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2012-12-13KVM: inject ExtINT interrupt before APIC interruptsGleb Natapov
According to Intel SDM Volume 3 Section 10.8.1 "Interrupt Handling with the Pentium 4 and Intel Xeon Processors" and Section 10.8.2 "Interrupt Handling with the P6 Family and Pentium Processors" ExtINT interrupts are sent directly to the processor core for handling. Currently KVM checks APIC before it considers ExtINT interrupts for injection which is backwards from the spec. Make code behave according to the SDM. Signed-off-by: Gleb Natapov <gleb@redhat.com> Acked-by: "Zhang, Yang Z" <yang.z.zhang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-09-04KVM: cleanup pic resetGleb Natapov
kvm_pic_reset() is not used anywhere. Move reset logic from pic_ioport_write() there. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-14KVM: x86: drop parameter validation in ioapic/picMichael S. Tsirkin
We validate irq pin number when routing is setup, so code handling illegal irq # in pic and ioapic on each injection is never called. Drop it, replace with BUG_ON to catch out of bounds access bugs. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-07-26KVM: PIC: call ack notifiers for irqs that are dropped form irrGleb Natapov
After commit 242ec97c358256 PIT interrupts are no longer delivered after PIC reset. It happens because PIT injects interrupt only if previous one was acked, but since on PIC reset it is dropped from irr it will never be delivered and hence acknowledged. Fix that by calling ack notifier on PIC reset. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-20KVM: fix race with level interruptsMichael S. Tsirkin
When more than 1 source id is in use for the same GSI, we have the following race related to handling irq_states race: CPU 0 clears bit 0. CPU 0 read irq_state as 0. CPU 1 sets level to 1. CPU 1 calls kvm_ioapic_set_irq(1). CPU 0 calls kvm_ioapic_set_irq(0). Now ioapic thinks the level is 0 but irq_state is not 0. Fix by performing all irq_states bitmap handling under pic/ioapic lock. This also removes the need for atomics with irq_states handling. Reported-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-03-05KVM: x86: reset edge sense circuit of i8259 on initGleb Natapov
The spec says that during initialization "The edge sense circuit is reset which means that following initialization an interrupt request (IR) input must make a low-to-high transition to generate an interrupt", but currently if edge triggered interrupt is in IRR it is delivered after i8259 initialization. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27KVM: drop bsp_vcpu pointer from kvm structGleb Natapov
Drop bsp_vcpu pointer from kvm struct since its only use is incorrect anyway. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-09-25KVM: Clean up and extend rate-limited outputJan Kiszka
The use of printk_ratelimit is discouraged, replace it with pr*_ratelimited or __ratelimit. While at it, convert remaining guest-triggerable printks to rate-limited variants. 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>
2011-03-17KVM: remove isr_ack logic from PICGleb Natapov
isr_ack logic was added by e48258009d to avoid unnecessary IPIs. Back then it made sense, but now the code checks that vcpu is ready to accept interrupt before sending IPI, so this logic is no longer needed. The patch removes it. Fixes a regression with Debian/Hurd. Signed-off-by: Gleb Natapov <gleb@redhat.com> Reported-and-tested-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-02KVM: i8259: initialize isr_ackAvi Kivity
isr_ack is never initialized. So, until the first PIC reset, interrupts may fail to be injected. This can cause Windows XP to fail to boot, as reported in the fallout from the fix to https://bugzilla.kernel.org/show_bug.cgi?id=21962. Reported-and-tested-by: Nicolas Prochazka <prochazka.nicolas@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: Convert PIC lock from raw spinlock to ordinary spinlockAvi Kivity
The PIC code used to be called from preempt_disable() context, which wasn't very good for PREEMPT_RT. That is no longer the case, so move back from raw_spinlock_t to spinlock_t. Signed-off-by: Avi Kivity <avi@redhat.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24KVM: Check for pending events before attempting injectionAvi Kivity
Instead of blindly attempting to inject an event before each guest entry, check for a possible event first in vcpu->requests. Sites that can trigger event injection are modified to set KVM_REQ_EVENT: - interrupt, nmi window opening - ppr updates - i8259 output changes - local apic irr changes - rflags updates - gif flag set - event set on exit This improves non-injecting entry performance, and sets the stage for non-atomic injection. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24KVM: i8259: Make ICW1 conform to specAvi Kivity
