Commit Graph

150 Commits

Author SHA1 Message Date
Marcelo Tosatti
84261923d3 KVM: protect concurrent make_all_cpus_request
make_all_cpus_request contains a race condition which can
trigger false request completed status, as follows:

CPU0                                              CPU1

if (test_and_set_bit(req,&vcpu->requests))
   ....                                        	   if (test_and_set_bit(req,&vcpu->requests))
   ..                                                  return
proceed to smp_call_function_many(wait=1)

Use a spinlock to serialize concurrent CPUs.

Cc: stable@kernel.org
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-28 14:10:29 +03:00
Izik Eidus
e244584fe3 KVM: Fix dirty bit tracking for slots with large pages
When slot is already allocated and being asked to be tracked we need
to break the large pages.

This code flush the mmu when someone ask a slot to start dirty bit
tracking.

Cc: stable@kernel.org
Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-28 14:10:29 +03:00
Yinghai Lu
aee74f3bb3 kvm: remove the duplicated cpumask_clear
zalloc_cpumask_var already cleared it.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11 20:04:37 -07:00
Avi Kivity
09f8ca74ae KVM: Prevent overflow in largepages calculation
If userspace specifies a memory slot that is larger than 8 petabytes, it
could overflow the largepages variable.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 15:18:16 +03:00
Avi Kivity
ac04527f79 KVM: Disable large pages on misaligned memory slots
If a slots guest physical address and host virtual address unequal (mod
large page size), then we would erronously try to back guest large pages
with host large pages.  Detect this misalignment and diable large page
support for the trouble slot.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 15:17:58 +03:00
Marcelo Tosatti
b43b1901ad KVM: take mmu_lock when updating a deleted slot
kvm_handle_hva relies on mmu_lock protection to safely access
the memslot structures.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:54 +03:00
Marcelo Tosatti
547de29e5b KVM: protect assigned dev workqueue, int handler and irq acker
kvm_assigned_dev_ack_irq is vulnerable to a race condition with the
interrupt handler function. It does:

        if (dev->host_irq_disabled) {
                enable_irq(dev->host_irq);
                dev->host_irq_disabled = false;
        }

If an interrupt triggers before the host->dev_irq_disabled assignment,
it will disable the interrupt and set dev->host_irq_disabled to true.

On return to kvm_assigned_dev_ack_irq, dev->host_irq_disabled is set to
false, and the next kvm_assigned_dev_ack_irq call will fail to reenable
it.

Other than that, having the interrupt handler and work handlers run in
parallel sounds like asking for trouble (could not spot any obvious
problem, but better not have to, its fragile).

CC: sheng.yang@intel.com
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:53 +03:00
Chris Wright
efbc100c20 KVM: Trivial format fix in setup_routing_entry()
Remove extra tab.

Signed-off-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:50 +03:00
Sheng Yang
8e1c18157d KVM: VMX: Disable VMX when system shutdown
Intel TXT(Trusted Execution Technology) required VMX off for all cpu to work
when system shutdown.

CC: Joseph Cihula <joseph.cihula@intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:50 +03:00
Sheng Yang
522c68c441 KVM: Enable snooping control for supported hardware
Memory aliases with different memory type is a problem for guest. For the guest
without assigned device, the memory type of guest memory would always been the
same as host(WB); but for the assigned device, some part of memory may be used
as DMA and then set to uncacheable memory type(UC/WC), which would be a conflict of
host memory type then be a potential issue.

Snooping control can guarantee the cache correctness of memory go through the
DMA engine of VT-d.

