powerpc/kvm: common sw breakpoint instr across ppc
This patch extends the use of illegal instruction as software
breakpoint instruction across the ppc platform. Patch extends
booke program interrupt code to support software breakpoint.
This patch adds kernel side support for software breakpoint.
Design is that, by using an illegal instruction, we trap to hypervisor
via Emulation Assistance interrupt, where we check for the illegal instruction
and accordingly we return to Host or Guest. Patch also adds support for
software breakpoint in PR KVM.
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Mon, 1 Sep 2014 09:01:58 +0000 (12:01 +0300)]
KVM: PPC: e500mc: Add support for single threaded vcpus on e6500 core
ePAPR represents hardware threads as cpu node properties in device tree.
So with existing QEMU, hardware threads are simply exposed as vcpus with
one hardware thread.
The e6500 core shares TLBs between hardware threads. Without tlb write
conditional instruction, the Linux kernel uses per core mechanisms to
protect against duplicate TLB entries.
The guest is unable to detect real siblings threads, so it can't use the
TLB protection mechanism. An alternative solution is to use the hypervisor
to allocate different lpids to guest's vcpus that runs simultaneous on real
siblings threads. On systems with two threads per core this patch halves
the size of the lpid pool that the allocator sees and use two lpids per VM.
Use even numbers to speedup vcpu lpid computation with consecutive lpids
per VM: vm1 will use lpids 2 and 3, vm2 lpids 4 and 5, and so on.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: fix spelling] Signed-off-by: Alexander Graf <agraf@suse.de>
Paul Mackerras [Tue, 2 Sep 2014 06:14:43 +0000 (16:14 +1000)]
KVM: PPC: Book3S HV: Only accept host PVR value for guest PVR
Since the guest can read the machine's PVR (Processor Version Register)
directly and see the real value, we should disallow userspace from
setting any value for the guest's PVR other than the real host value.
Therefore this makes kvm_arch_vcpu_set_sregs_hv() check the supplied
PVR value and return an error if it is different from the host value,
which has been put into vcpu->arch.pvr at vcpu creation time.
Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
Paul Mackerras [Tue, 2 Sep 2014 06:14:42 +0000 (16:14 +1000)]
KVM: PPC: Book3S HV: Increase timeout for grabbing secondary threads
Occasional failures have been seen with split-core mode and migration
where the message "KVM: couldn't grab cpu" appears. This increases
the length of time that we wait from 1ms to 10ms, which seems to
work around the issue.
Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Mon, 1 Sep 2014 10:17:43 +0000 (13:17 +0300)]
KVM: PPC: Remove shared defines for SPE and AltiVec interrupts
We currently decide at compile-time which of the SPE or AltiVec units to
support exclusively. Guard kernel defines with CONFIG_SPE_POSSIBLE and
CONFIG_PPC_E500MC and remove shared defines.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Mon, 1 Sep 2014 14:19:56 +0000 (17:19 +0300)]
KVM: PPC: Remove the tasklet used by the hrtimer
Powerpc timer implementation is a copycat version of s390. Now that they removed
the tasklet with commit ea74c0ea1b24a6978a6ebc80ba4dbc7b7848b32d follow this
optimization.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Bharat Bhushan [Wed, 13 Aug 2014 09:09:44 +0000 (14:39 +0530)]
KVM: PPC: BOOKE: Emulate debug registers and exception
This patch emulates debug registers and debug exception
to support guest using debug resource. This enables running
gdb/kgdb etc in guest.
On BOOKE architecture we cannot share debug resources between QEMU and
guest because:
When QEMU is using debug resources then debug exception must
be always enabled. To achieve this we set MSR_DE and also set
MSRP_DEP so guest cannot change MSR_DE.
When emulating debug resource for guest we want guest
to control MSR_DE (enable/disable debug interrupt on need).
So above mentioned two configuration cannot be supported
at the same time. So the result is that we cannot share
debug resources between QEMU and Guest on BOOKE architecture.
In the current design QEMU gets priority over guest, this means that if
QEMU is using debug resources then guest cannot use them and if guest is
using debug resource then QEMU can overwrite them.
