Commit Graph

1113 Commits

Author SHA1 Message Date
Paolo Bonzini
1c482452d5 KVM: s390: Features and Enhancements for 5.7 part1
1. Allow to disable gisa
 2. protected virtual machines
   Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
   state like guest memory and guest registers anymore. Instead the
   PVMs are mostly managed by a new entity called Ultravisor (UV),
   which provides an API, so KVM and the PV can request management
   actions.
 
   PVMs are encrypted at rest and protected from hypervisor access
   while running.  They switch from a normal operation into protected
   mode, so we can still use the standard boot process to load a
   encrypted blob and then move it into protected mode.
 
   Rebooting is only possible by passing through the unprotected/normal
   mode and switching to protected again.
 
   One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
   add callbacks for inaccessible pages)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJeZf9tAAoJEBF7vIC1phx89J0P/iv3wCoMNDqAttnHa/UQFF04
 njUadNYkAADDrsabIEOs9O+BE1/4BVspnIunE4+xw76p5M/7/g5eIhXWcLudhlnL
 +XtvuEwz/2ffA9JWAAYNKB7cGqBM9BCC+iYzAF9ah6sPLmlDCoF+hRe0g+0tXSON
 cklUJFril9bOcxd/MxrzFLcmipbxT/Z4/10eBY+FHcm6SQGOKAtJH0xL7X3PfPI5
 L/6ZhML9exsj1Iplkrl8BomMRoYOrvfq/jMaZp9SwmfXaOKYmNU3a19MhzfZ593h
 bfR92H8kZRy/TpBd7EnpxYGQ/n53HkUhFMhtqkkkeHW1rCo8ccwC4VfnXb+KqQp+
 nJ8KieWG+OlKKFDuZPl5Gq+jQqjJfzchbyMTYnBNe+GPT5zg76tJXmQyDn5X9p3R
 mfg+9ZEeEonMu7px93Ht1gLdPiC2gjRckjuBDPqMGEhG2z2SQ/MLri+WnproIQRa
 TcE7rZBtuyrGFTq4M4dEcsUW02xnOaav6H57kkl8EwqYwgDHlqoUbt0AvLFyW07a
 RlH7drmhKDwTJkcOhOLeLNM8Un6NvnsLZ8Lbcr9rRf9Z9Lpc+zW88BSwJ7MM/GH8
 FEQM8Omnn8KAJTENpIm3bHHyvsi0kJEhl+c3Ila3QnYzXZbJ3ZDaJZngMAbUUnVl
 YNeFyyALzOgVVBx4kvTm
 =x6Hn
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Features and Enhancements for 5.7 part1

1. Allow to disable gisa
2. protected virtual machines
  Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
  state like guest memory and guest registers anymore. Instead the
  PVMs are mostly managed by a new entity called Ultravisor (UV),
  which provides an API, so KVM and the PV can request management
  actions.

  PVMs are encrypted at rest and protected from hypervisor access
  while running.  They switch from a normal operation into protected
  mode, so we can still use the standard boot process to load a
  encrypted blob and then move it into protected mode.

  Rebooting is only possible by passing through the unprotected/normal
  mode and switching to protected again.

  One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
  add callbacks for inaccessible pages)
2020-03-16 18:19:34 +01:00
Peter Xu
4d39576259 KVM: Remove unnecessary asm/kvm_host.h includes
Remove includes of asm/kvm_host.h from files that already include
linux/kvm_host.h to make it more obvious that there is no ordering issue
between the two headers.  linux/kvm_host.h includes asm/kvm_host.h to
pick up architecture specific settings, and this will never change, i.e.
including asm/kvm_host.h after linux/kvm_host.h may seem problematic,
but in practice is simply redundant.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:34 +01:00
Sean Christopherson
2a49f61dfc KVM: Ensure validity of memslot with respect to kvm_get_dirty_log()
Rework kvm_get_dirty_log() so that it "returns" the associated memslot
on success.  A future patch will rework memslot handling such that
id_to_memslot() can return NULL, returning the memslot makes it more
obvious that the validity of the memslot has been verified, i.e.
precludes the need to add validity checks in the arch code that are
technically unnecessary.

