diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-02 12:26:43 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-02 12:26:43 -0700 |
commit | c6f21243ce1e8d81ad8361da4d2eaa5947b667c4 (patch) | |
tree | 5157ca1de2e7a5371575fff92ce23f0d09e3e7ea /arch/x86/kernel | |
parent | 9447dc43941cd1c006cae934984524b7c957b803 (diff) | |
parent | 37c975545ec63320789962bf307f000f08fabd48 (diff) |
Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 vdso changes from Peter Anvin:
"This is the revamp of the 32-bit vdso and the associated cleanups.
This adds timekeeping support to the 32-bit vdso that we already have
in the 64-bit vdso. Although 32-bit x86 is legacy, it is likely to
remain in the embedded space for a very long time to come.
This removes the traditional COMPAT_VDSO support; the configuration
variable is reused for simply removing the 32-bit vdso, which will
produce correct results but obviously suffer a performance penalty.
Only one beta version of glibc was affected, but that version was
unfortunately included in one OpenSUSE release.
This is not the end of the vdso cleanups. Stefani and Andy have
agreed to continue work for the next kernel cycle; in fact Andy has
already produced another set of cleanups that came too late for this
cycle.
An incidental, but arguably important, change is that this ensures
that unused space in the VVAR page is properly zeroed. It wasn't
before, and would contain whatever garbage was left in memory by BIOS
or the bootloader. Since the VVAR page is accessible to user space
this had the potential of information leaks"
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86, vdso: Fix the symbol versions on the 32-bit vDSO
x86, vdso, build: Don't rebuild 32-bit vdsos on every make
x86, vdso: Actually discard the .discard sections
x86, vdso: Fix size of get_unmapped_area()
x86, vdso: Finish removing VDSO32_PRELINK
x86, vdso: Move more vdso definitions into vdso.h
x86: Load the 32-bit vdso in place, just like the 64-bit vdsos
x86, vdso32: handle 32 bit vDSO larger one page
x86, vdso32: Disable stack protector, adjust optimizations
x86, vdso: Zero-pad the VVAR page
x86, vdso: Add 32 bit VDSO time support for 64 bit kernel
x86, vdso: Add 32 bit VDSO time support for 32 bit kernel
x86, vdso: Patch alternatives in the 32-bit VDSO
x86, vdso: Introduce VVAR marco for vdso32
x86, vdso: Cleanup __vdso_gettimeofday()
x86, vdso: Replace VVAR(vsyscall_gtod_data) by gtod macro
x86, vdso: __vdso_clock_gettime() cleanup
x86, vdso: Revamp vclock_gettime.c
mm: Add new func _install_special_mapping() to mmap.c
x86, vdso: Make vsyscall_gtod_data handling x86 generic
...
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/x86/kernel/hpet.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/tsc.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 8 | ||||
-rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 45 | ||||
-rw-r--r-- | arch/x86/kernel/vsyscall_gtod.c | 69 |
6 files changed, 75 insertions, 53 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index cb648c84b32..f4d96000d33 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -26,7 +26,7 @@ obj-$(CONFIG_IRQ_WORK) += irq_work.o obj-y += probe_roms.o obj-$(CONFIG_X86_32) += i386_ksyms_32.o obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o -obj-y += syscall_$(BITS).o +obj-y += syscall_$(BITS).o vsyscall_gtod.o obj-$(CONFIG_X86_64) += vsyscall_64.o obj-$(CONFIG_X86_64) += vsyscall_emu_64.o obj-$(CONFIG_SYSFS) += ksysfs.o diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index 014618dbaa7..93eed15a8fd 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -752,9 +752,7 @@ static struct clocksource clocksource_hpet = { .mask = HPET_MASK, .flags = CLOCK_SOURCE_IS_CONTINUOUS, .resume = hpet_resume_counter, -#ifdef CONFIG_X86_64 .archdata = { .vclock_mode = VCLOCK_HPET }, -#endif }; static int hpet_clocksource_register(void) diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 7a9296ab883..57e5ce126d5 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -984,9 +984,7 @@ static struct clocksource clocksource_tsc = { .