Build on 32-bit PPC fails with the following error:
int kvm_vfio_ops_init(void)
^
In file included from arch/powerpc/kvm/../../../virt/kvm/vfio.c:21:0:
arch/powerpc/kvm/../../../virt/kvm/vfio.h:8:90: note: previous definition of ‘kvm_vfio_ops_init’ was here
arch/powerpc/kvm/../../../virt/kvm/vfio.c:292:6: error: redefinition of ‘kvm_vfio_ops_exit’
void kvm_vfio_ops_exit(void)
^
In file included from arch/powerpc/kvm/../../../virt/kvm/vfio.c:21:0:
arch/powerpc/kvm/../../../virt/kvm/vfio.h:12:91: note: previous definition of ‘kvm_vfio_ops_exit’ was here
scripts/Makefile.build:258: recipe for target arch/powerpc/kvm/../../../virt/kvm/vfio.o failed
make[3]: *** [arch/powerpc/kvm/../../../virt/kvm/vfio.o] Error 1
Check whether CONFIG_KVM_VFIO is set before including vfio.o
in the build.
Reported-by: Pranith Kumar <bobby.prani@gmail.com>
Tested-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The barrier also orders the write to mode from any reads
to the page tables done and so update the comment.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Upcoming in-kernel VFIO acceleration needs different handling in real
and virtual modes which makes it hard to support both modes in
the same handler.
This creates a copy of kvmppc_rm_h_stuff_tce and kvmppc_rm_h_put_tce
in addition to the existing kvmppc_rm_h_put_tce_indirect.
This also fixes linker breakage when only PR KVM was selected (leaving
HV KVM off): the kvmppc_h_put_tce/kvmppc_h_stuff_tce functions
would not compile at all and the linked would fail.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Highlights:
- Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras
- Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V
- Add POWER9 cputable entry from Michael Neuling
- FPU/Altivec/VSX save/restore optimisations from Cyril Bur
- Add support for new ftrace ABI on ppc64le from Torsten Duwe
Various cleanups & minor fixes from:
- Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril
Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey,
Sukadev Bhattiprolu, Suraj Jitindar Singh.
General:
- atomics: Allow architectures to define their own __atomic_op_* helpers from
Boqun Feng
- Implement atomic{, 64}_*_return_* variants and acquire/release/relaxed
variants for (cmp)xchg from Boqun Feng
- Add powernv_defconfig from Jeremy Kerr
- Fix BUG_ON() reporting in real mode from Balbir Singh
- Add xmon command to dump OPAL msglog from Andrew Donnellan
- Add xmon command to dump process/task similar to ps(1) from Douglas Miller
- Clean up memory hotplug failure paths from David Gibson
pci/eeh:
- Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei
Yang.
- EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
- PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
- PCI: Add pcibios_bus_add_device() weak function from Wei Yang
- MAINTAINERS: Update EEH details and maintainership from Russell Currey
cxl:
- Support added to the CXL driver for running on both bare-metal and
hypervisor systems, from Christophe Lombard and Frederic Barrat.
- Ignore probes for virtual afu pci devices from Vaibhav Jain
perf:
- Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu
- hv-24x7: Fix usage with chip events, display change in counter values,
display domain indices in sysfs, eliminate domain suffix in event names,
from Sukadev Bhattiprolu
Freescale:
- Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum
optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and
other dt bits, and minor fixes/cleanup."
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Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"This was delayed a day or two by some build-breakage on old toolchains
which we've now fixed.
There's two PCI commits both acked by Bjorn.
There's one commit to mm/hugepage.c which is (co)authored by Kirill.
Highlights:
- Restructure Linux PTE on Book3S/64 to Radix format from Paul
Mackerras
- Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh
Kumar K.V
- Add POWER9 cputable entry from Michael Neuling
- FPU/Altivec/VSX save/restore optimisations from Cyril Bur
- Add support for new ftrace ABI on ppc64le from Torsten Duwe
Various cleanups & minor fixes from:
- Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy,
Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell
Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh.
General:
- atomics: Allow architectures to define their own __atomic_op_*
helpers from Boqun Feng
- Implement atomic{, 64}_*_return_* variants and acquire/release/
relaxed variants for (cmp)xchg from Boqun Feng
- Add powernv_defconfig from Jeremy Kerr
- Fix BUG_ON() reporting in real mode from Balbir Singh
- Add xmon command to dump OPAL msglog from Andrew Donnellan
- Add xmon command to dump process/task similar to ps(1) from Douglas
Miller
- Clean up memory hotplug failure paths from David Gibson
pci/eeh:
- Redesign SR-IOV on PowerNV to give absolute isolation between VFs
from Wei Yang.
- EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
- PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
- PCI: Add pcibios_bus_add_device() weak function from Wei Yang
- MAINTAINERS: Update EEH details and maintainership from Russell
Currey
cxl:
- Support added to the CXL driver for running on both bare-metal and
hypervisor systems, from Christophe Lombard and Frederic Barrat.
- Ignore probes for virtual afu pci devices from Vaibhav Jain
perf:
- Export Power8 generic and cache events to sysfs from Sukadev
Bhattiprolu
- hv-24x7: Fix usage with chip events, display change in counter
values, display domain indices in sysfs, eliminate domain suffix in
event names, from Sukadev Bhattiprolu
Freescale:
- Updates from Scott: "Highlights include 8xx optimizations, 32-bit
checksum optimizations, 86xx consolidation, e5500/e6500 cpu
hotplug, more fman and other dt bits, and minor fixes/cleanup"
* tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
powerpc: Fix unrecoverable SLB miss during restore_math()
powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers
powerpc/rcpm: Fix build break when SMP=n
powerpc/book3e-64: Use hardcoded mttmr opcode
powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible
powerpc/T104xRDB: add tdm riser card node to device tree
powerpc32: PAGE_EXEC required for inittext
powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree
powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)
powerpc/86xx: Introduce and use common dtsi
powerpc/86xx: Update device tree
powerpc/86xx: Move dts files to fsl directory
powerpc/86xx: Switch to kconfig fragments approach
powerpc/86xx: Update defconfigs
powerpc/86xx: Consolidate common platform code
powerpc32: Remove one insn in mulhdu
powerpc32: small optimisation in flush_icache_range()
powerpc: Simplify test in __dma_sync()
powerpc32: move xxxxx_dcache_range() functions inline
powerpc32: Remove clear_pages() and define clear_page() inline
...
but lots of architecture-specific changes.
* ARM:
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- various optimizations to the vgic save/restore code.
* PPC:
- enabled KVM-VFIO integration ("VFIO device")
- optimizations to speed up IPIs between vcpus
- in-kernel handling of IOMMU hypercalls
- support for dynamic DMA windows (DDW).
