Commit Graph

189 Commits

Author SHA1 Message Date
Rusty Russell 498468961e KVM: Extract core of kvm_flush_remote_tlbs/kvm_reload_remote_mmus
Avi said:
> Wow, code duplication from Rusty. Things must be bad.

Something about glass houses comes to mind.  But instead, a patch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:45 +02:00
Christian Borntraeger 3d3aab1b97 KVM: set owner of cpu and vm file operations
There is a race between a "close of the file descriptors" and module
unload in the kvm module.

You can easily trigger this problem by applying this debug patch:
>--- kvm.orig/virt/kvm/kvm_main.c
>+++ kvm/virt/kvm/kvm_main.c
>@@ -648,10 +648,14 @@ void kvm_free_physmem(struct kvm *kvm)
>                kvm_free_physmem_slot(&kvm->memslots[i], NULL);
> }
>
>+#include <linux/delay.h>
> static void kvm_destroy_vm(struct kvm *kvm)
> {
>        struct mm_struct *mm = kvm->mm;
>
>+       printk("off1\n");
>+       msleep(5000);
>+       printk("off2\n");
>        spin_lock(&kvm_lock);
>        list_del(&kvm->vm_list);
>        spin_unlock(&kvm_lock);

and killing the userspace, followed by an rmmod.

The problem is that kvm_destroy_vm can run while the module count
is 0. That means, you can remove the module while kvm_destroy_vm
is running. But kvm_destroy_vm is part of the module text. This
causes a kerneloops. The race exists without the msleep but is much
harder to trigger.

This patch requires the fix for anon_inodes (anon_inodes: use fops->owner
for module refcount).
With this patch, we can set the owner of all anonymous KVM inodes file
operations. The VFS will then control the KVM module refcount as long as there
is an open file. kvm_destroy_vm will be called by the release function of the
last closed file - before the VFS drops the module refcount.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:45 +02:00
Glauber Costa 6f89724829 KVM: Really remove a slot when a user ask us so
Right now, KVM does not remove a slot when we do a
register ioctl for size 0 (would be the expected behaviour).

Instead, we only mark it as empty, but keep all bitmaps
and allocated data structures present. It completely
nullifies our chances of reusing that same slot again
for mapping a different piece of memory.

In this patch, we destroy rmaps, and vfree() the
pointers that used to hold the dirty bitmap, rmap
and lpage_info structures.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:41 +02:00
Mark McLoughlin 4a643be8c9 KVM: split out kvm_free_assigned_irq()
Split out the logic corresponding to undoing assign_irq() and
clean it up a bit.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:07 +02:00
Mark McLoughlin 61552367b2 KVM: add KVM_USERSPACE_IRQ_SOURCE_ID assertions
Make sure kvm_request_irq_source_id() never returns
KVM_USERSPACE_IRQ_SOURCE_ID.

Likewise, check that kvm_free_irq_source_id() never accepts
KVM_USERSPACE_IRQ_SOURCE_ID.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:07 +02:00
Mark McLoughlin f29b2673d3 KVM: don't free an unallocated irq source id
Set assigned_dev->irq_source_id to -1 so that we can avoid freeing
a source ID which we never allocated.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Mark McLoughlin fdd897e6b5 KVM: make kvm_unregister_irq_ack_notifier() safe
We never pass a NULL notifier pointer here, but we may well
pass a notifier struct which hasn't previously been
registered.

Guard against this by using hlist_del_init() which will
not do anything if the node hasn't been added to the list
and, when removing the node, will ensure that a subsequent
call to hlist_del_init() will be fine too.

Fixes an oops seen when an assigned device is freed before
and IRQ is assigned to it.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Mark McLoughlin 844c7a9ff4 KVM: remove the IRQ ACK notifier assertions
We will obviously never pass a NULL struct kvm_irq_ack_notifier* to
this functions. They are always embedded in the assigned device
structure, so the assertion add nothing.

The irqchip_in_kernel() assertion is very out of place - clearly
this little abstraction needs to know nothing about the upper
layer details.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Hannes Eder e8ba5d311d KVM: fix sparse warning
Impact: make global function static

  virt/kvm/kvm_main.c:85:6: warning: symbol 'kvm_rebooting' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:05 +02:00
Wu Fengguang b82091824e KVM: Prevent trace call into unloaded module text
Add marker_synchronize_unregister() before module unloading.
This prevents possible trace calls into unloaded module text.

Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:04 +02:00
Sheng Yang 5319c66252 KVM: MSI to INTx translate
Now we use MSI as default one, and translate MSI to INTx when guest need
INTx rather than MSI. For legacy device, we provide support for non-sharing
host IRQ.

Provide a parameter msi2intx for this method. The value is true by default in
x86 architecture.

We can't guarantee this mode can work on every device, but for most of us
tested, it works. If your device encounter some trouble with this mode, you can
try set msi2intx modules parameter to 0. If the device is OK with msi2intx=0,
then please report it to KVM mailing list or me. We may prepare a blacklist for
the device that can't work in this mode.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang 6b9cc7fd46 KVM: Enable MSI for device assignment
We enable guest MSI and host MSI support in this patch. The userspace want to
enable MSI should set KVM_DEV_IRQ_ASSIGN_ENABLE_MSI in the assigned_irq's flag.
Function would return -ENOTTY if can't enable MSI, userspace shouldn't set MSI
Enable bit when KVM_ASSIGN_IRQ return -ENOTTY with
KVM_DEV_IRQ_ASSIGN_ENABLE_MSI.

Userspace can tell the support of MSI device from #ifdef KVM_CAP_DEVICE_MSI.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang f64769eb05 KVM: Add assigned_device_msi_dispatch()
The function is used to dispatch MSI to lapic according to MSI message
address and message data.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang 68b76f5167 KVM: Export ioapic_get_delivery_bitmask
It would be used for MSI in device assignment, for MSI dispatch.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang fbac7818d8 KVM: Clean up assigned_device_update_irq
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang 4f906c19ae KVM: Replace irq_requested with more generic irq_requested_type
Separate guest irq type and host irq type, for we can support guest using INTx
with host using MSI (but not opposite combination).

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang 00e3ed39e2 KVM: Separate update irq to a single function
Separate INTx enabling part to a independence function, so that we can add MSI
enabling part easily.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Sheng Yang 342ffb9300 KVM: Move ack notifier register and IRQ sourcd ID request
Distinguish common part for device assignment and INTx part, perparing for
refactor later.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Sheng Yang e7cacd40d2 KVM: Fix kernel allocated memory slot
Commit 7fd49de9773fdcb7b75e823b21c1c5dc1e218c14 "KVM: ensure that memslot
userspace addresses are page-aligned" broke kernel space allocated memory
slot, for the userspace_addr is invalid.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:25 +02:00
Hollis Blanchard 7874980922 KVM: ensure that memslot userspace addresses are page-aligned
Bad page translation and silent guest failure ensue if the userspace address is
not page-aligned.  I hit this problem using large (host) pages with qemu,
because qemu currently has a hardcoded 4096-byte alignment for guest memory
allocations.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:24 +02:00
Izik Eidus 2843099fee KVM: MMU: Fix aliased gfns treated as unaliased
Some areas of kvm x86 mmu are using gfn offset inside a slot without
unaliasing the gfn first.  This patch makes sure that the gfn will be
unaliased and add gfn_to_memslot_unaliased() to save the calculating
of the gfn unaliasing in case we have it unaliased already.

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:50 +02:00
Sheng Yang 6eb55818c0 KVM: Enable Function Level Reset for assigned device
Ideally, every assigned device should in a clear condition before and after
assignment, so that the former state of device won't affect later work.
Some devices provide a mechanism named Function Level Reset, which is
defined in PCI/PCI-e document. We should execute it before and after device
assignment.

(But sadly, the feature is new, and most device on the market now don't
support it. We are considering using D0/D3hot transmit to emulate it later,
but not that elegant and reliable as FLR itself.)

[Update: Reminded by Xiantao, execute FLR after we ensure that the device can
be assigned to the guest.]

