linux/Documentation
Glauber Costa afbcf7ab8d KVM: allow userspace to adjust kvmclock offset
When we migrate a kvm guest that uses pvclock between two hosts, we may
suffer a large skew. This is because there can be significant differences
between the monotonic clock of the hosts involved. When a new host with
a much larger monotonic time starts running the guest, the view of time
will be significantly impacted.

Situation is much worse when we do the opposite, and migrate to a host with
a smaller monotonic clock.

This proposed ioctl will allow userspace to inform us what is the monotonic
clock value in the source host, so we can keep the time skew short, and
more importantly, never goes backwards. Userspace may also need to trigger
the current data, since from the first migration onwards, it won't be
reflected by a simple call to clock_gettime() anymore.

[marcelo: future-proof abi with a flags field]
[jan: fix KVM_GET_CLOCK by clearing flags field instead of checking it]

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:19 +02:00
..
ABI Documentation: ABI: /sys/devices/system/cpu/cpu#/node 2009-10-30 14:59:53 -07:00
accounting Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
acpi
aoe
arm ARM: 5738/1: Correct TCM documentation 2009-10-01 16:26:16 +01:00
auxdisplay includecheck fix: Documentation, cfag12864b-example.c 2009-09-24 07:20:57 -07:00
blackfin
block
blockdev
cdrom
cgroups cgroups: update documentation of cgroups tasks and procs files 2009-10-08 07:36:39 -07:00
connector connector: Provide the sender's credentials to the callback 2009-10-02 10:54:01 -07:00
console
cpu-freq [CPUFREQ] update Doc for cpuinfo_cur_freq and scaling_cur_freq 2009-09-01 12:45:09 -04:00
cpuidle
cris
crypto async_tx: add support for asynchronous RAID6 recovery operations 2009-08-29 19:09:27 -07:00
development-process
device-mapper
DocBook Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-09-22 07:51:45 -07:00
driver-model
dvb V4L/DVB (12902): Documentation: synchronize documentation for Technisat cards 2009-09-19 00:14:32 -03:00
early-userspace
fault-injection
fb fbdev: Migrate mailing lists to vger 2009-11-30 13:46:04 -08:00
filesystems Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache 2009-11-30 13:33:48 -08:00
firmware_class
frv
hwmon hwmon: enhance the sysfs API for power meters 2009-10-29 07:39:30 -07:00
i2c i2c-piix4: Modify code name SB900 to Hudson-2 2009-11-07 13:10:46 +01:00
i2o
ia64 Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
ide
infiniband IB: Fix typo in udev rule documentation 2009-10-07 15:35:55 -07:00
input
ioctl drivers/char/uv_mmtimer.c: add memory mapped RTC driver for UV 2009-09-24 07:21:03 -07:00
isdn Documentation: expand isdn/INTERFACE.CAPI document 2009-10-06 22:20:51 -07:00
ja_JP
kbuild kbuild: introduce ld-option 2009-09-20 12:27:42 +02:00
kdump
ko_KR
kvm KVM: allow userspace to adjust kvmclock offset 2009-12-03 09:32:19 +02:00
laptops Merge branch 'thinkpad-2.6.32-part2' into release 2009-09-26 01:08:55 -04:00
lguest virtio: let header files include virtio_ids.h 2009-10-22 16:39:28 +10:30
m68k
make
mips
misc-devices max6875: Discard obsolete detect method 2009-10-04 22:53:41 +02:00
mn10300
mtd
namespaces
netlabel
networking pktgen: Fix multiqueue handling 2009-10-04 21:08:54 -07:00
parisc
PCI PCI: document PCIe fundamental reset interfaces 2009-09-09 13:29:38 -07:00
pcmcia Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
power Merge git://git.infradead.org/battery-2.6 2009-09-23 10:11:08 -07:00
powerpc Merge git://git.infradead.org/mtd-2.6 2009-09-23 10:07:49 -07:00
pps
prctl
RCU
s390 [S390] s390dbf: Add description for usage of "%s" in sprintf events 2009-09-11 10:29:53 +02:00
scheduler
scsi [SCSI] hptiop: Add RR44xx adapter support 2009-10-02 09:45:22 -05:00
serial
sh
sound ALSA: dummy - Fix descriptions of pcm_substreams parameter 2009-11-02 14:11:55 +01:00