* s390:
- provide the floating point registers via sync regs;
- separated instruction vs. data accesses
- dirty log improvements for huge guests
- bugfixes and documentation improvements.
* x86:
- Hyper-V VMBus hypercall userspace exit
- alternative implementation of lowest-priority interrupts using vector
hashing (for better VT-d posted interrupt support)
- fixed guest debugging with nested virtualizations
- improved interrupt tracking in the in-kernel IOAPIC
- generic infrastructure for tracking writes to guest memory---currently
its only use is to speedup the legacy shadow paging (pre-EPT) case, but
in the future it will be used for virtual GPUs as well
- much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"One of the largest releases for KVM... Hardly any generic
changes, but lots of architecture-specific updates.
ARM:
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- various optimizations to the vgic save/restore code.
PPC:
- enabled KVM-VFIO integration ("VFIO device")
- optimizations to speed up IPIs between vcpus
- in-kernel handling of IOMMU hypercalls
- support for dynamic DMA windows (DDW).
s390:
- provide the floating point registers via sync regs;
- separated instruction vs. data accesses
- dirty log improvements for huge guests
- bugfixes and documentation improvements.
x86:
- Hyper-V VMBus hypercall userspace exit
- alternative implementation of lowest-priority interrupts using
vector hashing (for better VT-d posted interrupt support)
- fixed guest debugging with nested virtualizations
- improved interrupt tracking in the in-kernel IOAPIC
- generic infrastructure for tracking writes to guest
memory - currently its only use is to speedup the legacy shadow
paging (pre-EPT) case, but in the future it will be used for
virtual GPUs as well
- much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
KVM: x86: disable MPX if host did not enable MPX XSAVE features
arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
arm64: KVM: vgic-v3: Reset LRs at boot time
arm64: KVM: vgic-v3: Do not save an LR known to be empty
arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
arm64: KVM: vgic-v3: Avoid accessing ICH registers
KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
KVM: arm/arm64: vgic-v2: Reset LRs at boot time
KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
KVM: s390: allocate only one DMA page per VM
KVM: s390: enable STFLE interpretation only if enabled for the guest
KVM: s390: wake up when the VCPU cpu timer expires
KVM: s390: step the VCPU timer while in enabled wait
KVM: s390: protect VCPU cpu timer with a seqcount
KVM: s390: step VCPU cpu timer during kvm_run ioctl
...
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle are:
- Make schedstats a runtime tunable (disabled by default) and
optimize it via static keys.
As most distributions enable CONFIG_SCHEDSTATS=y due to its
instrumentation value, this is a nice performance enhancement.
(Mel Gorman)
- Implement 'simple waitqueues' (swait): these are just pure
waitqueues without any of the more complex features of full-blown
waitqueues (callbacks, wake flags, wake keys, etc.). Simple
waitqueues have less memory overhead and are faster.
Use simple waitqueues in the RCU code (in 4 different places) and
for handling KVM vCPU wakeups.
(Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker,
Marcelo Tosatti)
- sched/numa enhancements (Rik van Riel)
- NOHZ performance enhancements (Rik van Riel)
- Various sched/deadline enhancements (Steven Rostedt)
- Various fixes (Peter Zijlstra)
- ... and a number of other fixes, cleanups and smaller enhancements"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
sched/cputime: Fix steal_account_process_tick() to always return jiffies
sched/deadline: Remove dl_new from struct sched_dl_entity
Revert "kbuild: Add option to turn incompatible pointer check into error"
sched/deadline: Remove superfluous call to switched_to_dl()
sched/debug: Fix preempt_disable_ip recording for preempt_disable()
sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity
time, acct: Drop irq save & restore from __acct_update_integrals()
acct, time: Change indentation in __acct_update_integrals()
sched, time: Remove non-power-of-two divides from __acct_update_integrals()
sched/rt: Kick RT bandwidth timer immediately on start up
sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug
sched/debug: Move sched_domain_sysctl to debug.c
sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
sched/rt: Fix PI handling vs. sched_setscheduler()
sched/core: Remove duplicated sched_group_set_shares() prototype
sched/fair: Consolidate nohz CPU load update code
sched/fair: Avoid using decay_load_missed() with a negative value
sched/deadline: Always calculate end of period on sched_yield()
sched/cgroup: Fix cgroup entity load tracking tear-down
rcu: Use simple wait queues where possible in rcutree
...
Thomas Huth discovered that a guest could cause a hard hang of a
host CPU by setting the Instruction Authority Mask Register (IAMR)
to a suitable value. It turns out that this is because when the
code was added to context-switch the new special-purpose registers
(SPRs) that were added in POWER8, we forgot to add code to ensure
that they were restored to a sane value on guest exit.
This adds code to set those registers where a bad value could
compromise the execution of the host kernel to a suitable neutral
value on guest exit.
Cc: stable@vger.kernel.org # v3.14+
Fixes: b005255e12
Reported-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The existing KVM_CREATE_SPAPR_TCE only supports 32bit windows which is not
enough for directly mapped windows as the guest can get more than 4GB.
This adds KVM_CREATE_SPAPR_TCE_64 ioctl and advertises it
via KVM_CAP_SPAPR_TCE_64 capability. The table size is checked against
the locked memory limit.
Since 64bit windows are to support Dynamic DMA windows (DDW), let's add
@bus_offset and @page_shift which are also required by DDW.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This enables userspace view of TCE tables to start from non-zero offset
on a bus. This will be used for huge DMA windows.
This only changes the internal structure, the user interface needs to
change in order to use an offset.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At the moment the kvmppc_spapr_tce_table struct can only describe
4GB windows and handle fixed size (4K) pages. Dynamic DMA windows
support more so these limits need to be extended.
This replaces window_size (in bytes, 4GB max) with page_shift (32bit)
and size (64bit, in pages).
This should cause no behavioural change as this is changing
the internal structures only - the user interface still only
allows one to create a 32-bit table with 4KiB pages at this stage.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Redirecting the wakeup of a VCPU from the H_IPI hypercall to
a core running in the host is usually a good idea, most workloads
seemed to benefit. However, in one heavily interrupt-driven SMT1
workload, some regression was observed. This patch adds a kvm_hv
module parameter called h_ipi_redirect to control this feature.
The default value for this tunable is 1 - that is enable the feature.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds support to real-mode KVM to search for a core
running in the host partition and send it an IPI message with
VCPU to be woken. This avoids having to switch to the host
partition to complete an H_IPI hypercall when the VCPU which
is the target of the the H_IPI is not loaded (is not running
in the guest).
The patch also includes the support in the IPI handler running
in the host to do the wakeup by calling kvmppc_xics_ipi_action
for the PPC_MSG_RM_HOST_ACTION message.
