History log of /arch/x86/kvm/i8254.c
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a647795efbedeedf8a1dc6deded26defa23562bd 14-Dec-2011 Jan Kiszka <jan.kiszka@siemens.com> KVM: x86: Consolidate PIT legacy test

Move the test for KVM_PIT_FLAGS_HPET_LEGACY into create_pit_timer
instead of replicating it on the caller site.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
0924ab2cfa98b1ece26c033d696651fd62896c69 14-Dec-2011 Jan Kiszka <jan.kiszka@siemens.com> KVM: x86: Prevent starting PIT timers in the absence of irqchip support

User space may create the PIT and forgets about setting up the irqchips.
In that case, firing PIT IRQs will crash the host:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000128
IP: [<ffffffffa10f6280>] kvm_set_irq+0x30/0x170 [kvm]
...
Call Trace:
[<ffffffffa11228c1>] pit_do_work+0x51/0xd0 [kvm]
[<ffffffff81071431>] process_one_work+0x111/0x4d0
[<ffffffff81071bb2>] worker_thread+0x152/0x340
[<ffffffff81075c8e>] kthread+0x7e/0x90
[<ffffffff815a4474>] kernel_thread_helper+0x4/0x10

Prevent this by checking the irqchip mode before starting a timer. We
can't deny creating the PIT if the irqchips aren't set up yet as
current user land expects this order to work.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
743eeb0b01d2fbf4154bf87bff1ebb6fb18aeb7a 27-Jul-2011 Sasha Levin <levinsasha928@gmail.com> KVM: Intelligent device lookup on I/O bus

Currently the method of dealing with an IO operation on a bus (PIO/MMIO)
is to call the read or write callback for each device registered
on the bus until we find a device which handles it.

Since the number of devices on a bus can be significant due to ioeventfds
and coalesced MMIO zones, this leads to a lot of overhead on each IO
operation.

Instead of registering devices, we now register ranges which points to
a device. Lookup is done using an efficient bsearch instead of a linear
search.

Performance test was conducted by comparing exit count per second with
200 ioeventfds created on one byte and the guest is trying to access a
different byte continuously (triggering usermode exits).
Before the patch the guest has achieved 259k exits per second, after the
patch the guest does 274k exits per second.

Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
9611c187774f0e20c258c23ced2599c44bd2fef4 06-Oct-2010 Nicolas Kaiser <nikai@nikai.net> KVM: fix typo in copyright notice

Fix typo in copyright notice.

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
23e7a7944f3779155e2f6bbc831b544eb925f387 27-Aug-2010 Jason Wang <jasowang@redhat.com> KVM: pit: Do not check pending pit timer in vcpu thread

Pit interrupt injection was done by workqueue, so no need to check
pending pit timer in vcpu thread which could lead unnecessary
unblocking of vcpu.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
6b5d7a9f6f7ff0e096829c1d82f70d5a6066b889 17-Aug-2010 Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> KVM: PIT: free irq source id in handling error path

Free irq source id if create pit workqueue fail

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
3185bf8c23149f32d7e7363b84539ea50b26ecb1 13-Aug-2010 Xiaotian Feng <dfeng@redhat.com> KVM: destroy workqueue on kvm_create_pit() failures

kernel needs to destroy workqueue if kvm_create_pit() fails, otherwise
after pit is freed, the workqueue is leaked.

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
aea924f606c309feead37ab5c43f410a08ff3826 10-Jul-2010 Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> KVM: PIT: stop vpit before freeing irq_routing

Fix:
general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
......
Call Trace:
[<ffffffffa0159bd1>] ? kvm_set_irq+0xdd/0x24b [kvm]
[<ffffffff8106ea8b>] ? trace_hardirqs_off_caller+0x1f/0x10e
[<ffffffff813ad17f>] ? sub_preempt_count+0xe/0xb6
[<ffffffff8106d273>] ? put_lock_stats+0xe/0x27
...
RIP [<ffffffffa0159c72>] kvm_set_irq+0x17e/0x24b [kvm]

