Currently, multi threaded TCG with > 1 VCPU gets stuck during IPL, when
the bios tries to switch to the loaded kernel via DIAG 308.
As run_on_cpu() is used, we run into a deadlock after handling the reset.
We need the iolock (just like KVM).
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171116170526.12643-4-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
For now, e.g. host-s390-cpu wasn't exposed to the user. cpu-add, -cpu
and the CPU model qmp interfaces didn't care about the actual type,
as that information was hidden.
This changed with CPU hotplug via device_add. Now the type is visible to
the user. Before we get that supported in a stable version, this is our
last chance to change it.
So change it from "s390-cpu" to "s390x-cpu", to match the architecture
name. Example names are then e.g. z14-s390x-cpu or qemu-s390x-cpu.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171020115803.14093-1-david@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This is a neat way to implement low address protection, whereby
only the first 512 bytes of the first two pages (each 4096 bytes) of
every address space are protected.
Store a tec of 0 for the access exception, this is what is defined by
Enhanced Suppression on Protection in case of a low address protection
(Bit 61 set to 0, rest undefined).
We have to make sure to to pass the access address, not the masked page
address into mmu_translate*().
Drop the check from testblock. So we can properly test this via
kvm-unit-tests.
This will check every access going through one of the MMUs.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171016202358.3633-3-david@redhat.com>
[CH: restored error message for access register mode]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Background: s390x implements Low-Address Protection (LAP). If LAP is
enabled, writing to effective addresses (before any translation)
0-511 and 4096-4607 triggers a protection exception.
So we have subpage protection on the first two pages of every address
space (where the lowcore - the CPU private data resides).
By immediately invalidating the write entry but allowing the caller to
continue, we force every write access onto these first two pages into
the slow path. we will get a tlb fault with the specific accessed
addresses and can then evaluate if protection applies or not.
We have to make sure to ignore the invalid bit if tlb_fill() succeeds.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171016202358.3633-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
When we try to start a CPU with a WAIT PSW, we have to take care that
TCG will actually try to continue executing instructions.
We must therefore really only unhalt the CPU if we don't have a WAIT
PSW. Also document the special order for restart interrupts, which
load a new PSW and change the state to operating.
To keep KVM working, simply don't have a look at the WAIT bit when
loading the PSW. Otherwise the behavior of a restart interrupt when
a CPU stopped would be changed.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-31-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Refactor it to use s390_get_feat_block(). Directly write into the mapped
lowcore with stfl and make sure it is really only compiled if needed.
While at it, add an alignment check for STFLE and avoid
potential_page_fault() by properly restoring the CPU state.
Due to s390_get_feat_block(), we will now also indicate the
"Configuration-z-architectural-mode", which is with new SIGP code the
right thing to do.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-30-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This effectively enables experimental SMP support. Floating interrupts are
still a mess, so allow it but print a big warning. There also seems
to be a problem with CPU hotplug (after the main loop started).
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-27-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[CH: changed insn-data.def as pointed out by Richard]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Implement them like KVM implements/handles them. Both can only be
triggered via SIGP instructions. RESET has (almost) the lowest priority if
the CPU is running, and the highest if the CPU is STOPPED. This is handled
in SIGP code already. On delivery, we only have to care about the
"CPU running" scenario.
STOP is defined to be delivered after all other interrupts have been
delivered. Therefore it has the actual lowest priority.
As both can wake up a CPU if sleeping, indicate them correctly to
external code (e.g. cpu_has_work()).
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-25-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
We want to use the same code base for TCG, so let's cleanly factor it
out.
The sigp mutex is currently not really needed, as everything is
protected by the iothread mutex. But this could change later, so leave
it in place and initialize it properly from common code.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-17-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
KVM handles the wait PSW itself and triggers a WAIT ICPT in case it
really wants to sleep (disabled wait).
This will later allow us to change the order of loading a restart
interrupt and setting a CPU to OPERATING on SIGP RESTART without
changing KVM behavior.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-11-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
If we encounter a WAIT PSW, we have to halt immediately. Using
cpu_loop_exit() at this point feels wrong. Simply leaving
cs->exception_index set doesn't result in an immediate stop.
This is also necessary to properly handle SIGP STOP interrupts later.
The CPU_INTERRUPT_HALT will be processed immediately and properly set
the CPU to halted (also resetting cs->exception_index to EXCP_HLT)
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-10-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Going to OPERATING here looks wrong. A CPU should even never be
!OPERATING at this point. Unhalting will already be done in
cpu_handle_halt() if there is work, so we can drop this statement
completely.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-8-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Currently, enabling/disabling of interrupts is not really supported.
Let's improve interrupt handling code by explicitly checking for
deliverable interrupts only. This is the first step. Checking for
external interrupt subclasses will be done next.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-5-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
There are still some leftovers from old virtio interrupts in there.