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:49 +02:00
Sheng Yang e19e30effa KVM: IRQ ACK notifier should be used with in-kernel irqchip
Also remove unnecessary parameter of unregister irq ack notifier.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:47 +02:00
Jan Kiszka 26df99c6c5 KVM: Kick NMI receiving VCPU
Kick the NMI receiving VCPU in case the triggering caller runs in a
different context.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:42 +02:00
Sheng Yang 5550af4df1 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>
2008-10-28 14:21:34 +02:00
Xiantao Zhang 2f74977191 KVM: Move irqchip_in_kernel() from ioapic.h to irq.h
Moving irqchip_in_kernel() from ioapic.h to irq.h.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:36 +02:00
Xiantao Zhang 3de42dc094 KVM: Separate irq ack notification out of arch/x86/kvm/irq.c
Moving irq ack notification logic as common, and make
it shared with ia64 side.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:35 +02:00
Xiantao Zhang c77fb9dc7a KVM: Change is_mmio_pfn to kvm_is_mmio_pfn, and make it common for all archs
Add a kvm_ prefix to avoid polluting kernel's name space.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:34 +02:00
Xiantao Zhang 8a98f6648a KVM: Move device assignment logic to common code
To share with other archs, this patch moves device assignment
logic to common parts.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:33 +02:00
Zhang xiantao 371c01b28e KVM: Device Assignment: Move vtd.c from arch/x86/kvm/ to virt/kvm/
Preparation for kvm/ia64 VT-d support.

Signed-off-by: Zhang xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:32 +02:00
Weidong Han e5fcfc821a KVM: Device Assignment: Map mmio pages into VT-d page table
Assigned device could DMA to mmio pages, so also need to map mmio pages
into VT-d page table.

Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:29 +02:00
Weidong Han 271b05281f KVM: Remove useless intel-iommu.h header inclusion
Currently "#include <linux/intel-iommu.h>" is not needed in
virt/kvm/kvm_main.c.

Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:11 +02:00
Glauber Costa 7d8fece678 KVM: Don't destroy vcpu in case vcpu_setup fails
One of vcpu_setup responsibilities is to do mmu initialization.
However, in case we fail in kvm_arch_vcpu_reset, before we get the
chance to init mmu. OTOH, vcpu_destroy will attempt to destroy mmu,
triggering a bug. Keeping track of whether or not mmu is initialized
would unnecessarily complicate things. Rather, we just make return,
making sure any needed uninitialization is done before we return, in
case we fail.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:10 +02:00
Marcelo Tosatti 4c2155ce81 KVM: switch to get_user_pages_fast
Convert gfn_to_pfn to use get_user_pages_fast, which can do lockless
pagetable lookups on x86. Kernel compilation on 4-way guest is 3.7%
faster on VMX.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:06 +02:00
Marcelo Tosatti 777b3f49d2 KVM: opencode gfn_to_page in kvm_vm_fault
kvm_vm_fault is invoked with mmap_sem held in read mode. Since gfn_to_page
will be converted to get_user_pages_fast, which requires this lock NOT
to be held, switch to opencoded get_user_pages.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:05 +02:00
Ben-Ami Yassour 62c476c7c7 KVM: Device Assignment with VT-d
Based on a patch by: Kay, Allen M <allen.m.kay@intel.com>

This patch enables PCI device assignment based on VT-d support.
When a device is assigned to the guest, the guest memory is pinned and
the mapping is updated in the VT-d IOMMU.

[Amit: Expose KVM_CAP_IOMMU so we can check if an IOMMU is present
and also control enable/disable from userspace]

Signed-off-by: Kay, Allen M <allen.m.kay@intel.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Ben-Ami Yassour <benami@il.ibm.com>
Signed-off-by: Amit Shah <amit.shah@qumranet.com>

Acked-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 14:25:04 +02:00
Marcelo Tosatti d76901750a 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>
2008-10-15 10:15:26 +02:00
Avi Kivity d657c7335b KVM: Don't call get_user_pages(.force = 1)
This is esoteric and only needed to break COW on MAP_SHARED mappings.  Since
KVM no longer does these sorts of mappings, breaking COW on them is no longer
necessary.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:23 +02:00
Xiantao Zhang 26815a648e KVM: ia64: add a dummy irq ack notification
Before enabling notify_acked_irq for ia64, leave the related APIs as
nop-op first.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:21 +02:00
Dave Hansen fa3795a730 KVM: Reduce stack usage in kvm_vcpu_ioctl()
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:18 +02:00
Ben-Ami Yassour cbff90a7ca KVM: direct mmio pfn check
Userspace may specify memory slots that are backed by mmio pages rather than
normal RAM.  In some cases it is not enough to identify these mmio pages
by pfn_valid().  This patch adds checking the PageReserved as well.

