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2013-04-15KVM: Let ioapic know the irq line statusYang Zhang
Userspace may deliver RTC interrupt without query the status. So we want to track RTC EOI for this case. Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-12-18kvm: fix i8254 counter 0 wraparoundNickolai Zeldovich
The kvm i8254 emulation for counter 0 (but not for counters 1 and 2) has at least two bugs in mode 0: 1. The OUT bit, computed by pit_get_out(), is never set high. 2. The counter value, computed by pit_get_count(), wraps back around to the initial counter value, rather than wrapping back to 0xFFFF (which is the behavior described in the comment in __kpit_elapsed, the behavior implemented by qemu, and the behavior observed on AMD hardware). The bug stems from __kpit_elapsed computing the elapsed time mod the initial counter value (stored as nanoseconds in ps->period). This is both unnecessary (none of the callers of kpit_elapsed expect the value to be at most the initial counter value) and incorrect (it causes pit_get_count to appear to wrap around to the initial counter value rather than 0xFFFF). Removing this mod from __kpit_elapsed fixes both of the above bugs. Signed-off-by: Nickolai Zeldovich <nickolai@csail.mit.edu> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2012-08-01KVM: fold kvm_pit_timer into kvm_kpit_stateAvi Kivity
One structure nests inside the other, providing no value at all. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01KVM: Simplify kvm_pit_timerAvi Kivity
'timer_mode_mask' is unused 'tscdeadline' is unused 't_ops' only adds needless indirection 'vcpu' is unused Remove. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01KVM: Remove internal timer abstractionAvi Kivity
kvm_timer_fn(), the sole inhabitant of timer.c, is only used by lapic.c. Move it there to make it easier to hack on it. struct kvm_timer is a thin wrapper around hrtimer, and only adds obfuscation. Move near its two users (with different names) to prepare for simplification. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-27KVM: x86: Run PIT work in own kthreadJan Kiszka
We can't run PIT IRQ injection work in the interrupt context of the host timer. This would allow the user to influence the handler complexity by asking for a broadcast to a large number of VCPUs. Therefore, this work was pushed into workqueue context in 9d244caf2e. However, this prevents prioritizing the PIT injection over other task as workqueues share kernel threads. This replaces the workqueue with a kthread worker and gives that thread a name in the format "kvm-pit/<owner-process-pid>". That allows to identify and adjust the kthread priority according to the VM process parameters. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-12-27KVM: x86: Consolidate PIT legacy testJan Kiszka
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>
2011-12-25KVM: x86: Prevent starting PIT timers in the absence of irqchip supportJan Kiszka
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>
2011-09-25KVM: Intelligent device lookup on I/O busSasha Levin
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>
2010-10-24KVM: fix typo in copyright noticeNicolas Kaiser
Fix typo in copyright notice. Signed-off-by: Nicolas Kaiser <nikai@nikai.net> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24KVM: pit: Do not check pending pit timer in vcpu threadJason Wang
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>
2010-08-17KVM: PIT: free irq source id in handling error pathXiao Guangrong
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>
2010-08-15KVM: destroy workqueue on kvm_create_pit() failuresXiaotian Feng
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>
2010-08-02KVM: PIT: stop vpit before freeing irq_routingXiao Guangrong
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>
2010-08-02KVM: fix lock imbalance in kvm_create_pit()Jiri Slaby
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>
2010-08-01KVM: x86: Introduce a workqueue to deliver PIT timer interruptsChris Lalancette
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>
2010-08-01KVM: Update Red Hat copyrightsAvi Kivity
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
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>
2010-03-01KVM: Convert i8254/i8259 locks to raw_spinlocksThomas Gleixner
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>
2010-03-01KVM: PIT: unregister kvm irq notifier if fail to create pitWei Yongjun
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>
2010-03-01KVM: convert slots_lock to a mutexMarcelo Tosatti
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01KVM: convert io_bus to SRCUMarcelo Tosatti
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-02-09KVM: PIT: control word is write-onlyMarcelo Tosatti
PIT control word (address 0x43) is write-only, reads are undefined. Cc: stable@kernel.org Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-10x86: i8254.c: Add pr_fmt(fmt)Joe Perches
- 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>
2009-12-03KVM: Drop kvm->irq_lock lock from irq injection pathGleb Natapov
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>
2009-10-16KVM: use proper hrtimer function to retrieve expiration timeMarcelo Tosatti
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>
2009-09-10KVM: remove superfluous NULL pointer check in kvm_inject_pit_timer_irqs()Bartlomiej Zolnierkiewicz
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>
2009-09-10KVM: PIT: Unregister ack notifier callback when freeingGleb Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10KVM: make io_bus interface more robustGregory Haskins
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>
2009-09-10KVM: PIT support for HPET legacy modeBeth Kon
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>
2009-09-10KVM: remove in_range from io devicesMichael S. Tsirkin
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>
2009-09-10KVM: convert bus to slots_lockMichael S. Tsirkin
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>
2009-09-10KVM: x86: missing locking in PIT/IRQCHIP/SET_BSP_CPU ioctl pathsMarcelo Tosatti
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>
2009-09-10KVM: Use macro to iterate over vcpus.Gleb Natapov
[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>
2009-09-10KVM: Use pointer to vcpu instead of vcpu_id in timer code.Gleb Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Introduce kvm_vcpu_is_bsp() function.Gleb Natapov
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>
2009-09-10KVM: switch irq injection/acking data structures to irq_lockMarcelo Tosatti
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>
2009-09-10KVM: do not register i8254 PIO regions until we are initializedGregory Haskins
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>
2009-09-10KVM: cleanup io_device codeGregory Haskins
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>
2009-09-10KVM: Allow PIT emulation without speaker portJan Kiszka
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>
2009-08-05KVM: PIT: fix kpit_elapsed division by zeroMarcelo Tosatti
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>
2009-06-10KVM: PIT: fix count read and mode 0 handlingMarcelo Tosatti
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>
2009-06-10KVM: make 'lapic_timer_ops' and 'kpit_ops' staticHannes Eder
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>
2009-06-10KVM: unify part of generic timer handlingMarcelo Tosatti
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>
2009-06-10KVM: PIT: remove usage of count_load_time for channel 0Marcelo Tosatti
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>
2009-06-10KVM: PIT: remove unused scheduled variableMarcelo Tosatti
Unused. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: Reset PIT irq injection logic when the PIT IRQ is unmaskedAvi Kivity
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>
2009-03-24KVM: Properly lock PIT creationAvi Kivity
Otherwise, two threads can create a PIT in parallel and cause a memory leak. Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: PIT: provide an option to disable interrupt reinjectionMarcelo Tosatti
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>
2009-02-15KVM: PIT: fix i8254 pending count readMarcelo Tosatti
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>