[avi: fix build on ia64]

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:50 +03:00
Gleb Natapov
78646121e9 KVM: Fix interrupt unhalting a vcpu when it shouldn't
kvm_vcpu_block() unhalts vpu on an interrupt/timer without checking
if interrupt window is actually opened.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:33 +03:00
Gleb Natapov
09cec75488 KVM: Timer event should not unconditionally unhalt vcpu.
Currently timer events are processed before entering guest mode. Move it
to main vcpu event loop since timer events should be processed even while
vcpu is halted.  Timer may cause interrupt/nmi to be injected and only then
vcpu will be unhalted.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:33 +03:00
Gleb Natapov
f00be0cae4 KVM: MMU: do not free active mmu pages in free_mmu_pages()
free_mmu_pages() should only undo what alloc_mmu_pages() does.
Free mmu pages from the generic VM destruction function, kvm_destroy_vm().

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:30 +03:00
Sheng Yang
e56d532f20 KVM: Device assignment framework rework
After discussion with Marcelo, we decided to rework device assignment framework
together. The old problems are kernel logic is unnecessary complex. So Marcelo
suggest to split it into a more elegant way:

1. Split host IRQ assign and guest IRQ assign. And userspace determine the
combination. Also discard msi2intx parameter, userspace can specific
KVM_DEV_IRQ_HOST_MSI | KVM_DEV_IRQ_GUEST_INTX in assigned_irq->flags to
enable MSI to INTx convertion.

2. Split assign IRQ and deassign IRQ. Import two new ioctls:
KVM_ASSIGN_DEV_IRQ and KVM_DEASSIGN_DEV_IRQ.

This patch also fixed the reversed _IOR vs _IOW in definition(by deprecated the
old interface).

[avi: replace homemade bitcount() by hweight_long()]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:29 +03:00
Gleb Natapov
58c2dde17d KVM: APIC: get rid of deliver_bitmask
Deliver interrupt during destination matching loop.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
e1035715ef KVM: change the way how lowest priority vcpu is calculated
The new way does not require additional loop over vcpus to calculate
the one with lowest priority as one is chosen during delivery bitmap
construction.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
343f94fe4d KVM: consolidate ioapic/ipi interrupt delivery logic
Use kvm_apic_match_dest() in kvm_get_intr_delivery_bitmask() instead
of duplicating the same code. Use kvm_get_intr_delivery_bitmask() in
apic_send_ipi() to figure out ipi destination instead of reimplementing
the logic.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
a53c17d21c KVM: ioapic/msi interrupt delivery consolidation
ioapic_deliver() and kvm_set_msi() have code duplication. Move
the code into ioapic_deliver_entry() function and call it from
both places.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
6da7e3f643 KVM: APIC: kvm_apic_set_irq deliver all kinds of interrupts
Get rid of ioapic_inj_irq() and ioapic_inj_nmi() functions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:26 +03:00
Sheng Yang
74a3a8f152 KVM: Merge kvm_ioapic_get_delivery_bitmask into kvm_get_intr_delivery_bitmask
Gleb fixed bitmap ops usage in kvm_ioapic_get_delivery_bitmask.

Sheng merged two functions, as well as fixed several issues in
kvm_get_intr_delivery_bitmask
1. deliver_bitmask is a bitmap rather than a unsigned long intereger.
2. Lowest priority target bitmap wrong calculated by mistake.
3. Prevent potential NULL reference.
4. Declaration in include/kvm_host.h caused powerpc compilation warning.
5. Add warning for guest broadcast interrupt with lowest priority delivery mode.
6. Removed duplicate bitmap clean up in caller of kvm_get_intr_delivery_bitmask.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:26 +03:00
Sheng Yang
d510d6cc65 KVM: Enable MSI-X for KVM assigned device
This patch finally enable MSI-X.

What we need for MSI-X:
1. Intercept one page in MMIO region of device. So that we can get guest desired
MSI-X table and set up the real one. Now this have been done by guest, and
transfer to kernel using ioctl KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY.

2. Information for incoming interrupt. Now one device can have more than one
interrupt, and they are all handled by one workqueue structure. So we need to
identify them. The previous patch enable gsi_msg_pending_bitmap get this done.