When a guest is being destroyed, we need to ensure that there
are no pending IPIs waiting to wake up a VCPU before we free
the VCPUs of the guest. This is accomplished by:
- Forces a PPC_MSG_CALL_FUNCTION IPI to be completed by all CPUs
before freeing any VCPUs in kvm_arch_destroy_vm().
- Any PPC_MSG_RM_HOST_ACTION messages must be executed first
before any other PPC_MSG_CALL_FUNCTION messages.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds the support for the kick VCPU operation for
kvmppc_host_rm_ops. The kvmppc_xics_ipi_action() function
provides the function to be invoked for a host side operation
when poked by the real mode KVM. This is initiated by KVM by
sending an IPI to any free host core.
KVM real mode must set the rm_action to XICS_RM_KICK_VCPU and
rm_data to point to the VCPU to be woken up before sending the IPI.
Note that we have allocated one kvmppc_host_rm_core structure
per core. The above values need to be set in the structure
corresponding to the core to which the IPI will be sent.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The kvmppc_host_rm_ops structure keeps track of which cores are
are in the host by maintaining a bitmask of active/runnable
online CPUs that have not entered the guest. This patch adds
support to manage the bitmask when a CPU is offlined or onlined
in the host.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Update the core host state in kvmppc_host_rm_ops whenever
the primary thread of the core enters the guest or returns
back.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch defines the data structures to support the setting up
of host side operations while running in real mode in the guest,
and also the functions to allocate and free it.
The operations are for now limited to virtual XICS operations.
Currently, we have only defined one operation in the data
structure:
- Wake up a VCPU sleeping in the host when it
receives a virtual interrupt
The operations are assigned at the core level because PowerKVM
requires that the host run in SMT off mode. For each core,
we will need to manage its state atomically - where the state
is defined by:
1. Is the core running in the host?
2. Is there a Real Mode (RM) operation pending on the host?
Currently, core state is only managed at the whole-core level
even when the system is in split-core mode. This just limits
the number of free or "available" cores in the host to perform
any host-side operations.
The kvmppc_host_rm_core.rm_data allows any data to be passed by
KVM in real mode to the host core along with the operation to
be performed.
The kvmppc_host_rm_ops structure is allocated the very first time
a guest VM is started. Initial core state is also set - all online
cores are in the host. This structure is never deleted, not even
when there are no active guests. However, it needs to be freed
when the module is unloaded because the kvmppc_host_rm_ops_hv
can contain function pointers to kvm-hv.ko functions for the
different supported host operations.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The problem:
On -rt, an emulated LAPIC timer instances has the following path:
1) hard interrupt
2) ksoftirqd is scheduled
3) ksoftirqd wakes up vcpu thread
4) vcpu thread is scheduled
This extra context switch introduces unnecessary latency in the
LAPIC path for a KVM guest.
The solution:
Allow waking up vcpu thread from hardirq context,
thus avoiding the need for ksoftirqd to be scheduled.
Normal waitqueues make use of spinlocks, which on -RT
are sleepable locks. Therefore, waking up a waitqueue
waiter involves locking a sleeping lock, which
is not allowed from hard interrupt context.
cyclictest command line:
This patch reduces the average latency in my tests from 14us to 11us.
Daniel writes:
Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency
benchmark on mainline. The test was run 1000 times on
tip/sched/core 4.4.0-rc8-01134-g0905f04:
./x86-run x86/tscdeadline_latency.flat -cpu host
with idle=poll.
The test seems not to deliver really stable numbers though most of
them are smaller. Paolo write:
"Anything above ~10000 cycles means that the host went to C1 or
lower---the number means more or less nothing in that case.
The mean shows an improvement indeed."
Before:
min max mean std
count 1000.000000 1000.000000 1000.000000 1000.000000
mean 5162.596000 2019270.084000 5824.491541 20681.645558
std 75.431231 622607.723969 89.575700 6492.272062
min 4466.000000 23928.000000 5537.926500 585.864966
25% 5163.000000 1613252.750000 5790.132275 16683.745433
50% 5175.000000 2281919.000000 5834.654000 23151.990026
75% 5190.000000 2382865.750000 5861.412950 24148.206168
max 5228.000000 4175158.000000 6254.827300 46481.048691
After
min max mean std
count 1000.000000 1000.00000 1000.000000 1000.000000
mean 5143.511000 2076886.10300 5813.312474 21207.357565
std 77.668322 610413.09583 86.541500 6331.915127
min 4427.000000 25103.00000 5529.756600 559.187707
25% 5148.000000 1691272.75000 5784.889825 17473.518244
50% 5160.000000 2308328.50000 5832.025000 23464.837068
75% 5172.000000 2393037.75000 5853.177675 24223.969976
max 5222.000000 3922458.00000 6186.720500 42520.379830
[Patch was originaly based on the swait implementation found in the -rt
tree. Daniel ported it to mainline's version and gathered the
benchmark numbers for tscdeadline_latency test.]
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-rt-users@vger.kernel.org
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This adds real and virtual mode handlers for the H_PUT_TCE_INDIRECT and
H_STUFF_TCE hypercalls for user space emulated devices such as IBMVIO
devices or emulated PCI. These calls allow adding multiple entries
(up to 512) into the TCE table in one call which saves time on
transition between kernel and user space.
The current implementation of kvmppc_h_stuff_tce() allows it to be
executed in both real and virtual modes so there is one helper.
The kvmppc_rm_h_put_tce_indirect() needs to translate the guest address
to the host address and since the translation is different, there are
2 helpers - one for each mode.
This implements the KVM_CAP_PPC_MULTITCE capability. When present,
the kernel will try handling H_PUT_TCE_INDIRECT and H_STUFF_TCE if these
are enabled by the userspace via KVM_CAP_PPC_ENABLE_HCALL.
If they can not be handled by the kernel, they are passed on to
the user space. The user space still has to have an implementation
for these.
Both HV and PR-syle KVM are supported.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Upcoming multi-tce support (H_PUT_TCE_INDIRECT/H_STUFF_TCE hypercalls)
will validate TCE (not to have unexpected bits) and IO address
(to be within the DMA window boundaries).
This introduces helpers to validate TCE and IO address. The helpers are
exported as they compile into vmlinux (to work in realmode) and will be
used later by KVM kernel module in virtual mode.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
SPAPR_TCE_SHIFT is used in few places only and since IOMMU_PAGE_SHIFT_4K
can be easily used instead, remove SPAPR_TCE_SHIFT.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At the moment pages used for TCE tables (in addition to pages addressed
by TCEs) are not counted in locked_vm counter so a malicious userspace
tool can call ioctl(KVM_CREATE_SPAPR_TCE) as many times as
RLIMIT_NOFILE and lock a lot of memory.
This adds counting for pages used for TCE tables.
This counts the number of pages required for a table plus pages for
the kvmppc_spapr_tce_table struct (TCE table descriptor) itself.