To maintain ordering in s390, move the call to kvm_arch_sync_dirty_log()
from s390's kvm_vm_ioctl_get_dirty_log() to the new kvm_get_dirty_log().
This is a nop for PPC, the only other arch that doesn't select
KVM_GENERIC_DIRTYLOG_READ_PROTECT, as its sync_dirty_log() is empty.

Ideally, moving the sync_dirty_log() call would be done in a separate
patch, but it can't be done in a follow-on patch because that would
temporarily break s390's ordering.  Making the move in a preparatory
patch would be functionally correct, but would create an odd scenario
where the moved sync_dirty_log() would operate on a "different" memslot
due to consuming the result of a different id_to_memslot().  The
memslot couldn't actually be different as slots_lock is held, but the
code is confusing enough as it is, i.e. moving sync_dirty_log() in this
patch is the lesser of all evils.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:25 +01:00
Sean Christopherson
0dff084607 KVM: Provide common implementation for generic dirty log functions
Move the implementations of KVM_GET_DIRTY_LOG and KVM_CLEAR_DIRTY_LOG
for CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT into common KVM code.
The arch specific implemenations are extremely similar, differing
only in whether the dirty log needs to be sync'd from hardware (x86)
and how the TLBs are flushed.  Add new arch hooks to handle sync
and TLB flush; the sync will also be used for non-generic dirty log
support in a future patch (s390).

The ulterior motive for providing a common implementation is to
eliminate the dependency between arch and common code with respect to
the memslot referenced by the dirty log, i.e. to make it obvious in the
code that the validity of the memslot is guaranteed, as a future patch
will rework memslot handling such that id_to_memslot() can return NULL.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:24 +01:00
Sean Christopherson
9d4c197c0e KVM: Drop "const" attribute from old memslot in commit_memory_region()
Drop the "const" attribute from @old in kvm_arch_commit_memory_region()
to allow arch specific code to free arch specific resources in the old
memslot without having to cast away the attribute.  Freeing resources in
kvm_arch_commit_memory_region() paves the way for simplifying
kvm_free_memslot() by eliminating the last usage of its @dont param.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:20 +01:00
Sean Christopherson
414de7abbf KVM: Drop kvm_arch_create_memslot()
Remove kvm_arch_create_memslot() now that all arch implementations are
effectively nops.  Removing kvm_arch_create_memslot() eliminates the
possibility for arch specific code to allocate memory prior to setting
a memslot, which sets the stage for simplifying kvm_free_memslot().

Cc: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:17 +01:00
Michael Mueller
cc674ef252 KVM: s390: introduce module parameter kvm.use_gisa
The boolean module parameter "kvm.use_gisa" controls if newly
created guests will use the GISA facility if provided by the
host system. The default is yes.

  # cat /sys/module/kvm/parameters/use_gisa
  Y

The parameter can be changed on the fly.

  # echo N > /sys/module/kvm/parameters/use_gisa

Already running guests are not affected by this change.

The kvm s390 debug feature shows if a guest is running with GISA.

  # grep gisa /sys/kernel/debug/s390dbf/kvm-$pid/sprintf
  00 01582725059:843303 3 - 08 00000000e119bc01  gisa 0x00000000c9ac2642 initialized
  00 01582725059:903840 3 - 11 000000004391ee22  00[0000000000000000-0000000000000000]: AIV gisa format-1 enabled for cpu 000
  ...
  00 01582725059:916847 3 - 08 0000000094fff572  gisa 0x00000000c9ac2642 cleared

In general, that value should not be changed as the GISA facility
enhances interruption delivery performance.

