bc 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -93,6 +93,10 @@ config CLOCKSOURCE_WATCHDOG
> config GENERIC_CLOCKEVENTS
> def_bool y
>
> +config ARCH_CLOCKSOURCE_DATA
> + def_bool y
> + depends on X86_64
> +
> config GENERIC_CLOCKEVENTS_BROADCAST
> def_bool y
> depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
> diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h
> index 94d420b..4554cc6 100644
> --- a/arch/x86/include/asm/alternative-asm.h
> +++ b/arch/x86/include/asm/alternative-asm.h
> @@ -17,8 +17,8 @@
>
> .macro altinstruction_entry orig alt feature orig_len alt_len
> .align 8
> - .quad \orig
> - .quad \alt
> + .long \orig - .
> + .long \alt - .
> .word \feature
> .byte \orig_len
> .byte \alt_len
> diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
> index bf535f9..23fb6d7 100644
> --- a/arch/x86/include/asm/alternative.h
> +++ b/arch/x86/include/asm/alternative.h
> @@ -43,8 +43,8 @@
> #endif
>
> struct alt_instr {
> - u8 *instr; /* original instruction */
> - u8 *replacement;
> + s32 instr_offset; /* original instruction */
> + s32 repl_offset; /* offset to replacement instruction */
> u16 cpuid; /* cpuid bit set for replacement */
> u8 instrlen; /* length of original instruction */
> u8 replacementlen; /* length of new instruction, <= instrlen */
> @@ -84,8 +84,8 @@ static inline int alternatives_text_reserved(void *start, void *end)
> "661:\n\t" oldinstr "\n662:\n" \
> ".section .altinstructions,\"a\"\n" \
> _ASM_ALIGN "\n" \
> - _ASM_PTR "661b\n" /* label */ \
> - _ASM_PTR "663f\n" /* new instruction */ \
> + " .long 661b - .\n" /* label */ \
> + " .long 663f - .\n" /* new instruction */ \
> " .word " __stringify(feature) "\n" /* feature bit */ \
> " .byte 662b-661b\n" /* sourcelen */ \
> " .byte 664f-663f\n" /* replacementlen */ \
> diff --git a/arch/x86/include/asm/clocksource.h b/arch/x86/include/asm/clocksource.h
> new file mode 100644
> index 0000000..0bdbbb3
> --- /dev/null
> +++ b/arch/x86/include/asm/clocksource.h
> @@ -0,0 +1,18 @@
> +/* x86-specific clocksource additions */
> +
> +#ifndef _ASM_X86_CLOCKSOURCE_H
> +#define _ASM_X86_CLOCKSOURCE_H
> +
> +#ifdef CONFIG_X86_64
> +
> +#define VCLOCK_NONE 0 /* No vDSO clock available. */
> +#define VCLOCK_TSC 1 /* vDSO should use vread_tsc. */
> +#define VCLOCK_HPET 2 /* vDSO should use vread_hpet. */
> +
> +struct arch_clocksource_data {
> + int vclock_mode;
> +};
> +
> +#endif /* CONFIG_X86_64 */
> +
> +#endif /* _ASM_X86_CLOCKSOURCE_H */
> diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
> index 71cc380..9929b35 100644
> --- a/arch/x86/include/asm/cpufeature.h
> +++ b/arch/x86/include/asm/cpufeature.h
> @@ -331,8 +331,8 @@ static __always_inline __pure bool __static_cpu_has(u16 bit)
> "2:\n"
> ".section .altinstructions,\"a\"\n"
> _ASM_ALIGN "\n"
> - _ASM_PTR "1b\n"
> - _ASM_PTR "0\n" /* no replacement */
> + " .long 1b - .\n"
> + " .long 0\n" /* no replacement */
> " .word %P0\n" /* feature bit */
> " .byte 2b - 1b\n" /* source len */
> " .byte 0\n" /* replacement len */
> @@ -349,8 +349,8 @@ static __always_inline __pure bool __static_cpu_has(u16 bit)
> "2:\n"
> ".section .altinstructions,\"a\"\n"
> _ASM_ALIGN "\n"
> - _ASM_PTR "1b\n"
> - _ASM_PTR "3f\n"
> + " .long 1b - .\n"
> + " .long 3f - .\n"
> " .word %P1\n" /* feature bit */
> " .byte 2b - 1b\n" /* source len */
> " .byte 4f - 3f\n" /* replacement len */
> diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
> index 4729b2b..460c74e 100644
> --- a/arch/x86/include/asm/fixmap.h
> +++ b/arch/x86/include/asm/fixmap.h
> @@ -78,6 +78,7 @@ enum fixed_addresses {
> VSYSCALL_LAST_PAGE,
> VSYSCALL_FIRST_PAGE = VSYSCALL_LAST_PAGE
> + ((VSYSCALL_END-VSYSCALL_START) >> PAGE_SHIFT) - 1,
> + VVAR_PAGE,
> VSYSCALL_HPET,
> #endif
> FIX_DBGP_BASE,
> diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
> index 6e976ee..a563c50 100644
> --- a/arch/x86/include/asm/irq_vectors.h
> +++ b/arch/x86/include/asm/irq_vectors.h
> @@ -17,7 +17,8 @@
> * Vectors 0 ... 31 : system traps and exceptions - hardcoded events
> * Vectors 32 ... 127 : device interrupts
> * Vector 128 : legacy int80 syscall interface
> - * Vectors 129 ... INVALIDATE_TLB_VECTOR_START-1 : device interrupts
> + * Vector 204 : legacy x86_64 vsyscall emulation
> + * Vectors 129 ... INVALIDATE_TLB_VECTOR_START-1 except 204 : device interrupts
> * Vectors INVALIDATE_TLB_VECTOR_START ... 255 : special interrupts
> *
> * 64-bit x86 has per CPU IDT tables, 32-bit has one shared IDT table.
> @@ -50,6 +51,9 @@
> #ifdef CONFIG_X86_32
> # define SYSCALL_VECTOR 0x80
> #endif
> +#ifdef CONFIG_X86_64
> +# define VSYSCALL_EMU_VECTOR 0xcc
> +#endif
>
> /*
> * Vectors 0x30-0x3f are used for ISA interrupts.
> diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
> index d56187c..013286a 100644
> --- a/arch/x86/include/asm/pgtable_types.h
> +++ b/arch/x86/include/asm/pgtable_types.h
> @@ -107,7 +107,8 @@
> #define __PAGE_KERNEL_NOCACHE (__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
> #define __PAGE_KERNEL_UC_MINUS (__PAGE_KERNEL | _PAGE_PCD)
> #define __PAGE_KERNEL_VSYSCALL (__PAGE_KERNEL_RX | _PAGE_USER)
> -#define __PAGE_KERNEL_VSYSCALL_NOCACHE (__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
> +#define __PAGE_KERNEL_VVAR (__PAGE_KERNEL_RO | _PAGE_USER)
> +#define __PAGE_KERNEL_VVAR_NOCACHE (__PAGE_KERNEL_VVAR | _PAGE_PCD | _PAGE_PWT)
> #define __PAGE_KERNEL_LARGE (__PAGE_KERNEL | _PAGE_PSE)
> #define __PAGE_KERNEL_LARGE_NOCACHE (__PAGE_KERNEL | _PAGE_CACHE_UC | _PAGE_PSE)
> #define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE)
> @@ -129,7 +130,8 @@
> #define PAGE_KERNEL_LARGE_NOCACHE __pgprot(__PAGE_KERNEL_LARGE_NOCACHE)
> #define PAGE_KERNEL_LARGE_EXEC __pgprot(__PAGE_KERNEL_LARGE_EXEC)
> #define PAGE_KERNEL_VSYSCALL __pgprot(__PAGE_KERNEL_VSYSCALL)
> -#define PAGE_KERNEL_VSYSCALL_NOCACHE __pgprot(__PAGE_KERNEL_VSYSCALL_NOCACHE)
> +#define PAGE_KERNEL_VVAR __pgprot(__PAGE_KERNEL_VVAR)
> +#define PAGE_KERNEL_VVAR_NOCACHE __pgprot(__PAGE_KERNEL_VVAR_NOCACHE)
>
> #define PAGE_KERNEL_IO __pgprot(__PAGE_KERNEL_IO)
> #define PAGE_KERNEL_IO_NOCACHE __pgprot(__PAGE_KERNEL_IO_NOCACHE)
> diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
> index 0310da6..2bae0a5 100644
> --- a/arch/x86/include/asm/traps.h
> +++ b/arch/x86/include/asm/traps.h
> @@ -1,6 +1,8 @@
> #ifndef _ASM_X86_TRAPS_H
> #define _ASM_X86_TRAPS_H
>
> +#include <linux/kprobes.h>
> +
> #include <asm/debugreg.h>
> #include <asm/siginfo.h> /* TRAP_TRACE, ... */
>
> @@ -38,6 +40,7 @@ asmlinkage void alignment_check(void);
> asmlinkage void machine_check(void);
> #endif /* CONFIG_X86_MCE */
> asmlinkage void simd_coprocessor_error(void);
> +asmlinkage void emulate_vsyscall(void);
>
> dotraplinkage void do_divide_error(struct pt_regs *, long);
> dotraplinkage void do_debug(struct pt_regs *, long);
> @@ -64,6 +67,7 @@ dotraplinkage void do_alignment_check(struct pt_regs *, long);
> dotraplinkage void do_machine_check(struct pt_regs *, long);
> #endif
> dotraplinkage void do_simd_coprocessor_error(struct pt_regs *, long);
> +dotraplinkage void do_emulate_vsyscall(struct pt_regs *, long);
> #ifdef CONFIG_X86_32
> dotraplinkage void do_iret_error(struct pt_regs *, long);
> #endif
> diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
> index 9db5583..83e2efd 100644
> --- a/arch/x86/include/asm/tsc.h
> +++ b/arch/x86/include/asm/tsc.h
> @@ -51,10 +51,6 @@ extern int unsynchronized_tsc(void);
> extern int check_tsc_unstable(void);
> extern unsigned long native_calibrate_tsc(void);
>
> -#ifdef CONFIG_X86_64
> -extern cycles_t vread_tsc(void);
> -#endif
> -
> /*
> * Boot-time check whether the TSCs are synchronized across
> * all CPUs/cores:
> diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h
> index 646b4c1..815285b 100644
> --- a/arch/x86/include/asm/vgtod.h
> +++ b/arch/x86/include/asm/vgtod.h
> @@ -11,10 +11,9 @@ struct vsyscall_gtod_data {
> time_t wall_time_sec;
> u32 wall_time_nsec;
>
> - int sysctl_enabled;
> struct timezone sys_tz;
> struct { /* extract of a clocksource struct */
> - cycle_t (*vread)(void);
> + int vclock_mode;
> cycle_t cycle_last;
> cycle_t mask;
> u32 mult;
> diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h
> index d555973..6010707 100644
> --- a/arch/x86/include/asm/vsyscall.h
> +++ b/arch/x86/include/asm/vsyscall.h
> @@ -16,10 +16,6 @@ enum vsyscall_num {
> #ifdef __KERNEL__
> #include <linux/seqlock.h>
>
> -/* Definitions for CONFIG_GENERIC_TIME definitions */
> -#define __vsyscall_fn \
> - __attribute__ ((unused, __section__(".vsyscall_fn"))) notrace
> -
> #define VGETCPU_RDTSCP 1
> #define VGETCPU_LSL 2
>
> diff --git a/arch/x86/include/asm/vvar.h b/arch/x86/include/asm/vvar.h
> index 341b355..de656ac 100644
> --- a/arch/x86/include/asm/vvar.h
> +++ b/arch/x86/include/asm/vvar.h
> @@ -10,15 +10,14 @@
> * In normal kernel code, they are used like any other variable.
> * In user code, they are accessed through the VVAR macro.
> *
> - * Each of these variables lives in the vsyscall page, and each
> - * one needs a unique offset within the little piece of the page
> - * reserved for vvars. Specify that offset in DECLARE_VVAR.
> - * (There are 896 bytes available. If you mess up, the linker will
> - * catch it.)
> + * These variables live in a page of kernel data that has an extra RO
> + * mapping for userspace. Each variable needs a unique offset within
> + * that page; specify that offset with the DECLARE_VVAR macro. (If
> + * you mess up, the linker will catch it.)
> */
>
> -/* Offset of vars within vsyscall page */
> -#define VSYSCALL_VARS_OFFSET (3072 + 128)
> +/* Base address of vvars. This is not ABI. */
> +#define VVAR_ADDRESS (-10*1024*1024 - 4096)
>
> #if defined(__VVAR_KERNEL_LDS)
>
> @@ -26,17 +25,17 @@
> * right place.
