<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/virt/kvm/irq_comm.c, branch v3.7.4</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>KVM: Add resampling irqfds for level triggered interrupts</title>
<updated>2012-09-23T11:50:15+00:00</updated>
<author>
<name>Alex Williamson</name>
<email>alex.williamson@redhat.com</email>
</author>
<published>2012-09-21T17:58:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7a84428af7ca6a847f058c9ff244a18a2664fd1b'/>
<id>7a84428af7ca6a847f058c9ff244a18a2664fd1b</id>
<content type='text'>
To emulate level triggered interrupts, add a resample option to
KVM_IRQFD.  When specified, a new resamplefd is provided that notifies
the user when the irqchip has been resampled by the VM.  This may, for
instance, indicate an EOI.  Also in this mode, posting of an interrupt
through an irqfd only asserts the interrupt.  On resampling, the
interrupt is automatically de-asserted prior to user notification.
This enables level triggered interrupts to be posted and re-enabled
from vfio with no userspace intervention.

All resampling irqfds can make use of a single irq source ID, so we
reserve a new one for this interface.

Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To emulate level triggered interrupts, add a resample option to
KVM_IRQFD.  When specified, a new resamplefd is provided that notifies
the user when the irqchip has been resampled by the VM.  This may, for
instance, indicate an EOI.  Also in this mode, posting of an interrupt
through an irqfd only asserts the interrupt.  On resampling, the
interrupt is automatically de-asserted prior to user notification.
This enables level triggered interrupts to be posted and re-enabled
from vfio with no userspace intervention.

All resampling irqfds can make use of a single irq source ID, so we
reserve a new one for this interface.

Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: optimize apic interrupt delivery</title>
<updated>2012-09-20T12:05:26+00:00</updated>
<author>
<name>Gleb Natapov</name>
<email>gleb@redhat.com</email>
</author>
<published>2012-09-13T14:19:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1e08ec4a130e2745d96df169e67c58df98a07311'/>
<id>1e08ec4a130e2745d96df169e67c58df98a07311</id>
<content type='text'>
Most interrupt are delivered to only one vcpu. Use pre-build tables to
find interrupt destination instead of looping through all vcpus. In case
of logical mode loop only through vcpus in a logical cluster irq is sent
to.

Signed-off-by: Gleb Natapov &lt;gleb@redhat.com&gt;
Acked-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Most interrupt are delivered to only one vcpu. Use pre-build tables to
find interrupt destination instead of looping through all vcpus. In case
of logical mode loop only through vcpus in a logical cluster irq is sent
to.

Signed-off-by: Gleb Natapov &lt;gleb@redhat.com&gt;
Acked-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'queue' into next</title>
<updated>2012-07-26T08:54:21+00:00</updated>
<author>
<name>Avi Kivity</name>
<email>avi@redhat.com</email>
</author>
<published>2012-07-26T08:54:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e9bda6f6f902e6b55d9baceb5523468a048cbe56'/>
<id>e9bda6f6f902e6b55d9baceb5523468a048cbe56</id>
<content type='text'>
Merge patches queued during the run-up to the merge window.

* queue: (25 commits)
  KVM: Choose better candidate for directed yield
  KVM: Note down when cpu relax intercepted or pause loop exited
  KVM: Add config to support ple or cpu relax optimzation
  KVM: switch to symbolic name for irq_states size
  KVM: x86: Fix typos in pmu.c
  KVM: x86: Fix typos in lapic.c
  KVM: x86: Fix typos in cpuid.c
  KVM: x86: Fix typos in emulate.c
  KVM: x86: Fix typos in x86.c
  KVM: SVM: Fix typos
  KVM: VMX: Fix typos
  KVM: remove the unused parameter of gfn_to_pfn_memslot
  KVM: remove is_error_hpa
  KVM: make bad_pfn static to kvm_main.c
  KVM: using get_fault_pfn to get the fault pfn
  KVM: MMU: track the refcount when unmap the page
  KVM: x86: remove unnecessary mark_page_dirty
  KVM: MMU: Avoid handling same rmap_pde in kvm_handle_hva_range()
  KVM: MMU: Push trace_kvm_age_page() into kvm_age_rmapp()
  KVM: MMU: Add memslot parameter to hva handlers
  ...

Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge patches queued during the run-up to the merge window.

* queue: (25 commits)
  KVM: Choose better candidate for directed yield
  KVM: Note down when cpu relax intercepted or pause loop exited
  KVM: Add config to support ple or cpu relax optimzation
  KVM: switch to symbolic name for irq_states size
  KVM: x86: Fix typos in pmu.c
  KVM: x86: Fix typos in lapic.c
  KVM: x86: Fix typos in cpuid.c
  KVM: x86: Fix typos in emulate.c
  KVM: x86: Fix typos in x86.c
  KVM: SVM: Fix typos
  KVM: VMX: Fix typos
  KVM: remove the unused parameter of gfn_to_pfn_memslot
  KVM: remove is_error_hpa
  KVM: make bad_pfn static to kvm_main.c
  KVM: using get_fault_pfn to get the fault pfn
  KVM: MMU: track the refcount when unmap the page
  KVM: x86: remove unnecessary mark_page_dirty
  KVM: MMU: Avoid handling same rmap_pde in kvm_handle_hva_range()
  KVM: MMU: Push trace_kvm_age_page() into kvm_age_rmapp()
  KVM: MMU: Add memslot parameter to hva handlers
  ...

Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2012-07-24T19:01:20+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-07-24T19:01:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5fecc9d8f59e765c2a48379dd7c6f5cf88c7d75a'/>
<id>5fecc9d8f59e765c2a48379dd7c6f5cf88c7d75a</id>
<content type='text'>
Pull KVM updates from Avi Kivity:
 "Highlights include
  - full big real mode emulation on pre-Westmere Intel hosts (can be
    disabled with emulate_invalid_guest_state=0)
  - relatively small ppc and s390 updates
  - PCID/INVPCID support in guests
  - EOI avoidance; 3.6 guests should perform better on 3.6 hosts on
    interrupt intensive workloads)
  - Lockless write faults during live migration
  - EPT accessed/dirty bits support for new Intel processors"

Fix up conflicts in:
 - Documentation/virtual/kvm/api.txt:

   Stupid subchapter numbering, added next to each other.

 - arch/powerpc/kvm/booke_interrupts.S:

   PPC asm changes clashing with the KVM fixes

 - arch/s390/include/asm/sigp.h, arch/s390/kvm/sigp.c:

   Duplicated commits through the kvm tree and the s390 tree, with
   subsequent edits in the KVM tree.

* tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits)
  KVM: fix race with level interrupts
  x86, hyper: fix build with !CONFIG_KVM_GUEST
  Revert "apic: fix kvm build on UP without IOAPIC"
  KVM guest: switch to apic_set_eoi_write, apic_write
  apic: add apic_set_eoi_write for PV use
  KVM: VMX: Implement PCID/INVPCID for guests with EPT
  KVM: Add x86_hyper_kvm to complete detect_hypervisor_platform check
  KVM: PPC: Critical interrupt emulation support
  KVM: PPC: e500mc: Fix tlbilx emulation for 64-bit guests
  KVM: PPC64: booke: Set interrupt computation mode for 64-bit host
  KVM: PPC: bookehv: Add ESR flag to Data Storage Interrupt
  KVM: PPC: bookehv64: Add support for std/ld emulation.
  booke: Added crit/mc exception handler for e500v2
  booke/bookehv: Add host crit-watchdog exception support
  KVM: MMU: document mmu-lock and fast page fault
  KVM: MMU: fix kvm_mmu_pagetable_walk tracepoint
  KVM: MMU: trace fast page fault
  KVM: MMU: fast path of handling guest page fault
  KVM: MMU: introduce SPTE_MMU_WRITEABLE bit
  KVM: MMU: fold tlb flush judgement into mmu_spte_update
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull KVM updates from Avi Kivity:
 "Highlights include
  - full big real mode emulation on pre-Westmere Intel hosts (can be
    disabled with emulate_invalid_guest_state=0)
  - relatively small ppc and s390 updates
  - PCID/INVPCID support in guests
  - EOI avoidance; 3.6 guests should perform better on 3.6 hosts on
    interrupt intensive workloads)
  - Lockless write faults during live migration
  - EPT accessed/dirty bits support for new Intel processors"

