Instead of adding a plethora of new KVM_CAP_XEN_FOO capabilities, just
add bits to the return value of KVM_CAP_XEN_HVM.
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>

Add a new exit reason for emulator to handle Xen hypercalls.

Since this means KVM owns the ABI, dispense with the facility for the
VMM to provide its own copy of the hypercall pages; just fill them in
directly using VMCALL/VMMCALL as we do for the Hyper-V hypercall page.

This behaviour is enabled by a new INTERCEPT_HCALL flag in the
KVM_XEN_HVM_CONFIG ioctl structure, and advertised by the same flag
being returned from the KVM_CAP_XEN_HVM check.

Rename xen_hvm_config() to kvm_xen_write_hypercall_page() and move it
to the nascent xen.c while we're at it, and add a test case.
Signed-off-by: NJoao Martins <joao.m.martins@oracle.com>
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>

Commit 181f4948 ("KVM: x86: fix CPUID entries returned by
KVM_GET_CPUID2 ioctl") revealed that we're not testing KVM_GET_CPUID2
ioctl at all. Add a test for it and also check that from inside the guest
visible CPUIDs are equal to it's output.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210129161821.74635-1-vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This test will check the effect of various CPUID settings on the
MSR_IA32_PERF_CAPABILITIES MSR, check that whatever user space writes
with KVM_SET_MSR is _not_ modified from the guest and can be retrieved
with KVM_GET_MSR, and check that invalid LBR formats are rejected.
Signed-off-by: NLike Xu <like.xu@linux.intel.com>
Message-Id: <20210201051039.255478-12-like.xu@linux.intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a memslot modification stress test in which a memslot is repeatedly
created and removed while vCPUs access memory in another memslot. Most
userspaces do not create or remove memslots on running VMs which makes
it hard to test races in adding and removing memslots without a
dedicated test. Adding and removing a memslot also has the effect of
tearing down the entire paging structure, which leads to more page
faults and pressure on the page fault handling path than a one-and-done
memory population test.
Reviewed-by: NJacob Xu <jacobhxu@google.com>
Signed-off-by: NBen Gardon <bgardon@google.com>
Message-Id: <20210112214253.463999-7-bgardon@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When a guest is using xAPIC KVM allocates a backing page for the required
EPT entry for the APIC access address set in the VMCS. If mm decides to
move that page the KVM mmu notifier will update the VMCS with the new
HPA. This test induces a page move to test that APIC access continues to
work correctly. It is a directed test for
commit e649b3f0 "KVM: x86: Fix APIC page invalidation race".

Tested: ran for 1 hour on a skylake, migrating backing page every 1ms

Depends on patch "selftests: kvm: Add exception handling to selftests"
from aaronlewis@google.com that has not yet been queued.
Signed-off-by: NPeter Shier <pshier@google.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NRicardo Koller <ricarkol@google.com>
Message-Id: <20201105223823.850068-1-pshier@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

It's not conventional C to put non-inline functions in header
files. Create a source file for the functions instead. Also
reduce the amount of globals and rename the functions to
something less generic.
Reviewed-by: NBen Gardon <bgardon@google.com>
Reviewed-by: NPeter Xu <peterx@redhat.com>
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-Id: <20201218141734.54359-4-drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

demand_paging_test, dirty_log_test, and dirty_log_perf_test have
redundant guest mode code. Factor it out.

Also, while adding a new include, remove the ones we don't need.
Reviewed-by: NBen Gardon <bgardon@google.com>
Reviewed-by: NPeter Xu <peterx@redhat.com>
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-Id: <20201218141734.54359-2-drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Both user_msr_test and userspace_msr_exit_test tests the functionality
of kvm_msr_filter.  Instead of testing this feature in two tests, merge
them together, so there is only one test for this feature.
Signed-off-by: NAaron Lewis <aaronlewis@google.com>
Message-Id: <20201204172530.2958493-1-aaronlewis@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a selftest to test that when the ioctl KVM_X86_SET_MSR_FILTER is
called with an MSR list, those MSRs exit to userspace.