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_MUST_VERIFY, -#ifdef CONFIG_X86_64 .archdata = { .vclock_mode = VCLOCK_TSC }, -#endif }; void mark_tsc_unstable(char *reason) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index da6b35a9826..49edf2dd361 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -147,7 +147,6 @@ SECTIONS _edata = .; } :data -#ifdef CONFIG_X86_64 . = ALIGN(PAGE_SIZE); __vvar_page = .; @@ -165,12 +164,15 @@ SECTIONS #undef __VVAR_KERNEL_LDS #undef EMIT_VVAR + /* + * Pad the rest of the page with zeros. Otherwise the loader + * can leave garbage here. + */ + . = __vvar_beginning_hack + PAGE_SIZE; } :data . = ALIGN(__vvar_page + PAGE_SIZE, PAGE_SIZE); -#endif /* CONFIG_X86_64 */ - /* Init code and data - will be freed after init */ . = ALIGN(PAGE_SIZE); .init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) { diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 1f96f9347ed..9ea287666c6 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -47,14 +47,12 @@ #include <asm/segment.h> #include <asm/desc.h> #include <asm/topology.h> -#include <asm/vgtod.h> #include <asm/traps.h> #define CREATE_TRACE_POINTS #include "vsyscall_trace.h" DEFINE_VVAR(int, vgetcpu_mode); -DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data); static enum { EMULATE, NATIVE, NONE } vsyscall_mode = EMULATE; @@ -77,48 +75,6 @@ static int __init vsyscall_setup(char *str) } early_param("vsyscall", vsyscall_setup); -void update_vsyscall_tz(void) -{ - vsyscall_gtod_data.sys_tz = sys_tz; -} - -void update_vsyscall(struct timekeeper *tk) -{ - struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data; - - write_seqcount_begin(&vdata->seq); - - /* copy vsyscall data */ - vdata->clock.vclock_mode = tk->clock->archdata.vclock_mode; - vdata->clock.cycle_last = tk->clock->cycle_last; - vdata->clock.mask = tk->clock->mask; - vdata->clock.mult = tk->mult; - vdata->clock.shift = tk->shift; - - vdata->wall_time_sec = tk->xtime_sec; - vdata->wall_time_snsec = tk->xtime_nsec; - - vdata->monotonic_time_sec = tk->xtime_sec - + tk->wall_to_monotonic.tv_sec; - vdata->monotonic_time_snsec = tk->xtime_nsec - + (tk->wall_to_monotonic.tv_nsec - << tk->shift); - while (vdata->monotonic_time_snsec >= - (((u64)NSEC_PER_SEC) << tk->shift)) { - vdata->monotonic_time_snsec -= - ((u64)NSEC_PER_SEC) << tk->shift; - vdata->monotonic_time_sec++; - } - - vdata->wall_time_coarse.tv_sec = tk->xtime_sec; - vdata->wall_time_coarse.tv_nsec = (long)(tk->xtime_nsec >> tk->shift); - - vdata->monotonic_time_coarse = timespec_add(vdata->wall_time_coarse, - tk->wall_to_monotonic); - - write_seqcount_end(&vdata->seq); -} - static void warn_bad_vsyscall(const char *level, struct pt_regs *regs, const char *message) { @@ -374,7 +330,6 @@ void __init map_vsyscall(void) { extern char __vsyscall_page; unsigned long physaddr_vsyscall = __pa_symbol(&__vsyscall_page); - extern char __vvar_page; unsigned long physaddr_vvar_page = __pa_symbol(&__vvar_page); __set_fixmap(VSYSCALL_FIRST_PAGE, physaddr_vsyscall, diff --git a/arch/x86/kernel/vsyscall_gtod.c b/arch/x86/kernel/vsyscall_gtod.c new file mode 100644 index 00000000000..f9c6e56e14b --- /dev/null +++ b/arch/x86/kernel/vsyscall_gtod.c @@ -0,0 +1,69 @@ +/* + * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE + * Copyright 2003 Andi Kleen, SuSE Labs. + * + * Modified for x86 32 bit architecture by + * Stefani Seibold <stefani@seibold.net> + * sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany + * + * Thanks to hpa@transmeta.com 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. + * + */ + +#include <linux/timekeeper_internal.h> +#include <asm/vgtod.h> +#include <asm/vvar.h> + +DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data); + +void update_vsyscall_tz(void) +{ + vsyscall_gtod_data.tz_minuteswest = sys_tz.tz_minuteswest; + vsyscall_gtod_data.tz_dsttime = sys_tz.tz_dsttime; +} + +void update_vsyscall(struct timekeeper *tk) +{ + struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data; + + gtod_write_begin(vdata); + + /* copy vsyscall data */ + vdata->vclock_mode = tk->clock->archdata.vclock_mode; + vdata->cycle_last = tk->clock->cycle_last; + vdata->mask = tk->clock->mask; + vdata->mult = tk->mult; + vdata->shift = tk->shift; + + vdata->wall_time_sec = tk->xtime_sec; + vdata->wall_time_snsec = tk->xtime_nsec; + + vdata->monotonic_time_sec = tk->xtime_sec + + tk->wall_to_monotonic.tv_sec; + vdata->monotonic_time_snsec = tk->xtime_nsec + + (tk->wall_to_monotonic.tv_nsec + << tk->shift); + while (vdata->monotonic_time_snsec >= + (((u64)NSEC_PER_SEC) << tk->shift)) { + vdata->monotonic_time_snsec -= + ((u64)NSEC_PER_SEC) << tk->shift; + vdata->monotonic_time_sec++; + } + + vdata->wall_time_coarse_sec = tk->xtime_sec; + vdata->wall_time_coarse_nsec = (long)(tk->xtime_nsec >> tk->shift); + + vdata->monotonic_time_coarse_sec = + vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec; + vdata->monotonic_time_coarse_nsec = + vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec; + + while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) { + vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC; + vdata->monotonic_time_coarse_sec++; + } + + gtod_write_end(vdata); +} |