3. Mapping from host IRQ to guest gsi as well as guest gsi to real MSI/MSI-X
message address/data. We used same entry number for the host and guest here, so
that it's easy to find the correlated guest gsi.

What we lack for now:
1. The PCI spec said nothing can existed with MSI-X table in the same page of
MMIO region, except pending bits. The patch ignore pending bits as the first
step (so they are always 0 - no pending).

2. The PCI spec allowed to change MSI-X table dynamically. That means, the OS
can enable MSI-X, then mask one MSI-X entry, modify it, and unmask it. The patch
didn't support this, and Linux also don't work in this way.

3. The patch didn't implement MSI-X mask all and mask single entry. I would
implement the former in driver/pci/msi.c later. And for single entry, userspace
should have reposibility to handle it.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:23 +03:00
Sheng Yang
2350bd1f62 KVM: Add MSI-X interrupt injection logic
We have to handle more than one interrupt with one handler for MSI-X. Avi
suggested to use a flag to indicate the pending. So here is it.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:23 +03:00
Sheng Yang
c1e0151429 KVM: Ioctls for init MSI-X entry
Introduce KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY two ioctls.

This two ioctls are used by userspace to specific guest device MSI-X entry
number and correlate MSI-X entry with GSI during the initialization stage.

MSI-X should be well initialzed before enabling.