This test uses 3 MSRs to test this:
  1. MSR_IA32_XSS, an MSR the kernel knows about.
  2. MSR_IA32_FLUSH_CMD, an MSR the kernel does not know about.
  3. MSR_NON_EXISTENT, an MSR invented in this test for the purposes of
     passing a fake MSR from the guest to userspace.  KVM just acts as a
     pass through.

Userspace is also able to inject a #GP.  This is demonstrated when
MSR_IA32_XSS and MSR_IA32_FLUSH_CMD are misused in the test.  When this
happens a #GP is initiated in userspace to be thrown in the guest which is
handled gracefully by the exception handling framework introduced earlier
in this series.

Tests for the generic instruction emulator were also added.  For this to
work the module parameter kvm.force_emulation_prefix=1 has to be enabled.
If it isn't enabled the tests will be skipped.

A test was also added to ensure the MSR permission bitmap is being set
correctly by executing reads and writes of MSR_FS_BASE and MSR_GS_BASE
in the guest while alternating which MSR userspace should intercept.  If
the permission bitmap is being set correctly only one of the MSRs should
be coming through at a time, and the guest should be able to read and
write the other one directly.
Signed-off-by: NAaron Lewis <aaronlewis@google.com>
Reviewed-by: NAlexander Graf <graf@amazon.com>
Message-Id: <20201012194716.3950330-5-aaronlewis@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The DIAGNOSE 0x0318 instruction, unique to s390x, is a privileged call
that must be intercepted via SIE, handled in userspace, and the
information set by the instruction is communicated back to KVM.

To test the instruction interception, an ad-hoc handler is defined which
simply has a VM execute the instruction and then userspace will extract
the necessary info. The handler is defined such that the instruction
invocation occurs only once. It is up to the caller to determine how the
info returned by this handler should be used.

The diag318 info is communicated from userspace to KVM via a sync_regs
call. This is tested during a sync_regs test, where the diag318 info is
requested via the handler, then the info is stored in the appropriate
register in KVM via a sync registers call.

If KVM does not support diag318, then the tests will print a message
stating that diag318 was skipped, and the asserts will simply test
against a value of 0.
Signed-off-by: NCollin Walling <walling@linux.ibm.com>
Link: https://lore.kernel.org/r/20201207154125.10322-1-walling@linux.ibm.comAcked-by: NJanosch Frank <frankja@linux.ibm.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-Id: <20201111122636.73346-10-drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The dirty log perf test will time verious dirty logging operations
(enabling dirty logging, dirtying memory, getting the dirty log,
clearing the dirty log, and disabling dirty logging) in order to
quantify dirty logging performance. This test can be used to inform
future performance improvements to KVM's dirty logging infrastructure.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.
Signed-off-by: NBen Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-6-bgardon@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Remove the clear_dirty_log test, instead merge it into the existing
dirty_log_test.  It should be cleaner to use this single binary to do
both tests, also it's a preparation for the upcoming dirty ring test.

The default behavior will run all the modes in sequence.
Reviewed-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20201001012233.6013-1-peterx@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add support for the SVE registers to get-reg-list and create a
new test, get-reg-list-sve, which tests them when running on a
machine with SVE support.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-Id: <20201029201703.102716-5-drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Check for KVM_GET_REG_LIST regressions. The blessed list was
created by running on v4.15 with the --core-reg-fixup option.
The following script was also used in order to annotate system
registers with their names when possible. When new system
registers are added the names can just be added manually using
the same grep.

while read reg; do
	if [[ ! $reg =~ ARM64_SYS_REG ]]; then
		printf "\t$reg\n"
		continue
	fi
	encoding=$(echo "$reg" | sed "s/ARM64_SYS_REG(//;s/),//")
	if ! name=$(grep "$encoding" ../../../../arch/arm64/include/asm/sysreg.h); then
		printf "\t$reg\n"
		continue
	fi
	name=$(echo "$name" | sed "s/.*SYS_//;s/[\t ]*sys_reg($encoding)$//")
	printf "\t$reg\t/* $name */\n"
done < <(aarch64/get-reg-list --core-reg-fixup --list)
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-Id: <20201029201703.102716-3-drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a set of tests that ensure the guest cannot access paravirtual msrs
and hypercalls that have been disabled in the KVM_CPUID_FEATURES leaf.
Expect a #GP in the case of msr accesses and -KVM_ENOSYS from
hypercalls.

Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: NOliver Upton <oupton@google.com>
Reviewed-by: NPeter Shier <pshier@google.com>
Reviewed-by: NAaron Lewis <aaronlewis@google.com>
Message-Id: <20201027231044.655110-7-oupton@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add the infrastructure needed to enable exception handling in selftests.
This allows any of the exception and interrupt vectors to be overridden
in the guest.
Signed-off-by: NAaron Lewis <aaronlewis@google.com>
Reviewed-by: NAlexander Graf <graf@amazon.com>
Message-Id: <20201012194716.3950330-4-aaronlewis@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a regression test for commit 671ddc70 ("KVM: nVMX: Don't leak
L1 MMIO regions to L2").

First, check to see that an L2 guest can be launched with a valid
APIC-access address that is backed by a page of L1 physical memory.

Next, set the APIC-access address to a (valid) L1 physical address
that is not backed by memory. KVM can't handle this situation, so
resuming L2 should result in a KVM exit for internal error
(emulation).
Signed-off-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NRicardo Koller <ricarkol@google.com>
Reviewed-by: NPeter Shier <pshier@google.com>
Message-Id: <20201026180922.3120555-1-jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

KVM special-cases writes to MSR_IA32_TSC so that all CPUs have
the same base for the TSC.  This logic is complicated, and we
do not want it to have any effect once the VM is started.

In particular, if any guest started to synchronize its TSCs
with writes to MSR_IA32_TSC rather than MSR_IA32_TSC_ADJUST,
the additional effect of kvm_write_tsc code would be uncharted
territory.

Therefore, this patch makes writes to MSR_IA32_TSC behave
essentially the same as writes to MSR_IA32_TSC_ADJUST when
they come from the guest.  A new selftest (which passes
both before and after the patch) checks the current semantics
of writes to MSR_IA32_TSC and MSR_IA32_TSC_ADJUST originating
from both the host and the guest.

Upcoming work to remove the special side effects
of host-initiated writes to MSR_IA32_TSC and MSR_IA32_TSC_ADJUST
will be able to build onto this test, adjusting the host side
to use the new APIs and achieve the same effect.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Now that we have the ability to handle MSRs from user space and also to
select which ones we do want to prevent in-kernel KVM code from handling,
let's add a selftest to show case and verify the API.
Signed-off-by: NAlexander Graf <graf@amazon.com>

Message-Id: <20200925143422.21718-9-graf@amazon.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Marcelo reports that kvm selftests fail to build with
"make ARCH=x86_64":

gcc -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99
 -fno-stack-protector -fno-PIE -I../../../../tools/include
 -I../../../../tools/arch/x86_64/include  -I../../../../usr/include/
 -Iinclude -Ilib -Iinclude/x86_64 -I.. -c lib/kvm_util.c
 -o /var/tmp/20200604202744-bin/lib/kvm_util.o

In file included from lib/kvm_util.c:11:
include/x86_64/processor.h:14:10: fatal error: asm/msr-index.h: No such
 file or directory

 #include <asm/msr-index.h>
          ^~~~~~~~~~~~~~~~~
compilation terminated.

"make ARCH=x86", however, works. The problem is that arch specific headers
for x86_64 live in 'tools/arch/x86/include', not in
'tools/arch/x86_64/include'.

