Searched +hist:2 +hist:aab4b35 (Results 1 - 4 of 4) sorted by relevance

/linux-master/tools/testing/selftests/kvm/x86_64/
H A Dget_msr_index_features.cdiff 2aab4b35 Tue May 11 14:21:20 MDT 2021 David Matlack <dmatlack@google.com> KVM: selftests: Print a message if /dev/kvm is missing

If a KVM selftest is run on a machine without /dev/kvm, it will exit
silently. Make it easy to tell what's happening by printing an error
message.

Opportunistically consolidate all codepaths that open /dev/kvm into a
single function so they all print the same message.

This slightly changes the semantics of vm_is_unrestricted_guest() by
changing a TEST_ASSERT() to exit(KSFT_SKIP). However
vm_is_unrestricted_guest() is only called in one place
(x86_64/mmio_warning_test.c) and that is to determine if the test should
be skipped or not.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210511202120.1371800-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2aab4b35 Tue May 11 14:21:20 MDT 2021 David Matlack <dmatlack@google.com> KVM: selftests: Print a message if /dev/kvm is missing

If a KVM selftest is run on a machine without /dev/kvm, it will exit
silently. Make it easy to tell what's happening by printing an error
message.

Opportunistically consolidate all codepaths that open /dev/kvm into a
single function so they all print the same message.

This slightly changes the semantics of vm_is_unrestricted_guest() by
changing a TEST_ASSERT() to exit(KSFT_SKIP). However
vm_is_unrestricted_guest() is only called in one place
(x86_64/mmio_warning_test.c) and that is to determine if the test should
be skipped or not.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210511202120.1371800-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
/linux-master/tools/testing/selftests/kvm/include/
H A Dkvm_util.hdiff 7d9a662e Fri Dec 10 09:46:11 MST 2021 Michael Roth <michael.roth@amd.com> kvm: selftests: move base kvm_util.h declarations to kvm_util_base.h

Between helper macros and interfaces that will be introduced in
subsequent patches, much of kvm_util.h would end up being declarations
specific to ucall. Ideally these could be separated out into a separate
header since they are not strictly required for writing guest tests and
are mostly self-contained interfaces other than a reliance on a few
core declarations like struct kvm_vm. This doesn't make a big
difference as far as how tests will be compiled/written since all these
interfaces will still be packaged up into a single/common libkvm.a used
by all tests, but it is still nice to be able to compartmentalize to
improve readabilty and reduce merge conflicts in the future for common
tasks like adding new interfaces to kvm_util.h.

Furthermore, some of the ucall declarations will be arch-specific,
requiring various #ifdef'ery in kvm_util.h. Ideally these declarations
could live in separate arch-specific headers, e.g.
include/<arch>/ucall.h, which would handle arch-specific declarations
as well as pulling in common ucall-related declarations shared by all
archs.

One simple way to do this would be to #include ucall.h at the bottom of
kvm_util.h, after declarations it relies upon like struct kvm_vm.
This is brittle however, and doesn't scale easily to other sets of
interfaces that may be added in the future.

Instead, move all declarations currently in kvm_util.h into
kvm_util_base.h, then have kvm_util.h #include it. With this change,
non-base declarations can be selectively moved/introduced into separate
headers, which can then be included in kvm_util.h so that individual
tests don't need to be touched. Subsequent patches will then move
ucall-related declarations into a separate header to meet the above
goals.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Message-Id: <20211210164620.11636-2-michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff c8cc43c1 Thu Aug 05 04:54:23 MDT 2021 Paolo Bonzini <pbonzini@redhat.com> selftests: KVM: avoid failures due to reserved HyperTransport region

AMD proceessors define an address range that is reserved by HyperTransport
and causes a failure if used for guest physical addresses. Avoid
selftests failures by reserving those guest physical addresses; the
rules are:

- On parts with <40 bits, its fully hidden from software.

- Before Fam17h, it was always 12G just below 1T, even if there was more
RAM above this location. In this case we just not use any RAM above 1T.

- On Fam17h and later, it is variable based on SME, and is either just
below 2^48 (no encryption) or 2^43 (encryption).

Fixes: ef4c9f4f6546 ("KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn()")
Cc: stable@vger.kernel.org
Cc: David Matlack <dmatlack@google.com>
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210805105423.412878-1-pbonzini@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff c8cc43c1 Thu Aug 05 04:54:23 MDT 2021 Paolo Bonzini <pbonzini@redhat.com> selftests: KVM: avoid failures due to reserved HyperTransport region

AMD proceessors define an address range that is reserved by HyperTransport
and causes a failure if used for guest physical addresses. Avoid
selftests failures by reserving those guest physical addresses; the
rules are:

- On parts with <40 bits, its fully hidden from software.

