Andrea Arcangeli [Thu, 12 Mar 2009 17:18:43 +0000 (18:18 +0100)]
KVM: Fix missing smp tlb flush in invlpg
When kvm emulates an invlpg instruction, it can drop a shadow pte, but
leaves the guest tlbs intact. This can cause memory corruption when
swapping out.
Without this the other cpu can still write to a freed host physical page.
tlb smp flush must happen if rmap_remove is called always before mmu_lock
is released because the VM will take the mmu_lock before it can finally add
the page to the freelist after swapout. mmu notifier makes it safe to flush
the tlb after freeing the page (otherwise it would never be safe) so we can do
a single flush for multiple sptes invalidated.
Cc: stable@kernel.org Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Hannes Eder [Sat, 21 Feb 2009 01:19:13 +0000 (02:19 +0100)]
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>
Amit Shah [Thu, 28 Feb 2008 10:36:15 +0000 (16:06 +0530)]
KVM: is_long_mode() should check for EFER.LMA
is_long_mode currently checks the LongModeEnable bit in
EFER instead of the LongModeActive bit. This is wrong, but
we survived this till now since it wasn't triggered. This
breaks guests that go from long mode to compatibility mode.
This is noticed on a solaris guest and fixes bug #1842160
Signed-off-by: Amit Shah <amit.shah@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Amit Shah [Fri, 20 Feb 2009 17:23:37 +0000 (22:53 +0530)]
KVM: VMX: Update necessary state when guest enters long mode
setup_msrs() should be called when entering long mode to save the
shadow state for the 64-bit guest state.
Using vmx_set_efer() in enter_lmode() removes some duplicated code
and also ensures we call setup_msrs(). We can safely pass the value
of shadow_efer to vmx_set_efer() as no other bits in the efer change
while enabling long mode (guest first sets EFER.LME, then sets CR0.PG
which causes a vmexit where we activate long mode).
Joerg Roedel [Thu, 19 Feb 2009 11:18:56 +0000 (12:18 +0100)]
KVM: MMU: Fix another largepage memory leak
In the paging_fetch function rmap_remove is called after setting a large
pte to non-present. This causes rmap_remove to not drop the reference to
the large page. The result is a memory leak of that page.
Andre Przywara [Sun, 11 Jan 2009 21:39:44 +0000 (22:39 +0100)]
KVM: SVM: set accessed bit for VMCB segment selectors
In the segment descriptor _cache_ the accessed bit is always set
(although it can be cleared in the descriptor itself). Since Intel
checks for this condition on a VMENTRY, set this bit in the AMD path
to enable cross vendor migration.
Cc: stable@kernel.org Signed-off-by: Andre Przywara <andre.przywara@amd.com> Acked-By: Amit Shah <amit.shah@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Gleb Natapov [Wed, 4 Feb 2009 15:28:14 +0000 (17:28 +0200)]
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>
Joerg Roedel [Wed, 18 Feb 2009 13:08:59 +0000 (14:08 +0100)]
KVM: MMU: remove redundant check in mmu_set_spte
The following code flow is unnecessary:
if (largepage)
was_rmapped = is_large_pte(*shadow_pte);
else
was_rmapped = 1;
The is_large_pte() function will always evaluate to one here because the
(largepage && !is_large_pte) case is already handled in the first
if-clause. So we can remove this check and set was_rmapped to one always
here.
Joerg Roedel [Wed, 18 Feb 2009 13:08:58 +0000 (14:08 +0100)]
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.
Gerd Hoffmann [Wed, 4 Feb 2009 16:52:04 +0000 (17:52 +0100)]
KVM: Fix kvmclock on !constant_tsc boxes
kvmclock currently falls apart on machines without constant tsc.
This patch fixes it. Changes:
* keep tsc frequency in a per-cpu variable.
* handle kvmclock update using a new request flag, thus checking
whenever we need an update each time we enter guest context.
* use a cpufreq notifier to track frequency changes and force
kvmclock updates.
* send ipis to kick cpu out of guest context if needed to make
sure the guest doesn't see stale values.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Sheng Yang [Tue, 10 Feb 2009 05:57:06 +0000 (13:57 +0800)]
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>
Alexander Graf [Mon, 2 Feb 2009 15:23:51 +0000 (16:23 +0100)]
KVM: Add FFXSR support
AMD K10 CPUs implement the FFXSR feature that gets enabled using
EFER. Let's check if the virtual CPU description includes that
CPUID feature bit and allow enabling it then.
This is required for Windows Server 2008 in Hyper-V mode.
v2 adds CPUID capability exposure
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Jes Sorensen [Wed, 21 Jan 2009 14:16:43 +0000 (15:16 +0100)]
KVM: ia64: dynamic nr online cpus
Account for number of online cpus and use that in loops iterating over
the list of vpus instead of scanning the full array unconditionally.
This patch is a building block to facilitate allowing to bump up
the size of MAX_VCPUS significantly.
This patch fixes the SET PREFIX interrupt if triggered by userspace.
Until now, it was not necessary, but life migration will need it. In
addition, it helped me creating SMP support for my kvm_crashme tool
(lets kvm execute random guest memory content).
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: s390: Fix problem state check for b2 intercepts
The kernel handles some priviledged instruction exits. While I was
unable to trigger such an exit from guest userspace, the code should
check for supervisor state before emulating a priviledged instruction.
I also renamed kvm_s390_handle_priv to kvm_s390_handle_b2. After all
there are non priviledged b2 instructions like stck (store clock).
