Do not write nmi_pending, sipi_vector, and mpstate unless we at least go
through a reset. And TSC as well as KVM wallclocks should only be
written on full sync, otherwise we risk to drop some time on state
read-modify-write.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This grand cleanup drops all reset and vmsave/load related
synchronization points in favor of four(!) generic hooks:
- cpu_synchronize_all_states in qemu_savevm_state_complete
(initial sync from kernel before vmsave)
- cpu_synchronize_all_post_init in qemu_loadvm_state
(writeback after vmload)
- cpu_synchronize_all_post_init in main after machine init
- cpu_synchronize_all_post_reset in qemu_system_reset
(writeback after system reset)
These writeback points + the existing one of VCPU exec after
cpu_synchronize_state map on three levels of writeback:
- KVM_PUT_RUNTIME_STATE (during runtime, other VCPUs continue to run)
- KVM_PUT_RESET_STATE (on synchronous system reset, all VCPUs stopped)
- KVM_PUT_FULL_STATE (on init or vmload, all VCPUs stopped as well)
This level is passed to the arch-specific VCPU state writing function
that will decide which concrete substates need to be written. That way,
no writer of load, save or reset functions that interact with in-kernel
KVM states will ever have to worry about synchronization again. That
also means that a lot of reasons for races, segfaults and deadlocks are
eliminated.
cpu_synchronize_state remains untouched, just as Anthony suggested. We
continue to need it before reading or writing of VCPU states that are
also tracked by in-kernel KVM subsystems.
Consequently, this patch removes many cpu_synchronize_state calls that
are now redundant, just like remaining explicit register syncs.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
So far we synchronized any dirty VCPU state back into the kernel before
updating the guest debug state. This was a tribute to a deficite in x86
kernels before 2.6.33. But as this is an arch-dependent issue, it is
better handle in the x86 part of KVM and remove the writeback point for
generic code. This also avoids overwriting the flushed state later on if
user space decides to change some more registers before resuming the
guest.
We furthermore need to reinject guest exceptions via the appropriate
mechanism. That is KVM_SET_GUEST_DEBUG for older kernels and
KVM_SET_VCPU_EVENTS for recent ones. Using both mechanisms at the same
time will cause state corruptions.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Remove all references to KVM_CR3_CACHE as it was never implemented.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Hi,
Kevin and I have agreed on the approach for this one now. So here is
the latest version of the patch for QEMU, submitting e820 reservation
entries via fw_cfg.
Cheers,
Jes
Use qemu-cfg to provide the BIOS with an optional table of e820 entries.
Notify the BIOS of the location of the TSS+EPT range to by reserving
it via the e820 table.
This matches a corresponding patch for Seabios, however older versions
of Seabios will default to the hardcoded address range and stay
compatible with current QEMU.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
From qemu-kvm: Kernels before 2.6.30 misreported some essential CPU
features via KVM_GET_SUPPORTED_CPUID. Fix them up.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
The final version of VCPU events in 2.6.33 will allow to skip
nmi_pending and sipi_vector on KVM_SET_VCPU_EVENTS. For now let's write
them unconditionally, which is unproblematic for upstream due to missing
SMP support. Future version which enable SMP will write them only on
reset.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Initialize KVM paravirt cpuid leaf and allow user to control guest
visible PV features through -cpu flag.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Without this qemu can even start on kvm modules with events support
since default value of exception_injected in zero and this is #DE
exception.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Marcelo correctly remarked that there are usage conflicts between QEMU
core code and KVM /wrt exception_index. So spend a separate field and
also save/restore it properly.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Currently, the msrs involved in setting up pvclock are not saved over
migration and/or save/restore. This patch puts their value in special
fields in our CPUState, and deal with them using vmstate.
kvm also has to account for it, by including them in the msr list
for the ioctls.
This is a backport from qemu-kvm.git
[v2: sucessfully build without kerneldir ]
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
KVM_GET_MSR_INDEX_LIST returns -E2BIG when the provided space is too
small for all MSRs. But this is precisely the error we trigger with the
initial request in order to obtain that size. Do not fail in that case.