This changes release_spapr_tce_table() to store @npages on stack to
avoid calling kvmppc_stt_npages() in the loop (tiny optimization,
probably).
This does not change the amount of used memory.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
At the moment only spapr_tce_tables updates are protected against races
but not lookups. This fixes missing protection by using RCU for the list.
As lookups also happen in real mode, this uses
list_for_each_entry_lockless() (which is expected not to access any
vmalloc'd memory).
This converts release_spapr_tce_table() to a RCU scheduled handler.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This reworks the existing H_PUT_TCE/H_GET_TCE handlers to have following
patches applied nicer.
This moves the ioba boundaries check to a helper and adds a check for
least bits which have to be zeros.
The patch is pretty mechanical (only check for least ioba bits is added)
so no change in behaviour is expected.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
ec53500f "kvm: Add VFIO device" added a special KVM pseudo-device which is
used to handle any necessary interactions between KVM and VFIO.
Currently that device is built on x86 and ARM, but not powerpc, although
powerpc does support both KVM and VFIO. This makes things awkward in
userspace
Currently qemu prints an alarming error message if you attempt to use VFIO
and it can't initialize the KVM VFIO device. We don't want to remove the
warning, because lack of the KVM VFIO device could mean coherency problems
on x86. On powerpc, however, the error is harmless but looks disturbing,
and a test based on host architecture in qemu would be ugly, and break if
we do need the KVM VFIO device for something important in future.
There's nothing preventing the KVM VFIO device from being built for
powerpc, so this patch turns it on. It won't actually do anything, since
we don't define any of the arch_*() hooks, but it will make qemu happy and
we can extend it in future if we need to.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
To date, we have implemented two I/O usage models for persistent memory,
PMEM (a persistent "ram disk") and DAX (mmap persistent memory into
userspace). This series adds a third, DAX-GUP, that allows DAX mappings
to be the target of direct-i/o. It allows userspace to coordinate
DMA/RDMA from/to persistent memory.
The implementation leverages the ZONE_DEVICE mm-zone that went into
4.3-rc1 (also discussed at kernel summit) to flag pages that are owned
and dynamically mapped by a device driver. The pmem driver, after
mapping a persistent memory range into the system memmap via
devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus
page-backed pmem-pfns via flags in the new pfn_t type.
The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the
resulting pte(s) inserted into the process page tables with a new
_PAGE_DEVMAP flag. Later, when get_user_pages() is walking ptes it keys
off _PAGE_DEVMAP to pin the device hosting the page range active.
Finally, get_page() and put_page() are modified to take references
against the device driver established page mapping.
Finally, this need for "struct page" for persistent memory requires
memory capacity to store the memmap array. Given the memmap array for a
large pool of persistent may exhaust available DRAM introduce a
mechanism to allocate the memmap from persistent memory. The new
"struct vmem_altmap *" parameter to devm_memremap_pages() enables
arch_add_memory() to use reserved pmem capacity rather than the page
allocator.
This patch (of 18):
The core has developed a need for a "pfn_t" type [1]. Move the existing
pfn_t in KVM to kvm_pfn_t [2].
[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html
[2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Ground work for the new Power9 MMU from Aneesh Kumar K.V
- Optimise FP/VMX/VSX context switching from Anton Blanchard
- Various cleanups from Krzysztof Kozlowski, John Ogness, Rashmica Gupta,
Russell Currey, Gavin Shan, Daniel Axtens, Michael Neuling, Andrew Donnellan
- Allow wrapper to work on non-english system from Laurent Vivier
- Add rN aliases to the pt_regs_offset table from Rashmica Gupta
- Fix module autoload for rackmeter & axonram drivers from Luis de Bethencourt
- Include KVM guest test in all interrupt vectors from Paul Mackerras
- Fix DSCR inheritance over fork() from Anton Blanchard
- Make value-returning atomics & {cmp}xchg* & their atomic_ versions fully ordered from Boqun Feng
- Print MSR TM bits in oops messages from Michael Neuling
- Add TM signal return & invalid stack selftests from Michael Neuling
- Limit EPOW reset event warnings from Vipin K Parashar
- Remove the Cell QPACE code from Rashmica Gupta
- Append linux_banner to exception information in xmon from Rashmica Gupta
- Add selftest to check if VSRs are corrupted from Rashmica Gupta
- Remove broken GregorianDay() from Daniel Axtens
- Import Anton's context_switch2 benchmark into selftests from Michael Ellerman
- Add selftest script to test HMI functionality from Daniel Axtens
- Remove obsolete OPAL v2 support from Stewart Smith
- Make enter_rtas() private from Michael Ellerman
- PPR exception cleanups from Michael Ellerman
- Add page soft dirty tracking from Laurent Dufour
- Add support for Nvlink NPUs from Alistair Popple
- Add support for kexec on 476fpe from Alistair Popple
- Enable kernel CPU dlpar from sysfs from Nathan Fontenot
- Copy only required pieces of the mm_context_t to the paca from Michael Neuling
- Add a kmsg_dumper that flushes OPAL console output on panic from Russell Currey
- Implement save_stack_trace_regs() to enable kprobe stack tracing from Steven Rostedt
- Add HWCAP bits for Power9 from Michael Ellerman
- Fix _PAGE_PTE breaking swapoff from Aneesh Kumar K.V
- Fix _PAGE_SWP_SOFT_DIRTY breaking swapoff from Hugh Dickins
- scripts/recordmcount.pl: support data in text section on powerpc from Ulrich Weigand
- Handle R_PPC64_ENTRY relocations in modules from Ulrich Weigand
- cxl: Fix possible idr warning when contexts are released from Vaibhav Jain
- cxl: use correct operator when writing pcie config space values from Andrew Donnellan
- cxl: Fix DSI misses when the context owning task exits from Vaibhav Jain
- cxl: fix build for GCC 4.6.x from Brian Norris
- cxl: use -Werror only with CONFIG_PPC_WERROR from Brian Norris
- cxl: Enable PCI device ID for future IBM CXL adapter from Uma Krishnan
- Freescale updates from Scott: Highlights include moving QE code out of
arch/powerpc (to be shared with arm), device tree updates, and minor fixes.