A reason to switch the GISA facility off might be a performance
comparison run or debugging.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Link: https://lore.kernel.org/r/20200227091031.102993-1-mimu@linux.ibm.com
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:13 +01:00
Christian Borntraeger
13da9ae1cd KVM: s390: protvirt: introduce and enable KVM_CAP_S390_PROTECTED
Now that everything is in place, we can announce the feature.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-02-27 19:47:13 +01:00
Janosch Frank
8a8378fa61 KVM: s390: protvirt: Add UV cpu reset calls
For protected VMs, the VCPU resets are done by the Ultravisor, as KVM
has no access to the VCPU registers.

Note that the ultravisor will only accept a call for the exact reset
that has been requested.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Christian Borntraeger
72f218208f KVM: s390: protvirt: do not inject interrupts after start
As PSW restart is handled by the ultravisor (and we only get a start
notification) we must re-check the PSW after a start before injecting
interrupts.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
3adae0b4ca KVM: s390: protvirt: Mask PSW interrupt bits for interception 104 and 112
We're not allowed to inject interrupts on intercepts that leave the
guest state in an "in-between" state where the next SIE entry will do a
continuation, namely secure instruction interception (104) and secure
prefix interception (112).
As our PSW is just a copy of the real one that will be replaced on the
next exit, we can mask out the interrupt bits in the PSW to make sure
that we do not inject anything.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
7c36a3fcf4 KVM: s390: protvirt: Support cmd 5 operation state
Code 5 for the set cpu state UV call tells the UV to load a PSW from
the SE header (first IPL) or from guest location 0x0 (diag 308 subcode
0/1). Also it sets the cpu into operating state afterwards, so we can
start it.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
fe28c7868f KVM: s390: protvirt: Report CPU state to Ultravisor
VCPU states have to be reported to the ultravisor for SIGP
interpretation, kdump, kexec and reboot.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
e0d2773d48 KVM: s390: protvirt: UV calls in support of diag308 0, 1
diag 308 subcode 0 and 1 require several KVM and Ultravisor interactions.
Specific to these "soft" reboots are

* The "unshare all" UVC
* The "prepare for reset" UVC

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
ea5c68c390 KVM: s390: protvirt: Add program exception injection
Only two program exceptions can be injected for a protected guest:
specification and operand.

For both, a code needs to be specified in the interrupt injection
control of the state description, as the guest prefix page is not
accessible to KVM for such guests.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
811ea79711 KVM: s390: protvirt: Only sync fmt4 registers
A lot of the registers are controlled by the Ultravisor and never
visible to KVM. Also some registers are overlayed, like gbea is with
sidad, which might leak data to userspace.

Hence we sync a minimal set of registers for both SIE formats and then
check and sync format 2 registers if necessary.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
0f30350471 KVM: s390: protvirt: Do only reset registers that are accessible
For protected VMs the hypervisor can not access guest breaking event
address, program parameter, bpbc and todpr. Do not reset those fields
as the control block does not provide access to these fields.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
68cf7b1f13 KVM: s390: protvirt: disallow one_reg
A lot of the registers are controlled by the Ultravisor and never
visible to KVM. Some fields in the sie control block are overlayed, like
gbea. As no known userspace uses the ONE_REG interface on s390 if sync
regs are available, no functionality is lost if it is disabled for
protected guests.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
353cbc6a5b KVM: s390: protvirt: STSI handling
Save response to sidad and disable address checking for protected
guests.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:12 +01:00
Janosch Frank
22d768c3e9 KVM: s390: protvirt: Write sthyi data to instruction data area
STHYI data has to go through the bounce buffer.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Claudio Imbrenda
5322781008 KVM: s390/mm: handle guest unpin events
The current code tries to first pin shared pages, if that fails (e.g.
because the page is not shared) it will export them. For shared pages
this means that we get a new intercept telling us that the guest is
unsharing that page. We will unpin the page at that point in time,
following the same rules as for making a page secure (i.e. waiting for
writeback, no elevated page references, etc.)