Signed-off-by: Ben-Ami Yassour <benami@il.ibm.com>
Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:17 +02:00
Marcelo Tosatti f52447261b KVM: irq ack notification
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>
2008-10-15 10:15:16 +02:00
Christian Ehrhardt 3f7f95c65e KVM: kvmtrace: replace get_cycles with ktime_get v3
The current kvmtrace code uses get_cycles() while the interpretation would be
easier using using nanoseconds. ktime_get() should give at least the same
accuracy as get_cycles on all architectures (even better on 32bit archs) but
at a better unit (e.g. comparable between hosts with different frequencies.

[avi: avoid ktime_t in public header]

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:15 +02:00
Christian Ehrhardt e32c8f2c07 KVM: kvmtrace: Remove use of bit fields in kvm trace structure
This patch fixes kvmtrace use on big endian systems. When using bit fields the
compiler will lay data out in the wrong order expected when laid down into a
file.
This fixes it by using one variable instead of using bit fields.

Signed-off-by: Jerone Young <jyoung5@us.ibm.com>
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:14 +02:00
Andrea Arcangeli e930bffe95 KVM: Synchronize guest physical memory map to host virtual memory map
Synchronize changes to host virtual addresses which are part of
a KVM memory slot to the KVM shadow mmu.  This allows pte operations
like swapping, page migration, and madvise() to transparently work
with KVM.

Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-29 12:33:53 +03:00
Andrea Arcangeli 604b38ac03 KVM: Allow browsing memslots with mmu_lock
This allows reading memslots with only the mmu_lock hold for mmu
notifiers that runs in atomic context and with mmu_lock held.

Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-29 12:33:50 +03:00
Ulrich Drepper 7d9dbca342 flag parameters: anon_inode_getfd extension
This patch just extends the anon_inode_getfd interface to take an additional
parameter with a flag value.  The flag value is passed on to
get_unused_fd_flags in anticipation for a use with the O_CLOEXEC flag.

No actual semantic changes here, the changed callers all pass 0 for now.

[akpm@linux-foundation.org: KVM fix]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:27 -07:00
Avi Kivity 597a5f551e KVM: Adjust smp_call_function_mask() callers to new requirements
smp_call_function_mask() now complains when called in a preemptible context;
adjust its callers accordingly.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 14:29:54 +03:00
Marcelo Tosatti 34d4cb8fca KVM: MMU: nuke shadowed pgtable pages and ptes on memslot destruction
Flush the shadow mmu before removing regions to avoid stale entries.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:40 +03:00
Carsten Otte eff0114ac3 KVM: s390: dont allocate dirty bitmap
This patch #ifdefs the bitmap array for dirty tracking. We don't have dirty
tracking on s390 today, and we'd love to use our storage keys to store the
dirty information for migration. Therefore, we won't need this array at all,
and due to our limited amount of vmalloc space this limits the amount of guests
we can run.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:36 +03:00
Tan, Li 9ef621d3be KVM: Support mixed endian machines
Currently kvmtrace is not portable. This will prevent from copying a
trace file from big-endian target to little-endian workstation for analysis.
In the patch, kernel outputs metadata containing a magic number to trace
log, and changes 64-bit words to be u64 instead of a pair of u32s.

Signed-off-by: Tan Li <li.tan@intel.com>
Acked-by: Jerone Young <jyoung5@us.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:32 +03:00
Laurent Vivier 5f94c1741b KVM: Add coalesced MMIO support (common part)
This patch adds all needed structures to coalesce MMIOs.
Until an architecture uses it, it is not compiled.

Coalesced MMIO introduces two ioctl() to define where are the MMIO zones that
can be coalesced:

- KVM_REGISTER_COALESCED_MMIO registers a coalesced MMIO zone.
  It requests one parameter (struct kvm_coalesced_mmio_zone) which defines
  a memory area where MMIOs can be coalesced until the next switch to
  user space. The maximum number of MMIO zones is KVM_COALESCED_MMIO_ZONE_MAX.

- KVM_UNREGISTER_COALESCED_MMIO cancels all registered zones inside
  the given bounds (bounds are also given by struct kvm_coalesced_mmio_zone).