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Merge tag 'powerpc-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Core:
- Ground work for the new Power9 MMU from Aneesh Kumar K.V
- Optimise FP/VMX/VSX context switching from Anton Blanchard
Misc:
- Various cleanups from Krzysztof Kozlowski, John Ogness, Rashmica
Gupta, Russell Currey, Gavin Shan, Daniel Axtens, Michael Neuling,
Andrew Donnellan
- Allow wrapper to work on non-english system from Laurent Vivier
- Add rN aliases to the pt_regs_offset table from Rashmica Gupta
- Fix module autoload for rackmeter & axonram drivers from Luis de
Bethencourt
- Include KVM guest test in all interrupt vectors from Paul Mackerras
- Fix DSCR inheritance over fork() from Anton Blanchard
- Make value-returning atomics & {cmp}xchg* & their atomic_ versions
fully ordered from Boqun Feng
- Print MSR TM bits in oops messages from Michael Neuling
- Add TM signal return & invalid stack selftests from Michael Neuling
- Limit EPOW reset event warnings from Vipin K Parashar
- Remove the Cell QPACE code from Rashmica Gupta
- Append linux_banner to exception information in xmon from Rashmica
Gupta
- Add selftest to check if VSRs are corrupted from Rashmica Gupta
- Remove broken GregorianDay() from Daniel Axtens
- Import Anton's context_switch2 benchmark into selftests from
Michael Ellerman
- Add selftest script to test HMI functionality from Daniel Axtens
- Remove obsolete OPAL v2 support from Stewart Smith
- Make enter_rtas() private from Michael Ellerman
- PPR exception cleanups from Michael Ellerman
- Add page soft dirty tracking from Laurent Dufour
- Add support for Nvlink NPUs from Alistair Popple
- Add support for kexec on 476fpe from Alistair Popple
- Enable kernel CPU dlpar from sysfs from Nathan Fontenot
- Copy only required pieces of the mm_context_t to the paca from
Michael Neuling
- Add a kmsg_dumper that flushes OPAL console output on panic from
Russell Currey
- Implement save_stack_trace_regs() to enable kprobe stack tracing
from Steven Rostedt
- Add HWCAP bits for Power9 from Michael Ellerman
- Fix _PAGE_PTE breaking swapoff from Aneesh Kumar K.V
- Fix _PAGE_SWP_SOFT_DIRTY breaking swapoff from Hugh Dickins
- scripts/recordmcount.pl: support data in text section on powerpc
from Ulrich Weigand
- Handle R_PPC64_ENTRY relocations in modules from Ulrich Weigand
cxl:
- cxl: Fix possible idr warning when contexts are released from
Vaibhav Jain
- cxl: use correct operator when writing pcie config space values
from Andrew Donnellan
- cxl: Fix DSI misses when the context owning task exits from Vaibhav
Jain
- cxl: fix build for GCC 4.6.x from Brian Norris
- cxl: use -Werror only with CONFIG_PPC_WERROR from Brian Norris
- cxl: Enable PCI device ID for future IBM CXL adapter from Uma
Krishnan
Freescale:
- Freescale updates from Scott: Highlights include moving QE code out
of arch/powerpc (to be shared with arm), device tree updates, and
minor fixes"
* tag 'powerpc-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (149 commits)
powerpc/module: Handle R_PPC64_ENTRY relocations
scripts/recordmcount.pl: support data in text section on powerpc
powerpc/powernv: Fix OPAL_CONSOLE_FLUSH prototype and usages
powerpc/mm: fix _PAGE_SWP_SOFT_DIRTY breaking swapoff
powerpc/mm: Fix _PAGE_PTE breaking swapoff
cxl: Enable PCI device ID for future IBM CXL adapter
cxl: use -Werror only with CONFIG_PPC_WERROR
cxl: fix build for GCC 4.6.x
powerpc: Add HWCAP bits for Power9
powerpc/powernv: Reserve PE#0 on NPU
powerpc/powernv: Change NPU PE# assignment
powerpc/powernv: Fix update of NVLink DMA mask
powerpc/powernv: Remove misleading comment in pci.c
powerpc: Implement save_stack_trace_regs() to enable kprobe stack tracing
powerpc: Fix build break due to paca mm_context_t changes
cxl: Fix DSI misses when the context owning task exits
MAINTAINERS: Update Scott Wood's e-mail address
powerpc/powernv: Fix minor off-by-one error in opal_mce_check_early_recovery()
powerpc: Fix style of self-test config prompts
powerpc/powernv: Only delay opal_rtc_read() retry when necessary
...
The get and set operations got exchanged by mistake when moving the
code from book3s.c to powerpc.c.
Fixes: 3840edc803
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
support of 248 VCPUs.
* ARM: rewrite of the arm64 world switch in C, support for
16-bit VM identifiers. Performance counter virtualization
missed the boat.
* x86: Support for more Hyper-V features (synthetic interrupt
controller), MMU cleanups
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"PPC changes will come next week.
- s390: Support for runtime instrumentation within guests, support of
248 VCPUs.
- ARM: rewrite of the arm64 world switch in C, support for 16-bit VM
identifiers. Performance counter virtualization missed the boat.
- x86: Support for more Hyper-V features (synthetic interrupt
controller), MMU cleanups"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (115 commits)
kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
kvm/x86: Hyper-V SynIC timers tracepoints
kvm/x86: Hyper-V SynIC tracepoints
kvm/x86: Update SynIC timers on guest entry only
kvm/x86: Skip SynIC vector check for QEMU side
kvm/x86: Hyper-V fix SynIC timer disabling condition
kvm/x86: Reorg stimer_expiration() to better control timer restart
kvm/x86: Hyper-V unify stimer_start() and stimer_restart()
kvm/x86: Drop stimer_stop() function
kvm/x86: Hyper-V timers fix incorrect logical operation
KVM: move architecture-dependent requests to arch/
KVM: renumber vcpu->request bits
KVM: document which architecture uses each request bit
KVM: Remove unused KVM_REQ_KICK to save a bit in vcpu->requests
kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock
KVM: s390: implement the RI support of guest
kvm/s390: drop unpaired smp_mb
kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa
KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()
arm/arm64: KVM: Detect vGIC presence at runtime
...
Currently it is possible for userspace (e.g. QEMU) to set a value
for the MSR for a guest VCPU which has both of the TS bits set,
which is an illegal combination. The result of this is that when
we execute a hrfid (hypervisor return from interrupt doubleword)
instruction to enter the guest, the CPU will take a TM Bad Thing
type of program interrupt (vector 0x700).
Now, if PR KVM is configured in the kernel along with HV KVM, we
actually handle this without crashing the host or giving hypervisor
privilege to the guest; instead what happens is that we deliver a
program interrupt to the guest, with SRR0 reflecting the address
of the hrfid instruction and SRR1 containing the MSR value at that
point. If PR KVM is not configured in the kernel, then we try to
run the host's program interrupt handler with the MMU set to the
guest context, which almost certainly causes a host crash.
This closes the hole by making kvmppc_set_msr_hv() check for the
illegal combination and force the TS field to a safe value (00,
meaning non-transactional).
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Paul Mackerras <paulus@samba.org>
The vcpu_book3s variable is assigned but never used. So remove it.
Found using cppcheck.