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
d274995ec2 KVM: s390: protvirt: handle secure guest prefix pages
The SPX instruction is handled by the ultravisor. We do get a
notification intercept, though. Let us update our internal view.

In addition to that, when the guest prefix page is not secure, an
intercept 112 (0x70) is indicated. Let us make the prefix pages
secure again.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
19e1227768 KVM: S390: protvirt: Introduce instruction data area bounce buffer
Now that we can't access guest memory anymore, we have a dedicated
satellite block that's a bounce buffer for instruction data.

We re-use the memop interface to copy the instruction data to / from
userspace. This lets us re-use a lot of QEMU code which used that
interface to make logical guest memory accesses which are not possible
anymore in protected mode anyway.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
c8aac2344d KVM: s390: protvirt: Add new gprs location handling
Guest registers for protected guests are stored at offset 0x380.  We
will copy those to the usual places.  Long term we could refactor this
or use register access functions.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
e663df91dd KVM: s390: protvirt: Handle spec exception loops
SIE intercept code 8 is used only on exception loops for protected
guests. That means we need to stop the guest when we see it. This is
done by userspace.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Christian Borntraeger
0890ddea1a KVM: s390: protvirt: Add SCLP interrupt handling
The sclp interrupt is kind of special. The ultravisor polices that we
do not inject an sclp interrupt with payload if no sccb is outstanding.
On the other hand we have "asynchronous" event interrupts, e.g. for
console input.
We separate both variants into sclp interrupt and sclp event interrupt.
The sclp interrupt is masked until a previous servc instruction has
finished (sie exit 108).

[frankja@linux.ibm.com: factoring out write_sclp]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Michael Mueller
201ae986ea KVM: s390: protvirt: Implement interrupt injection
This defines the necessary data structures in the SIE control block to
inject machine checks,external and I/O interrupts. We first define the
the interrupt injection control, which defines the next interrupt to
inject. Then we define the fields that contain the payload for machine
checks,external and I/O interrupts.
This is then used to implement interruption injection for the following
list of interruption types:

   - I/O (uses inject io interruption)
     __deliver_io

   - External (uses inject external interruption)
     __deliver_cpu_timer
     __deliver_ckc
     __deliver_emergency_signal
     __deliver_external_call

   - cpu restart (uses inject restart interruption)
     __deliver_restart

   - machine checks (uses mcic, failing address and external damage)
     __write_machine_check

Please note that posted interrupts (GISA) are not used for protected
guests as of today.

The service interrupt is handled in a followup patch.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
da24a0cc58 KVM: s390: protvirt: Instruction emulation
We have two new SIE exit codes dealing with instructions.
104 (0x68) for a secure instruction interception, on which the SIE needs
hypervisor action to complete the instruction. We can piggy-back on the
existing instruction handlers.

108 which is merely a notification and provides data for tracking and
management. For example this is used to tell the host about a new value
for the prefix register. As there will be several special case handlers
in later patches, we handle this in a separate function.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
49710db081 KVM: s390: protvirt: Handle SE notification interceptions
Since there is no interception for load control and load psw
instruction in the protected mode, we need a new way to get notified
whenever we can inject an IRQ right after the guest has just enabled
the possibility for receiving them.

The new interception codes solve that problem by providing a
notification for changes to IRQ enablement relevant bits in CRs 0, 6
and 14, as well a the machine check mask bit in the PSW.

No special handling is needed for these interception codes, the KVM
pre-run code will consult all necessary CRs and PSW bits and inject
IRQs the guest is enabled for.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Christian Borntraeger
1274800792 KVM: s390/mm: Make pages accessible before destroying the guest
Before we destroy the secure configuration, we better make all
pages accessible again. This also happens during reboot, where we reboot
into a non-secure guest that then can go again into secure mode. As
this "new" secure guest will have a new ID we cannot reuse the old page
state.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
fa0c5eabbd KVM: s390: protvirt: Secure memory is not mergeable
KSM will not work on secure pages, because when the kernel reads a
secure page, it will be encrypted and hence no two pages will look the
same.