This bug is triggered when guest is shutdown, is because we freed
irq_routing before pit thread stopped

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
673813e81d8468e80b6dd0fa839923eb9748dc49 07-Jul-2010 Jiri Slaby <jirislaby@gmail.com> KVM: fix lock imbalance in kvm_create_pit()

Stanse found that there is an omitted unlock in kvm_create_pit in one fail
path. Add proper unlock there.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Gleb Natapov <gleb@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Gregory Haskins <ghaskins@novell.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
33572ac0ad5ba5016da72e6654e607726568f9c0 16-Jun-2010 Chris Lalancette <clalance@redhat.com> KVM: x86: Introduce a workqueue to deliver PIT timer interrupts

We really want to "kvm_set_irq" during the hrtimer callback,
but that is risky because that is during interrupt context.
Instead, offload the work to a workqueue, which is a bit safer
and should provide most of the same functionality.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
221d059d15f1c8bd070a63fd45cd8d2598af5f99 23-May-2010 Avi Kivity <avi@redhat.com> KVM: Update Red Hat copyrights

Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
/arch/x86/kvm/i8254.c
fa8273e9549b3cee2947d1aebe5242e7a25eb3de 17-Feb-2010 Thomas Gleixner <tglx@linutronix.de> KVM: Convert i8254/i8259 locks to raw_spinlocks

The i8254/i8259 locks need to be real spinlocks on preempt-rt. Convert
them to raw_spinlock. No change for !RT kernels.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
d225f53b76f4287365efd381b9e3a732e6bad27e 08-Feb-2010 Wei Yongjun <yjwei@cn.fujitsu.com> KVM: PIT: unregister kvm irq notifier if fail to create pit

If fail to create pit, we should unregister kvm irq notifier
which register in kvm_create_pit().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
79fac95ecfa3969aab8119d37ccd7226165f933a 23-Dec-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: convert slots_lock to a mutex

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
e93f8a0f821e290ac5149830110a5f704db7a1fc 23-Dec-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: convert io_bus to SRCU

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
ee73f656a604d5aa9df86a97102e4e462dd79924 29-Jan-2010 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: control word is write-only

PIT control word (address 0x43) is write-only, reads are undefined.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
a78d9626f4f6fa7904bfdb071205080743125983 09-Dec-2009 Joe Perches <joe@perches.com> x86: i8254.c: Add pr_fmt(fmt)

- Add pr_fmt(fmt) "pit: " fmt
- Strip pit: prefixes from pr_debug

Signed-off-by: Joe Perches <joe@perches.com>
LKML-Reference: <bbd4de532f18bb7c11f64ba20d224c08291cb126.1260383912.git.joe@perches.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
/arch/x86/kvm/i8254.c
680b3648ba89c44ac8d0316f78a0d6e147b88809 24-Aug-2009 Gleb Natapov <gleb@redhat.com> KVM: Drop kvm->irq_lock lock from irq injection path

The only thing it protects now is interrupt injection into lapic and
this can work lockless. Even now with kvm->irq_lock in place access
to lapic is not entirely serialized since vcpu access doesn't take
kvm->irq_lock.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
ace1546487a0fe4634e3251067f8a32cb2cdc099 08-Oct-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: use proper hrtimer function to retrieve expiration time

hrtimer->base can be temporarily NULL due to racing hrtimer_start.
See switch_hrtimer_base/lock_hrtimer_base.

Use hrtimer_get_remaining which is robust against it.