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In the old DABR register, the BT (Breakpoint Translation) bit
is bit number 61. In the new DAWRX register, the WT (Watchpoint
Translation) bit is bit number 59. So to move the DABR-BT bit
into the position of the DAWRX-WT bit, it has to be shifted by
two, not only by one. This fixes hardware watchpoints in gdb of
older guests that only use the H_SET_DABR/X interface instead
of the new H_SET_MODE interface.
Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
As we saw with the TM Bad Thing type of program interrupt occurring
on the hrfid that enters the guest, it is not completely impossible
to have a trap occurring in the guest entry/exit code, despite the
fact that the code has been written to avoid taking any traps.
This adds a check in the kvmppc_handle_exit_hv() function to detect
the case when a trap has occurred in the hypervisor-mode code, and
instead of treating it just like a trap in guest code, we now print
a message and return to userspace with a KVM_EXIT_INTERNAL_ERROR
exit reason.
Of the various interrupts that get handled in the assembly code in
the guest exit path and that can return directly to the guest, the
only one that can occur when MSR.HV=1 and MSR.EE=0 is machine check
(other than system call, which we can avoid just by not doing a sc
instruction). Therefore this adds code to the machine check path to
ensure that if the MCE occurred in hypervisor mode, we exit to the
host rather than trying to continue the guest.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Create a single function that flushes everything (FP, VMX, VSX, SPE).
Doing this all at once means we only do one MSR write.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Create a single function that gives everything up (FP, VMX, VSX, SPE).
Doing this all at once means we only do one MSR write.
A context switch microbenchmark using yield():
http://ozlabs.org/~anton/junkcode/context_switch2.c
./context_switch2 --test=yield --fp --altivec --vector 0 0
shows an improvement of 3% on POWER8.
Signed-off-by: Anton Blanchard <anton@samba.org>
[mpe: giveup_all() needs to be EXPORT_SYMBOL'ed]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The enable_kernel_*() functions leave the relevant MSR bits enabled
until we exit the kernel sometime later. Create disable versions
that wrap the kernel use of FP, Altivec VSX or SPE.
While we don't want to disable it normally for performance reasons
(MSR writes are slow), it will be used for a debug boot option that
does this and catches bad uses in other areas of the kernel.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Let's reuse the new common function for VPCU lookup by id.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[split out the new function into a separate patch]
In another patch kvm_is_visible_gfn is maken return bool due to this
function only returns zero or one as its return value, let's also make
kvmppc_visible_gpa return bool to keep consistent.
No functional change.
Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- x86: work around two nasty cases where a benign exception occurs while
another is being delivered. The endless stream of exceptions causes an
infinite loop in the processor, which not even NMIs or SMIs can interrupt;
in the virt case, there is no possibility to exit to the host either.
- x86: support for Skylake per-guest TSC rate. Long supported by AMD,
the patches mostly move things from there to common arch/x86/kvm/ code.
- generic: remove local_irq_save/restore from the guest entry and exit
paths when context tracking is enabled. The patches are a few months
old, but we discussed them again at kernel summit. Andy will pick up
from here and, in 4.5, try to remove it from the user entry/exit paths.
- PPC: Two bug fixes, see merge commit 370289756b for details.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull second batch of kvm updates from Paolo Bonzini:
"Four changes:
- x86: work around two nasty cases where a benign exception occurs
while another is being delivered. The endless stream of exceptions
causes an infinite loop in the processor, which not even NMIs or
SMIs can interrupt; in the virt case, there is no possibility to
exit to the host either.
- x86: support for Skylake per-guest TSC rate. Long supported by
AMD, the patches mostly move things from there to common
arch/x86/kvm/ code.
- generic: remove local_irq_save/restore from the guest entry and
exit paths when context tracking is enabled. The patches are a few
months old, but we discussed them again at kernel summit. Andy
will pick up from here and, in 4.5, try to remove it from the user
entry/exit paths.
- PPC: Two bug fixes, see merge commit 370289756b for details"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (21 commits)
KVM: x86: rename update_db_bp_intercept to update_bp_intercept
KVM: svm: unconditionally intercept #DB
KVM: x86: work around infinite loop in microcode when #AC is delivered
context_tracking: avoid irq_save/irq_restore on guest entry and exit
context_tracking: remove duplicate enabled check
KVM: VMX: Dump TSC multiplier in dump_vmcs()
KVM: VMX: Use a scaled host TSC for guest readings of MSR_IA32_TSC
KVM: VMX: Setup TSC scaling ratio when a vcpu is loaded
KVM: VMX: Enable and initialize VMX TSC scaling
KVM: x86: Use the correct vcpu's TSC rate to compute time scale
KVM: x86: Move TSC scaling logic out of call-back read_l1_tsc()
KVM: x86: Move TSC scaling logic out of call-back adjust_tsc_offset()
KVM: x86: Replace call-back compute_tsc_offset() with a common function
KVM: x86: Replace call-back set_tsc_khz() with a common function
KVM: x86: Add a common TSC scaling function
KVM: x86: Add a common TSC scaling ratio field in kvm_vcpu_arch
KVM: x86: Collect information for setting TSC scaling ratio
KVM: x86: declare a few variables as __read_mostly
KVM: x86: merge handle_mmio_page_fault and handle_mmio_page_fault_common
KVM: PPC: Book3S HV: Don't dynamically split core when already split
...
- Kconfig: remove BE-only platforms from LE kernel build from Boqun Feng
- Refresh ps3_defconfig from Geoff Levand
- Emit GNU & SysV hashes for the vdso from Michael Ellerman
- Define an enum for the bolted SLB indexes from Anshuman Khandual
- Use a local to avoid multiple calls to get_slb_shadow() from Michael Ellerman
- Add gettimeofday() benchmark from Michael Neuling
- Avoid link stack corruption in __get_datapage() from Michael Neuling
- Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar K.V
- Add ppc64le_defconfig from Michael Ellerman
- pseries: extract of_helpers module from Andy Shevchenko
- Correct string length in pseries_of_derive_parent() from Nathan Fontenot
- Free the MSI bitmap if it was slab allocated from Denis Kirjanov
- Shorten irq_chip name for the SIU from Christophe Leroy
- Wait 1s for secondaries to enter OPAL during kexec from Samuel Mendoza-Jonas
- Fix _ALIGN_* errors due to type difference. from Aneesh Kumar K.V
- powerpc/pseries/hvcserver: don't memset pi_buff if it is null from Colin Ian King
- Disable hugepd for 64K page size. from Aneesh Kumar K.V
- Differentiate between hugetlb and THP during page walk from Aneesh Kumar K.V
- Make PCI non-optional for pseries from Michael Ellerman
- Individual System V IPC system calls from Sam bobroff
- Add selftest of unmuxed IPC calls from Michael Ellerman
- discard .exit.data at runtime from Stephen Rothwell
- Delete old orphaned PrPMC 280/2800 DTS and boot file. from Paul Gortmaker
- Use of_get_next_parent to simplify code from Christophe Jaillet
- Paginate some xmon output from Sam bobroff
- Add some more elements to the xmon PACA dump from Michael Ellerman
- Allow the tm-syscall selftest to build with old headers from Michael Ellerman
- Run EBB selftests only on POWER8 from Denis Kirjanov
- Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael Ellerman
- Avoid reference to potentially freed memory in prom.c from Christophe Jaillet
- Quieten boot wrapper output with run_cmd from Geoff Levand
- EEH fixes and cleanups from Gavin Shan
- Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
- Use of_get_next_parent() in of_get_ibm_chip_id() from Michael Ellerman
- Fix section mismatch warning in msi_bitmap_alloc() from Denis Kirjanov
- Fix ps3-lpm white space from Rudhresh Kumar J
- Fix ps3-vuart null dereference from Colin King
- nvram: Add missing kfree in error path from Christophe Jaillet
- nvram: Fix function name in some errors messages. from Christophe Jaillet
- drivers/macintosh: adb: fix misleading Kconfig help text from Aaro Koskinen
- agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
- cxl: Free virtual PHB when removing from Andrew Donnellan
- scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from Michael Ellerman
- scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building with O= from Michael Ellerman
- Freescale updates from Scott: Highlights include 64-bit book3e kexec/kdump
support, a rework of the qoriq clock driver, device tree changes including
qoriq fman nodes, support for a new 85xx board, and some fixes.