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Wed, 20 Aug 2014 13:36:24 +0000 (16:36 +0300)]
KVM: PPC: Make ONE_REG powerpc generic
Make ONE_REG generic for server and embedded architectures by moving
kvm_vcpu_ioctl_get_one_reg() and kvm_vcpu_ioctl_set_one_reg() functions
to powerpc layer.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Wed, 20 Aug 2014 13:36:23 +0000 (16:36 +0300)]
KVM: PPC: Book3e: Add AltiVec support
Add AltiVec support in KVM for Book3e. FPU support gracefully reuse host
infrastructure so follow the same approach for AltiVec.
Book3e specification defines shared interrupt numbers for SPE and AltiVec
units. Still SPE is present in e200/e500v2 cores while AltiVec is present in
e6500 core. So we can currently decide at compile-time which of the SPE or
AltiVec units to support exclusively by using CONFIG_SPE_POSSIBLE and
CONFIG_PPC_E500MC defines. As Alexander Graf suggested, keep SPE and AltiVec
exception handlers distinct to improve code readability.
Guests have the privilege to enable AltiVec, so we always need to support
AltiVec in KVM and implicitly in host to reflect interrupts and to save/restore
the unit context. KVM will be loaded on cores with AltiVec unit only if
CONFIG_ALTIVEC is defined. Use this define to guard KVM AltiVec logic.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Wed, 20 Aug 2014 13:36:22 +0000 (16:36 +0300)]
KVM: PPC: Book3E: Increase FPU laziness
Increase FPU laziness by loading the guest state into the unit before entering
the guest instead of doing it on each vcpu schedule. Without this improvement
an interrupt may claim floating point corrupting guest state.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Wed, 20 Aug 2014 13:09:04 +0000 (16:09 +0300)]
powerpc/booke: Revert SPE/AltiVec common defines for interrupt numbers
Book3E specification defines shared interrupt numbers for SPE and AltiVec
units. Still SPE is present in e200/e500v2 cores while AltiVec is present in
e6500 core. So we can currently decide at compile-time which unit to support
exclusively. As Alexander Graf suggested, this will improve code readability
especially in KVM.
Use distinct defines to identify SPE/AltiVec interrupt numbers, reverting c58ce397 and 6b310fc5 patches that added common defines.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Mihai Caraman [Wed, 20 Aug 2014 13:09:03 +0000 (16:09 +0300)]
powerpc/booke: Restrict SPE exception handlers to e200/e500 cores
SPE exception handlers are now defined for 32-bit e500mc cores even though
SPE unit is not present and CONFIG_SPE is undefined.
Restrict SPE exception handlers to e200/e500 cores adding CONFIG_SPE_POSSIBLE
and consequently guard __stup_ivors and __setup_cpu functions.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Bharat Bhushan [Wed, 6 Aug 2014 06:38:55 +0000 (12:08 +0530)]
KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
Guest visible debug register and hardware visible debug registers are
same, so ther is no need to have arch->shadow_dbg_reg, instead use
arch->dbg_reg.
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Bharat Bhushan [Wed, 6 Aug 2014 06:38:54 +0000 (12:08 +0530)]
KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
Dbsr is not visible to userspace and we do not think any need to
expose this to userspace because:
Userspace cannot inject debug interrupt to guest (as this
does not know guest ability to handle debug interrupt), so
userspace will always clear DBSR.
Now if userspace has to always clear DBSR in KVM_EXIT_DEBUG
handling then clearing dbsr in kernel looks simple as this
avoid doing SET_SREGS/set_one_reg() to clear DBSR
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Bharat Bhushan [Wed, 6 Aug 2014 06:38:53 +0000 (12:08 +0530)]
KVM: PPC: BOOKE: Allow guest to change MSR_DE
This patch changes the default behavior of MSRP_DEP, that is
guest is not allowed to change the MSR_DE, to guest can change
MSR_DE. When userspace is debugging guest then it override the
default behavior and set MSRP_DEP. This stops guest to change
MSR_DE when userspace is debugging guest.
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Bharat Bhushan [Wed, 6 Aug 2014 06:38:51 +0000 (12:08 +0530)]
KVM: PPC: BOOKE: allow debug interrupt at "debug level"
Debug interrupt can be either "critical level" or "debug level".
There are separate set of save/restore registers used for different level.