> */
> #define DECLARE_VVAR(offset, type, name) \
> - EMIT_VVAR(name, VSYSCALL_VARS_OFFSET + offset)
> + EMIT_VVAR(name, offset)
>
> #else
>
> #define DECLARE_VVAR(offset, type, name) \
> static type const * const vvaraddr_ ## name = \
> - (void *)(VSYSCALL_START + VSYSCALL_VARS_OFFSET + (offset));
> + (void *)(VVAR_ADDRESS + (offset));
>
> #define DEFINE_VVAR(type, name) \
> - type __vvar_ ## name \
> - __attribute__((section(".vsyscall_var_" #name), aligned(16)))
> + type name \
> + __attribute__((section(".vvar_" #name), aligned(16)))
>
> #define VVAR(name) (*vvaraddr_ ## name)
>
> @@ -45,8 +44,7 @@
> /* DECLARE_VVAR(offset, type, name) */
>
> DECLARE_VVAR(0, volatile unsigned long, jiffies)
> -DECLARE_VVAR(8, int, vgetcpu_mode)
> +DECLARE_VVAR(16, int, vgetcpu_mode)
> DECLARE_VVAR(128, struct vsyscall_gtod_data, vsyscall_gtod_data)
>
> #undef DECLARE_VVAR
> -#undef VSYSCALL_VARS_OFFSET
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index 90b06d4..2deef3d 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -24,17 +24,12 @@ endif
> nostackp := $(call cc-option, -fno-stack-protector)
> CFLAGS_vsyscall_64.o := $(PROFILING) -g0 $(nostackp)
> CFLAGS_hpet.o := $(nostackp)
> -CFLAGS_vread_tsc_64.o := $(nostackp)
> CFLAGS_paravirt.o := $(nostackp)
> GCOV_PROFILE_vsyscall_64.o := n
> GCOV_PROFILE_hpet.o := n
> GCOV_PROFILE_tsc.o := n
> -GCOV_PROFILE_vread_tsc_64.o := n
> GCOV_PROFILE_paravirt.o := n
>
> -# vread_tsc_64 is hot and should be fully optimized:
> -CFLAGS_REMOVE_vread_tsc_64.o = -pg -fno-optimize-sibling-calls
> -
> obj-y := process_$(BITS).o signal.o entry_$(BITS).o
> obj-y += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
> obj-y += time.o ioport.o ldt.o dumpstack.o
> @@ -43,7 +38,8 @@ obj-$(CONFIG_IRQ_WORK) += irq_work.o
> obj-y += probe_roms.o
> obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o
> obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o
> -obj-$(CONFIG_X86_64) += syscall_64.o vsyscall_64.o vread_tsc_64.o
> +obj-$(CONFIG_X86_64) += syscall_64.o vsyscall_64.o
> +obj-$(CONFIG_X86_64) += vsyscall_emu_64.o
> obj-y += bootflag.o e820.o
> obj-y += pci-dma.o quirks.o topology.o kdebugfs.o
> obj-y += alternative.o i8253.o pci-nommu.o hw_breakpoint.o
> diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
> index a81f2d5..c638228 100644
> --- a/arch/x86/kernel/alternative.c
> +++ b/arch/x86/kernel/alternative.c
> @@ -14,7 +14,6 @@
> #include <asm/pgtable.h>
> #include <asm/mce.h>
> #include <asm/nmi.h>
> -#include <asm/vsyscall.h>
> #include <asm/cacheflush.h>
> #include <asm/tlbflush.h>
> #include <asm/io.h>
> @@ -250,7 +249,6 @@ static void __init_or_module add_nops(void *insns, unsigned int len)
>
> extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
> extern s32 __smp_locks[], __smp_locks_end[];
> -extern char __vsyscall_0;
> void *text_poke_early(void *addr, const void *opcode, size_t len);
>
> /* Replace instructions with better alternatives for this CPU type.
> @@ -263,6 +261,7 @@ void __init_or_module apply_alternatives(struct alt_instr *start,
> struct alt_instr *end)
> {
> struct alt_instr *a;
> + u8 *instr, *replacement;
> u8 insnbuf[MAX_PATCH_LEN];
>
> DPRINTK("%s: alt table %p -> %p\n", __func__, start, end);
> @@ -276,25 +275,23 @@ void __init_or_module apply_alternatives(struct alt_instr *start,
> * order.
> */
> for (a = start; a < end; a++) {
> - u8 *instr = a->instr;
> + instr = (u8 *)&a->instr_offset + a->instr_offset;
> + replacement = (u8 *)&a->repl_offset + a->repl_offset;
> BUG_ON(a->replacementlen > a->instrlen);
> BUG_ON(a->instrlen > sizeof(insnbuf));
> BUG_ON(a->cpuid >= NCAPINTS*32);
> if (!boot_cpu_has(a->cpuid))
> continue;
> -#ifdef CONFIG_X86_64
> - /* vsyscall code is not mapped yet. resolve it manually. */
> - if (instr >= (u8 *)VSYSCALL_START && instr < (u8*)VSYSCALL_END) {
> - instr = __va(instr - (u8*)VSYSCALL_START + (u8*)__pa_symbol(&__vsyscall_0));
> - DPRINTK("%s: vsyscall fixup: %p => %p\n",
> - __func__, a->instr, instr);
> - }
> -#endif
> - memcpy(insnbuf, a->replacement, a->replacementlen);
> +
> + memcpy(insnbuf, replacement, a->replacementlen);
> +
> + /* 0xe8 is a relative jump; fix the offset. */
> if (*insnbuf == 0xe8 && a->replacementlen == 5)
> - *(s32 *)(insnbuf + 1) += a->replacement - a->instr;
> + *(s32 *)(insnbuf + 1) += replacement - instr;
> +
> add_nops(insnbuf + a->replacementlen,
> a->instrlen - a->replacementlen);
> +
> text_poke_early(instr, insnbuf, a->instrlen);
> }
> }
> diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
> index 8a445a0..e949793 100644
> --- a/arch/x86/kernel/entry_64.S
> +++ b/arch/x86/kernel/entry_64.S
> @@ -9,6 +9,8 @@
> /*
> * entry.S contains the system-call and fault low-level handling routines.
> *
> + * Some of this is documented in Documentation/x86/entry_64.txt
> + *
> * NOTE: This code handles signal-recognition, which happens every time
> * after an interrupt and after each system call.
> *
> @@ -1121,6 +1123,8 @@ zeroentry spurious_interrupt_bug do_spurious_interrupt_bug
> zeroentry coprocessor_error do_coprocessor_error
> errorentry alignment_check do_alignment_check
> zeroentry simd_coprocessor_error do_simd_coprocessor_error
> +zeroentry emulate_vsyscall do_emulate_vsyscall
> +
>
> /* Reload gs selector with exception handling */
> /* edi: new selector */
> diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
> index 6781765..d10cc00 100644
> --- a/arch/x86/kernel/hpet.c
> +++ b/arch/x86/kernel/hpet.c
> @@ -71,7 +71,7 @@ static inline void hpet_set_mapping(void)
> {
> hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
> #ifdef CONFIG_X86_64
> - __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
> + __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VVAR_NOCACHE);
> #endif
> }
>
> @@ -738,13 +738,6 @@ static cycle_t read_hpet(struct clocksource *cs)
> return (cycle_t)hpet_readl(HPET_COUNTER);
> }
>
> -#ifdef CONFIG_X86_64
> -static cycle_t __vsyscall_fn vread_hpet(void)
> -{
> - return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 0xf0);
> -}
> -#endif
> -
> static struct clocksource clocksource_hpet = {
> .name = "hpet",
> .rating = 250,
> @@ -753,7 +746,7 @@ static struct clocksource clocksource_hpet = {
> .flags = CLOCK_SOURCE_IS_CONTINUOUS,
> .resume = hpet_resume_counter,
> #ifdef CONFIG_X86_64
> - .vread = vread_hpet,
> + .archdata = { .vclock_mode = VCLOCK_HPET },
> #endif
> };
>
> diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
> index b9b6716..fbc097a 100644
> --- a/arch/x86/kernel/traps.c
> +++ b/arch/x86/kernel/traps.c
> @@ -872,6 +872,12 @@ void __init trap_init(void)
> set_bit(SYSCALL_VECTOR, used_vectors);
> #endif
>
> +#ifdef CONFIG_X86_64
> + BUG_ON(test_bit(VSYSCALL_EMU_VECTOR, used_vectors));
> + set_system_intr_gate(VSYSCALL_EMU_VECTOR, &emulate_vsyscall);
> + set_bit(VSYSCALL_EMU_VECTOR, used_vectors);
> +#endif
> +
> /*
> * Should be a barrier for any external CPU state:
> */
> diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
> index 6cc6922..56c633a 100644
> --- a/arch/x86/kernel/tsc.c
> +++ b/arch/x86/kernel/tsc.c
> @@ -777,7 +777,7 @@ static struct clocksource clocksource_tsc = {
> .flags = CLOCK_SOURCE_IS_CONTINUOUS |
> CLOCK_SOURCE_MUST_VERIFY,
> #ifdef CONFIG_X86_64
> - .vread = vread_tsc,
> + .archdata = { .vclock_mode = VCLOCK_TSC },
> #endif
> };
>
> diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
> index 89aed99..4aa9c54 100644
> --- a/arch/x86/kernel/vmlinux.lds.S
> +++ b/arch/x86/kernel/vmlinux.lds.S
> @@ -161,50 +161,47 @@ SECTIONS
>
> #define VVIRT_OFFSET (VSYSCALL_ADDR - __vsyscall_0)
> #define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
> -#define EMIT_VVAR(x, offset) .vsyscall_var_ ## x \
> - ADDR(.vsyscall_0) + offset \
> - : AT(VLOAD(.vsyscall_var_ ## x)) { \
> - *(.vsyscall_var_ ## x) \
> - } \
> - x = VVIRT(.vsyscall_var_ ## x);
>
> . = ALIGN(4096);
> __vsyscall_0 = .;
>
> . = VSYSCALL_ADDR;
> - .vsyscall_0 : AT(VLOAD(.vsyscall_0)) {
> + .vsyscall : AT(VLOAD(.vsyscall)) {
> *(.vsyscall_0)
> - } :user
>
> - . = ALIGN(L1_CACHE_BYTES);
> - .vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
> - *(.vsyscall_fn)
> - }
> -
> - .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) {
> + . = 1024;
> *(.vsyscall_1)
> - }
> - .vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) {
> - *(.vsyscall_2)
> - }
>
> - .vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) {
> - *(.vsyscall_3)
> - }
> -
> -#define __VVAR_KERNEL_LDS
> -#include <asm/vvar.h>
> -#undef __VVAR_KERNEL_LDS
> + . = 2048;
> + *(.vsyscall_2)
>
> - . = __vsyscall_0 + PAGE_SIZE;
> + . = 4096; /* Pad the whole page. */
> + } :user =0xcc
> + . = ALIGN(__vsyscall_0 + PAGE_SIZE, PAGE_SIZE);
>
> #undef VSYSCALL_ADDR
> #undef VLOAD_OFFSET
> #undef VLOAD
> #undef VVIRT_OFFSET
> #undef VVIRT
> +
> + __vvar_page = .;
> +
> + .vvar : AT(ADDR(.vvar) - LOAD_OFFSET) {
> +
> + /* Place all vvars at the offsets in asm/vvar.h. */
> +#define EMIT_VVAR(name, offset) \
> + . = offset; \
> + *(.vvar_ ## name)
> +#define __VVAR_KERNEL_LDS
> +#include <asm/vvar.h>
> +#undef __VVAR_KERNEL_LDS
> #undef EMIT_VVAR
>
> + } :data
> +
> + . = ALIGN(__vvar_page + PAGE_SIZE, PAGE_SIZE);
> +
> #endif /* CONFIG_X86_64 */
>
> /* Init code and data - will be freed after init */
> diff --git a/arch/x86/kernel/vread_tsc_64.c b/arch/x86/kernel/vread_tsc_64.c
> deleted file mode 100644
> index a81aa9e..0000000
> --- a/arch/x86/kernel/vread_tsc_64.c
> +++ /dev/null
> @@ -1,36 +0,0 @@
> -/* This code runs in userspace. */
> -
> -#define DISABLE_BRANCH_PROFILING
> -#include <asm/vgtod.h>
> -
> -notrace cycle_t __vsyscall_fn vread_tsc(void)
> -{
> - cycle_t ret;
> - u64 last;
> -
> - /*
> - * Empirically, a fence (of type that depends on the CPU)
> - * before rdtsc is enough to ensure that rdtsc is ordered
> - * with respect to loads. The various CPU manuals are unclear
> - * as to whether rdtsc can be reordered with later loads,
> - * but no one has ever seen it happen.
> - */
> - rdtsc_barrier();
> - ret = (cycle_t)vget_cycles();
> -
> - last = VVAR(vsyscall_gtod_data).clock.cycle_last;
> -
> - if (likely(ret >= last))
> - return ret;
> -
> - /*
> - * GCC likes to generate cmov here, but this branch is extremely
> - * predictable (it's just a funciton of time and the likely is
> - * very likely) and there's a data dependence, so force GCC
> - * to generate a branch instead. I don't barrier() because
> - * we don't actually need a barrier, and if this function
> - * ever gets inlined it will generate worse code.
> - */
> - asm volatile ("");
> - return last;
> -}
> diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c
> index 3e68218..dda7dff 100644
> --- a/arch/x86/kernel/vsyscall_64.c
> +++ b/arch/x86/kernel/vsyscall_64.c
> @@ -2,6 +2,8 @@
> * Copyright (C) 2001 Andrea Arcangeli <andrea@xxxxxxx> SuSE
> * Copyright 2003 Andi Kleen, SuSE Labs.
> *
> + * [ NOTE: this mechanism is now deprecated in favor of the vDSO. ]
> + *
> * Thanks to hpa@xxxxxxxxxxxxx for some useful hint.
> * Special thanks to Ingo Molnar for his early experience with
> * a different vsyscall implementation for Linux/IA32 and for the name.
> @@ -11,10 +13,9 @@
> * vsyscalls. One vsyscall can reserve more than 1 slot to avoid
> * jumping out of line if necessary. We cannot add more with this
> * mechanism because older kernels won't return -ENOSYS.
> - * If we want more than four we need a vDSO.
> *
> - * Note: the concept clashes with user mode linux. If you use UML and
> - * want per guest time just set the kernel.vsyscall64 sysctl to 0.
> + * Note: the concept clashes with user mode linux. UML users should
> + * use the vDSO.
> */
>
> /* Disable profiling for userspace code: */
> @@ -32,9 +33,12 @@
> #include <linux/cpu.h>
> #include <linux/smp.h>
> #include <linux/notifier.h>
> +#include <linux/syscalls.h>
> +#include <linux/ratelimit.h>
>
> #include <asm/vsyscall.h>
> #include <asm/pgtable.h>
> +#include <asm/compat.h>
> #include <asm/page.h>
> #include <asm/unistd.h>
> #include <asm/fixmap.h>
> @@ -44,16 +48,12 @@
> #include <asm/desc.h>
> #include <asm/topology.h>
> #include <asm/vgtod.h>
> -
> -#define __vsyscall(nr) \
> - __attribute__ ((unused, __section__(".vsyscall_" #nr))) notrace
> -#define __syscall_clobber "r11","cx","memory"
> +#include <asm/traps.h>
>
> DEFINE_VVAR(int, vgetcpu_mode);
> DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data) =
> {
> .lock = __SEQLOCK_UNLOCKED(__vsyscall_gtod_data.lock),
> - .sysctl_enabled = 1,
> };
>
> void update_vsyscall_tz(void)
> @@ -72,179 +72,149 @@ void update_vsyscall(struct timespec *wall_time, struct timespec *wtm,
> unsigned long flags;
>
> write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags);
> +
> /* copy vsyscall data */
> - vsyscall_gtod_data.clock.vread = clock->vread;
> - vsyscall_gtod_data.clock.cycle_last = clock->cycle_last;
> - vsyscall_gtod_data.clock.mask = clock->mask;
> - vsyscall_gtod_data.clock.mult = mult;
> - vsyscall_gtod_data.clock.shift = clock->shift;
> - vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec;
> - vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
> - vsyscall_gtod_data.wall_to_monotonic = *wtm;
> - vsyscall_gtod_data.wall_time_coarse = __current_kernel_time();
> + vsyscall_gtod_data.clock.vclock_mode = clock->archdata.vclock_mode;
> + vsyscall_gtod_data.clock.cycle_last = clock->cycle_last;
> + vsyscall_gtod_data.clock.mask = clock->mask;
> + vsyscall_gtod_data.clock.mult = mult;
> + vsyscall_gtod_data.clock.shift = clock->shift;
> + vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec;
> + vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
> + vsyscall_gtod_data.wall_to_monotonic = *wtm;
> + vsyscall_gtod_data.wall_time_coarse = __current_kernel_time();
> +
> write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
> }
>
> -/* RED-PEN may want to readd seq locking, but then the variable should be
> - * write-once.