- Before Fam17h, it was always 12G just below 1T, even if there was more
RAM above this location. In this case we just not use any RAM above 1T.

- On Fam17h and later, it is variable based on SME, and is either just
below 2^48 (no encryption) or 2^43 (encryption).

Fixes: ef4c9f4f6546 ("KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn()")
Cc: stable@vger.kernel.org
Cc: David Matlack <dmatlack@google.com>
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210805105423.412878-1-pbonzini@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2aab4b35 Tue May 11 14:21:20 MDT 2021 David Matlack <dmatlack@google.com> KVM: selftests: Print a message if /dev/kvm is missing

If a KVM selftest is run on a machine without /dev/kvm, it will exit
silently. Make it easy to tell what's happening by printing an error
message.

Opportunistically consolidate all codepaths that open /dev/kvm into a
single function so they all print the same message.

This slightly changes the semantics of vm_is_unrestricted_guest() by
changing a TEST_ASSERT() to exit(KSFT_SKIP). However
vm_is_unrestricted_guest() is only called in one place
(x86_64/mmio_warning_test.c) and that is to determine if the test should
be skipped or not.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210511202120.1371800-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2aab4b35 Tue May 11 14:21:20 MDT 2021 David Matlack <dmatlack@google.com> KVM: selftests: Print a message if /dev/kvm is missing

If a KVM selftest is run on a machine without /dev/kvm, it will exit
silently. Make it easy to tell what's happening by printing an error
message.

Opportunistically consolidate all codepaths that open /dev/kvm into a
single function so they all print the same message.

This slightly changes the semantics of vm_is_unrestricted_guest() by
changing a TEST_ASSERT() to exit(KSFT_SKIP). However
vm_is_unrestricted_guest() is only called in one place
(x86_64/mmio_warning_test.c) and that is to determine if the test should
be skipped or not.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210511202120.1371800-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 84292e56 Wed Sep 30 19:22:37 MDT 2020 Peter Xu <peterx@redhat.com> KVM: selftests: Add dirty ring buffer test

Add the initial dirty ring buffer test.

The current test implements the userspace dirty ring collection, by
only reaping the dirty ring when the ring is full.

So it's still running synchronously like this:

vcpu main thread

1. vcpu dirties pages
2. vcpu gets dirty ring full
(userspace exit)

3. main thread waits until full
(so hardware buffers flushed)
4. main thread collects
5. main thread continues vcpu

6. vcpu continues, goes back to 1

We can't directly collects dirty bits during vcpu execution because
otherwise we can't guarantee the hardware dirty bits were flushed when
we collect and we're very strict on the dirty bits so otherwise we can
fail the future verify procedure. A follow up patch will make this
test to support async just like the existing dirty log test, by adding
a vcpu kick mechanism.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201001012237.6111-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2040f414 Wed Jul 31 09:15:23 MDT 2019 Thomas Huth <thuth@redhat.com> KVM: selftests: Split ucall.c into architecture specific files

The way we exit from a guest to userspace is very specific to the
architecture: On x86, we use PIO, on aarch64 we are using MMIO and on
s390x we're going to use an instruction instead. The possibility to
select a type via the ucall_type_t enum is currently also completely
unused, so the code in ucall.c currently looks more complex than
required. Let's split this up into architecture specific ucall.c
files instead, so we can get rid of the #ifdefs and the unnecessary
ucall_type_t handling.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-2-thuth@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diff 7a338472 Tue Jun 04 02:11:15 MDT 2019 Thomas Gleixner <tglx@linutronix.de> treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482

Based on 1 normalized pattern(s):

this work is licensed under the terms of the gnu gpl version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 48 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081204.624030236@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 2a31b9db Mon Oct 22 18:36:47 MDT 2018 Paolo Bonzini <pbonzini@redhat.com> kvm: introduce manual dirty log reprotect

There are two problems with KVM_GET_DIRTY_LOG. First, and less important,
it can take kvm->mmu_lock for an extended period of time. Second, its user
can actually see many false positives in some cases. The latter is due
to a benign race like this:

1. KVM_GET_DIRTY_LOG returns a set of dirty pages and write protects
them.
2. The guest modifies the pages, causing them to be marked ditry.
3. Userspace actually copies the pages.
4. KVM_GET_DIRTY_LOG returns those pages as dirty again, even though
they were not written to since (3).