Example: DSRR0/DSRR1 are used for "debug level" and CSRR0/CSRR1
are used for critical level debug interrupt.
Using CPU_FTR_DEBUG_LVL_EXC to decide which interrupt level to be used.
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
kvm: Make init_rmode_identity_map() return 0 on success.
In init_rmode_identity_map(), there two variables indicating the return
value, r and ret, and it return 0 on error, 1 on success. The function
is only called by vmx_create_vcpu(), and ret is redundant.
This patch removes the redundant variable, and makes init_rmode_identity_map()
return 0 on success, -errno on failure.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm: Remove ept_identity_pagetable from struct kvm_arch.
kvm_arch->ept_identity_pagetable holds the ept identity pagetable page. But
it is never used to refer to the page at all.
In vcpu initialization, it indicates two things:
1. indicates if ept page is allocated
2. indicates if a memory slot for identity page is initialized
Actually, kvm_arch->ept_identity_pagetable_done is enough to tell if the ept
identity pagetable is initialized. So we can remove ept_identity_pagetable.
NOTE: In the original code, ept identity pagetable page is pinned in memroy.
As a result, it cannot be migrated/hot-removed. After this patch, since
kvm_arch->ept_identity_pagetable is removed, ept identity pagetable page
is no longer pinned in memory. And it can be migrated/hot-removed.
Will Deacon [Tue, 2 Sep 2014 09:27:36 +0000 (10:27 +0100)]
KVM: VFIO: register kvm_device_ops dynamically
Now that we have a dynamic means to register kvm_device_ops, use that
for the VFIO kvm device, instead of relying on the static table.
This is achieved by a module_init call to register the ops with KVM.
Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Alex Williamson <Alex.Williamson@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that we have a dynamic means to register kvm_device_ops, use that
for the ARM VGIC, instead of relying on the static table.
Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Will Deacon [Tue, 2 Sep 2014 09:27:33 +0000 (10:27 +0100)]
KVM: device: add simple registration mechanism for kvm_device_ops
kvm_ioctl_create_device currently has knowledge of all the device types
and their associated ops. This is fairly inflexible when adding support
for new in-kernel device emulations, so move what we currently have out
into a table, which can support dynamic registration of ops by new
drivers for virtual hardware.
Cc: Alex Williamson <Alex.Williamson@redhat.com> Cc: Alex Graf <agraf@suse.de> Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, we call ioapic_service() immediately when we find the irq is still
active during eoi broadcast. But for real hardware, there's some delay between
the EOI writing and irq delivery. If we do not emulate this behavior, and
re-inject the interrupt immediately after the guest sends an EOI and re-enables
interrupts, a guest might spend all its time in the ISR if it has a broken
handler for a level-triggered interrupt.
Such livelock actually happens with Windows guests when resuming from
hibernation.
As there's no way to recognize the broken handle from new raised ones, this patch
delays an interrupt if 10.000 consecutive EOIs found that the interrupt was
still high. The guest can then make a little forward progress, until a proper
IRQ handler is set or until some detection routine in the guest (such as
Linux's note_interrupt()) recognizes the situation.
Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 11 Sep 2014 09:51:02 +0000 (11:51 +0200)]
KVM: x86: make apic_accept_irq tracepoint more generic
Initially the tracepoint was added only to the APIC_DM_FIXED case,
also because it reported coalesced interrupts that only made sense
for that case. However, the coalesced argument is not used anymore
and tracing other delivery modes is useful, so hoist the call out
of the switch statement.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 11 Sep 2014 09:09:33 +0000 (11:09 +0200)]
Merge tag 'kvm-s390-next-20140910' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next
KVM: s390: Fixes and features for next (3.18)
1. Crypto/CPACF support: To enable the MSA4 instructions we have to
provide a common control structure for each SIE control block
2. Two cleanups found by a static code checker: one redundant assignment
and one useless if
3. Fix the page handling of the diag10 ballooning interface. If the
guest freed the pages at absolute 0 some checks and frees were
incorrect
4. Limit guests to 16TB
5. Add __must_check to interrupt injection code
KVM: s390/cmm: Fix prefix handling for diag 10 balloon
The old handling of prefix pages was broken in the diag10 ballooner.