> - */
> -static __always_inline void do_get_tz(struct timezone * tz)
> +static void warn_bad_vsyscall(const char *level, struct pt_regs *regs,
> + const char *message)
> {
> - *tz = VVAR(vsyscall_gtod_data).sys_tz;
> -}
> + static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST);
> + struct task_struct *tsk;
>
> -static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz)
> -{
> - int ret;
> - asm volatile("syscall"
> - : "=a" (ret)
> - : "0" (__NR_gettimeofday),"D" (tv),"S" (tz)
> - : __syscall_clobber );
> - return ret;
> -}
> + if (!show_unhandled_signals || !__ratelimit(&rs))
> + return;
>
> -static __always_inline long time_syscall(long *t)
> -{
> - long secs;
> - asm volatile("syscall"
> - : "=a" (secs)
> - : "0" (__NR_time),"D" (t) : __syscall_clobber);
> - return secs;
> -}
> + tsk = current;
>
> -static __always_inline void do_vgettimeofday(struct timeval * tv)
> -{
> - cycle_t now, base, mask, cycle_delta;
> - unsigned seq;
> - unsigned long mult, shift, nsec;
> - cycle_t (*vread)(void);
> - do {
> - seq = read_seqbegin(&VVAR(vsyscall_gtod_data).lock);
> -
> - vread = VVAR(vsyscall_gtod_data).clock.vread;
> - if (unlikely(!VVAR(vsyscall_gtod_data).sysctl_enabled ||
> - !vread)) {
> - gettimeofday(tv,NULL);
> - return;
> - }
> -
> - now = vread();
> - base = VVAR(vsyscall_gtod_data).clock.cycle_last;
> - mask = VVAR(vsyscall_gtod_data).clock.mask;
> - mult = VVAR(vsyscall_gtod_data).clock.mult;
> - shift = VVAR(vsyscall_gtod_data).clock.shift;
> -
> - tv->tv_sec = VVAR(vsyscall_gtod_data).wall_time_sec;
> - nsec = VVAR(vsyscall_gtod_data).wall_time_nsec;
> - } while (read_seqretry(&VVAR(vsyscall_gtod_data).lock, seq));
> -
> - /* calculate interval: */
> - cycle_delta = (now - base) & mask;
> - /* convert to nsecs: */
> - nsec += (cycle_delta * mult) >> shift;
> -
> - while (nsec >= NSEC_PER_SEC) {
> - tv->tv_sec += 1;
> - nsec -= NSEC_PER_SEC;
> - }
> - tv->tv_usec = nsec / NSEC_PER_USEC;
> + printk("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n",
> + level, tsk->comm, task_pid_nr(tsk),
> + message, regs->ip - 2, regs->cs,
> + regs->sp, regs->ax, regs->si, regs->di);
> }
>
> -int __vsyscall(0) vgettimeofday(struct timeval * tv, struct timezone * tz)
> +static int addr_to_vsyscall_nr(unsigned long addr)
> {
> - if (tv)
> - do_vgettimeofday(tv);
> - if (tz)
> - do_get_tz(tz);
> - return 0;
> -}
> + int nr;
>
> -/* This will break when the xtime seconds get inaccurate, but that is
> - * unlikely */
> -time_t __vsyscall(1) vtime(time_t *t)
> -{
> - unsigned seq;
> - time_t result;
> - if (unlikely(!VVAR(vsyscall_gtod_data).sysctl_enabled))
> - return time_syscall(t);
> + if ((addr & ~0xC00UL) != VSYSCALL_START)
> + return -EINVAL;
>
> - do {
> - seq = read_seqbegin(&VVAR(vsyscall_gtod_data).lock);
> + nr = (addr & 0xC00UL) >> 10;
> + if (nr >= 3)
> + return -EINVAL;
>
> - result = VVAR(vsyscall_gtod_data).wall_time_sec;
> + return nr;
> +}
>
> - } while (read_seqretry(&VVAR(vsyscall_gtod_data).lock, seq));
> +void dotraplinkage do_emulate_vsyscall(struct pt_regs *regs, long error_code)
> +{
> + struct task_struct *tsk;
> + unsigned long caller;
> + int vsyscall_nr;
> + long ret;
> +
> + local_irq_enable();
> +
> + /*
> + * Real 64-bit user mode code has cs == __USER_CS. Anything else
> + * is bogus.
> + */
> + if (regs->cs != __USER_CS) {
> + /*
> + * If we trapped from kernel mode, we might as well OOPS now
> + * instead of returning to some random address and OOPSing
> + * then.
> + */
> + BUG_ON(!user_mode(regs));
> +
> + /* Compat mode and non-compat 32-bit CS should both segfault. */
> + warn_bad_vsyscall(KERN_WARNING, regs,
> + "illegal int 0xcc from 32-bit mode");
> + goto sigsegv;
> + }
>
> - if (t)
> - *t = result;
> - return result;
> -}
> + /*
> + * x86-ism here: regs->ip points to the instruction after the int 0xcc,
> + * and int 0xcc is two bytes long.
> + */
> + vsyscall_nr = addr_to_vsyscall_nr(regs->ip - 2);
> + if (vsyscall_nr < 0) {
> + warn_bad_vsyscall(KERN_WARNING, regs,
> + "illegal int 0xcc (exploit attempt?)");
> + goto sigsegv;
> + }
>
> -/* Fast way to get current CPU and node.
> - This helps to do per node and per CPU caches in user space.
> - The result is not guaranteed without CPU affinity, but usually
> - works out because the scheduler tries to keep a thread on the same
> - CPU.
> + if (get_user(caller, (unsigned long __user *)regs->sp) != 0) {
> + warn_bad_vsyscall(KERN_WARNING, regs, "int 0xcc with bad stack (exploit attempt?)");
> + goto sigsegv;
> + }
>
> - tcache must point to a two element sized long array.
> - All arguments can be NULL. */
> -long __vsyscall(2)
> -vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
> -{
> - unsigned int p;
> - unsigned long j = 0;
> -
> - /* Fast cache - only recompute value once per jiffies and avoid
> - relatively costly rdtscp/cpuid otherwise.
> - This works because the scheduler usually keeps the process
> - on the same CPU and this syscall doesn't guarantee its
> - results anyways.
> - We do this here because otherwise user space would do it on
> - its own in a likely inferior way (no access to jiffies).