- MPC5xxx updates from Anatolij: Highlights include a driver for MPC512x
LocalPlus Bus FIFO with its device tree binding documentation, mpc512x
device tree updates and some minor fixes.
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Merge tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Kconfig: remove BE-only platforms from LE kernel build from Boqun
Feng
- Refresh ps3_defconfig from Geoff Levand
- Emit GNU & SysV hashes for the vdso from Michael Ellerman
- Define an enum for the bolted SLB indexes from Anshuman Khandual
- Use a local to avoid multiple calls to get_slb_shadow() from Michael
Ellerman
- Add gettimeofday() benchmark from Michael Neuling
- Avoid link stack corruption in __get_datapage() from Michael Neuling
- Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar
K.V
- Add ppc64le_defconfig from Michael Ellerman
- pseries: extract of_helpers module from Andy Shevchenko
- Correct string length in pseries_of_derive_parent() from Nathan
Fontenot
- Free the MSI bitmap if it was slab allocated from Denis Kirjanov
- Shorten irq_chip name for the SIU from Christophe Leroy
- Wait 1s for secondaries to enter OPAL during kexec from Samuel
Mendoza-Jonas
- Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V
- powerpc/pseries/hvcserver: don't memset pi_buff if it is null from
Colin Ian King
- Disable hugepd for 64K page size, from Aneesh Kumar K.V
- Differentiate between hugetlb and THP during page walk from Aneesh
Kumar K.V
- Make PCI non-optional for pseries from Michael Ellerman
- Individual System V IPC system calls from Sam bobroff
- Add selftest of unmuxed IPC calls from Michael Ellerman
- discard .exit.data at runtime from Stephen Rothwell
- Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul
Gortmaker
- Use of_get_next_parent to simplify code from Christophe Jaillet
- Paginate some xmon output from Sam bobroff
- Add some more elements to the xmon PACA dump from Michael Ellerman
- Allow the tm-syscall selftest to build with old headers from Michael
Ellerman
- Run EBB selftests only on POWER8 from Denis Kirjanov
- Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael
Ellerman
- Avoid reference to potentially freed memory in prom.c from Christophe
Jaillet
- Quieten boot wrapper output with run_cmd from Geoff Levand
- EEH fixes and cleanups from Gavin Shan
- Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
- Use of_get_next_parent() in of_get_ibm_chip_id() from Michael
Ellerman
- Fix section mismatch warning in msi_bitmap_alloc() from Denis
Kirjanov
- Fix ps3-lpm white space from Rudhresh Kumar J
- Fix ps3-vuart null dereference from Colin King
- nvram: Add missing kfree in error path from Christophe Jaillet
- nvram: Fix function name in some errors messages, from Christophe
Jaillet
- drivers/macintosh: adb: fix misleading Kconfig help text from Aaro
Koskinen
- agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
- cxl: Free virtual PHB when removing from Andrew Donnellan
- scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from
Michael Ellerman
- scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building
with O= from Michael Ellerman
- Freescale updates from Scott: Highlights include 64-bit book3e
kexec/kdump support, a rework of the qoriq clock driver, device tree
changes including qoriq fman nodes, support for a new 85xx board, and
some fixes.
- MPC5xxx updates from Anatolij: Highlights include a driver for
MPC512x LocalPlus Bus FIFO with its device tree binding
documentation, mpc512x device tree updates and some minor fixes.
* tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits)
powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc()
powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id()
powerpc/pseries: Correct string length in pseries_of_derive_parent()
powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry
powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s)
powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan
powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes
powerpc: handle error case in cpm_muram_alloc()
powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake
powerpc/book3e-64: Enable kexec
powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop
powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32
powerpc/book3e-64/kexec: Enable SMP release
powerpc/book3e-64/kexec: create an identity TLB mapping
powerpc/book3e-64: Don't limit paca to 256 MiB
powerpc/book3e/kdump: Enable crash_kexec_wait_realmode
powerpc/book3e: support CONFIG_RELOCATABLE
powerpc/booke64: Fix args to copy_and_flush
powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts
powerpc/e6500: kexec: Handle hardware threads
...
In static micro-threading modes, the dynamic micro-threading code
is supposed to be disabled, because subcores can't make independent
decisions about what micro-threading mode to put the core in - there is
only one micro-threading mode for the whole core. The code that
implements dynamic micro-threading checks for this, except that the
check was missed in one case. This means that it is possible for a
subcore in static 2-way micro-threading mode to try to put the core
into 4-way micro-threading mode, which usually leads to stuck CPUs,
spinlock lockups, and other stalls in the host.
The problem was in the can_split_piggybacked_subcores() function, which
should always return false if the system is in a static micro-threading
mode. This fixes the problem by making can_split_piggybacked_subcores()
use subcore_config_ok() for its checks, as subcore_config_ok() includes
the necessary check for the static micro-threading modes.
Credit to Gautham Shenoy for working out that the reason for the hangs
and stalls we were seeing was that we were trying to do dynamic 4-way
micro-threading while we were in static 2-way mode.