Don't support change MSI-X entry number for now.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:23 +03:00
Sheng Yang
bfd349d073 KVM: bit ops for deliver_bitmap
It's also convenient when we extend KVM supported vcpu number in the future.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:22 +03:00
Sheng Yang
110c2faeba KVM: Update intr delivery func to accept unsigned long* bitmap
Would be used with bit ops, and would be easily extended if KVM_MAX_VCPUS is
increased.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:22 +03:00
Sheng Yang
e5871be0f5 KVM: Change API of kvm_ioapic_get_delivery_bitmask
In order to use with bit ops.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:22 +03:00
Sheng Yang
116191b69b KVM: Unify the delivery of IOAPIC and MSI interrupts
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:22 +03:00
Sheng Yang
cf9e4e15e8 KVM: Split IOAPIC structure
Prepared for reuse ioapic_redir_entry for MSI.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:21 +03:00
Avi Kivity
8437a61770 kvm: fix kvm reboot crash when MAXSMP is used
one system was found there is crash during reboot then kvm/MAXSMP
Sending all processes the KILL signal...                              done
Please stand by while rebooting the system...
[ 1721.856538] md: stopping all md devices.
[ 1722.852139] kvm: exiting hardware virtualization
[ 1722.854601] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1722.872219] IP: [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1722.877955] PGD 0
[ 1722.880042] Oops: 0000 [] SMP
[ 1722.892548] last sysfs file: /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/host0/target0:2:0/0:2:0:0/vendor
[ 1722.900977] CPU 9
[ 1722.912606] Modules linked in:
[ 1722.914226] Pid: 0, comm: swapper Not tainted 2.6.30-rc7-tip-01843-g2305324-dirty  ...
[ 1722.932589] RIP: 0010:[<ffffffff8102c6b6>]  [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1722.942709] RSP: 0018:ffffc900010b6ed8  EFLAGS: 00010046
[ 1722.956121] RAX: 0000000000000000 RBX: ffffc9000e253140 RCX: 0000000000000009
[ 1722.972202] RDX: 000000000000b020 RSI: ffffc900010c3220 RDI: ffffffffffffd790
[ 1722.977399] RBP: ffffc900010b6f08 R08: 0000000000000000 R09: 0000000000000000
[ 1722.995149] R10: 00000000000004b8 R11: 966912b6c78fddbd R12: 0000000000000009
[ 1723.011551] R13: 000000000000b020 R14: 0000000000000009 R15: 0000000000000000
[ 1723.019898] FS:  0000000000000000(0000) GS:ffffc900010b3000(0000) knlGS:0000000000000000
[ 1723.034389] CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
[ 1723.041164] CR2: 0000000000000000 CR3: 0000000001001000 CR4: 00000000000006e0
[ 1723.056192] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1723.072546] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1723.080562] Process swapper (pid: 0, threadinfo ffff88107e464000, task ffff88047e5a2550)
[ 1723.096144] Stack:
[ 1723.099071]  0000000000000046 ffffc9000e253168 966912b6c78fddbd ffffc9000e253140
[ 1723.115471]  ffff880c7d4304d0 ffffc9000e253168 ffffc900010b6f28 ffffffff81011022
[ 1723.132428]  ffffc900010b6f48 966912b6c78fddbd ffffc900010b6f48 ffffffff8100b83b
[ 1723.141973] Call Trace:
[ 1723.142981]  <IRQ> <0> [<ffffffff81011022>] kvm_arch_hardware_disable+0x26/0x3c
[ 1723.158153]  [<ffffffff8100b83b>] hardware_disable+0x3f/0x55
[ 1723.172168]  [<ffffffff810b95f6>] generic_smp_call_function_interrupt+0x76/0x13c
[ 1723.178836]  [<ffffffff8104cbea>] smp_call_function_interrupt+0x3a/0x5e
[ 1723.194689]  [<ffffffff81035bf3>] call_function_interrupt+0x13/0x20
[ 1723.199750]  <EOI> <0> [<ffffffff814ad3b4>] ? acpi_idle_enter_c1+0xd3/0xf4
[ 1723.217508]  [<ffffffff814ad3ae>] ? acpi_idle_enter_c1+0xcd/0xf4
[ 1723.232172]  [<ffffffff814ad4bc>] ? acpi_idle_enter_bm+0xe7/0x2ce
[ 1723.235141]  [<ffffffff81a8d93f>] ? __atomic_notifier_call_chain+0x0/0xac
[ 1723.253381]  [<ffffffff818c3dff>] ? menu_select+0x58/0xd2
[ 1723.258179]  [<ffffffff818c2c9d>] ? cpuidle_idle_call+0xa4/0xf3
[ 1723.272828]  [<ffffffff81034085>] ? cpu_idle+0xb8/0x101
[ 1723.277085]  [<ffffffff81a80163>] ? start_secondary+0x1bc/0x1d7
[ 1723.293708] Code: b0 00 00 65 48 8b 04 25 28 00 00 00 48 89 45 e0 31 c0 48 8b 04 cd 30 ee 27 82 49 89 cc 49 89 d5 48 8b 04 10 48 8d b8 90 d7 ff ff <48> 8b 87 70 28 00 00 48 8d 98 90 d7 ff ff eb 16 e8 e9 fe ff ff
[ 1723.335524] RIP  [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1723.342076]  RSP <ffffc900010b6ed8>
[ 1723.352021] CR2: 0000000000000000
[ 1723.354348] ---[ end trace e2aec53dae150aa1 ]---

it turns out that we need clear cpus_hardware_enabled in that case.

Reported-and-tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-09 22:30:28 +09:30
Avi Kivity
a4c0364be3 KVM: Explicity initialize cpus_hardware_enabled
Under CONFIG_MAXSMP, cpus_hardware_enabled is allocated from the heap and
not statically initialized.  This causes a crash on reboot when kvm thinks
vmx is enabled on random nonexistent cpus and accesses nonexistent percpu
lists.

Fix by explicitly clearing the variable.

Cc: stable@kernel.org
Reported-and-tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-08 10:50:46 +03:00
Jan Kiszka
4cd481f68d KVM: Fix overlapping check for memory slots
When checking for overlapping slots on registration of a new one, kvm
currently also considers zero-length (ie. deleted) slots and rejects
requests incorrectly. This finally denies user space from joining slots.
Fix the check by skipping deleted slots and advertise this via a
KVM_CAP_JOIN_MEMORY_REGIONS_WORKS.

Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-04-22 13:52:09 +03:00
Avi Kivity
99894a799f KVM: MMU: Fix off-by-one calculating large page count
The large page initialization code concludes there are two large pages spanned
by a slot covering 1 (small) page starting at gfn 1.  This is incorrect, and
also results in incorrect write_count initialization in some cases (base = 1,
npages = 513 for example).

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-04-22 13:52:09 +03:00
Sheng Yang
36463146ff KVM: Get support IRQ routing entry counts
In capability probing ioctl.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:14 +02:00
Hannes Eder
cded19f396 KVM: fix sparse warnings: Should it be static?
Impact: Make symbols static.

Fix this sparse warnings:
  arch/x86/kvm/mmu.c:992:5: warning: symbol 'mmu_pages_add' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1124:5: warning: symbol 'mmu_pages_next' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1144:6: warning: symbol 'mmu_pages_clear_parents' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2037:5: warning: symbol 'kvm_read_guest_virt' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2067:5: warning: symbol 'kvm_write_guest_virt' was not declared. Should it be static?
  virt/kvm/irq_comm.c:220:5: warning: symbol 'setup_routing_entry' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:14 +02:00
Xiantao Zhang
6b08035f3e KVM: ia64: Fix the build errors due to lack of macros related to MSI.
Include the newly introduced msidef.h to solve the build issues.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:13 +02:00
Weidong Han
4a906e49f1 KVM: fix kvm_vm_ioctl_deassign_device
only need to set assigned_dev_id for deassignment, use
match->flags to judge and deassign it.

Acked-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:12 +02:00
Gleb Natapov
71450f7885 KVM: Report IRQ injection status for MSI delivered interrupts
Return number of CPUs interrupt was successfully injected into or -1 if
none.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:11 +02:00
Gleb Natapov
4925663a07 KVM: Report IRQ injection status to userspace.
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>
2009-03-24 11:03:11 +02:00
Joerg Roedel
fc5659c8c6 KVM: MMU: handle compound pages in kvm_is_mmio_pfn
The function kvm_is_mmio_pfn is called before put_page is called on a
page by KVM. This is a problem when when this function is called on some
struct page which is part of a compund page. It does not test the
reserved flag of the compound page but of the struct page within the
compount page. This is a problem when KVM works with hugepages allocated
at boot time. These pages have the reserved bit set in all tail pages.
Only the flag in the compount head is cleared. KVM would not put such a
page which results in a memory leak.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:09 +02:00
Sheng Yang
79950e1073 KVM: Use irq routing API for MSI
Merge MSI userspace interface with IRQ routing table. Notice the API have been
changed, and using IRQ routing table would be the only interface kvm-userspace
supported.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:09 +02:00
Marcelo Tosatti
44882eed2e KVM: make irq ack notifications aware of routing table
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>
2009-03-24 11:03:08 +02:00
Avi Kivity
399ec807dd KVM: Userspace controlled irq routing
Currently KVM has a static routing from GSI numbers to interrupts (namely,
0-15 are mapped 1:1 to both PIC and IOAPIC, and 16:23 are mapped 1:1 to
the IOAPIC).  This is insufficient for several reasons:

- HPET requires non 1:1 mapping for the timer interrupt
- MSIs need a new method to assign interrupt numbers and dispatch them
- ACPI APIC mode needs to be able to reassign the PCI LINK interrupts to the
  ioapics

This patch implements an interrupt routing table (as a linked list, but this
can be easily changed) and a userspace interface to replace the table.  The
routing table is initialized according to the current hardwired mapping.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:06 +02:00
Avi Kivity
75858a84a6 KVM: Interrupt mask notifiers for ioapic
Allow clients to request notifications when the guest masks or unmasks a
particular irq line.  This complements irq ack notifications, as the guest
will not ack an irq line that is masked.