CC: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
95fb4eb6981216c07ac01f598e61b273b6eff58c 29-Jul-2009 Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> KVM: remove superfluous NULL pointer check in kvm_inject_pit_timer_irqs()

This takes care of the following entries from Dan's list:

arch/x86/kvm/i8254.c +714 kvm_inject_pit_timer_irqs(6) warning: variable derefenced in initializer 'vcpu'
arch/x86/kvm/i8254.c +714 kvm_inject_pit_timer_irqs(6) warning: variable derefenced before check 'vcpu'

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Cc: Julia Lawall <julia@diku.dk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
84fde248fe42f130cdda39faaa8bb1224c6a13ff 16-Jul-2009 Gleb Natapov <gleb@redhat.com> KVM: PIT: Unregister ack notifier callback when freeing

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
/arch/x86/kvm/i8254.c
090b7aff27120cdae76a346a70db394844fea598 07-Jul-2009 Gregory Haskins <ghaskins@novell.com> KVM: make io_bus interface more robust

Today kvm_io_bus_regsiter_dev() returns void and will internally BUG_ON
if it fails. We want to create dynamic MMIO/PIO entries driven from
userspace later in the series, so we need to enhance the code to be more
robust with the following changes:

1) Add a return value to the registration function
2) Fix up all the callsites to check the return code, handle any
failures, and percolate the error up to the caller.
3) Add an unregister function that collapses holes in the array

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
e9f4275732add046fed4a548b8dbb98dbe500d2f 07-Jul-2009 Beth Kon <eak@us.ibm.com> KVM: PIT support for HPET legacy mode

When kvm is in hpet_legacy_mode, the hpet is providing the timer
interrupt and the pit should not be. So in legacy mode, the pit timer
is destroyed, but the *state* of the pit is maintained. So if kvm or
the guest tries to modify the state of the pit, this modification is
accepted, *except* that the timer isn't actually started. When we exit
hpet_legacy_mode, the current state of the pit (which is up to date
since we've been accepting modifications) is used to restart the pit
timer.

The saved_mode code in kvm_pit_load_count temporarily changes mode to
0xff in order to destroy the timer, but then restores the actual
value, again maintaining "current" state of the pit for possible later
reenablement.

[avi: add some reserved storage in the ioctl; make SET_PIT2 IOW]
[marcelo: fix memory corruption due to reserved storage]

Signed-off-by: Beth Kon <eak@us.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
bda9020e2463ec94db9f97e8615f3bae22069838 29-Jun-2009 Michael S. Tsirkin <mst@redhat.com> KVM: remove in_range from io devices

This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.

This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
6c474694530f377507f9aca438c17206e051e6e7 29-Jun-2009 Michael S. Tsirkin <mst@redhat.com> KVM: convert bus to slots_lock

Use slots_lock to protect device list on the bus. slots_lock is already
taken for read everywhere, so we only need to take it for write when
registering devices. This is in preparation to removing in_range and
kvm->lock around it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
894a9c5543abf6f88d36dc1b9f5d90f35db09cb3 23-Jun-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: x86: missing locking in PIT/IRQCHIP/SET_BSP_CPU ioctl paths

Correct missing locking in a few places in x86's vm_ioctl handling path.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
988a2cae6a3c0dea6df59808a935a9a697bfc28c 09-Jun-2009 Gleb Natapov <gleb@redhat.com> KVM: Use macro to iterate over vcpus.

[christian: remove unused variables on s390]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
1ed0ce000a6c20c36ec649e32fc24393ef418ed8 09-Jun-2009 Gleb Natapov <gleb@redhat.com> KVM: Use pointer to vcpu instead of vcpu_id in timer code.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
c5af89b68abb26eea5e745f33228f4d672f115e5 09-Jun-2009 Gleb Natapov <gleb@redhat.com> KVM: Introduce kvm_vcpu_is_bsp() function.

Use it instead of open code "vcpu_id zero is BSP" assumption.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
fa40a8214bb9bcae8d49c234c19d8b4a6c1f37ff 04-Jun-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: switch irq injection/acking data structures to irq_lock

Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:

CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]

[gleb: fix ia64 path]

Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
6b66ac1ae3328177305a2600eb85b7446f41fdc9 01-Jun-2009 Gregory Haskins <ghaskins@novell.com> KVM: do not register i8254 PIO regions until we are initialized

We currently publish the i8254 resources to the pio_bus before the devices
are fully initialized. Since we hold the pit_lock, its probably not
a real issue. But lets clean this up anyway.