We now rely on gmap_discard to check for start > end and do a
slow path if the prefix swap pages are affected:
1. discard the pages from start to prefix
2. discard the absolute 0 pages
3. discard the pages after prefix swap to end
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
KVM: s390: get rid of constant condition in ipte_unlock_simple
Due to the earlier check we know that ipte_lock_count must be 0.
No need to add a useless if. Let's make clear that we are going
to always wakeup when we execute that code.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Currently we fill up a full 5 level page table to hold the guest
mapping. Since commit "support gmap page tables with less than 5
levels" we can do better.
Having more than 4 TB might be useful for some testing scenarios,
so let's just limit ourselves to 16TB guest size.
Having more than that is totally untested as I do not have enough
swap space/memory.
We continue to allow ucontrol the full size.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Tony Krowiak [Fri, 27 Jun 2014 18:46:01 +0000 (14:46 -0400)]
KVM: CPACF: Enable MSA4 instructions for kvm guest
We have to provide a per guest crypto block for the CPUs to
enable MSA4 instructions. According to icainfo on z196 or
later this enables CCM-AES-128, CMAC-AES-128, CMAC-AES-192
and CMAC-AES-256.
Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[split MSA4/protected key into two patches]
Alex Bennée [Tue, 9 Sep 2014 16:27:19 +0000 (17:27 +0100)]
KVM: fix api documentation of KVM_GET_EMULATED_CPUID
It looks like when this was initially merged it got accidentally included
in the following section. I've just moved it back in the correct section
and re-numbered it as other ioctls have been added since.
Alex Bennée [Tue, 9 Sep 2014 16:27:18 +0000 (17:27 +0100)]
KVM: document KVM_SET_GUEST_DEBUG api
In preparation for working on the ARM implementation I noticed the debug
interface was missing from the API document. I've pieced together the
expected behaviour from the code and commit messages written it up as
best I can.
The expression `vcpu->spin_loop.in_spin_loop' is always true,
because it is evaluated only when the condition
`!vcpu->spin_loop.in_spin_loop' is false.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Tue, 2 Sep 2014 11:23:06 +0000 (13:23 +0200)]
KVM: x86: propagate exception from permission checks on the nested page fault
Currently, if a permission error happens during the translation of
the final GPA to HPA, walk_addr_generic returns 0 but does not fill
in walker->fault. To avoid this, add an x86_exception* argument
to the translate_gpa function, and let it fill in walker->fault.
The nested_page_fault field will be true, since the walk_mmu is the
nested_mmu and translate_gpu instead operates on the "outer" (NPT)
instance.
Reported-by: Valentine Sinitsyn <valentine.sinitsyn@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Thu, 4 Sep 2014 17:46:15 +0000 (19:46 +0200)]
KVM: x86: skip writeback on injection of nested exception
If a nested page fault happens during emulation, we will inject a vmexit,
not a page fault. However because writeback happens after the injection,
we will write ctxt->eip from L2 into the L1 EIP. We do not write back
if an instruction caused an interception vmexit---do the same for page
faults.
Paolo Bonzini [Tue, 2 Sep 2014 11:24:12 +0000 (13:24 +0200)]
KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD
Bit 8 would be the "global" bit, which does not quite make sense for non-leaf
page table entries. Intel ignores it; AMD ignores it in PDEs, but reserves it
in PDPEs and PML4Es. The SVM test is relying on this behavior, so enforce it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
David Matlack [Mon, 18 Aug 2014 22:46:07 +0000 (15:46 -0700)]
kvm: x86: fix stale mmio cache bug
The following events can lead to an incorrect KVM_EXIT_MMIO bubbling
up to userspace:
(1) Guest accesses gpa X without a memory slot. The gfn is cached in
struct kvm_vcpu_arch (mmio_gfn). On Intel EPT-enabled hosts, KVM sets
the SPTE write-execute-noread so that future accesses cause
EPT_MISCONFIGs.
(2) Host userspace creates a memory slot via KVM_SET_USER_MEMORY_REGION
covering the page just accessed.
(3) Guest attempts to read or write to gpa X again. On Intel, this
generates an EPT_MISCONFIG. The memory slot generation number that
was incremented in (2) would normally take care of this but we fast
path mmio faults through quickly_check_mmio_pf(), which only checks
the per-vcpu mmio cache. Since we hit the cache, KVM passes a
KVM_EXIT_MMIO up to userspace.