sparc
spi spi: fix spelling of `automatically' in documentation 2009-09-23 07:39:44 -07:00
sysctl Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
telephony
thermal thermal: sysfs-api.txt - document passive attribute for thermal zones 2009-11-05 18:11:18 -05:00
timers
trace tracing: Fix comment typo and documentation example 2009-10-24 11:07:50 +02:00
uml
usb USB: Fix sysfs paths in documentation 2009-09-23 06:46:41 -07:00
video4linux Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
vm Merge branch 'hostprogs-wmissing-prototypes' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc 2009-11-17 09:14:49 -08:00
w1 ds2482: Discard obsolete detect method 2009-10-04 22:53:41 +02:00
watchdog Documentation/: fix warnings from -Wmissing-prototypes in HOSTCFLAGS 2009-09-23 07:39:28 -07:00
wimax
x86 USB: ehci-dbgp,documentation: Documentation updates for ehci-dbgp 2009-09-23 06:46:39 -07:00
zh_CN
00-INDEX
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
c2port.txt
cachetlb.txt
Changes
CodingStyle
cpu-hotplug.txt
cpu-load.txt
cputopology.txt Documentation: ABI: /sys/devices/system/cpu/cpu#/ topology files 2009-10-30 14:59:52 -07:00
credentials.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt ieee1394: update URLs in debugging-via-ohci1394.txt 2009-10-03 09:28:11 +02:00
dell_rbu.txt
devices.txt
DMA-API.txt
DMA-attributes.txt
DMA-ISA-LPC.txt
DMA-mapping.txt
dmaengine.txt
dontdiff sparc: Kill PROM console driver. 2009-09-15 17:04:38 -07:00
dynamic-debug-howto.txt
edac.txt
eisa.txt
email-clients.txt
feature-removal-schedule.txt inotify: deprecate the inotify kernel interface 2009-10-18 15:49:38 -04:00
flexible-arrays.txt Update flex_arrays.txt 2009-10-15 07:25:20 -06:00
futex-requeue-pi.txt
gcov.txt trivial: fix typo in CONFIG_DEBUG_FS in gcov doc 2009-09-21 15:14:56 +02:00
gpio.txt gpiolib: allow poll() on value 2009-09-23 07:39:48 -07:00
highuid.txt
HOWTO
hw_random.txt
ics932s401
initrd.txt
intel_txt.txt
Intel-IOMMU.txt intel-iommu: Kill DMAR_BROKEN_GFX_WA option. 2009-09-19 09:37:23 -07:00
io_ordering.txt
io-mapping.txt
IO-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt kernel-doc: allow multi-line declaration purpose descriptions 2009-09-18 09:48:52 -07:00
kernel-docs.txt
kernel-parameters.txt x86: earlyprintk: Fix regression to handle serial,ttySn as 1 arg 2009-10-01 10:34:16 +02:00
keys-request-key.txt
keys.txt KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] 2009-09-02 21:29:22 +10:00
kmemcheck.txt
kmemleak.txt kmemleak: add clear command support 2009-09-08 16:36:08 +01:00
kobject.txt
kprobes.txt
kref.txt kref: double kref_put() in my_data_handler() 2009-09-18 09:48:52 -07:00
ldm.txt
leds-class.txt
leds-lp3944.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
mca.txt
md.txt
memory-barriers.txt
memory-hotplug.txt
memory.txt Documentation/memory.txt: remove some very outdated recommendations 2009-09-22 07:17:26 -07:00
mono.txt
mutex-design.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt mm: fix NUMA accounting in numastat.txt 2009-09-22 07:17:39 -07:00
oops-tracing.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
rbtree.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt rtc: add boot_timesource sysfs attribute 2009-09-23 07:39:46 -07:00
SAK.txt
SecurityBugs
SELinux.txt
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
slow-work.txt SLOW_WORK: Move slow_work's proc file to debugfs 2009-12-01 08:20:31 -08:00
SM501.txt
Smack.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches docs: update patch size in SubmittingPatches 2009-10-01 16:11:12 -07:00
svga.txt
sysfs-rules.txt
sysrq.txt
tomoyo.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
vgaarbiter.txt PCI/VGA: add VGA arbitration documentation 2009-09-09 13:29:42 -07:00
video-output.txt
volatile-considered-harmful.txt
voyager.txt
zorro.txt