Fix up conflicts in:
 - Documentation/virtual/kvm/api.txt:

   Stupid subchapter numbering, added next to each other.

 - arch/powerpc/kvm/booke_interrupts.S:

   PPC asm changes clashing with the KVM fixes

 - arch/s390/include/asm/sigp.h, arch/s390/kvm/sigp.c:

   Duplicated commits through the kvm tree and the s390 tree, with
   subsequent edits in the KVM tree.

* tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits)
  KVM: fix race with level interrupts
  x86, hyper: fix build with !CONFIG_KVM_GUEST
  Revert "apic: fix kvm build on UP without IOAPIC"
  KVM guest: switch to apic_set_eoi_write, apic_write
  apic: add apic_set_eoi_write for PV use
  KVM: VMX: Implement PCID/INVPCID for guests with EPT
  KVM: Add x86_hyper_kvm to complete detect_hypervisor_platform check
  KVM: PPC: Critical interrupt emulation support
  KVM: PPC: e500mc: Fix tlbilx emulation for 64-bit guests
  KVM: PPC64: booke: Set interrupt computation mode for 64-bit host
  KVM: PPC: bookehv: Add ESR flag to Data Storage Interrupt
  KVM: PPC: bookehv64: Add support for std/ld emulation.
  booke: Added crit/mc exception handler for e500v2
  booke/bookehv: Add host crit-watchdog exception support
  KVM: MMU: document mmu-lock and fast page fault
  KVM: MMU: fix kvm_mmu_pagetable_walk tracepoint
  KVM: MMU: trace fast page fault
  KVM: MMU: fast path of handling guest page fault
  KVM: MMU: introduce SPTE_MMU_WRITEABLE bit
  KVM: MMU: fold tlb flush judgement into mmu_spte_update
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: switch to symbolic name for irq_states size</title>
<updated>2012-07-20T19:12:16+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2012-07-19T10:55:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=93b6547e2219784b2df790353e083e0bdbebd2c2'/>
<id>93b6547e2219784b2df790353e083e0bdbebd2c2</id>
<content type='text'>
Use PIC_NUM_PINS instead of hard-coded 16 for pic pins.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use PIC_NUM_PINS instead of hard-coded 16 for pic pins.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: fix race with level interrupts</title>
<updated>2012-07-20T19:12:00+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2012-07-19T10:45:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1a577b72475d161b6677c05abe57301362023bb2'/>
<id>1a577b72475d161b6677c05abe57301362023bb2</id>
<content type='text'>
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 &lt;gleb@redhat.com&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;gleb@redhat.com&gt;
Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: Fix buffer overflow in kvm_set_irq()</title>
<updated>2012-06-05T13:39:58+00:00</updated>
<author>
<name>Avi Kivity</name>
<email>avi@redhat.com</email>
</author>
<published>2012-04-22T14:02:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f2ebd422f71cda9c791f76f85d2ca102ae34a1ed'/>
<id>f2ebd422f71cda9c791f76f85d2ca102ae34a1ed</id>
<content type='text'>
kvm_set_irq() has an internal buffer of three irq routing entries, allowing
connecting a GSI to three IRQ chips or on MSI.  However setup_routing_entry()
does not properly enforce this, allowing three irqchip routes followed by
an MSI route to overflow the buffer.

Fix by ensuring that an MSI entry is added to an empty list.

Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
kvm_set_irq() has an internal buffer of three irq routing entries, allowing
connecting a GSI to three IRQ chips or on MSI.  However setup_routing_entry()
does not properly enforce this, allowing three irqchip routes followed by
an MSI route to overflow the buffer.

Fix by ensuring that an MSI entry is added to an empty list.

Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: Introduce direct MSI message injection for in-kernel irqchips</title>
<updated>2012-04-24T12:59:47+00:00</updated>
<author>
<name>Jan Kiszka</name>
<email>jan.kiszka@siemens.com</email>
</author>
<published>2012-03-29T19:14:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=07975ad3b30579ca27d880491ad992326b930c63'/>
<id>07975ad3b30579ca27d880491ad992326b930c63</id>
<content type='text'>
Currently, MSI messages can only be injected to in-kernel irqchips by
defining a corresponding IRQ route for each message. This is not only
unhandy if the MSI messages are generated "on the fly" by user space,
IRQ routes are a limited resource that user space has to manage
carefully.

By providing a direct injection path, we can both avoid using up limited
resources and simplify the necessary steps for user land.

Signed-off-by: Jan Kiszka &lt;jan.kiszka@siemens.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, MSI messages can only be injected to in-kernel irqchips by
defining a corresponding IRQ route for each message. This is not only
unhandy if the MSI messages are generated "on the fly" by user space,
IRQ routes are a limited resource that user space has to manage
carefully.

By providing a direct injection path, we can both avoid using up limited
resources and simplify the necessary steps for user land.

Signed-off-by: Jan Kiszka &lt;jan.kiszka@siemens.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: fast-path msi injection with irqfd</title>
<updated>2011-01-12T09:29:38+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2010-11-18T17:09:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bd2b53b20fcd0d6c4c815b54e6d464e34429d3a4'/>
<id>bd2b53b20fcd0d6c4c815b54e6d464e34429d3a4</id>
<content type='text'>
Store irq routing table pointer in the irqfd object,
and use that to inject MSI directly without bouncing out to
a kernel thread.

While we touch this structure, rearrange irqfd fields to make fastpath
better packed for better cache utilization.

This also adds some comments about locking rules and rcu usage in code.

Some notes on the design:
- Use pointer into the rt instead of copying an entry,
  to make it possible to use rcu, thus side-stepping
  locking complexities.  We also save some memory this way.
- Old workqueue code is still used for level irqs.
  I don't think we DTRT with level anyway, however,
  it seems easier to keep the code around as
  it has been thought through and debugged, and fix level later than
  rip out and re-instate it later.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Acked-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
Acked-by: Gregory Haskins &lt;ghaskins@novell.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Store irq routing table pointer in the irqfd object,
and use that to inject MSI directly without bouncing out to
a kernel thread.

While we touch this structure, rearrange irqfd fields to make fastpath
better packed for better cache utilization.

This also adds some comments about locking rules and rcu usage in code.

Some notes on the design:
- Use pointer into the rt instead of copying an entry,
  to make it possible to use rcu, thus side-stepping
  locking complexities.  We also save some memory this way.
- Old workqueue code is still used for level irqs.
  I don't think we DTRT with level anyway, however,
  it seems easier to keep the code around as
  it has been thought through and debugged, and fix level later than
  rip out and re-instate it later.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Acked-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
Acked-by: Gregory Haskins &lt;ghaskins@novell.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: fix typo in copyright notice</title>
<updated>2010-10-24T08:53:14+00:00</updated>
<author>
<name>Nicolas Kaiser</name>
<email>nikai@nikai.net</email>
</author>
<published>2010-10-06T12:23:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9611c187774f0e20c258c23ced2599c44bd2fef4'/>
<id>9611c187774f0e20c258c23ced2599c44bd2fef4</id>
<content type='text'>
Fix typo in copyright notice.

Signed-off-by: Nicolas Kaiser &lt;nikai@nikai.net&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix typo in copyright notice.

Signed-off-by: Nicolas Kaiser &lt;nikai@nikai.net&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