The userspace client can check kernel coalesced MMIO availability by asking
ioctl(KVM_CHECK_EXTENSION) for the KVM_CAP_COALESCED_MMIO capability.
The ioctl() call to KVM_CAP_COALESCED_MMIO will return 0 if not supported,
or the page offset where will be stored the ring buffer.
The page offset depends on the architecture.

After an ioctl(KVM_RUN), the first page of the KVM memory mapped points to
a kvm_run structure. The offset given by KVM_CAP_COALESCED_MMIO is
an offset to the coalesced MMIO ring expressed in PAGE_SIZE relatively
to the address of the start of th kvm_run structure. The MMIO ring buffer
is defined by the structure kvm_coalesced_mmio_ring.

[akio: fix oops during guest shutdown]

Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Akio Takebe <takebe_akio@jp.fujitsu.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:31 +03:00
Laurent Vivier 92760499d0 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>
2008-07-20 12:42:30 +03:00
Sheng Yang 3419ffc8e4 KVM: IOAPIC/LAPIC: Enable NMI support
[avi: fix ia64 build breakage]

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:25 +03:00
Avi Kivity 7cc8883074 KVM: Remove decache_vcpus_on_cpu() and related callbacks
Obsoleted by the vmx-specific per-cpu list.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:42:25 +03:00
Avi Kivity 4ecac3fd6d KVM: Handle virtualization instruction #UD faults during reboot
KVM turns off hardware virtualization extensions during reboot, in order
to disassociate the memory used by the virtualization extensions from the
processor, and in order to have the system in a consistent state.
Unfortunately virtual machines may still be running while this goes on,
and once virtualization extensions are turned off, any virtulization
instruction will #UD on execution.

Fix by adding an exception handler to virtualization instructions; if we get
an exception during reboot, we simply spin waiting for the reset to complete.
If it's a true exception, BUG() so we can have our stack trace.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:41:43 +03:00
Anthony Liguori 2e2e3738af KVM: Handle vma regions with no backing page
This patch allows VMAs that contain no backing page to be used for guest
memory.  This is useful for assigning mmio regions to a guest.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:40:49 +03:00
Christian Borntraeger 1e1c65e03e KVM: remove long -> void *user -> long cast
kvm_dev_ioctl casts the arg value to void __user *, just to recast it
again to long. This seems unnecessary.

According to objdump the binary code on x86 is unchanged by this patch.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:40:46 +03:00
Ingo Molnar 1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Mark McLoughlin 35baff256d KVM: IOAPIC: Fix level-triggered irq injection hang
The "remote_irr" variable is used to indicate an interrupt
which has been received by the LAPIC, but not acked.

In our EOI handler, we unset remote_irr and re-inject the
interrupt if the interrupt line is still asserted.

However, we do not set remote_irr here, leading to a
situation where if kvm_ioapic_set_irq() is called, then we go
ahead and call ioapic_service(). This means that IRR is
re-asserted even though the interrupt is currently in service
(i.e. LAPIC IRR is cleared and ISR/TMR set)

The issue with this is that when the currently executing
interrupt handler finishes and writes LAPIC EOI, then TMR is
unset and EOI sent to the IOAPIC. Since IRR is now asserted,
but TMR is not, then when the second interrupt is handled,
no EOI is sent and if there is any pending interrupt, it is
not re-injected.

This fixes a hang only seen while running mke2fs -j on an
8Gb virtio disk backed by a fully sparse raw file, with
aliguori "avoid fragmented virtio-blk transfers by copying"
changes.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-06 11:05:35 +03:00
Jens Axboe 15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Jens Axboe 8691e5a8f6 smp_call_function: get rid of the unused nonatomic/retry argument
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:35 +02:00
Avi Kivity 4fa6b9c5dc KVM: ioapic: fix lost interrupt when changing a device's irq
The ioapic acknowledge path translates interrupt vectors to irqs.  It
currently uses a first match algorithm, stopping when it finds the first
redirection table entry containing the vector.  That fails however if the
guest changes the irq to a different line, leaving the old redirection table
entry in place (though masked).  Result is interrupts not making it to the
guest.