Reported-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
d76685c4a074041ed168e0b04dd604c3df5dcaa5 01-Jun-2009 Gregory Haskins <ghaskins@novell.com> KVM: cleanup io_device code

We modernize the io_device code so that we use container_of() instead of
dev->private, and move the vtable to a separate ops structure
(theoretically allows better caching for multiple instances of the same
ops structure)

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
c5ff41ce66382d657a76bc06ba252d848826950f 14-May-2009 Jan Kiszka <jan.kiszka@web.de> KVM: Allow PIT emulation without speaker port

The in-kernel speaker emulation is only a dummy and also unneeded from
the performance point of view. Rather, it takes user space support to
generate sound output on the host, e.g. console beeps.

To allow this, introduce KVM_CREATE_PIT2 which controls in-kernel
speaker port emulation via a flag passed along the new IOCTL. It also
leaves room for future extensions of the PIT configuration interface.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
0ff77873b1318fc2d77a85e70690d3cd6cafbd41 03-Jul-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: fix kpit_elapsed division by zero

Fix division by zero triggered by latch count command on uninitialized
counter.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
ede2ccc51742059d356d419260460cbbf3e36273 08-Apr-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: fix count read and mode 0 handling

Commit 46ee278652f4cbd51013471b64c7897ba9bcd1b1 causes Solaris 10
to hang on boot.

Assuming that PIT counter reads should return 0 for an expired timer
is wrong: when it is active, the counter never stops (see comment on
__kpit_elapsed).

Also arm a one shot timer for mode 0.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
386eb6e8b3caface8a0514da70a47c05cabb5b96 10-Mar-2009 Hannes Eder <hannes@hanneseder.net> KVM: make 'lapic_timer_ops' and 'kpit_ops' static

Fix this sparse warnings:
arch/x86/kvm/lapic.c:916:22: warning: symbol 'lapic_timer_ops' was not declared. Should it be static?
arch/x86/kvm/i8254.c:268:22: warning: symbol 'kpit_ops' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
d3c7b77d1a6e7a0a27035a7ba723a3455317883e 23-Feb-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: unify part of generic timer handling

Hide the internals of vcpu awakening / injection from the in-kernel
emulated timers. This makes future changes in this logic easier and
decreases the distance to more generic timer handling.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
fd66842370e32f3bbe429677280a326c07e508c1 23-Feb-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: remove usage of count_load_time for channel 0

We can infer elapsed time from hrtimer_expires_remaining.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
5a05d54554f19a128306eca7f7f5ed31f7d7eeb9 23-Feb-2009 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: remove unused scheduled variable

Unused.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
4780c65904f0fc4e312ee2da9383eacbe04e61ea 04-Jan-2009 Avi Kivity <avi@redhat.com> KVM: Reset PIT irq injection logic when the PIT IRQ is unmasked

While the PIT is masked the guest cannot ack the irq, so the reinject logic
will never allow the interrupt to be injected.

Fix by resetting the reinjection counters on unmask.

Unbreaks Xen.

Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
269e05e48502f1cc06802e9fba90f5100dd6bb0d 05-Jan-2009 Avi Kivity <avi@redhat.com> KVM: Properly lock PIT creation

Otherwise, two threads can create a PIT in parallel and cause a memory leak.

Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
52d939a0bf44081bc9f69b4fbdc9e7f416df27c7 30-Dec-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: provide an option to disable interrupt reinjection

Certain clocks (such as TSC) in older 2.6 guests overaccount for lost
ticks, causing severe time drift. Interrupt reinjection magnifies the
problem.

Provide an option to disable it.