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM on s390 does not support the ESA/390 architecture. We refuse to
change the architecture mode and print a warning. This patch removes
the printk for several reasons:
o A malicious guest can flood host dmesg
o The old message had no newline
o there is no connection between the message and the failing guest
This patch simply removes the printk. We already set the condition
code to 3 - the guest knows that something went wrong.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Xiantao Zhang [Wed, 21 Jan 2009 03:21:27 +0000 (11:21 +0800)]
KVM: ia64: Implement some pal calls needed for windows 2008
For windows 2008, it needs more pal calls to implement for booting.
In addition, also changes the name of set_{sal, pal}_call_result to
get_{sal,pal}_call_result for readability.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Mon, 19 Jan 2009 12:57:52 +0000 (14:57 +0200)]
KVM: Avoid using CONFIG_ in userspace visible headers
Kconfig symbols are not available in userspace, and are not stripped by
headers-install. Avoid their use by adding #defines in <asm/kvm.h> to
suit each architecture.
Avi Kivity [Wed, 19 Nov 2008 11:58:46 +0000 (13:58 +0200)]
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.
Marcelo Tosatti [Thu, 8 Jan 2009 19:44:19 +0000 (17:44 -0200)]
KVM: MMU: drop zeroing on mmu_memory_cache_alloc
Zeroing on mmu_memory_cache_alloc is unnecessary since:
- Smaller areas are pre-allocated with kmem_cache_zalloc.
- Page pointed by ->spt is overwritten with prefetch_page
and entries in page pointed by ->gfns are initialized
before reading.
[avi: zeroing pages is unnecessary]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Sun, 4 Jan 2009 15:10:50 +0000 (17:10 +0200)]
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.
Alexander Graf [Mon, 5 Jan 2009 15:02:47 +0000 (16:02 +0100)]
KVM: SVM: Add microcode patch level dummy
VMware ESX checks if the microcode level is correct when using a barcelona
CPU, in order to see if it actually can use SVM. Let's tell it we're on the
safe side...
Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Sun, 4 Jan 2009 22:53:19 +0000 (00:53 +0200)]
KVM: VMX: Prevent exit handler from running if emulating due to invalid state
If we've just emulated an instruction, we won't have any valid exit
reason and associated information.
Fix by moving the clearing of the emulation_required flag to the exit handler.
This way the exit handler can notice that we've been emulating and abort
early.
KVM: ppc: split out common Book E instruction emulation
The Book E code will be shared with e500.
I've left PID in kvmppc_core_emulate_op() just so that we don't need to move
kvmppc_set_pid() right now. Once we have the e500 implementation, we can
probably share that too.
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
This commit change the name of emulator_read_std into kvm_read_guest_virt,
and add new function name kvm_write_guest_virt that allow writing into a
guest virtual address.
Signed-off-by: Izik Eidus <ieidus@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Fix it by initializating the offset of each vcpu relative to vm creation
time, and moving it from vmx_vcpu_reset to vmx_vcpu_setup, out of the
APIC MP init path.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Tue, 23 Dec 2008 17:46:01 +0000 (19:46 +0200)]
KVM: Fix vmload and friends misinterpreted as lidt
The AMD SVM instruction family all overload the 0f 01 /3 opcode, further
multiplexing on the three r/m bits. But the code decided that anything that
isn't a vmmcall must be an lidt (which shares the 0f 01 /3 opcode, for the
case that mod = 3).
Fix by aborting emulation if this isn't a vmmcall.
Avi Kivity [Sun, 21 Dec 2008 17:27:36 +0000 (19:27 +0200)]
KVM: MMU: Segregate mmu pages created with different cr4.pge settings
Don't allow a vcpu with cr4.pge cleared to use a shadow page created with
cr4.pge set; this might cause a cr3 switch not to sync ptes that have the
global bit set (the global bit has no effect if !cr4.pge).
This can only occur on smp with different cr4.pge settings for different
vcpus (since a cr4 change will resync the shadow ptes), but there's no
cost to being correct here.
Jan Kiszka [Mon, 15 Dec 2008 12:52:10 +0000 (13:52 +0100)]
KVM: x86: Virtualize debug registers
So far KVM only had basic x86 debug register support, once introduced to
realize guest debugging that way. The guest itself was not able to use
those registers.
This patch now adds (almost) full support for guest self-debugging via
hardware registers. It refactors the code, moving generic parts out of
SVM (VMX was already cleaned up by the KVM_SET_GUEST_DEBUG patches), and
it ensures that the registers are properly switched between host and
guest.
This patch also prepares debug register usage by the host. The latter
will (once wired-up by the following patch) allow for hardware
breakpoints/watchpoints in guest code. If this is enabled, the guest
will only see faked debug registers without functionality, but with
content reflecting the guest's modifications.
Tested on Intel only, but SVM /should/ work as well, but who knows...
Known limitations: Trapping on tss switch won't work - most probably on
Intel.
Credits also go to Joerg Roedel - I used his once posted debugging
series as platform for this patch.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Jan Kiszka [Mon, 15 Dec 2008 12:52:10 +0000 (13:52 +0100)]
KVM: VMX: Allow single-stepping when uninterruptible
When single-stepping over STI and MOV SS, we must clear the
corresponding interruptibility bits in the guest state. Otherwise
vmentry fails as it then expects bit 14 (BS) in pending debug exceptions
being set, but that's not correct for the guest debugging case.
Note that clearing those bits is safe as we check for interruptibility
based on the original state and do not inject interrupts or NMIs if
guest interruptibility was blocked.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Jan Kiszka [Mon, 15 Dec 2008 12:52:10 +0000 (13:52 +0100)]
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>