Let's mark the guest pages as unmergeable when we transition to secure
mode.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
29b40f105e KVM: s390: protvirt: Add initial vm and cpu lifecycle handling
This contains 3 main changes:
1. changes in SIE control block handling for secure guests
2. helper functions for create/destroy/unpack secure guests
3. KVM_S390_PV_COMMAND ioctl to allow userspace dealing with secure
machines

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:11 +01:00
Janosch Frank
3e6c556899 KVM: s390: protvirt: Add UV debug trace
Let's have some debug traces which stay around for longer than the
guest.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:10 +01:00
Ulrich Weigand
f65470661f KVM: s390/interrupt: do not pin adapter interrupt pages
The adapter interrupt page containing the indicator bits is currently
pinned. That means that a guest with many devices can pin a lot of
memory pages in the host. This also complicates the reference tracking
which is needed for memory management handling of protected virtual
machines. It might also have some strange side effects for madvise
MADV_DONTNEED and other things.

We can simply try to get the userspace page set the bits and free the
page. By storing the userspace address in the irq routing entry instead
of the guest address we can actually avoid many lookups and list walks
so that this variant is very likely not slower.

If userspace messes around with the memory slots the worst thing that
can happen is that we write to some other memory within that process.
As we get the the page with FOLL_WRITE this can also not be used to
write to shared read-only pages.

Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch simplification]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:47:10 +01:00
Paolo Bonzini
ef09f4f463 KVM: s390: Fixes and cleanups for 5.6
- fix register corruption
 - ENOTSUPP/EOPNOTSUPP mixed
 - reset cleanups/fixes
 - selftests
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJeNDcAAAoJEBF7vIC1phx8NkcP/2JWMr/9v44LJJ8BfZVFqdP4
 i41pVFIgtI8Ieqjgp+Fuiu/8ELPxfohzBZ1Rm60TPcZlJ+uREmHklG1ZD2iXEJix
 0YqzICadQ4OvJxiFpi/s5+9bzczoxCIEx7CfJ4PTM2V3qtefauFgNtoSMevF9CtK
 6UuPNNjBi6cJuG3uAyqoOZ3vbMNeZ337ffEgBwukR01UxGImXwJ9odPFEwz31hji
 WKEEbnPaXFZUKy2vMSZVcndJKkhb043QFkZBY98D8m5VTSO5UFwpdYuht6QdMSKx
 IrxDN7788e/p4IPOGBWAXuhjYcmAYZh2Ayt7DM53b49XhWifsc6fw4khly2fjr3+
 Wg5Ol13ls2WaeDTGd5c4XQRWpQD27Wnum0yXLaVf2gaTRbTqrrsisWLHL6k/gqyb
 CXqJIr11/sb4zLwlwXPSrOrIz3CRz4DqawF/F0q47rHC7xyGsRzpGU4gP5Aqj8op
 qAMVORoQQjMtH4fVv6/NhIG6srVeonNA5GjI6hkYZ85mEJhy5Nl9lNuyEh4W094D
 fkNSnlWcCG8fyoLih1SHVa7cROVI8G0tfwhk4uSjRCXXtA5B5Rve2LQl3nCP9gUX
 m7Y6Qzm/yusVtaTu+YE8MyXVE2bpvGMR/xeztIR8eYw/LqbodOzxkRLdfeH2cfaD
 VCmFaVuUjTXx5q4xYmIl
 =ZgeW
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fixes and cleanups for 5.6
- fix register corruption
- ENOTSUPP/EOPNOTSUPP mixed
- reset cleanups/fixes
- selftests
2020-02-05 16:15:05 +01:00
Janosch Frank
7de3f1423f KVM: s390: Add new reset vcpu API
The architecture states that we need to reset local IRQs for all CPU
resets. Because the old reset interface did not support the normal CPU
reset we never did that on a normal reset.