This caused a subtle corruption of the guest state as MSR_STAR was not
properly saved/restored. The corruption became visible with latest kvm
optimizing the MSR updates.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch extends the qemu-kvm state sync logic with support for
KVM_GET/SET_VCPU_EVENTS, giving access to yet missing exception,
interrupt and NMI states.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Drop interrupt_bitmap from the cpustate and solely rely on the integer
interupt_injected. This prepares us for the new injected-interrupt
interface, which will deprecate the bitmap, while preserving
compatibility.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Allocate enough memory for KVM_GET_MSR_INDEX_LIST as older kernels shot
far beyond their limits, corrupting user space memory.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The KVM kernel will disable all bits in CPUID which are not present in
the host. As this is mostly true for the hypervisor bit (1.ecx),
preserve its value before the trim and restore it afterwards.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If we want to trim the user provided CPUID bits for KVM to be not greater
than that of the host, we should not remove the bits _after_ we sent
them to the kernel.
This fixes the masking of features that are not present on the host by
moving the trim function and it's call from helper.c to kvm.c.
It helps to use -cpu host.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Save and restore all so far neglected KVM-specific CPU states. Handling
the TSC stabilizes migration in KVM mode. The interrupt_bitmap and
mp_state are currently unused, but will become relevant for in-kernel
irqchip support. By including proper saving/restoring already, we avoid
having to increment CPU_SAVE_VERSION later on once again.
v2:
- initialize mp_state runnable (for the boot CPU)
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
KVM_GET_SUPPORTED_CPUID has been known to fail to return -E2BIG
when it runs out of entries. Detect this by always trying again
with a bigger table if the ioctl() fills the table.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
kvm does not support all cpu features; add support for dunamically querying
the supported feature set.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Fix (more or less) spurious guest boot failures due to corrupted cpuid
states. The reason was insufficient initialization of cpuid entries
before passing them to the kernel.
At this chance also fix improper entry pointer progression and simplify
the code a bit.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7167 c046a42c-6fe2-441c-8c8c-71466251a162
As cpu_memory_rw_debug is now capable of modifying ROM, we can drop our
own patch function.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6906 c046a42c-6fe2-441c-8c8c-71466251a162
This is a backport of the guest debugging support for the KVM
accelerator that is now part of the KVM tree. It implements the reworked
KVM kernel API for guest debugging (KVM_CAP_SET_GUEST_DEBUG) which is
not yet part of any mainline kernel but will probably be 2.6.30 stuff.
So far supported is x86, but PPC is expected to catch up soon.
Core features are:
- unlimited soft-breakpoints via code patching
- hardware-assisted x86 breakpoints and watchpoints
Changes in this version:
- use generic hook cpu_synchronize_state to transfer registers between
user space and kvm
- push kvm_sw_breakpoints into KVMState
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6825 c046a42c-6fe2-441c-8c8c-71466251a162
Incrementing the array index was missed in the previous series which causes
us to not store all the values.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6617 c046a42c-6fe2-441c-8c8c-71466251a162
cpuid function 2 can have multiple values to describe cache behaviour.
Loop till we have fetched all the values.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6567 c046a42c-6fe2-441c-8c8c-71466251a162
CPUID functions 4, 0xb and 0xd have sub-leaf values which depend on the
input value of ECX. Store these values as well.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6566 c046a42c-6fe2-441c-8c8c-71466251a162
The CPUID instruction takes the value of ECX as an input parameter
in addition to the value of EAX as the count for functions 4, 0xb
and 0xd. Make sure we pass the value to the instruction.
Also convert to the qemu-style whitespace for the surrounding code.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6565 c046a42c-6fe2-441c-8c8c-71466251a162
It seems that the conversion of the kernel-delivered eflags state into
qemu's internal split representation was once needed in an older kvm
design (register read-back may have taken place from inside cpu_exec).
Today it is plain wrong and causes incorrect cpu state reporting (gdb,
monitor) and should also corrupt its saving (savevm, migration). Drop
the related lines.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6461 c046a42c-6fe2-441c-8c8c-71466251a162
Hollis Blanchard noticed that the last commit was not sufficient. We also need
to initialize the msr size in our newly allocated list.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6018 c046a42c-6fe2-441c-8c8c-71466251a162
I believe this was spotted by Gerd Hoffman but I can't find his patch
now. This will cause very subtle corruption on the heap because we
don't allocate the appropriately sized buffer.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6017 c046a42c-6fe2-441c-8c8c-71466251a162
Fix crash with kvm enabled.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5984 c046a42c-6fe2-441c-8c8c-71466251a162
The third argument to ioctl is a ... which allows any value to be passed. In
practice, glibc always treats the argument as a void *.
Do the same thing for the kvm ioctls to keep things consistent with a
traditional ioctl.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5715 c046a42c-6fe2-441c-8c8c-71466251a162