[avi: allow room for expansion in case we want to disable reinjection
of other timers]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
d2a8284e8fca9e2a938bee6cd074064d23864886 30-Dec-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: fix i8254 pending count read

count_load_time assignment is bogus: its supposed to contain what it
means, not the expiration time.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
cc6e462cd54e64858ea25816df87d033229efe56 20-Oct-2008 Jan Kiszka <jan.kiszka@siemens.com> KVM: x86: Optimize NMI watchdog delivery

As suggested by Avi, this patch introduces a counter of VCPUs that have
LVT0 set to NMI mode. Only if the counter > 0, we push the PIT ticks via
all LAPIC LVT0 lines to enable NMI watchdog support.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
8fdb2351d51b040146f10a624387bbd102d851c0 20-Oct-2008 Jan Kiszka <jan.kiszka@siemens.com> KVM: x86: Fix and refactor NMI watchdog emulation

This patch refactors the NMI watchdog delivery patch, consolidating
tests and providing a proper API for delivering watchdog events.

An included micro-optimization is to check only for apic_hw_enabled in
kvm_apic_local_deliver (the test for LVT mask is covering the
soft-disabled case already).

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
23930f9521c9c4d4aa96cdb9d1e1703f3782bb94 26-Sep-2008 Jan Kiszka <jan.kiszka@siemens.com> KVM: x86: Enable NMI Watchdog via in-kernel PIT source

LINT0 of the LAPIC can be used to route PIT events as NMI watchdog ticks
into the guest. This patch aligns the in-kernel irqchip emulation with
the user space irqchip with already supports this feature. The trick is
to route PIT interrupts to all LAPIC's LVT0 lines.

Rebased and slightly polished patch originally posted by Sheng Yang.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
e17d1dc0863767bab8fde4ba9be92c7f79e7fe50 11-Nov-2008 Avi Kivity <avi@redhat.com> KVM: Fix pit memory leak if unable to allocate irq source id

Reported-By: Daniel Marjamäki <danielm77@spray.se>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
5550af4df179e52753d3a43a788a113ad8cd95cd 15-Oct-2008 Sheng Yang <sheng@linux.intel.com> KVM: Fix guest shared interrupt with in-kernel irqchip

Every call of kvm_set_irq() should offer an irq_source_id, which is
allocated by kvm_request_irq_source_id(). Based on irq_source_id, we
identify the irq source and implement logical OR for shared level
interrupts.

The allocated irq_source_id can be freed by kvm_free_irq_source_id().

Currently, we support at most sizeof(unsigned long) different irq sources.

[Amit: - rebase to kvm.git HEAD
- move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file
- move kvm_request_irq_source_id to the update_irq ioctl]

[Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests]

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
/arch/x86/kvm/i8254.c
651dab4264e4ba0e563f5ff56f748127246e9065 17-Oct-2008 Arjan van de Ven <arjan@linux.intel.com> Merge commit 'linus/master' into merge-linus

Conflicts:

arch/x86/kvm/i8254.c
d76901750ab9f71091d33ef3d2b5909d8a9a4ad4 08-Sep-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: x86: do not execute halted vcpus

Offline or uninitialized vcpu's can be executed if requested to perform
userspace work.

Follow Avi's suggestion to handle halted vcpu's in the main loop,
simplifying kvm_emulate_halt(). Introduce a new vcpu->requests bit to
indicate events that promote state from halted to running.

Also standardize vcpu wake sites.

Signed-off-by: Marcelo Tosatti <mtosatti <at> redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
ee032c993edd34e0bdf64dab06a55d0e08a4eeb9 12-Aug-2008 Harvey Harrison <harvey.harrison@gmail.com> KVM: make irq ack notifier functions static

sparse says:

arch/x86/kvm/x86.c:107:32: warning: symbol 'kvm_find_assigned_dev' was not declared. Should it be static?
arch/x86/kvm/i8254.c:225:6: warning: symbol 'kvm_pit_ack_irq' was not declared. Should it be static?

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
29c8fa32c5d1e2d26d53ad9467b3a13130014cdf 18-Aug-2008 Amit Shah <amit.shah@qumranet.com> KVM: Use kvm_set_irq to inject interrupts

... instead of using the pic and ioapic variants

Signed-off-by: Amit Shah <amit.shah@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
dc7404cea34ef997dfe89ca94d16358e9d29c8d8 17-Aug-2008 Avi Kivity <avi@qumranet.com> KVM: Handle spurious acks for PIT interrupts

Spurious acks can be generated, for example if the PIC is being reset.
Handle those acks gracefully rather than flooding the log with warnings.

Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
3cf57fed216e2c1b6fdfeccb792650bab72a350a 26-Jul-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: fix injection logic and count

The PIT injection logic is problematic under the following cases:

1) If there is a higher priority vector to be delivered by the time
kvm_pit_timer_intr_post is invoked ps->inject_pending won't be set.
This opens the possibility for missing many PIT event injections (say if
guest executes hlt at this point).

2) ps->inject_pending is racy with more than two vcpus. Since there's no locking
around read/dec of pt->pending, two vcpu's can inject two interrupts for a single
pt->pending count.

Fix 1 by using an irq ack notifier: only reinject when the previous irq
has been acked. Fix 2 with appropriate locking around manipulation of
pending count and irq_ack by the injection / ack paths.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
beb20d52d03a51218827fb4a36a4b583debb03f9 01-Sep-2008 Arjan van de Ven <arjan@linux.intel.com> hrtimer: convert kvm to the new hrtimer apis

In order to be able to do range hrtimers we need to use accessor functions
to the "expire" member of the hrtimer struct.
This patch converts KVM to these accessors.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
/arch/x86/kvm/i8254.c
622395a9e63bf87a16faecf555ed02375cbae5b7 12-Jun-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: only abort guest entry if timer count goes from 0->1

Only abort guest entry if the timer count went from 0->1, since for 1->2
or larger the bit will either be set already or a timer irq will have
been injected.

Using atomic_inc_and_test() for it also introduces an SMP barrier
to the LAPIC version (thought it was unecessary because of timer
migration, but guest can be scheduled to a different pCPU between exit
and kvm_vcpu_block(), so there is the possibility for a race).

Noticed by Avi.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
92760499d01ef91518119908eb9b8798b6c9bd3f 30-May-2008 Laurent Vivier <Laurent.Vivier@bull.net> KVM: kvm_io_device: extend in_range() to manage len and write attribute

Modify member in_range() of structure kvm_io_device to pass length and the type
of the I/O (write or read).

This modification allows to use kvm_io_device with coalesced MMIO.

Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
f697554515b06e8d7264f316b25e6da943407142 02-May-2008 Aurelien Jarno <aurelien@aurel32.net> KVM: PIT: support mode 3

The in-kernel PIT emulation ignores pending timers if operating
under mode 3, which for example Hurd uses.

This mode should output a square wave, high for (N+1)/2 counts and low
for (N-1)/2 counts. As we only care about the resulting interrupts, the
period is N, and mode 3 is the same as mode 2 with regard to
interrupts.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
8b2cf73cc11cf29a21c51c453a3205f23d888915 27-Apr-2008 Harvey Harrison <harvey.harrison@gmail.com> KVM: add statics were possible, function definition in lapic.h

Noticed by sparse:
arch/x86/kvm/vmx.c:1583:6: warning: symbol 'vmx_disable_intercept_for_msr' was not declared. Should it be static?
arch/x86/kvm/x86.c:3406:5: warning: symbol 'kvm_task_switch_16' was not declared. Should it be static?
arch/x86/kvm/x86.c:3429:5: warning: symbol 'kvm_task_switch_32' was not declared. Should it be static?
arch/x86/kvm/mmu.c:1968:6: warning: symbol 'kvm_mmu_remove_one_alloc_mmu_page' was not declared. Should it be static?
arch/x86/kvm/mmu.c:2014:6: warning: symbol 'mmu_destroy_caches' was not declared. Should it be static?
arch/x86/kvm/lapic.c:862:5: warning: symbol 'kvm_lapic_get_base' was not declared. Should it be static?
arch/x86/kvm/i8254.c:94:5: warning: symbol 'pit_get_gate' was not declared. Should it be static?
arch/x86/kvm/i8254.c:196:5: warning: symbol '__pit_timer_fn' was not declared. Should it be static?
arch/x86/kvm/i8254.c:561:6: warning: symbol '__inject_pit_timer_intr' was not declared. Should it be static?