ICW is not a full reset, instead it resets a limited number of registers in the PIC. Change ICW1 emulation to only reset those registers. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-09-08KVM: fix i8259 oops when no vcpus are onlineAvi Kivity
If there are no vcpus, found will be NULL. Check before doing anything with it. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-02KVM: x86: Call mask notifiers from picGleb Natapov
If pit delivers interrupt while pic is masking it OS will never do EOI and ack notifier will not be called so when pit will be unmasked no pit interrupts will be delivered any more. Calling mask notifiers solves this issue. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01KVM: Search the LAPIC's for one that will accept a PIC interruptChris Lalancette
Older versions of 32-bit linux have a "Checking 'hlt' instruction" test where they repeatedly call the 'hlt' instruction, and then expect a timer interrupt to kick the CPU out of halt. This happens before any LAPIC or IOAPIC setup happens, which means that all of the APIC's are in virtual wire mode at this point. Unfortunately, the current implementation of virtual wire mode is hardcoded to only kick the BSP, so if a crash+kexec occurs on a different vcpu, it will never get kicked. This patch makes pic_unlock() do the equivalent of kvm_irq_delivery_to_apic() for the IOAPIC code. That is, it runs through all of the vcpus looking for one that is in virtual wire mode. In the normal case where LAPICs and IOAPICs are configured, this won't be used at all. In the bootstrap phase of a modern OS, before the LAPICs and IOAPICs are configured, this will have exactly the same behavior as today; VCPU0 is always looked at first, so it will always get out of the loop after the first iteration. This will only go through the loop more than once during a kexec/kdump, in which case it will only do it a few times until the kexec'ed kernel programs the LAPIC and IOAPIC. Signed-off-by: Chris Lalancette <clalance@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: i8259: simplify pic_irq_request() calling sequenceAvi Kivity
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: i8259: reduce excessive abstraction for pic_irq_request()Avi Kivity
Part of the i8259 code pretends it isn't part of kvm, but we know better. Reduce excessive abstraction, eliminating callbacks and void pointers. Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01KVM: Update Red Hat copyrightsAvi Kivity
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25KVM: x86: Kick VCPU outside PIC lock againJan Kiszka
This restores the deferred VCPU kicking before 956f97cf. We need this over -rt as wake_up* requires non-atomic context in this configuration. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> 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: cleanup the failure path of KVM_CREATE_IRQCHIP ioctrlWei Yongjun
If we fail to init ioapic device or the fail to setup the default irq routing, the device register by kvm_create_pic() and kvm_ioapic_init() remain unregister. This patch fixed to do this. Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.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>
2009-12-03KVM: Move IO APIC to its own lockGleb Natapov
The allows removal of irq_lock from the injection path. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03KVM: Call pic_clear_isr() on pic reset to reuse logic thereGleb Natapov
Also move call of ack notifiers after pic state change. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Replace pic_lock()/pic_unlock() with direct call to spinlock functionsGleb Natapov
They are not doing anything else now. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Call ack notifiers from PIC when guest OS acks an IRQ.Gleb Natapov
Currently they are called when irq vector is been delivered. Calling ack notifiers at this point is wrong. Device assignment ack notifier enables host interrupts, but guest not yet had a chance to clear interrupt condition in a device. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Call kvm_vcpu_kick() inside pic spinlockGleb Natapov
d5ecfdd25 moved it out because back than it was impossible to call it inside spinlock. This restriction no longer exists. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@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: Add trace points in irqchip codeGleb Natapov