> - If you don't like it pass NULL. */
> - if (tcache && tcache->blob[0] == (j = VVAR(jiffies))) {
> - p = tcache->blob[1];
> - } else if (VVAR(vgetcpu_mode) == VGETCPU_RDTSCP) {
> - /* Load per CPU data from RDTSCP */
> - native_read_tscp(&p);
> - } else {
> - /* Load per CPU data from GDT */
> - asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG));
> + tsk = current;
> + if (seccomp_mode(&tsk->seccomp))
> + do_exit(SIGKILL);
> +
> + switch (vsyscall_nr) {
> + case 0:
> + ret = sys_gettimeofday(
> + (struct timeval __user *)regs->di,
> + (struct timezone __user *)regs->si);
> + break;
> +
> + case 1:
> + ret = sys_time((time_t __user *)regs->di);
> + break;
> +
> + case 2:
> + ret = sys_getcpu((unsigned __user *)regs->di,
> + (unsigned __user *)regs->si,
> + 0);
> + break;
> }
> - if (tcache) {
> - tcache->blob[0] = j;
> - tcache->blob[1] = p;
> +
> + if (ret == -EFAULT) {
> + /*
> + * Bad news -- userspace fed a bad pointer to a vsyscall.
> + *
> + * With a real vsyscall, that would have caused SIGSEGV.
> + * To make writing reliable exploits using the emulated
> + * vsyscalls harder, generate SIGSEGV here as well.
> + */
> + warn_bad_vsyscall(KERN_INFO, regs,
> + "vsyscall fault (exploit attempt?)");
> + goto sigsegv;
> }
> - if (cpu)
> - *cpu = p & 0xfff;
> - if (node)
> - *node = p >> 12;
> - return 0;
> -}
>
> -static long __vsyscall(3) venosys_1(void)
> -{
> - return -ENOSYS;
> -}
> + regs->ax = ret;
>
> -#ifdef CONFIG_SYSCTL
> -static ctl_table kernel_table2[] = {
> - { .procname = "vsyscall64",
> - .data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
> - .mode = 0644,
> - .proc_handler = proc_dointvec },
> - {}
> -};
> + /* Emulate a ret instruction. */
> + regs->ip = caller;
> + regs->sp += 8;
>
> -static ctl_table kernel_root_table2[] = {
> - { .procname = "kernel", .mode = 0555,
> - .child = kernel_table2 },
> - {}
> -};
> -#endif
> + local_irq_disable();
> + return;
> +
> +sigsegv:
> + regs->ip -= 2; /* The faulting instruction should be the int 0xcc. */
> + force_sig(SIGSEGV, current);
> + local_irq_disable();
> +}
>
> -/* Assume __initcall executes before all user space. Hopefully kmod
> - doesn't violate that. We'll find out if it does. */
> +/*
> + * Assume __initcall executes before all user space. Hopefully kmod
> + * doesn't violate that. We'll find out if it does.
> + */
> static void __cpuinit vsyscall_set_cpu(int cpu)
> {
> unsigned long d;
> @@ -255,13 +225,15 @@ static void __cpuinit vsyscall_set_cpu(int cpu)
> if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP))
> write_rdtscp_aux((node << 12) | cpu);
>
> - /* Store cpu number in limit so that it can be loaded quickly
> - in user space in vgetcpu.
> - 12 bits for the CPU and 8 bits for the node. */
> + /*
> + * Store cpu number in limit so that it can be loaded quickly
> + * in user space in vgetcpu. (12 bits for the CPU and 8 bits for the node)
> + */
> d = 0x0f40000000000ULL;
> d |= cpu;
> d |= (node & 0xf) << 12;
> d |= (node >> 4) << 48;
> +
> write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S);
> }
>
> @@ -275,8 +247,10 @@ static int __cpuinit
> cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
> {
> long cpu = (long)arg;
> +
> if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
> smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 1);
> +
> return NOTIFY_DONE;
> }
>
> @@ -284,25 +258,23 @@ void __init map_vsyscall(void)
> {
> extern char __vsyscall_0;
> unsigned long physaddr_page0 = __pa_symbol(&__vsyscall_0);
> + extern char __vvar_page;
> + unsigned long physaddr_vvar_page = __pa_symbol(&__vvar_page);
>
> /* Note that VSYSCALL_MAPPED_PAGES must agree with the code below. */
> __set_fixmap(VSYSCALL_FIRST_PAGE, physaddr_page0, PAGE_KERNEL_VSYSCALL);
> + __set_fixmap(VVAR_PAGE, physaddr_vvar_page, PAGE_KERNEL_VVAR);
> + BUILD_BUG_ON((unsigned long)__fix_to_virt(VVAR_PAGE) != (unsigned long)VVAR_ADDRESS);
> }
>
> static int __init vsyscall_init(void)
> {
> - BUG_ON(((unsigned long) &vgettimeofday !=
> - VSYSCALL_ADDR(__NR_vgettimeofday)));
> - BUG_ON((unsigned long) &vtime != VSYSCALL_ADDR(__NR_vtime));
> - BUG_ON((VSYSCALL_ADDR(0) != __fix_to_virt(VSYSCALL_FIRST_PAGE)));
> - BUG_ON((unsigned long) &vgetcpu != VSYSCALL_ADDR(__NR_vgetcpu));
> -#ifdef CONFIG_SYSCTL
> - register_sysctl_table(kernel_root_table2);
> -#endif
> + BUG_ON(VSYSCALL_ADDR(0) != __fix_to_virt(VSYSCALL_FIRST_PAGE));
> +
> on_each_cpu(cpu_vsyscall_init, NULL, 1);
> /* notifier priority > KVM */
> hotcpu_notifier(cpu_vsyscall_notifier, 30);
> +
> return 0;
> }
> -
> __initcall(vsyscall_init);
> diff --git a/arch/x86/kernel/vsyscall_emu_64.S b/arch/x86/kernel/vsyscall_emu_64.S
> new file mode 100644
> index 0000000..ffa845e
> --- /dev/null
> +++ b/arch/x86/kernel/vsyscall_emu_64.S
> @@ -0,0 +1,27 @@
> +/*
> + * vsyscall_emu_64.S: Vsyscall emulation page
> + *
> + * Copyright (c) 2011 Andy Lutomirski
> + *
> + * Subject to the GNU General Public License, version 2
> + */
> +
> +#include <linux/linkage.h>
> +#include <asm/irq_vectors.h>
> +
> +/* The unused parts of the page are filled with 0xcc by the linker script. */
> +
> +.section .vsyscall_0, "a"
> +ENTRY(vsyscall_0)
> + int $VSYSCALL_EMU_VECTOR
> +END(vsyscall_0)
> +
> +.section .vsyscall_1, "a"
> +ENTRY(vsyscall_1)
> + int $VSYSCALL_EMU_VECTOR
> +END(vsyscall_1)
> +
> +.section .vsyscall_2, "a"
> +ENTRY(vsyscall_2)
> + int $VSYSCALL_EMU_VECTOR
> +END(vsyscall_2)
> diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S
> index 6fec2d1..01c805b 100644
> --- a/arch/x86/lib/copy_page_64.S
> +++ b/arch/x86/lib/copy_page_64.S
> @@ -2,6 +2,7 @@
>
> #include <linux/linkage.h>
> #include <asm/dwarf2.h>
> +#include <asm/alternative-asm.h>
>
> ALIGN
> copy_page_c:
> @@ -110,10 +111,6 @@ ENDPROC(copy_page)
> 2:
> .previous
> .section .altinstructions,"a"
> - .align 8
> - .quad copy_page
> - .quad 1b
> - .word X86_FEATURE_REP_GOOD
> - .byte .Lcopy_page_end - copy_page
> - .byte 2b - 1b
> + altinstruction_entry copy_page, 1b, X86_FEATURE_REP_GOOD, \