Fix by always scanning the entire redirection table.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-06-24 12:23:55 +03:00
Marcelo Tosatti ff4b9df877 KVM: IOAPIC: only set remote_irr if interrupt was injected
There's a bug in the IOAPIC code for level-triggered interrupts. Its
relatively easy to trigger by sharing (virtio-blk + usbtablet was the
testcase, initially reported by Gerd von Egidy).

The "remote_irr" variable is used to indicate accepted but not yet acked
interrupts. Its cleared from the EOI handler.

Problem is that the EOI handler clears remote_irr unconditionally, even
if it reinjected another pending interrupt.

In that case, kvm_ioapic_set_irq() proceeds to ioapic_service() which
sets remote_irr even if it failed to inject (since the IRR was high due
to EOI reinjection).

Since the TMR bit has been cleared by the first EOI, the second one
fails to clear remote_irr.

End result is interrupt line dead.

Fix it by setting remote_irr only if a new pending interrupt has been
generated (and the TMR bit for vector in question set).

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-06-06 21:32:39 +03:00
Marcelo Tosatti e5c239cfd5 KVM: Fix kvm_vcpu_block() task state race
There's still a race in kvm_vcpu_block(), if a wake_up_interruptible()
call happens before the task state is set to TASK_INTERRUPTIBLE:

CPU0                            CPU1

kvm_vcpu_block

add_wait_queue

kvm_cpu_has_interrupt = 0
                                set interrupt
                                if (waitqueue_active())
                                        wake_up_interruptible()

kvm_cpu_has_pending_timer
kvm_arch_vcpu_runnable
signal_pending

set_current_state(TASK_INTERRUPTIBLE)
schedule()

Can be fixed by using prepare_to_wait() which sets the task state before
testing for the wait condition.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-05-18 14:37:12 +03:00
Sheng Yang 0d15029895 KVM: Export necessary function for EPT
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-05-04 14:44:40 +03:00
Al Viro 2030a42cec [PATCH] sanitize anon_inode_getfd()
a) none of the callers even looks at inode or file returned by anon_inode_getfd()
b) any caller that would try to look at those would be racy, since by the time
it returns we might have raced with close() from another thread and that
file would be pining for fjords.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-01 13:08:50 -04:00
Al Viro 66c0b394f0 KVM: kill file->f_count abuse in kvm
Use kvm own refcounting instead of playing with ->filp->f_count.
That will allow to get rid of a lot of crap in anon_inode_getfd() and
kill a race in kvm_dev_ioctl_create_vm() (file might have been closed
immediately by another thread, so ->filp might point to already freed
struct file when we get around to setting it).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 18:21:46 +03:00
Hollis Blanchard 76f7c87902 KVM: Rename debugfs_dir to kvm_debugfs_dir
It's a globally exported symbol now.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 18:21:36 +03:00
Marcelo Tosatti 62d9f0dbc9 KVM: add ioctls to save/store mpstate
So userspace can save/restore the mpstate during migration.

[avi: export the #define constants describing the value]
[christian: add s390 stubs]
[avi: ditto for ia64]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 18:21:16 +03:00
Marcelo Tosatti 3d80840d96 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>
2008-04-27 12:04:11 +03:00
Feng(Eric) Liu d4c9ff2d1b KVM: Add kvm trace userspace interface
This interface allows user a space application to read the trace of kvm
related events through relayfs.

Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:01:22 +03:00
Anthony Liguori 35149e2129 KVM: MMU: Don't assume struct page for x86
This patch introduces a gfn_to_pfn() function and corresponding functions like
kvm_release_pfn_dirty().  Using these new functions, we can modify the x86
MMU to no longer assume that it can always get a struct page for any given gfn.

We don't want to eliminate gfn_to_page() entirely because a number of places
assume they can do gfn_to_page() and then kmap() the results.  When we support
IO memory, gfn_to_page() will fail for IO pages although gfn_to_pfn() will
succeed.

This does not implement support for avoiding reference counting for reserved
RAM or for IO memory.  However, it should make those things pretty straight
forward.

Since we're only introducing new common symbols, I don't think it will break
the non-x86 architectures but I haven't tested those.  I've tested Intel,
AMD, NPT, and hugetlbfs with Windows and Linux guests.

[avi: fix overflow when shifting left pfns by adding casts]

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:01:15 +03:00
Izik Eidus d39f13b0da KVM: add vm refcounting
the main purpose of adding this functions is the abilaty to release the
spinlock that protect the kvm list while still be able to do operations
on a specific kvm in a safe way.