Add tracepoint in msi/ioapic/pic set_irq() functions, in IPI sending and in the point where IRQ is placed into apic's IRR. Signed-off-by: Gleb Natapov <gleb@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: 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: Grab pic lock in kvm_pic_clear_isr_ackMarcelo Tosatti
isr_ack is protected by kvm_pic->lock. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> 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>
2009-03-24KVM: fix sparse warnings: context imbalanceHannes Eder
Impact: Attribute function with __acquires(...) resp. __releases(...). Fix this sparse warnings: arch/x86/kvm/i8259.c:34:13: warning: context imbalance in 'pic_lock' - wrong count at exit arch/x86/kvm/i8259.c:39:13: warning: context imbalance in 'pic_unlock' - unexpected unlock Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: Report IRQ injection status to userspace.Gleb Natapov
IRQ injection status is either -1 (if there was no CPU found that should except the interrupt because IRQ was masked or ioapic was misconfigured or ...) or >= 0 in that case the number indicates to how many CPUs interrupt was injected. If the value is 0 it means that the interrupt was coalesced and probably should be reinjected. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24KVM: make irq ack notifications aware of routing tableMarcelo Tosatti
IRQ ack notifications assume an identity mapping between pin->gsi, which might not be the case with, for example, HPET. Translate before acking. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Acked-by: Gleb Natapov <gleb@redhat.com>
2008-12-31KVM: Add locking to virtual i8259 interrupt controllerAvi Kivity
While most accesses to the i8259 are with the kvm mutex taken, the call to kvm_pic_read_irq() is not. We can't easily take the kvm mutex there since the function is called with interrupts disabled. Fix by adding a spinlock to the virtual interrupt controller. Since we can't send an IPI under the spinlock (we also take the same spinlock in an irq disabled context), we defer the IPI until the spinlock is released. Similarly, we defer irq ack notifications until after spinlock release to avoid lock recursion. Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15KVM: PIC: enhance IPI avoidanceMarcelo Tosatti
The PIC code makes little effort to avoid kvm_vcpu_kick(), resulting in unnecessary guest exits in some conditions. For example, if the timer interrupt is routed through the IOAPIC, IRR for IRQ 0 will get set but not cleared, since the APIC is handling the acks. This means that everytime an interrupt < 16 is triggered, the priority logic will find IRQ0 pending and send an IPI to vcpu0 (in case IRQ0 is not masked, which is Linux's case). Introduce a new variable isr_ack to represent the IRQ's for which the guest has been signalled / cleared the ISR. Use it to avoid more than one IPI per trigger-ack cycle, in addition to the avoidance when ISR is set in get_priority(). Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15KVM: fix i8259 reset irq ackingMarcelo Tosatti
The irq ack during pic reset has three problems: - Ignores slave/master PIC, using gsi 0-8 for both. - Generates an ACK even if the APIC is in control. - Depends upon IMR being clear, which is broken if the irq was masked at the time it was generated. The last one causes the BIOS to hang after the first reboot of Windows installation, since PIT interrupts stop. [avi: fix check whether pic interrupts are seen by cpu] Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15KVM: irq ack notificationMarcelo Tosatti
Based on a patch from: Ben-Ami Yassour <benami@il.ibm.com> which was based on a patch from: Amit Shah <amit.shah@qumranet.com> Notify IRQ acking on PIC/APIC emulation. The previous patch missed two things: - Edge triggered interrupts on IOAPIC - PIC reset with IRR/ISR set should be equivalent to ack (LAPIC probably needs something similar). Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> CC: Amit Shah <amit.shah@qumranet.com> CC: Ben-Ami Yassour <benami@il.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15KVM: Consolidate PIC isr clearing into a functionAvi Kivity
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: check injected pic irq within valid pic irqsBen-Ami Yassour
Check that an injected pic irq is between 0 and 15. Signed-off-by: Ben-Ami Yassour <benami@il.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20KVM: kvm_io_device: extend in_range() to manage len and write attributeLaurent Vivier
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>
2008-01-30KVM: Move arch dependent files to new directory arch/x86/kvm/Avi Kivity
This paves the way for multiple architecture support. Note that while ioapic.c could potentially be shared with ia64, it is also moved. Signed-off-by: Avi Kivity <avi@qumranet.com>