Let's implement an interface for the missing normal and clear resets
and reset all local IRQs, registers and control structures as stated
in the architecture.

Userspace might already reset the registers via the vcpu run struct,
but as we need the interface for the interrupt clearing part anyway,
we implement the resets fully and don't rely on userspace to reset the
rest.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-4-frankja@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-01-31 12:50:04 +01:00
Janosch Frank
cca00ebb8a KVM: s390: Cleanup initial cpu reset
The code seems to be quite old and uses lots of unneeded spaces for
alignment, which doesn't really help with readability.

Let's:
* Get rid of the extra spaces
* Remove the ULs as they are not needed on 0s
* Define constants for the CR 0 and 14 initial values
* Use the sizeof of the gcr array to memset it to 0

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-3-frankja@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-01-31 12:49:54 +01:00
Christian Borntraeger
55680890ea KVM: s390: do not clobber registers during guest reset/store status
The initial CPU reset clobbers the userspace fpc and the store status
ioctl clobbers the guest acrs + fpr.  As these calls are only done via
ioctl (and not via vcpu_run), no CPU context is loaded, so we can (and
must) act directly on the sync regs, not on the thread context.

Cc: stable@kernel.org
Fixes: e1788bb995 ("KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load")
Fixes: 31d8b8d41a ("KVM: s390: handle access registers in the run ioctl not in vcpu_put/load")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20200131100205.74720-2-frankja@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-01-31 12:49:24 +01:00
Christian Borntraeger
c611990844 KVM: s390: ENOTSUPP -> EOPNOTSUPP fixups
There is no ENOTSUPP for userspace.

Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Fixes: 5197839354 ("KVM: s390: introduce ais mode modify function")
Fixes: 2c1a48f2e5 ("KVM: S390: add new group for flic")
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-01-31 12:49:21 +01:00
Sean Christopherson
ddd259c9aa KVM: Drop kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit()
Remove kvm_arch_vcpu_init() and kvm_arch_vcpu_uninit() now that all
arch specific implementations are nops.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27 19:59:33 +01:00
Sean Christopherson
afede96df5 KVM: Drop kvm_arch_vcpu_setup()
Remove kvm_arch_vcpu_setup() now that all arch specific implementations
are nops.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27 19:59:28 +01:00
Sean Christopherson
ff72bb55cb KVM: s390: Manually invoke vcpu setup during kvm_arch_vcpu_create()
Rename kvm_arch_vcpu_setup() to kvm_s390_vcpu_setup() and manually call
the new function during kvm_arch_vcpu_create().  Define an empty
kvm_arch_vcpu_setup() as it's still required for compilation.  This
is effectively a nop as kvm_arch_vcpu_create() and kvm_arch_vcpu_setup()
are called back-to-back by common KVM code.  Obsoleting
kvm_arch_vcpu_setup() paves the way for its removal.

Note, gmap_remove() is now called if setup fails, as s390 was previously
freeing it via kvm_arch_vcpu_destroy(), which is called by common KVM
code if kvm_arch_vcpu_setup() fails.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27 19:59:27 +01:00
Sean Christopherson
e529ef66e6 KVM: Move vcpu alloc and init invocation to common code
Now that all architectures tightly couple vcpu allocation/free with the
mandatory calls to kvm_{un}init_vcpu(), move the sequences verbatim to
common KVM code.

Move both allocation and initialization in a single patch to eliminate
thrash in arch specific code.  The bisection benefits of moving the two
pieces in separate patches is marginal at best, whereas the odds of
introducing a transient arch specific bug are non-zero.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-27 19:59:20 +01:00
Sean Christopherson
4543bdc088 KVM: Introduce kvm_vcpu_destroy()
Add kvm_vcpu_destroy() and wire up all architectures to call the common
function instead of their arch specific implementation.  The common
destruction function will be used by future patches to move allocation
and initialization of vCPUs to common KVM code, i.e. to free resources
that are allocated by arch agnostic code.

