By default qemu will use MAP_PRIVATE for guest pages. This will write
protect pages and thus break on s390 systems that dont support this feature.
Therefore qemu has a hack to always use MAP_SHARED for s390. But MAP_SHARED
has other problems (no dirty pages tracking, a lot more swap overhead etc.)
Newer systems allow the distinction via KVM_CAP_S390_COW. With this feature
qemu can use the standard qemu alloc if available, otherwise it will use
the old s390 hack.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
We must not run the target cpu after an initial reset. This makes
system_reset more reliable for smp guests.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
A disabled wait usually indicates a guest problem. Dont shutdown the
guest to allow guest dumping.
Have some special cases, e.g. a quiesce disabled wait. In that case
we want to shutdown.
Long term solution might be a crashed/panic indication.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This patch adds reboot support for s390x-softmmu by calling
the generic reboot support in kvm.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Scripted conversion:
sed -i "s/CPUState/CPUS390XState/g" target-s390x/*.[hc]
sed -i "s/#define CPUS390XState/#define CPUState/" target-s390x/cpu.h
Signed-off-by: Andreas Färber <afaerber@suse.de>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
The add_del/running_cpu code and env->halted are tracking stopped cpus.
Sleeping cpus (idle and enabled for interrupts) are waiting inside the
kernel.
No interrupt besides the restart can move a cpu from stopped to
operational. This is already handled over there. So lets just remove
the bogus wakup from the common interrupt delivery, otherwise any
interrupt will wake up a cpu, even if this cpu is stopped (Thus leading
to strange hangs on sigp restart)
This fixes
echo 0 > /sys/devices/system/cpu/cpu0/online
echo 1 > /sys/devices/system/cpu/cpu0/online
in the guest
Signed-off-by: Christian Borntraeger<borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
On s390 a shutdown is the state of all CPUs being either stopped
or disabled (for interrupts) waiting. We have to track the overall
number of running CPUs to call the shutdown sequence accordingly.
This patch implements the counting and shutdown handling for the
kvm path in qemu.
Lets also wrap changes to env->halted and env->exception_index.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
On unknown sigp order codes we print a debug message. This patch
fixes the output, since we want to see the order_code and not
the register numbers.
Patch applies on agraf tree.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
We're now finally emulating an s390x CPU, so we can move quite some logic
from the kvm code out into generic CPU code.
This patch does this and adjusts the interfaces according to what the code
around now expects to be able to call.
Signed-off-by: Alexander Graf <agraf@suse.de>
Currently smp support for kvm does not work. Qemu does a kvm run even on
secondary CPUs which dont have a sane state (initial psw == 0)
triggering some program faults. Architecturally these cpus are in the stopped
state, so we should not do the kvm run ioctl. (these CPUs will be started
by a SIGP restart later during the boot process)
We need to tell the loop that this cpu should not run. Jan Kiszka pointed
out that kvm_arch_process_async_events is the right place to do.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
We need to add some more logic to the CPU description to leverage emulation
of an s390x CPU. This patch adds all the required helpers, fields in CPUState
and constant definitions required for user and system emulation.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
During Jan's rework of the generic KVM layer, he added some more error checks
and actually aborted if something went wrong. Unfortunately, one of the s390
internal error codes slipped through, aborting the VM without needing to.
This patch fixes booting of S390x virtual machines in KVM.
Signed-off-by: Alexander Graf <agraf@suse.de>
CC: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Make the return code of kvm_arch_handle_exit directly usable for
kvm_cpu_exec. This is straightforward for x86 and ppc, just s390
would require more work. Avoid this for now by pushing the return code
translation logic into s390's kvm_arch_handle_exit.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
CC: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
We will broaden the scope of this function on x86 beyond irqchip events.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This ensures env->halt_cond is broadcast, and the loop in
qemu_tcg_wait_io_event and qemu_kvm_wait_io_event is exited
naturally rather than through a timeout.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
We do not check them, and the only arch with non-empty implementations
always returns 0 (this is also true for qemu-kvm).
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
CC: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Provide arch-independent kvm_on_sigbus* stubs to remove the #ifdef'ery
from cpus.c. This patch also fixes --disable-kvm build by providing the
missing kvm_on_sigbus_vcpu kvm-stub.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Instead of splattering the code with #ifdefs and runtime checks for
capabilities we cannot work without anyway, provide central test
infrastructure for verifying their availability both at build and
runtime.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
The s390 target doesn't compile out of the box anymore. This patch fixes all
the obvious glitches that got introduced in the last few weeks.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
For SMP to work with KVM, we need to properly emulate the SIGP Initial Reset
Command. Recent (2.6.32) kernels issue that before the SIGP Reset command that
actually wakes up the vcpu.
This patch makes -smp work on S390x.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Continue vcpu execution in case emulation failure happened while vcpu
was in userspace. In this case #UD will be injected into the guest
allowing guest OS to kill offending process and continue.
Signed-off-by: Gleb Natapov <gleb@redhat.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>
env->exception_index should be cleared with -1, not 0.
See also 821b19fe92.
Spotted by Igor Kovalenko.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
We were being a bit too nice and didn't give the guest an invalid instruction
interrupt.
While that works, it's not exactly the fastest thing to do, since now the
guest doesn't know that we're not really implementing that instruction, so it
continues doing it.
We run into this with the set_page_unstable hint instruction. So let's bail out
in these cases.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
S390x was one of the first platforms that received support for KVM back in the
day. Unfortunately until now there hasn't been a qemu implementation that would
enable users to actually run guests.
So let's include support for KVM S390x in qemu!
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