Fixes: 66d69e08 ("selftests: fix kvm relocatable native/cross builds and installs")
Reported-by: NMarcelo Bandeira Condotta <mcondotta@redhat.com>
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200605142028.550068-1-vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When a nested VM with a VMX-preemption timer is migrated, verify that the
nested VM and its parent VM observe the VMX-preemption timer exit close to
the original expiration deadline.
Signed-off-by: NMakarand Sonare <makarandsonare@google.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <20200526215107.205814-3-makarandsonare@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Covers fundamental tests for KVM_SET_GUEST_DEBUG. It is very close to the debug
test in kvm-unit-test, but doing it from outside the guest.
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20200505205000.188252-4-peterx@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

kvm test Makefile doesn't fully support cross-builds and installs.
UNAME_M = $(shell uname -m) variable is used to define the target
programs and libraries to be built from arch specific sources in
sub-directories.

For cross-builds to work, UNAME_M has to map to ARCH and arch specific
directories and targets in this Makefile.

UNAME_M variable to used to run the compiles pointing to the right arch
directories and build the right targets for these supported architectures.

TEST_GEN_PROGS and LIBKVM are set using UNAME_M variable.
LINUX_TOOL_ARCH_INCLUDE is set using ARCH variable.

x86_64 targets are named to include x86_64 as a suffix and directories
for includes are in x86_64 sub-directory. s390x and aarch64 follow the
same convention. "uname -m" doesn't result in the correct mapping for
s390x and aarch64. Fix it to set UNAME_M correctly for s390x and aarch64
cross-builds.

In addition, Makefile doesn't create arch sub-directories in the case of
relocatable builds and test programs under s390x and x86_64 directories
fail to build. This is a problem for native and cross-builds. Fix it to
create all necessary directories keying off of TEST_GEN_PROGS.

The following use-cases work with this change:

Native x86_64:
make O=/tmp/kselftest -C tools/testing/selftests TARGETS=kvm install \
 INSTALL_PATH=$HOME/x86_64

arm64 cross-build:
make O=$HOME/arm64_build/ ARCH=arm64 HOSTCC=gcc \
	CROSS_COMPILE=aarch64-linux-gnu- defconfig

make O=$HOME/arm64_build/ ARCH=arm64 HOSTCC=gcc \
	CROSS_COMPILE=aarch64-linux-gnu- all

make kselftest-install TARGETS=kvm O=$HOME/arm64_build ARCH=arm64 \
	HOSTCC=gcc CROSS_COMPILE=aarch64-linux-gnu-

s390x cross-build:
make O=$HOME/s390x_build/ ARCH=s390 HOSTCC=gcc \
	CROSS_COMPILE=s390x-linux-gnu- defconfig

make O=$HOME/s390x_build/ ARCH=s390 HOSTCC=gcc \
	CROSS_COMPILE=s390x-linux-gnu- all

make kselftest-install TARGETS=kvm O=$HOME/s390x_build/ ARCH=s390 \
	HOSTCC=gcc CROSS_COMPILE=s390x-linux-gnu- all

No regressions in the following use-cases:
make -C tools/testing/selftests TARGETS=kvm
make kselftest-all TARGETS=kvm
Signed-off-by: NShuah Khan <skhan@linuxfoundation.org>

Make set_memory_region_test available on all architectures by wrapping
the bits that are x86-specific in ifdefs.  A future testcase
to create the maximum number of memslots will be architecture
agnostic.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200410231707.7128-10-sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The steal-time test confirms what is reported to the guest as stolen
time is consistent with the run_delay reported for the VCPU thread
on the host. Both x86_64 and AArch64 have the concept of steal/stolen
time so this test is introduced for both architectures.

While adding the test we ensure .gitignore has all tests listed
(it was missing s390x/resets) and that the Makefile has all tests
listed in alphabetical order (not really necessary, but it almost
was already...). We also extend the common API with a new num-guest-
pages call and a new timespec call.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a KVM selftest to test moving the base gfn of a userspace memory
region.  Although the basic concept of moving memory regions is not x86
specific, the assumptions regarding large pages and MMIO shenanigans
used to verify the correctness make this x86_64 only for the time being.
Reviewed-by: NPeter Xu <peterx@redhat.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add an argument to allow the demand paging test to work on larger and
smaller guest sizes.
Signed-off-by: NBen Gardon <bgardon@google.com>
[Rewrote parse_size() to simplify and provide user more flexibility as
 to how sizes are input. Also fixed size overflow assert.]
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