No functional change intended.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 09:19:11 +01:00
Sean Christopherson
a2017f17fa KVM: s390: Invoke kvm_vcpu_init() before allocating sie_page
Now that s390's implementation of kvm_arch_vcpu_init() is empty, move
the call to kvm_vcpu_init() above the allocation of the sie_page.  This
paves the way for moving vcpu allocation and initialization into common
KVM code without any associated functional change.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 09:19:08 +01:00
Sean Christopherson
321f8ee559 KVM: s390: Move guts of kvm_arch_vcpu_init() into kvm_arch_vcpu_create()
Move all of kvm_arch_vcpu_init(), which is invoked at the very end of
kvm_vcpu_init(), into kvm_arch_vcpu_create() in preparation of moving
the call to kvm_vcpu_init().  Moving kvm_vcpu_init() is itself a
preparatory step for moving allocation and initialization to common KVM
code.

No functional change inteded.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 09:19:08 +01:00
Sean Christopherson
897cc38eaa KVM: Add kvm_arch_vcpu_precreate() to handle pre-allocation issues
Add a pre-allocation arch hook to handle checks that are currently done
by arch specific code prior to allocating the vCPU object.  This paves
the way for moving the allocation to common KVM code.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 09:19:07 +01:00
Paolo Bonzini
fe289ebb65 KVM: s390: small fixes and enhancements
- selftest improvements
 - yield improvements
 - cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJd0k9KAAoJEBF7vIC1phx8jecP/15y4vJABaNMCb/zzNYEncxr
 lJf8ZeW+257eiEhsmmju4eM8l9/3RzsJM9WXSj91MBRu+xlkt+cyla/TC+CEKMxW
 Z8yd3AkaIPTMDBY/n6QSqDusrUwfR01iM02mr/IKguG/HeCKgLksN03ZU00mc09q
 Ogo+Cl3AdNnIds+5vkIOQAc+CHM3SGjEfyZCqoTwjn46jsKNQeDrq3hHX9RMG4FF
 BxVcSx5rCFCYyb9eruCCK4OHrEEwdJ4l0udkblRjIl+T9Y8LgoXO1/KGIggVL5UJ
 +Smoc/soXMdkOAhefn/2fB1dBRNBaUpvB5xtAd4BHyRjPomw93sftScW06qfiZuo
 0nBiDgTyilpi8dpojyu2vUpYj7NQXTI4ZoHOMTsXOhk6cqGqm4loLb4xdJ8FCoc9
 04Yf1GCfbyEovoyLq1BkL1qD5ZUBecUfYWQGS1xf0+U6/hvn5lQOGeINNe/ho2Zl
 jU1lsFuGGyKs3G5qpk0Dz8UgbRqOYC58VlGQ1eOcNVksTf7qG+MZ3c6kall7CfXg
 MFcK/PuSxyTfrr5CApyK3Gpqu32aMV0rComd6Bv28DlsTRA9F1TJ5WQTO3HUhV9R
 iiqbMAx0s1xHZp6K/VsCvYRjdVyKU7/sQ6OxRmRTybjjKajKijQjMlE2f1Nr0liD
 PKsQjv2kTvrtMDzOhWFu
 =zHPF
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: small fixes and enhancements

- selftest improvements
- yield improvements
- cleanups
2019-11-18 13:16:46 +01:00
Christian Borntraeger
c7b7de6312 KVM: s390: Do not yield when target is already running
If the target is already running we do not need to yield.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-10-10 13:18:40 +02:00
Christian Borntraeger
8474e5cac0 KVM: s390: count invalid yields
To analyze some performance issues with lock contention and scheduling
it is nice to know when diag9c did not result in any action or when
no action was tried.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-10-10 13:18:38 +02:00