This patch fixes the issue by using the memslot generation number
to validate the mmio cache.
Cc: stable@vger.kernel.org Signed-off-by: David Matlack <dmatlack@google.com>
[xiaoguangrong: adjust the code to make it simpler for stable-tree fix.] Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Tested-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
David Matlack [Mon, 18 Aug 2014 22:46:06 +0000 (15:46 -0700)]
kvm: fix potentially corrupt mmio cache
vcpu exits and memslot mutations can run concurrently as long as the
vcpu does not aquire the slots mutex. Thus it is theoretically possible
for memslots to change underneath a vcpu that is handling an exit.
If we increment the memslot generation number again after
synchronize_srcu_expedited(), vcpus can safely cache memslot generation
without maintaining a single rcu_dereference through an entire vm exit.
And much of the x86/kvm code does not maintain a single rcu_dereference
of the current memslots during each exit.
We can prevent the following case:
vcpu (CPU 0) | thread (CPU 1)
--------------------------------------------+--------------------------
1 vm exit |
2 srcu_read_unlock(&kvm->srcu) |
3 decide to cache something based on |
old memslots |
4 | change memslots
| (increments generation)
5 | synchronize_srcu(&kvm->srcu);
6 retrieve generation # from new memslots |
7 tag cache with new memslot generation |
8 srcu_read_unlock(&kvm->srcu) |
... |
<action based on cache occurs even |
though the caching decision was based |
on the old memslots> |
... |
<action *continues* to occur until next |
memslot generation change, which may |
be never> |
|
By incrementing the generation after synchronizing with kvm->srcu readers,
we ensure that the generation retrieved in (6) will become invalid soon
after (8).
Keeping the existing increment is not strictly necessary, but we
do keep it and just move it for consistency from update_memslots to
install_new_memslots. It invalidates old cached MMIOs immediately,
instead of having to wait for the end of synchronize_srcu_expedited,
which makes the code more clearly correct in case CPU 1 is preempted
right after synchronize_srcu() returns.
To avoid halving the generation space in SPTEs, always presume that the
low bit of the generation is zero when reconstructing a generation number
out of an SPTE. This effectively disables MMIO caching in SPTEs during
the call to synchronize_srcu_expedited. Using the low bit this way is
somewhat like a seqcount---where the protected thing is a cache, and
instead of retrying we can simply punt if we observe the low bit to be 1.
Cc: stable@vger.kernel.org Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Wed, 20 Aug 2014 12:29:21 +0000 (14:29 +0200)]
KVM: do not bias the generation number in kvm_current_mmio_generation
The next patch will give a meaning (a la seqcount) to the low bit of the
generation number. Ensure that it matches between kvm->memslots->generation
and kvm_current_mmio_generation().
Cc: stable@vger.kernel.org Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Fri, 29 Aug 2014 16:56:01 +0000 (18:56 +0200)]
KVM: x86: use guest maxphyaddr to check MTRR values
The check introduced in commit d7a2a246a1b5 (KVM: x86: #GP when attempts to write reserved bits of Variable Range MTRRs, 2014-08-19)
will break if the guest maxphyaddr is higher than the host's (which
sometimes happens depending on your hardware and how QEMU is
configured).
To fix this, use cpuid_maxphyaddr similar to how the APIC_BASE MSR
does already.
Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Tested-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Radim Krčmář [Thu, 28 Aug 2014 13:13:02 +0000 (15:13 +0200)]
KVM: static inline empty kvm_arch functions
Using static inline is going to save few bytes and cycles.
For example on powerpc, the difference is 700 B after stripping.
(5 kB before)
This patch also deals with two overlooked empty functions:
kvm_arch_flush_shadow was not removed from arch/mips/kvm/mips.c 2df72e9bc KVM: split kvm_arch_flush_shadow
and kvm_arch_sched_in never made it into arch/ia64/kvm/kvm-ia64.c. e790d9ef6 KVM: add kvm_arch_sched_in
Signed-off-by: Radim KrÄ\8dmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Fri, 29 Aug 2014 12:01:17 +0000 (14:01 +0200)]
KVM: forward declare structs in kvm_types.h
Opaque KVM structs are useful for prototypes in asm/kvm_host.h, to avoid
"'struct foo' declared inside parameter list" warnings (and consequent
breakage due to conflicting types).