Most importantly, we don't have to queue service interrupts anymore.
Just like KVM, we can simply multiplex the SCLP service interrupts and
avoid the queue.
Also, now only valid parameters/cpu_addr will be stored on service
interrupts.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-3-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
External interrupts are currently all handled like floating external
interrupts, they are queued. Let's prepare for a split of floating
and local interrupts by turning INTERRUPT_EXT into a mask.
While we can have various floating external interrupts of one kind, there
is usually only one (or a fixed number) of the local external interrupts.
So turn INTERRUPT_EXT into a mask and properly indicate the kind of
external interrupt. Floating interrupts will have to moved out of
one CPU instance later once we have SMP support.
The only floating external interrupts used right now are SERVICE
interrupts, so let's use that name. Following patches will clean up
SERVICE interrupt injection.
This get's rid of the ugly special handling for cpu timer and clock
comparator interrupts. And we really only store the parameters as
defined by the PoP.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Attributes are not updated via region_add()/region_del(). Attribute changes
lead to a delete first, followed by a new add.
If this would ever not be the case, we would get an error when trying to
register the new slot.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171016144302.24284-6-david@redhat.com>
Tested-by: Joe Clifford <joeclifford@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It might be confusing for some listener implementations that implement
both, region_add and log_start (e.g. KVM) if we call log_start before an
actual region was added using region_add.
This makes current KVM code trigger an assertion
("kvm_section_update_flags: error finding slot"). So let's just reverse
the order instead of tolerating log_start on yet unknown regions.
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171016144302.24284-2-david@redhat.com>
Tested-by: Joe Clifford <joeclifford@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Using virtual memory access is wrong and will soon include low-address
protection checks, which is to be bypassed for STFL.
STFL is a privileged instruction and using LowCore requires
!CONFIG_USER_ONLY, so add the ifdef and move the declaration to the
right place.
This was originally part of a bigger STFL(E) refactoring.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170927170027.8539-4-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
core_id is not needed by linux-user, as the core_id a.k.a. CPU address
is only accessible from kernel space.
Therefore, drop next_core_id and make cpu_index get autoassigned again
for linux-user.
While at it, shield core_id and cpuid completely from linux-user. cpuid
can also only be queried from kernel space.
Suggested-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928134609.16985-5-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Let's move it into the machine, so we trigger the IRQ after setting
ms->possible_cpus (which SCLP uses to construct the list of
online CPUs).
This also fixes a problem reported by Thomas Huth, whereby qemu can be
crashed using the none machine
qemu-s390x-softmmu -M none -monitor stdio
-> device_add qemu-s390-cpu
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928134609.16985-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This makes it easy to access real addresses (prefix) and in addition
checks for valid memory addresses, which is missing when using e.g.
stl_phys().
We can later reuse it to implement low address protection checks (then
we might even decide to introduce yet another MMU for absolute
addresses, just for handling storage keys and low address protection).
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170926183318.12995-3-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
env->psa is a 64bit value, while we copy 4 bytes into the save area,
resulting always in 0 getting stored.
Let's try to reduce such errors by using a proper structure. While at
it, use correct cpu->be conversion (and get_psw_mask()), as we will be
reusing this code for TCG soon.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170922140338.6068-1-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
The STFLE bits for the MSA (extension) facilities simply indicate that
the respective instructions can be executed. The QUERY subfunction can then
be used to identify which features exactly are available.
Availability of subfunctions can also vary on real hardware. For now, we
simply implement a CPU model without any available subfunctions except
QUERY (which is always around).
As all MSA functions behave quite similarly, we can use one translation
handler for now. Prepare the code for implementation of actual subfunctions.
At least MSA is helpful for now, as older Linux kernels require this
facility when compiled for a z9 model. Allow to enable the facilities
for the qemu cpu model.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170920153016.3858-4-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
pflash toggles mr->romd_mode. So this assert does not always hold.
1) a device was added with !mr->romd_mode, therefore effectively not
creating a kvm slot as we want to trap every access (add = false).
2) mr->romd_mode was toggled on before remove it. There is now
actually no slot to remove and the assert is wrong.
So let's just drop the assert.
Reported-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170920145025.19403-1-david@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SCLP correctly indicates the core-id aka. CPU address for each available
CPU.
As the core-id corresponds to cpu_index, also a newly created kvm vcpu
gets assigned this core-id as vcpu id. So SIGP in the kernel works
correctly (it uses the vcpu id to lookup the correct CPU).
So there should be nothing hindering us from hotplugging CPUs in random
core-id order.
