ENOTSUPP is not supposed to leak to userspace so lets just use
EOPNOTSUPP everywhere.
Doesn't fix a bug, but makes future reviews easier.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This patch corrects the checking of the new address for the prefix register.
On s390, the prefix register is used to address the cpu's lowcore (address
0...8k). This check is supposed to verify that the memory is readable and
present.
copy_from_guest is a helper function, that can be used to read from guest
memory. It applies prefixing, adds the start address of the guest memory in
user, and then calls copy_from_user. Previous code was obviously broken for
two reasons:
- prefixing should not be applied here. The current prefix register is
  going to be updated soon, and the address we're looking for will be
  0..8k after we've updated the register
- we're adding the guest origin (gmsor) twice: once in subject code
  and once in copy_from_guest

With kuli, we did not hit this problem because (a) we were lucky with
previous prefix register content, and (b) our guest memory was mmaped
very low into user address space.

Cc: stable@kernel.org
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Reported-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This patch relocates the variables kvm-s390 uses to track guest mem addr/size.
As discussed dropping the variables at struct kvm_arch level allows to use the
common vcpu->request based mechanism to reload guest memory if e.g. changes
via set_memory_region.

The kick mechanism introduced in this series is used to ensure running vcpus
leave guest state to catch the update.
Signed-off-by: NChristian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

To ensure vcpu's come out of guest context in certain cases this patch adds a
s390 specific way to kick them out of guest context. Currently it kicks them
out to rerun the vcpu_run path in the s390 code, but the mechanism itself is
expandable and with a new flag we could also add e.g. kicks to userspace etc.
Signed-off-by: NChristian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Check whether index is within bounds before testing the element.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The floating interrupt lock is only taken in process context. We can
replace all spin_lock_bh with standard spin_lock calls.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NChristian Ehrhardt <ehrhardt@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

KVM on s390 does not support the ESA/390 architecture. We refuse to
change the architecture mode and print a warning. This patch removes
the printk for several reasons:

o A malicious guest can flood host dmesg
o The old message had no newline
o there is no connection between the message and the failing guest

This patch simply removes the printk. We already set the condition
code to 3 - the guest knows that something went wrong.
Reported-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We can get an exit for instructions starting with 0xae, even if the guest is
in userspace. Lets make sure, that the signal processor handler is only called
in guest supervisor mode. Otherwise, send a program check.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

All registers are unsigned long types. This patch changes all occurences
of guestaddr in gaccess from u64 to unsigned long.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

While doing some tests with our lcrash implementation I have seen a
naming conflict with prefix_info in kvm_host.h vs. addrconf.h

To avoid future conflicts lets rename private definitions in
asm/kvm_host.h by adding the kvm_s390 prefix.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch introduces in-kernel handling of _some_ sigp interprocessor
signals (similar to ipi).
kvm_s390_handle_sigp() decodes the sigp instruction and calls individual
handlers depending on the operation requested:
- sigp sense tries to retrieve information such as existence or running state
  of the remote cpu
- sigp emergency sends an external interrupt to the remove cpu
- sigp stop stops a remove cpu
- sigp stop store status stops a remote cpu, and stores its entire internal
  state to the cpus lowcore
- sigp set arch sets the architecture mode of the remote cpu. setting to
  ESAME (s390x 64bit) is accepted, setting to ESA/S390 (s390, 31 or 24 bit) is
  denied, all others are passed to userland
- sigp set prefix sets the prefix register of a remote cpu

For implementation of this, the stop intercept indication starts to get reused
on purpose: a set of action bits defines what to do once a cpu gets stopped:
ACTION_STOP_ON_STOP  really stops the cpu when a stop intercept is recognized
ACTION_STORE_ON_STOP stores the cpu status to lowcore when a stop intercept is
                     recognized
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>