Move them from individual files to a generic place in linux/kvm_types.h.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Alex Williamson [Fri, 11 Jul 2014 17:56:31 +0000 (11:56 -0600)]
KVM: x86 emulator: emulate MOVNTDQ
Windows 8.1 guest with NVIDIA driver and GPU fails to boot with an
emulation failure. The KVM spew suggests the fault is with lack of
movntdq emulation (courtesy of Paolo):
Nadav Amit [Fri, 29 Aug 2014 08:26:55 +0000 (11:26 +0300)]
KVM: vmx: VMXOFF emulation in vm86 should cause #UD
Unlike VMCALL, the instructions VMXOFF, VMLAUNCH and VMRESUME should cause a UD
exception in real-mode or vm86. However, the emulator considers all these
instructions the same for the matter of mode checks, and emulation upon exit
due to #UD exception.
As a result, the hypervisor behaves incorrectly on vm86 mode. VMXOFF, VMLAUNCH
or VMRESUME cause on vm86 exit due to #UD. The hypervisor then emulates these
instruction and inject #GP to the guest instead of #UD.
This patch creates a new group for these instructions and mark only VMCALL as
an instruction which can be emulated.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Tue, 26 Aug 2014 11:27:46 +0000 (13:27 +0200)]
KVM: x86: fix some sparse warnings
Sparse reports the following easily fixed warnings:
arch/x86/kvm/vmx.c:8795:48: sparse: Using plain integer as NULL pointer
arch/x86/kvm/vmx.c:2138:5: sparse: symbol vmx_read_l1_tsc was not declared. Should it be static?
arch/x86/kvm/vmx.c:6151:48: sparse: Using plain integer as NULL pointer
arch/x86/kvm/vmx.c:8851:6: sparse: symbol vmx_sched_in was not declared. Should it be static?
arch/x86/kvm/svm.c:2162:5: sparse: symbol svm_read_l1_tsc was not declared. Should it be static?
Wanpeng Li [Thu, 21 Aug 2014 11:46:50 +0000 (19:46 +0800)]
KVM: nVMX: nested TPR shadow/threshold emulation
This patch fix bug https://bugzilla.kernel.org/show_bug.cgi?id=61411
TPR shadow/threshold feature is important to speed up the Windows guest.
Besides, it is a must feature for certain VMM.
We map virtual APIC page address and TPR threshold from L1 VMCS. If
TPR_BELOW_THRESHOLD VM exit is triggered by L2 guest and L1 interested
in, we inject it into L1 VMM for handling.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
[Add PAGE_ALIGNED check, do not write useless virtual APIC page address
if TPR shadowing is disabled. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Christoffer Dall [Tue, 26 Aug 2014 12:00:38 +0000 (14:00 +0200)]
KVM: Unconditionally export KVM_CAP_USER_NMI
The idea between capabilities and the KVM_CHECK_EXTENSION ioctl is that
userspace can, at run-time, determine if a feature is supported or not.
This allows KVM to being supporting a new feature with a new kernel
version without any need to update user space. Unfortunately, since the
definition of KVM_CAP_USER_NMI was guarded by #ifdef
__KVM_HAVE_USER_NMI, such discovery still required a user space update.
Therefore, unconditionally export KVM_CAP_USER_NMI and change the
the typo in the comment for the IOCTL number definition as well.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Christoffer Dall [Tue, 26 Aug 2014 12:00:37 +0000 (14:00 +0200)]
KVM: Unconditionally export KVM_CAP_READONLY_MEM
The idea between capabilities and the KVM_CHECK_EXTENSION ioctl is that
userspace can, at run-time, determine if a feature is supported or not.
This allows KVM to being supporting a new feature with a new kernel
version without any need to update user space. Unfortunately, since the
definition of KVM_CAP_READONLY_MEM was guarded by #ifdef
__KVM_HAVE_READONLY_MEM, such discovery still required a user space
update.
Therefore, unconditionally export KVM_CAP_READONLY_MEM and change the
in-kernel conditional to rely on __KVM_HAVE_READONLY_MEM.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: s390/mm: fix up indentation of set_guest_storage_key
commit ab3f285f227f ("KVM: s390/mm: try a cow on read only pages for
key ops")' misaligned a code block. Let's fixup the indentation.
Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Tue, 26 Aug 2014 12:31:44 +0000 (14:31 +0200)]
Merge tag 'kvm-s390-next-20140825' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Fixes and features for 3.18 part 1
1. The usual cleanups: get rid of duplicate code, use defines, factor
out the sync_reg handling, additional docs for sync_regs, better
error handling on interrupt injection
2. We use KVM_REQ_TLB_FLUSH instead of open coding tlb flushes
3. Additional registers for kvm_run sync regs. This is usually not
needed in the fast path due to eventfd/irqfd, but kvm stat claims
that we reduced the overhead of console output by ~50% on my system
4. A rework of the gmap infrastructure. This is the 2nd step towards
host large page support (after getting rid of the storage key
dependency). We introduces two radix trees to store the guest-to-host
and host-to-guest translations. This gets us rid of most of
the page-table walks in the gmap code. Only one in __gmap_link is left,
this one is required to link the shadow page table to the process page
table. Finally this contains the plumbing to support gmap page tables
with less than 5 levels.
KVM: s390/mm: support gmap page tables with less than 5 levels
Add an addressing limit to the gmap address spaces and only allocate
the page table levels that are needed for the given limit. The limit
is fixed and can not be changed after a gmap has been created.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390/mm: use radix trees for guest to host mappings
Store the target address for the gmap segments in a radix tree
instead of using invalid segment table entries. gmap_translate
becomes a simple radix_tree_lookup, gmap_fault is split into the
address translation with gmap_translate and the part that does
the linking of the gmap shadow page table with the process page
table.
A second radix tree is used to keep the pointers to the segment
table entries for segments that are mapped in the guest address
space. On unmap of a segment the pointer is retrieved from the
radix tree and is used to carry out the segment invalidation in
the gmap shadow page table. As the radix tree can only store one
pointer, each host segment may only be mapped to exactly one
guest location.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Paolo Bonzini [Mon, 25 Aug 2014 13:37:00 +0000 (15:37 +0200)]
Merge tag 'kvm-s390-20140825' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
Here are two fixes for s390 KVM code that prevent:
1. a malicious user to trigger a kernel BUG
2. a malicious user to change the storage key of read-only pages
KVM: s390/mm: cleanup gmap function arguments, variable names
Make the order of arguments for the gmap calls more consistent,
if the gmap pointer is passed it is always the first argument.
In addition distinguish between guest address and user address
by naming the variables gaddr for a guest address and vmaddr for
a user address.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Jens Freimann [Mon, 11 Aug 2014 13:39:43 +0000 (15:39 +0200)]
KVM: s390: don't use kvm lock in interrupt injection code
The kvm lock protects us against vcpus going away, but they only go
away when the virtual machine is shut down. We don't need this
mutex here, so let's get rid of it.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: return -EFAULT if lowcore is not mapped during irq delivery
Currently we just kill the userspace process and exit the thread
immediatly without making sure that we don't hold any locks etc.
Improve this by making KVM_RUN return -EFAULT if the lowcore is not
mapped during interrupt delivery. To achieve this we need to pass
the return code of guest memory access routines used in interrupt
delivery all the way back to the KVM_RUN ioctl.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: implement KVM_REQ_TLB_FLUSH and make use of it
Use the KVM_REQ_TLB_FLUSH request in order to trigger tlb flushes instead
of manipulating the SIE control block whenever we need it. Also trigger it for
a control register sync directly instead of (ab)using kvm_s390_set_prefix().
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: synchronize more registers with kvm_run
In order to reduce the number of syscalls when dropping to user space, this
patch enables the synchronization of the following "registers" with kvm_run:
- ARCH0: CPU timer, clock comparator, TOD programmable register,
guest breaking-event register, program parameter
- PFAULT: pfault parameters (token, select, compare)
The registers are grouped to reduce the overhead when syncing.
As this grows the number of sync registers quite a bit, let's move the code
synchronizing registers with kvm_run from kvm_arch_vcpu_ioctl_run() into
separate helper routines.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This patch clarifies that kvm_dirty_regs are just a hint to the kernel and
that the kernel might just ignore some flags and sync the values (like done for
acrs and gprs now).