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:56 +03:00
Xiantao Zhang 3e4bb3ac9e KVM: Use kzalloc to avoid allocating kvm_regs from kernel stack
Since the size of kvm_regs is too big to allocate from kernel stack on ia64,
use kzalloc to allocate it.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:26 +03:00
Marcelo Tosatti 05da45583d KVM: MMU: large page support
Create large pages mappings if the guest PTE's are marked as such and
the underlying memory is hugetlbfs backed.  If the largepage contains
write-protected pages, a large pte is not used.

Gives a consistent 2% improvement for data copies on ram mounted
filesystem, without NPT/EPT.

Anthony measures a 4% improvement on 4-way kernbench, with NPT.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:25 +03:00
Marcelo Tosatti 2e53d63acb KVM: MMU: ignore zapped root pagetables
Mark zapped root pagetables as invalid and ignore such pages during lookup.

This is a problem with the cr3-target feature, where a zapped root table fools
the faulting code into creating a read-only mapping. The result is a lockup
if the instruction can't be emulated.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:25 +03:00
Andrea Arcangeli 0aac03f07b KVM: Disable pagefaults during copy_from_user_inatomic()
With CONFIG_PREEMPT=n, this is needed in order to disable the fault-in
code from sleeping.

Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:18 +03:00
Avi Kivity adb1ff4675 KVM: Limit vcpu mmap size to one page on non-x86
The second page is only needed on archs that support pio.

Noted by Carsten Otte.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:17 +03:00
Avi Kivity 09566765ef KVM: Only x86 has pio
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:15 +03:00
Jan Engelhardt 5c5027425e KVM: constify function pointer tables
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:15 +03:00
Avi Kivity 8c35f237fb KVM: Route irq 0 to vcpu 0 exclusively
Some Linux versions allow the timer interrupt to be processed by more than
one cpu, leading to hangs due to tsc instability.  Work around the issue
by only disaptching the interrupt to vcpu 0.

Problem analyzed (and patch tested) by Sheng Yang.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-03-04 15:19:48 +02:00
Izik Eidus 72dc67a696 KVM: remove the usage of the mmap_sem for the protection of the memory slots.
This patch replaces the mmap_sem lock for the memory slots with a new
kvm private lock, it is needed beacuse untill now there were cases where
kvm accesses user memory while holding the mmap semaphore.

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-03-04 15:19:40 +02:00
Christoph Hellwig 8b88b0998e libfs: allow error return from simple attributes
Sometimes simple attributes might need to return an error, e.g. for
acquiring a mutex interruptibly.  In fact we have that situation in
spufs already which is the original user of the simple attributes.  This
patch merged the temporarily forked attributes in spufs back into the
main ones and allows to return errors.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <stefano.brivio@polimi.it>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg KH <greg@kroah.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:34 -08:00
Marcelo Tosatti aaee2c94f7 KVM: MMU: Switch to mmu spinlock
Convert the synchronization of the shadow handling to a separate mmu_lock
spinlock.

Also guard fetch() by mmap_sem in read-mode to protect against alias
and memslot changes.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:21 +02:00
Marcelo Tosatti 7ec5458821 KVM: Add kvm_read_guest_atomic()
In preparation for a mmu spinlock, add kvm_read_guest_atomic()
and use it in fetch() and prefetch_page().

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:20 +02:00
Marcelo Tosatti 10589a4699 KVM: MMU: Concurrent guest walkers
Do not hold kvm->lock mutex across the entire pagefault code,
only acquire it in places where it is necessary, such as mmu
hash list, active list, rmap and parent pte handling.

Allow concurrent guest walkers by switching walk_addr() to use
mmap_sem in read-mode.

And get rid of the lockless __gfn_to_page.

[avi: move kvm_mmu_pte_write() locking inside the function]
[avi: add locking for real mode]
[avi: fix cmpxchg locking]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:20 +02:00
Zhang Xiantao 0eb8f49848 KVM: Move ioapic code to common directory.
Move ioapic code to common, since IA64 also needs it.

Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:19 +02:00
Avi Kivity 0fce5623ba KVM: Move drivers/kvm/* to virt/kvm/
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:18 +02:00