> + .Lcopy_page_end-copy_page, 2b-1b
> .previous
> diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S
> index d0ec9c2..ee16461 100644
> --- a/arch/x86/lib/memmove_64.S
> +++ b/arch/x86/lib/memmove_64.S
> @@ -9,6 +9,7 @@
> #include <linux/linkage.h>
> #include <asm/dwarf2.h>
> #include <asm/cpufeature.h>
> +#include <asm/alternative-asm.h>
>
> #undef memmove
>
> @@ -214,11 +215,9 @@ ENTRY(memmove)
> .previous
>
> .section .altinstructions,"a"
> - .align 8
> - .quad .Lmemmove_begin_forward
> - .quad .Lmemmove_begin_forward_efs
> - .word X86_FEATURE_ERMS
> - .byte .Lmemmove_end_forward-.Lmemmove_begin_forward
> - .byte .Lmemmove_end_forward_efs-.Lmemmove_begin_forward_efs
> + altinstruction_entry .Lmemmove_begin_forward, \
> + .Lmemmove_begin_forward_efs,X86_FEATURE_ERMS, \
> + .Lmemmove_end_forward-.Lmemmove_begin_forward, \
> + .Lmemmove_end_forward_efs-.Lmemmove_begin_forward_efs
> .previous
> ENDPROC(memmove)
> diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
> index bef0bc9..5d17950 100644
> --- a/arch/x86/vdso/Makefile
> +++ b/arch/x86/vdso/Makefile
> @@ -26,6 +26,7 @@ targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)
> export CPPFLAGS_vdso.lds += -P -C
>
> VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
> + -Wl,--no-undefined \
> -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
>
> $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
> diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
> index a724905..6bc0e72 100644
> --- a/arch/x86/vdso/vclock_gettime.c
> +++ b/arch/x86/vdso/vclock_gettime.c
> @@ -6,7 +6,6 @@
> *
> * The code should have no internal unresolved relocations.
> * Check with readelf after changing.
> - * Also alternative() doesn't work.
> */
>
> /* Disable profiling for userspace code: */
> @@ -17,6 +16,7 @@
> #include <linux/time.h>
> #include <linux/string.h>
> #include <asm/vsyscall.h>
> +#include <asm/fixmap.h>
> #include <asm/vgtod.h>
> #include <asm/timex.h>
> #include <asm/hpet.h>
> @@ -25,6 +25,43 @@
>
> #define gtod (&VVAR(vsyscall_gtod_data))
>
> +notrace static cycle_t vread_tsc(void)
> +{
> + cycle_t ret;
> + u64 last;
> +
> + /*
> + * Empirically, a fence (of type that depends on the CPU)
> + * before rdtsc is enough to ensure that rdtsc is ordered
> + * with respect to loads. The various CPU manuals are unclear
> + * as to whether rdtsc can be reordered with later loads,
> + * but no one has ever seen it happen.
> + */
> + rdtsc_barrier();
> + ret = (cycle_t)vget_cycles();
> +
> + last = VVAR(vsyscall_gtod_data).clock.cycle_last;
> +
> + if (likely(ret >= last))
> + return ret;
> +
> + /*
> + * GCC likes to generate cmov here, but this branch is extremely
> + * predictable (it's just a funciton of time and the likely is
> + * very likely) and there's a data dependence, so force GCC
> + * to generate a branch instead. I don't barrier() because
> + * we don't actually need a barrier, and if this function
> + * ever gets inlined it will generate worse code.
> + */
> + asm volatile ("");
> + return last;
> +}
> +
> +static notrace cycle_t vread_hpet(void)
> +{
> + return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 0xf0);
> +}
> +
> notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
> {
> long ret;
> @@ -36,9 +73,12 @@ notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
> notrace static inline long vgetns(void)
> {
> long v;
> - cycles_t (*vread)(void);
> - vread = gtod->clock.vread;
> - v = (vread() - gtod->clock.cycle_last) & gtod->clock.mask;
> + cycles_t cycles;
> + if (gtod->clock.vclock_mode == VCLOCK_TSC)
> + cycles = vread_tsc();
> + else
> + cycles = vread_hpet();
> + v = (cycles - gtod->clock.cycle_last) & gtod->clock.mask;
> return (v * gtod->clock.mult) >> gtod->clock.shift;
> }
>
> @@ -116,21 +156,21 @@ notrace static noinline int do_monotonic_coarse(struct timespec *ts)
>
> notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
> {
> - if (likely(gtod->sysctl_enabled))
> - switch (clock) {
> - case CLOCK_REALTIME:
> - if (likely(gtod->clock.vread))
> - return do_realtime(ts);
> - break;
> - case CLOCK_MONOTONIC:
> - if (likely(gtod->clock.vread))
> - return do_monotonic(ts);
> - break;
> - case CLOCK_REALTIME_COARSE:
> - return do_realtime_coarse(ts);
> - case CLOCK_MONOTONIC_COARSE:
> - return do_monotonic_coarse(ts);
> - }
> + switch (clock) {
> + case CLOCK_REALTIME:
> + if (likely(gtod->clock.vclock_mode != VCLOCK_NONE))
> + return do_realtime(ts);
> + break;
> + case CLOCK_MONOTONIC:
> + if (likely(gtod->clock.vclock_mode != VCLOCK_NONE))
> + return do_monotonic(ts);
> + break;
> + case CLOCK_REALTIME_COARSE:
> + return do_realtime_coarse(ts);
> + case CLOCK_MONOTONIC_COARSE:
> + return do_monotonic_coarse(ts);
> + }
> +
> return vdso_fallback_gettime(clock, ts);
> }
> int clock_gettime(clockid_t, struct timespec *)
> @@ -139,7 +179,7 @@ int clock_gettime(clockid_t, struct timespec *)
> notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
> {
> long ret;
> - if (likely(gtod->sysctl_enabled && gtod->clock.vread)) {
> + if (likely(gtod->clock.vclock_mode != VCLOCK_NONE)) {
> if (likely(tv != NULL)) {
> BUILD_BUG_ON(offsetof(struct timeval, tv_usec) !=
> offsetof(struct timespec, tv_nsec) ||
> @@ -161,27 +201,14 @@ notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
> int gettimeofday(struct timeval *, struct timezone *)
> __attribute__((weak, alias("__vdso_gettimeofday")));
>
> -/* This will break when the xtime seconds get inaccurate, but that is
> - * unlikely */
> -
> -static __always_inline long time_syscall(long *t)
> -{
> - long secs;
> - asm volatile("syscall"
> - : "=a" (secs)
> - : "0" (__NR_time), "D" (t) : "cc", "r11", "cx", "memory");
> - return secs;
> -}
> -
> +/*
> + * This will break when the xtime seconds get inaccurate, but that is
> + * unlikely
> + */
> notrace time_t __vdso_time(time_t *t)
> {
> - time_t result;
> -
> - if (unlikely(!VVAR(vsyscall_gtod_data).sysctl_enabled))
> - return time_syscall(t);
> -
> /* This is atomic on x86_64 so we don't need any locks. */