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390/mm: try a cow on read only pages for key ops
The PFMF instruction handler blindly wrote the storage key even if
the page was mapped R/O in the host. Lets try a COW before continuing
and bail out in case of errors.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: stable@vger.kernel.org
In the early days, we had some special handling for the
KVM_EXIT_S390_SIEIC exit, but this was gone in 2009 with commit d7b0b5eb3000 (KVM: s390: Make psw available on all exits, not
just a subset).
Now this switch statement is just a sanity check for userspace
not messing with the kvm_run structure. Unfortunately, this
allows userspace to trigger a kernel BUG. Let's just remove
this switch statement.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: stable@vger.kernel.org
Radim Krčmář [Thu, 21 Aug 2014 16:08:08 +0000 (18:08 +0200)]
KVM: VMX: dynamise PLE window
Window is increased on every PLE exit and decreased on every sched_in.
The idea is that we don't want to PLE exit if there is no preemption
going on.
We do this with sched_in() because it does not hold rq lock.
There are two new kernel parameters for changing the window:
ple_window_grow and ple_window_shrink
ple_window_grow affects the window on PLE exit and ple_window_shrink
does it on sched_in; depending on their value, the window is modifier
like this: (ple_window is kvm_intel's global)
Radim Krčmář [Thu, 21 Aug 2014 16:08:05 +0000 (18:08 +0200)]
KVM: add kvm_arch_sched_in
Introduce preempt notifiers for architecture specific code.
Advantage over creating a new notifier in every arch is slightly simpler
code and guaranteed call order with respect to kvm_sched_in.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We dont have to wait for a grace period if there is no oldpid that
we are going to free. putpid also checks for NULL, so this patch
only fences synchronize_rcu.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paolo Bonzini [Wed, 20 Aug 2014 08:08:23 +0000 (10:08 +0200)]
KVM: emulate: warn on invalid or uninitialized exception numbers
These were reported when running Jailhouse on AMD processors.
Initialize ctxt->exception.vector with an invalid exception number,
and warn if it remained invalid even though the emulator got
an X86EMUL_PROPAGATE_FAULT return code.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Wed, 20 Aug 2014 10:25:52 +0000 (13:25 +0300)]
KVM: x86: Clarify PMU related features bit manipulation
kvm_pmu_cpuid_update makes a lot of bit manuiplation operations, when in fact
there are already unions that can be used instead. Changing the bit
manipulation to the union for clarity. This patch does not change the
functionality.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Wanpeng Li [Wed, 20 Aug 2014 07:31:53 +0000 (15:31 +0800)]
KVM: vmx: fix ept reserved bits for 1-GByte page
EPT misconfig handler in kvm will check which reason lead to EPT
misconfiguration after vmexit. One of the reasons is that an EPT
paging-structure entry is configured with settings reserved for
future functionality. However, the handler can't identify if
paging-structure entry of reserved bits for 1-GByte page are
configured, since PDPTE which point to 1-GByte page will reserve
bits 29:12 instead of bits 7:3 which are reserved for PDPTE that
references an EPT Page Directory. This patch fix it by reserve
bits 29:12 for 1-GByte page.
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Mon, 18 Aug 2014 21:03:00 +0000 (00:03 +0300)]
KVM: x86: recalculate_apic_map after enabling apic
Currently, recalculate_apic_map ignores vcpus whose lapic is software disabled
through the spurious interrupt vector. However, once it is re-enabled, the map
is not recalculated. Therefore, if the guest OS configured DFR while lapic is
software-disabled, the map may be incorrect. This patch recalculates apic map
after software enabling the lapic.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Nadav Amit [Mon, 18 Aug 2014 19:42:13 +0000 (22:42 +0300)]
KVM: x86: Clear apic tsc-deadline after deadline
Intel SDM 10.5.4.1 says "When the timer generates an interrupt, it disarms
itself and clears the IA32_TSC_DEADLINE MSR".
This patch clears the MSR upon timer interrupt delivery which delivered on
deadline mode. Since the MSR may be reconfigured while an interrupt is
pending, causing the new value to be overriden, pending timer interrupts are
checked before setting a new deadline.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
projects / linux-beck.git / log