This now makes sure that the output from "query-hotpluggable-cpus"
is completely true. Until now, a specific order is implicit. Performance
vice, hotplugging CPUs in non-sequential order might not be the best thing
to do, as VCPU lookup inside KVM might be a little slower. But that
doesn't hinder us from supporting it.
next_core_id is now used by linux user only.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-23-david@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This is the first step to allow hot plugging of CPUs in a non-sequential
order. If a cpu is available ("plugged") can directly be decided by
looking at the cpu state pointer.
This makes sure, that really only cpus attached to the machine are
reported.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-22-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Now that there is only one user of cpu_s390x_create() left, make cpu
creation look like on x86.
- Perform the model/properties split and checks in s390_init_cpus()
- Parse features only once without having to remember if already parsed
- Pass only the typename to s390x_new_cpu()
- Use the typename of an existing CPU for hotplug via cpu-add
Acked-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-21-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
device_del on a CPU will currently do nothing. Let's emit an error
telling that this is will currently not work (there is no architecture
support on s390x). Error message copied from ppc.
(qemu) device_del cpu1
device_del cpu1
CPU hot unplug not supported on this machine
Reviewed-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-18-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
E.g. the following now works:
device_add host-s390-cpu,id=cpu1,core-id=1
The system will perform the same checks as when using cpu_add:
- If the core_id is already in use
- If the next sequential core_id isn't used
- If core-id >= max_cpu is specified
In addition, mixed CPU models are checked. E.g. if starting with
-cpu host and trying to hotplug "qemu-s390-cpu":
"Mixed CPU models are not supported on s390x."
Reviewed-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-17-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Some time ago we discussed that using "id" as property name is not the
right thing to do, as it is a reserved property for other devices and
will not work with device_add.
Switch to the term "core-id" instead, and use it as an equivalent to
"CPU address" mentioned in the PoP. There is no such thing as cpu number,
so rename env.cpu_num to env.core_id. We use "core-id" as this is the
common term to use for device_add later on (x86 and ppc).
We can get rid of cpu->id now. Keep cpu_index and env->core_id in sync.
cpu_index was already implicitly used by e.g. cpu_exists(), so keeping
both in sync seems to be the right thing to do.
cpu_index will now no longer automatically get set via
cpu_exec_realizefn(). For now, we were lucky that both implicitly stayed
in sync.
Our new cpu property "core-id" can be a static property. Range checks can
be avoided by using the correct type and the "setting after realized"
check is done implicitly.
device_add will later need the reserved "id" property. Hotplugging a CPU
on s390x will then be: "device_add host-s390-cpu,id=cpu2,core-id=2".
Reviewed-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-14-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the
guest tries to bring these CPUs up but fails), because we don't support
multiple CPUs on s390x under TCG.
Let's bail out if more than 1 is specified, so we don't raise people's
hope.
Tested-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-12-david@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Flatview will make sure that we can only end up in this function with
memory sections that correspond to exactly one slot. So we don't
have to iterate multiple times. There won't be overlapping slots but
only matching slots.
Properly align the section and look up the corresponding slot. This
heavily simplifies this function.
We can now get rid of kvm_lookup_overlapping_slot().
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170911174933.20789-7-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The way flatview handles memory sections, we will never have overlapping
memory sections in kvm.
address_space_update_topology_pass() will make sure that we will only
get called for
a) an existing memory section for which we only update parameters
(log_start, log_stop).
b) an existing memory section we want to delete (region_del)
c) a brand new memory section we want to add (region_add)
We cannot have overlapping memory sections in kvm as we will first remove
the overlapping sections and then add the ones without conflicts.
Therefore we can remove the complexity for handling prefix and suffix
slots.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170911174933.20789-5-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We already require DESTROY_MEMORY_REGION_WORKS, JOIN_MEMORY_REGIONS_WORKS
was added just half a year later.
In addition, with flatview overlapping memory regions are first
removed before adding the changed one. So we can't really detect joining
memory regions this way.
Let's just get rid of this special handling.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170911174933.20789-2-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's do it just like the other architectures. Introduce kvm-stub.c
for stubs and kvm_s390x.h for the declarations.
Change license to GPL2+ and keep copyright notice.
As we are dropping the sysemu/kvm.h include from cpu.h, fix up includes.
Suggested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170818114353.13455-18-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
cpu.h should only contain what really has to be accessed outside of
target/s390x/. Add internal.h which can only be used inside target/s390x/.
Move everything that isn't fast enough to run away and restructure it
right away. We'll move all kvm_* stuff later.
Minor style fixes to avoid checkpatch warning to:
- struct Lowcore: "{" goes into same line as typedef
- struct LowCore: add spaces around "-" in array length calculations
- time2tod() and tod2time(): move "{" to separate line
- get_per_atmid(): add space between ")" and "?". Move cases by one char.
- get_per_atmid(): drop extra paremthesis around (1 << 6)
Change license of new file to GPL2+ and keep copyright notice.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170818114353.13455-15-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
David Hildenbrand