> - result = ACCESS_ONCE(VVAR(vsyscall_gtod_data).wall_time_sec);
> + time_t result = ACCESS_ONCE(VVAR(vsyscall_gtod_data).wall_time_sec);
>
> if (t)
> *t = result;
> diff --git a/arch/x86/vdso/vdso.S b/arch/x86/vdso/vdso.S
> index 1d3aa6b..1b979c1 100644
> --- a/arch/x86/vdso/vdso.S
> +++ b/arch/x86/vdso/vdso.S
> @@ -1,10 +1,21 @@
> +#include <asm/page_types.h>
> +#include <linux/linkage.h>
> #include <linux/init.h>
>
> -__INITDATA
> +__PAGE_ALIGNED_DATA
>
> .globl vdso_start, vdso_end
> + .align PAGE_SIZE
> vdso_start:
> .incbin "arch/x86/vdso/vdso.so"
> vdso_end:
>
> -__FINIT
> +.previous
> +
> + .globl vdso_pages
> + .bss
> + .align 8
> + .type vdso_pages, @object
> +vdso_pages:
> + .zero (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE * 8
> + .size vdso_pages, .-vdso_pages
> diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
> index 7abd2be..316fbca 100644
> --- a/arch/x86/vdso/vma.c
> +++ b/arch/x86/vdso/vma.c
> @@ -14,41 +14,61 @@
> #include <asm/vgtod.h>
> #include <asm/proto.h>
> #include <asm/vdso.h>
> +#include <asm/page.h>
>
> unsigned int __read_mostly vdso_enabled = 1;
>
> extern char vdso_start[], vdso_end[];
> extern unsigned short vdso_sync_cpuid;
>
> -static struct page **vdso_pages;
> +extern struct page *vdso_pages[];
> static unsigned vdso_size;
>
> -static int __init init_vdso_vars(void)
> +static void __init patch_vdso(void *vdso, size_t len)
> +{
> + Elf64_Ehdr *hdr = vdso;
> + Elf64_Shdr *sechdrs, *alt_sec = 0;
> + char *secstrings;
> + void *alt_data;
> + int i;
> +
> + BUG_ON(len < sizeof(Elf64_Ehdr));
> + BUG_ON(memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0);
> +
> + sechdrs = (void *)hdr + hdr->e_shoff;
> + secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
> +
> + for (i = 1; i < hdr->e_shnum; i++) {
> + Elf64_Shdr *shdr = &sechdrs[i];
> + if (!strcmp(secstrings + shdr->sh_name, ".altinstructions")) {
> + alt_sec = shdr;
> + goto found;
> + }
> + }
> +
> + /* If we get here, it's probably a bug. */
> + pr_warning("patch_vdso: .altinstructions not found\n");
> + return; /* nothing to patch */
> +
> +found:
> + alt_data = (void *)hdr + alt_sec->sh_offset;
> + apply_alternatives(alt_data, alt_data + alt_sec->sh_size);
> +}
> +
> +static int __init init_vdso(void)
> {
> int npages = (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE;
> int i;
>
> + patch_vdso(vdso_start, vdso_end - vdso_start);
> +
> vdso_size = npages << PAGE_SHIFT;
> - vdso_pages = kmalloc(sizeof(struct page *) * npages, GFP_KERNEL);
> - if (!vdso_pages)
> - goto oom;
> - for (i = 0; i < npages; i++) {
> - struct page *p;
> - p = alloc_page(GFP_KERNEL);
> - if (!p)
> - goto oom;
> - vdso_pages[i] = p;
> - copy_page(page_address(p), vdso_start + i*PAGE_SIZE);
> - }
> + for (i = 0; i < npages; i++)
> + vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE);
>
> return 0;
> -
> - oom:
> - printk("Cannot allocate vdso\n");
> - vdso_enabled = 0;
> - return -ENOMEM;
> }
> -subsys_initcall(init_vdso_vars);
> +subsys_initcall(init_vdso);
>
> struct linux_binprm;
>
> diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
> index 051474c..0557651 100644
> --- a/drivers/char/hpet.c
> +++ b/drivers/char/hpet.c
> @@ -931,7 +931,7 @@ int hpet_alloc(struct hpet_data *hdp)
> #ifdef CONFIG_IA64
> if (!hpet_clocksource) {
> hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc;
> - CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr);
> + clocksource_hpet.archdata.fsys_mmio = hpet_mctr;
> clocksource_register_hz(&clocksource_hpet, hpetp->hp_tick_freq);
> hpetp->hp_clocksource = &clocksource_hpet;
> hpet_clocksource = &clocksource_hpet;
> diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
> index d4646b4..59ee970 100644
> --- a/include/linux/clocksource.h
> +++ b/include/linux/clocksource.h
> @@ -22,6 +22,10 @@
> typedef u64 cycle_t;
> struct clocksource;
>
> +#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
> +#include <asm/clocksource.h>
> +#endif
> +
> /**
> * struct cyclecounter - hardware abstraction for a free running counter
> * Provides completely state-free accessors to the underlying hardware.
> @@ -153,7 +157,7 @@ extern u64 timecounter_cyc2time(struct timecounter *tc,
> * @shift: cycle to nanosecond divisor (power of two)
> * @max_idle_ns: max idle time permitted by the clocksource (nsecs)
> * @flags: flags describing special properties
> - * @vread: vsyscall based read
> + * @archdata: arch-specific data
> * @suspend: suspend function for the clocksource, if necessary
> * @resume: resume function for the clocksource, if necessary
> */
> @@ -169,16 +173,13 @@ struct clocksource {
> u32 shift;
> u64 max_idle_ns;
>
> -#ifdef CONFIG_IA64
> - void *fsys_mmio; /* used by fsyscall asm code */
> -#define CLKSRC_FSYS_MMIO_SET(mmio, addr) ((mmio) = (addr))
> -#else
> -#define CLKSRC_FSYS_MMIO_SET(mmio, addr) do { } while (0)
> +#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
> + struct arch_clocksource_data archdata;
> #endif
> +
> const char *name;
> struct list_head list;
> int rating;
> - cycle_t (*vread)(void);
> int (*enable)(struct clocksource *cs);
> void (*disable)(struct clocksource *cs);
> unsigned long flags;
> diff --git a/include/linux/seccomp.h b/include/linux/seccomp.h
> index 167c333..cc7a4e9 100644
> --- a/include/linux/seccomp.h
> +++ b/include/linux/seccomp.h
> @@ -19,6 +19,11 @@ static inline void secure_computing(int this_syscall)
> extern long prctl_get_seccomp(void);
> extern long prctl_set_seccomp(unsigned long);
>
> +static inline int seccomp_mode(seccomp_t *s)
> +{
> + return s->mode;
> +}
> +
> #else /* CONFIG_SECCOMP */
>
> #include <linux/errno.h>
> @@ -37,6 +42,11 @@ static inline long prctl_set_seccomp(unsigned long arg2)
> return -EINVAL;
> }
>
> +static inline int seccomp_mode(seccomp_t *s)
> +{
> + return 0;
> +}
> +
> #endif /* CONFIG_SECCOMP */
>
> #endif /* _LINUX_SECCOMP_H */
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
Attachment:
.config
Description: Binary data