cleanup_srcu_struct on VM destruction remains broken:

BUG: unable to handle kernel paging request at ffffffffffffffff
IP: [<ffffffff802533d2>] srcu_read_lock+0x16/0x21
RIP: 0010:[<ffffffff802533d2>]  [<ffffffff802533d2>] srcu_read_lock+0x16/0x21
Call Trace:
 [<ffffffffa05354c4>] kvm_arch_vcpu_uninit+0x1b/0x48 [kvm]
 [<ffffffffa05339c6>] kvm_vcpu_uninit+0x9/0x15 [kvm]
 [<ffffffffa0569f7d>] vmx_free_vcpu+0x7f/0x8f [kvm_intel]
 [<ffffffffa05357b5>] kvm_arch_destroy_vm+0x78/0x111 [kvm]
 [<ffffffffa053315b>] kvm_put_kvm+0xd4/0xfe [kvm]

Move it to kvm_arch_destroy_vm.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Reported-by: NJan Kiszka <jan.kiszka@siemens.com>

All code in PPC KVM currently accesses gprs in the vcpu struct directly.

While there's nothing wrong with that wrt the current way gprs are stored
and loaded, it doesn't suffice for the PACA acceleration that will follow
in this patchset.

So let's just create little wrapper inline functions that we call whenever
a GPR needs to be read from or written to. The compiled code shouldn't really
change at all for now.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Required for SRCU convertion later.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Currently userspace has no chance to find out which virtual address space we're
in and resolve addresses. While that is a big problem for migration, it's also
unpleasent when debugging, as gdb and the monitor don't work on virtual
addresses.

This patch exports enough of the MMU segment state to userspace to make
debugging work and thus also includes the groundwork for migration.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

X86 CPUs need to have some magic happening to enable the virtualization
extensions on them. This magic can result in unpleasant results for
users, like blocking other VMMs from working (vmx) or using invalid TLB
entries (svm).

Currently KVM activates virtualization when the respective kernel module
is loaded. This blocks us from autoloading KVM modules without breaking
other VMMs.

To circumvent this problem at least a bit, this patch introduces on
demand activation of virtualization. This means, that instead
virtualization is enabled on creation of the first virtual machine
and disabled on destruction of the last one.

So using this, KVM can be easily autoloaded, while keeping other
hypervisors usable.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Not the incorrect -EINVAL.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Following S390's good example we should use hrtimers for the decrementer too!
This patch converts the timer from the old mechanism to hrtimers.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

PowerPC code handles dirty logging in the generic parts atm. While this
is great for "return -ENOTSUPP", we need to be rather target specific
when actually implementing it.

So let's split it to implementation specific code, so we can implement
it for book3s.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

[avi: make it build]
[avi: fold trace-arch.h into trace.h]

CC: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

[christian: remove unused variables on s390]
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

kvm_vcpu_block() unhalts vpu on an interrupt/timer without checking
if interrupt window is actually opened.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

After the rewrite of KVM's debug support, this code doesn't even build any
more.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

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: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

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: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NAvi Kivity <avi@redhat.com>

Existing KVM statistics are either just counters (kvm_stat) reported for
KVM generally or trace based aproaches like kvm_trace.
For KVM on powerpc we had the need to track the timings of the different exit
types. While this could be achieved parsing data created with a kvm_trace
extension this adds too much overhead (at least on embedded PowerPC) slowing
down the workloads we wanted to measure.

Therefore this patch adds a in-kernel exit timing statistic to the powerpc kvm
code. These statistic is available per vm&vcpu under the kvm debugfs directory.
As this statistic is low, but still some overhead it can be enabled via a
.config entry and should be off by default.

Since this patch touched all powerpc kvm_stat code anyway this code is now
merged and simplified together with the exit timing statistic code (still
working with exit timing disabled in .config).
Signed-off-by: NChristian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

However, some of these fields could be split into separate per-core structures
in the future.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This patch doesn't yet move all 44x-specific data into the new structure, but
is the first step down that path. In the future we may also want to create a
struct kvm_vcpu_booke.

Based on patch from Liu Yu <yu.liu@freescale.com>.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This introduces a set of core-provided hooks. For 440, some of these are
implemented by booke.c, with the rest in (the new) 44x.c.

Note that these hooks are link-time, not run-time. Since it is not possible to
build a single kernel for both e500 and 440 (for example), using function
pointers would only add overhead.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Commit 2a4aca11 ("powerpc/mm: Split
low level tlb invalidate for nohash processors") changed a call to
_tlbia to _tlbil_all but didn't include the header that defines
_tlbil_all, leading to a build failure on 440 if KVM is enabled.
This fixes it.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Currently, the various forms of low level TLB invalidations are all
implemented in misc_32.S for 32-bit processors, in a fairly scary
mess of #ifdef's and with interesting duplication such as a whole
bunch of code for FSL _tlbie and _tlbia which are no longer used.

This moves things around such that _tlbie is now defined in
hash_low_32.S and is only used by the 32-bit hash code, and all
nohash CPUs use the various _tlbil_* forms that are now moved to
a new file, tlb_nohash_low.S.

I moved all the definitions for that stuff out of
include/asm/tlbflush.h as they are really internal mm stuff, into
mm/mmu_decl.h

The code should have no functional changes.  I kept some variants
inline for trivial forms on things like 40x and 8xx.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When the VM exits, we must call put_page() for every page referenced in the
shadow TLB.

Without this patch, we usually leak 30-50 host pages (120 - 200 KiB with 4 KiB
pages). The maximum number of pages leaked is the size of our shadow TLB, 64
pages.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Track which TLB entries need to be written, instead of overwriting everything
below the high water mark. Typically only a single guest TLB entry will be
modified in a single exit.

Guest boot time performance improvement: about 15%.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Allow host userspace to program hardware debug registers to set breakpoints
inside guests.
Signed-off-by: NJerone Young <jyoung5@us.ibm.com>
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Flush the shadow mmu before removing regions to avoid stale entries.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch enables coalesced MMIO for powerpc architecture.
It defines KVM_MMIO_PAGE_OFFSET and KVM_CAP_COALESCED_MMIO.
It enables the compilation of coalesced_mmio.c.
Signed-off-by: NLaurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Obsoleted by the vmx-specific per-cpu list.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This reduces host CPU usage when the guest is idle. However, the guest must
set MSR[WE] in its idle loop, which Linux did not do until 2.6.26.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NJerone Young <jyoung5@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This functionality is definitely experimental, but is capable of running
unmodified PowerPC 440 Linux kernels as guests on a PowerPC 440 host. (Only
tested with 440EP "Bamboo" guests so far, but with appropriate userspace
support other SoC/board combinations should work.)

See Documentation/powerpc/kvm_440.txt for technical details.

[stephen: build fix]
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAvi Kivity <avi@qumranet.com>