While userfaultfd, KVM's demand paging implementation, is not specific
to KVM, having a benchmark for its performance will be useful for
guiding performance improvements to KVM. As a first step towards creating
a userfaultfd demand paging test, create a simple memory access test,
based on dirty_log_test.
Reviewed-by: NOliver Upton <oupton@google.com>
Signed-off-by: NBen Gardon <bgardon@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

L2 guest calls vmcall and L1 checks the exit status does
correspond.
Signed-off-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NMiaohe Lin <linmiaohe@huawei.com>
Tested-by: NWei Huang <wei.huang2@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add the basic infrastructure needed to test AMD nested SVM.
This is largely copied from the KVM unit test infrastructure.
Signed-off-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Test if the registers end up having the correct values after a normal,
initial and clear reset.
Signed-off-by: NJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-6-frankja@linux.ibm.comSigned-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The kernel's version of msr-index.h was pulled wholesale into tools by
commit

  444e2ff3 ("tools arch x86: Grab a copy of the file containing the MSR numbers"),

Use the common msr-index.h instead of manually redefining everything in
a KVM-only header.

Note, a few MSR-related definitions remain in processor.h because they
are not covered by msr-index.h, including the awesomely named
APIC_BASE_MSR, which refers to starting index of the x2APIC MSRs, not
the actual MSR_IA32_APICBASE, which *is* defined by msr-index.h.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-3-sean.j.christopherson@intel.com

Ensure that IA32_XSS appears in KVM_GET_MSR_INDEX_LIST if it can be set
to a non-zero value.
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NAaron Lewis <aaronlewis@google.com>
Change-Id: Ia2d644f69e2d6d8c27d7e0a7a45c2bf9c42bf5ff
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Fix the following build error from "make TARGETS=kvm kselftest":

libkvm.a(assert.o): relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a PIE object; recompile with -fPIC

This error is seen when build is done from the main Makefile using
kselftest target. In this case KBUILD_CPPFLAGS and CC_OPTION_CFLAGS
are defined.

When build is invoked using:

"make -C tools/testing/selftests/kvm" KBUILD_CPPFLAGS and CC_OPTION_CFLAGS
aren't defined.

There is no need to pass in KBUILD_CPPFLAGS and CC_OPTION_CFLAGS for the
check to determine if --no-pie is necessary, which is the case when these
two aren't defined when "make -C tools/testing/selftests/kvm" runs.

Fix it by simplifying the no-pie-option logic. With this change, both
build variations work.

"make TARGETS=kvm kselftest"
"make -C tools/testing/selftests/kvm"
Signed-off-by: NShuah Khan <skhan@linuxfoundation.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Check that accesses by nested guests are logged according to the
L1 physical addresses rather than L2.

Most of the patch is really adding EPT support to the testing
framework.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Check that we can write and read the guest memory with this s390x
ioctl, and that some error cases are handled correctly.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Link: https://lkml.kernel.org/r/20190829130732.580-1-thuth@redhat.comSigned-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

To run the dirty_log_test on s390x, we have to make sure that we
access the dirty log bitmap with little endian byte ordering and
we have to properly align the memslot of the guest.
Also all dirty bits of a segment are set once on s390x when one
of the pages of a segment are written to for the first time, so
we have to make sure that we touch all pages during the first
iteration to keep the test in sync here.
DEFAULT_GUEST_TEST_MEM needs an adjustment, too. On some s390x
distributions, the ELF binary is linked to address 0x80000000,
so we have to avoid that our test region overlaps into this area.
0xc0000000 seems to be a good alternative that should work on x86
and aarch64, too.
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NThomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-4-thuth@redhat.comSigned-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

On s390x, we can neither exit via PIO nor MMIO, but have to use an
instruction like DIAGNOSE. Now that ucall() is implemented, we can
use it in the sync_reg_test on s390x, too.
Reviewed-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NThomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-3-thuth@redhat.comSigned-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>