Currently implemented for the ioapic only.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:03 +02:00
Sheng Yang
17071fe74f KVM: Add support to disable MSI for assigned device
MSI is always enabled by default for msi2intx=1. But if msi2intx=0, we
have to disable MSI if guest require to do so.

The patch also discard unnecessary msi2intx judgment if guest want to update
MSI state.

Notice KVM_DEV_IRQ_ASSIGN_MSI_ACTION is a mask which should cover all MSI
related operations, though we only got one for now.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:02 +02:00
Jan Kiszka
d0bfb940ec KVM: New guest debug interface
This rips out the support for KVM_DEBUG_GUEST and introduces a new IOCTL
instead: KVM_SET_GUEST_DEBUG. The IOCTL payload consists of a generic
part, controlling the "main switch" and the single-step feature. The
arch specific part adds an x86 interface for intercepting both types of
debug exceptions separately and re-injecting them when the host was not
interested. Moveover, the foundation for guest debugging via debug
registers is layed.

To signal breakpoint events properly back to userland, an arch-specific
data block is now returned along KVM_EXIT_DEBUG. For x86, the arch block
contains the PC, the debug exception, and relevant debug registers to
tell debug events properly apart.

The availability of this new interface is signaled by
KVM_CAP_SET_GUEST_DEBUG. Empty stubs for not yet supported archs are
provided.

Note that both SVM and VTX are supported, but only the latter was tested
yet. Based on the experience with all those VTX corner case, I would be
fairly surprised if SVM will work out of the box.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:49 +02:00
Mark McLoughlin
682edb4c01 KVM: Fix assigned devices circular locking dependency
kvm->slots_lock is outer to kvm->lock, so take slots_lock
in kvm_vm_ioctl_assign_device() before taking kvm->lock,
rather than taking it in kvm_iommu_map_memslots().

Cc: stable@kernel.org
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:39 +02:00
Sheng Yang
d7cff1c376 KVM: Fix INTx for device assignment
Missing buckets and wrong parameter for free_irq()

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:38 +02:00
Sheng Yang
ba4cef31d5 KVM: Fix racy in kvm_free_assigned_irq
In the past, kvm_get_kvm() and kvm_put_kvm() was called in assigned device irq
handler and interrupt_work, in order to prevent cancel_work_sync() in
kvm_free_assigned_irq got a illegal state when waiting for interrupt_work done.
But it's tricky and still got two problems:

1. A bug ignored two conditions that cancel_work_sync() would return true result
in a additional kvm_put_kvm().

2. If interrupt type is MSI, we would got a window between cancel_work_sync()
and free_irq(), which interrupt would be injected again...

This patch discard the reference count used for irq handler and interrupt_work,
and ensure the legal state by moving the free function at the very beginning of
kvm_destroy_vm(). And the patch fix the second bug by disable irq before
cancel_work_sync(), which may result in nested disable of irq but OK for we are
going to free it.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:36 +02:00
Sheng Yang
ad8ba2cd44 KVM: Add kvm_arch_sync_events to sync with asynchronize events
kvm_arch_sync_events is introduced to quiet down all other events may happen
contemporary with VM destroy process, like IRQ handler and work struct for
assigned device.

For kvm_arch_sync_events is called at the very beginning of kvm_destroy_vm(), so
the state of KVM here is legal and can provide a environment to quiet down other
events.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:36 +02:00
Marcelo Tosatti
85db06e514 KVM: mmu_notifiers release method
The destructor for huge pages uses the backing inode for adjusting
hugetlbfs accounting.

Hugepage mappings are destroyed by exit_mmap, after
mmu_notifier_release, so there are no notifications through
unmap_hugepage_range at this point.

The hugetlbfs inode can be freed with pages backed by it referenced
by the shadow. When the shadow releases its reference, the huge page
destructor will access a now freed inode.

Implement the release operation for kvm mmu notifiers to release page
refs before the hugetlbfs inode is gone.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:35 +02:00