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
06e05645661211b9eaadaf6344c335d2e80f0ba2 06-Jun-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: close timer injection race window in __vcpu_run

If a timer fires after kvm_inject_pending_timer_irqs() but before
local_irq_disable() the code will enter guest mode and only inject such
timer interrupt the next time an unrelated event causes an exit.

It would be simpler if the timer->pending irq conversion could be done
with IRQ's disabled, so that the above problem cannot happen.

For now introduce a new vcpu requests bit to cancel guest entry.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
2f5997140f22f68f6390c49941150d3fa8a95cb7 27-May-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: migrate PIT timer

Migrate the PIT timer to the physical CPU which vcpu0 is scheduled on,
similarly to what is done for the LAPIC timers, otherwise PIT interrupts
will be delayed until an unrelated event causes an exit.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
eedaa4e2af681a266c084c410238855bdfbc2787 06-May-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: take inject_pending into account when emulating hlt

Otherwise hlt emulation fails if PIT is not injecting IRQ's.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
ece15babfa514e06118f62f4df2c757d6209f4f0 30-Apr-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: PIT: support mode 4

The in-kernel PIT emulation ignores pending timers if operating under
mode 4, which for example DragonFlyBSD uses (and Plan9 too, apparently).

Mode 4 seems to be similar to one-shot mode, other than the fact that it
starts counting after the next CLK pulse once programmed, while mode 1
starts counting immediately, so add a FIXME to enhance precision.

Fixes sourceforge bug 1952988.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Acked-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
6f6d6a1a6a1336431a6cba60ace9e97c3a496a19 01-May-2008 Roman Zippel <zippel@linux-m68k.org> rename div64_64 to div64_u64

Rename div64_64 to div64_u64 to make it consistent with the other divide
functions, so it clearly includes the type of the divide. Move its definition
to math64.h as currently no architecture overrides the generic implementation.
They can still override it of course, but the duplicated declarations are
avoided.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/arch/x86/kvm/i8254.c
a45352908b88d383bc40e1e4d1a6cc5bbcefc895 13-Apr-2008 Avi Kivity <avi@qumranet.com> KVM: Rename VCPU_MP_STATE_* to KVM_MP_STATE_*

We wish to export it to userspace, so move it into the kvm namespace.

Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
3d80840d96127401ba6aeadd813c3a15b84e70fe 11-Apr-2008 Marcelo Tosatti <mtosatti@redhat.com> KVM: hlt emulation should take in-kernel APIC/PIT timers into account

Timers that fire between guest hlt and vcpu_block's add_wait_queue() are
ignored, possibly resulting in hangs.

Also make sure that atomic_inc and waitqueue_active tests happen in the
specified order, otherwise the following race is open:

CPU0 CPU1
if (waitqueue_active(wq))
add_wait_queue()
if (!atomic_read(pit_timer->pending))
schedule()
atomic_inc(pit_timer->pending)

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
308b0f239e8d6754b8b903d279e5b5b987e257ac 13-Mar-2008 Sheng Yang <sheng.yang@intel.com> KVM: Add reset support for in kernel PIT

Separate the reset part and prepare for reset support.

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
e0f63cb9277b64850854aee301762beeeb463473 03-Mar-2008 Sheng Yang <sheng.yang@intel.com> KVM: Add save/restore supporting of in kernel PIT

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c
7837699fa6d7adf81f26ab73a5f6897ea1ab9d6a 27-Jan-2008 Sheng Yang <sheng.yang@intel.com> KVM: In kernel PIT model

The patch moves the PIT model from userspace to kernel, and increases
the timer accuracy greatly.

[marcelo: make last_injected_time per-guest]

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
/arch/x86/kvm/i8254.c