Fixes: b4deba5c41
Cc: vger@stable.kernel.org # v4.3
Signed-off-by: Paul Mackerras <paulus@samba.org>
When handling a hypervisor data or instruction storage interrupt (HDSI
or HISI), we look up the SLB entry for the address being accessed in
order to translate the effective address to a virtual address which can
be looked up in the guest HPT. This lookup can occasionally fail due
to the guest replacing an SLB entry without invalidating the evicted
SLB entry. In this situation an ERAT (effective to real address
translation cache) entry can persist and be used by the hardware even
though there is no longer a corresponding SLB entry.
Previously we would just deliver a data or instruction storage interrupt
(DSI or ISI) to the guest in this case. However, this is not correct
and has been observed to cause guests to crash, typically with a
data storage protection interrupt on a store to the vmemmap area.
Instead, what we do now is to synthesize a data or instruction segment
interrupt. That should cause the guest to reload an appropriate entry
into the SLB and retry the faulting instruction. If it still faults,
we should find an appropriate SLB entry next time and be able to handle
the fault.
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
handling.
PPC: Mostly bug fixes.
ARM: No big features, but many small fixes and prerequisites including:
- a number of fixes for the arch-timer
- introducing proper level-triggered semantics for the arch-timers
- a series of patches to synchronously halt a guest (prerequisite for
IRQ forwarding)
- some tracepoint improvements
- a tweak for the EL2 panic handlers
- some more VGIC cleanups getting rid of redundant state
x86: quite a few changes:
- support for VT-d posted interrupts (i.e. PCI devices can inject
interrupts directly into vCPUs). This introduces a new component (in
virt/lib/) that connects VFIO and KVM together. The same infrastructure
will be used for ARM interrupt forwarding as well.
- more Hyper-V features, though the main one Hyper-V synthetic interrupt
controller will have to wait for 4.5. These will let KVM expose Hyper-V
devices.
- nested virtualization now supports VPID (same as PCID but for vCPUs)
which makes it quite a bit faster
- for future hardware that supports NVDIMM, there is support for clflushopt,
clwb, pcommit
- support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
userspace, which reduces the attack surface of the hypervisor
- obligatory smattering of SMM fixes
- on the guest side, stable scheduler clock support was rewritten to not
require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"First batch of KVM changes for 4.4.
s390:
A bunch of fixes and optimizations for interrupt and time handling.
PPC:
Mostly bug fixes.
ARM:
No big features, but many small fixes and prerequisites including:
- a number of fixes for the arch-timer
- introducing proper level-triggered semantics for the arch-timers
- a series of patches to synchronously halt a guest (prerequisite
for IRQ forwarding)
- some tracepoint improvements
- a tweak for the EL2 panic handlers
- some more VGIC cleanups getting rid of redundant state
x86:
Quite a few changes:
- support for VT-d posted interrupts (i.e. PCI devices can inject
interrupts directly into vCPUs). This introduces a new
component (in virt/lib/) that connects VFIO and KVM together.
The same infrastructure will be used for ARM interrupt
forwarding as well.
- more Hyper-V features, though the main one Hyper-V synthetic
interrupt controller will have to wait for 4.5. These will let
KVM expose Hyper-V devices.
- nested virtualization now supports VPID (same as PCID but for
vCPUs) which makes it quite a bit faster
- for future hardware that supports NVDIMM, there is support for
clflushopt, clwb, pcommit
- support for "split irqchip", i.e. LAPIC in kernel +
IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
the hypervisor
- obligatory smattering of SMM fixes
- on the guest side, stable scheduler clock support was rewritten
to not require help from the hypervisor"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
KVM: VMX: Fix commit which broke PML
KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
KVM: x86: allow RSM from 64-bit mode
KVM: VMX: fix SMEP and SMAP without EPT
KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
KVM: device assignment: remove pointless #ifdefs
KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
KVM: x86: zero apic_arb_prio on reset
drivers/hv: share Hyper-V SynIC constants with userspace
KVM: x86: handle SMBASE as physical address in RSM
KVM: x86: add read_phys to x86_emulate_ops
KVM: x86: removing unused variable
KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
KVM: arm/arm64: Optimize away redundant LR tracking
KVM: s390: use simple switch statement as multiplexer
KVM: s390: drop useless newline in debugging data
KVM: s390: SCA must not cross page boundaries
KVM: arm: Do not indent the arguments of DECLARE_BITMAP
...
This reverts commit 9678cdaae9 ("Use the POWER8 Micro Partition
Prefetch Engine in KVM HV on POWER8") because the original commit had
multiple, partly self-cancelling bugs, that could cause occasional
memory corruption.
In fact the logmpp instruction was incorrectly using register r0 as the
source of the buffer address and operation code, and depending on what
was in r0, it would either do nothing or corrupt the 64k page pointed to
by r0.
The logmpp instruction encoding and the operation code definitions could
be corrected, but then there is the problem that there is no clearly
defined way to know when the hardware has finished writing to the
buffer.
The original commit attempted to work around this by aborting the
write-out before starting the prefetch, but this is ineffective in the
case where the virtual core is now executing on a different physical
core from the one where the write-out was initiated.
These problems plus advice from the hardware designers not to use the
function (since the measured performance improvement from using the
feature was actually mostly negative), mean that reverting the code is
the best option.
Fixes: 9678cdaae9 ("Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8")
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently a CPU running a guest can receive a H_DOORBELL in the
following two cases:
1) When the CPU is napping due to CEDE or there not being a guest
vcpu.
2) The CPU is running the guest vcpu.
Case 1), the doorbell message is not cleared since we were waking up
from nap. Hence when the EE bit gets set on transition from guest to
host, the H_DOORBELL interrupt is delivered to the host and the
corresponding handler is invoked.
However in Case 2), the message gets cleared by the action of taking
the H_DOORBELL interrupt. Since the CPU was running a guest, instead
of invoking the doorbell handler, the code invokes the second-level
interrupt handler to switch the context from the guest to the host. At
this point the setting of the EE bit doesn't result in the CPU getting
the doorbell interrupt since it has already been delivered once. So,
the handler for this doorbell is never invoked!
This causes softlockups if the missed DOORBELL was an IPI sent from a
sibling subcore on the same CPU.
This patch fixes it by explitly invoking the doorbell handler on the
exit path if the exit reason is H_DOORBELL similar to the way an
EXTERNAL interrupt is handled. Since this will also handle Case 1), we
can unconditionally clear the doorbell message in
kvmppc_check_wake_reason.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
QEMU assumes 32 memslots if this extension is not implemented. Although,
current value of KVM_USER_MEM_SLOTS is 32, once KVM_USER_MEM_SLOTS
changes QEMU would take a wrong value.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a bug where the old HPTE value returned by H_REMOVE has
the valid bit clear if the HPTE was an absent HPTE, as happens for
HPTEs for emulated MMIO pages and for RAM pages that have been paged
out by the host. If the absent bit is set, we clear it and set the
valid bit, because from the guest's point of view, the HPTE is valid.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Paolo Bonzini