This is especially a problem for large guests, where the time between
(1) and (3) can be substantial. This patch introduces a new
capability which, when enabled, makes KVM_GET_DIRTY_LOG not
write-protect the pages it returns. Instead, userspace has to
explicitly clear the dirty log bits just before using the content
of the page. The new KVM_CLEAR_DIRTY_LOG ioctl can also operate on a
64-page granularity rather than requiring to sync a full memslot;
this way, the mmu_lock is taken for small amounts of time, and
only a small amount of time will pass between write protection
of pages and the sending of their content.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2a31b9db Mon Oct 22 18:36:47 MDT 2018 Paolo Bonzini <pbonzini@redhat.com> kvm: introduce manual dirty log reprotect

There are two problems with KVM_GET_DIRTY_LOG. First, and less important,
it can take kvm->mmu_lock for an extended period of time. Second, its user
can actually see many false positives in some cases. The latter is due
to a benign race like this:

1. KVM_GET_DIRTY_LOG returns a set of dirty pages and write protects
them.
2. The guest modifies the pages, causing them to be marked ditry.
3. Userspace actually copies the pages.
4. KVM_GET_DIRTY_LOG returns those pages as dirty again, even though
they were not written to since (3).

This is especially a problem for large guests, where the time between
(1) and (3) can be substantial. This patch introduces a new
capability which, when enabled, makes KVM_GET_DIRTY_LOG not
write-protect the pages it returns. Instead, userspace has to
explicitly clear the dirty log bits just before using the content
of the page. The new KVM_CLEAR_DIRTY_LOG ioctl can also operate on a
64-page granularity rather than requiring to sync a full memslot;
this way, the mmu_lock is taken for small amounts of time, and
only a small amount of time will pass between write protection
of pages and the sending of their content.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
/linux-master/tools/testing/selftests/kvm/lib/x86_64/
H A Dprocessor.cdiff e440c5f2 Tue Jan 09 07:11:17 MST 2024 Vitaly Kuznetsov <vkuznets@redhat.com> KVM: selftests: Generalize check_clocksource() from kvm_clock_test

Several existing x86 selftests need to check that the underlying system
clocksource is TSC or based on TSC but every test implements its own
check. As a first step towards unification, extract check_clocksource()
from kvm_clock_test and split it into two functions: arch-neutral
'sys_get_cur_clocksource()' and x86-specific 'sys_clocksource_is_tsc()'.
Fix a couple of pre-existing issues in kvm_clock_test: memory leakage in
check_clocksource() and using TEST_ASSERT() instead of TEST_REQUIRE().
The change also makes the test fail when system clocksource can't be read
from sysfs.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240109141121.1619463-2-vkuznets@redhat.com
[sean: eliminate if-elif pattern just to set a bool true]
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff 4009e0bb Fri Feb 03 19:41:48 MST 2023 Sean Christopherson <seanjc@google.com> KVM: selftests: Move the guts of kvm_hypercall() to a separate macro

Extract the guts of kvm_hypercall() to a macro so that Xen hypercalls,
which have a different register ABI, can reuse the VMCALL vs. VMMCALL
logic.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230204024151.1373296-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff e99b0d4c Tue Jan 10 17:44:43 MST 2023 Vishal Annapurve <vannapurve@google.com> KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries

Replace is_intel/amd_cpu helpers with this_cpu_* helpers to better
convey the intent of querying vendor of the current cpu.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
Link: https://lore.kernel.org/r/20230111004445.416840-2-vannapurve@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff 2ceade1d Mon Nov 28 15:57:33 MST 2022 Sean Christopherson <seanjc@google.com> KVM: selftests: Move __vm_xsave_require_permission() below CPUID helpers

Move __vm_xsave_require_permission() below the CPUID helpers so that a
future change can reference the cached result of KVM_GET_SUPPORTED_CPUID
while keeping the definition of the variable close to its intended user,
kvm_get_supported_cpuid().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221128225735.3291648-3-seanjc@google.com
diff 18eee7bf Mon Nov 28 15:57:32 MST 2022 Lei Wang <lei4.wang@intel.com> KVM: selftests: Move XFD CPUID checking out of __vm_xsave_require_permission()

Move the kvm_cpu_has() check on X86_FEATURE_XFD out of the helper to
enable off-by-default XSAVE-managed features and into the one test that
currenty requires XFD (XFeature Disable) support. kvm_cpu_has() uses
kvm_get_supported_cpuid() and thus caches KVM_GET_SUPPORTED_CPUID, and so
using kvm_cpu_has() before ARCH_REQ_XCOMP_GUEST_PERM effectively results
in the test caching stale values, e.g. subsequent checks on AMX_TILE will
get false negatives.

Although off-by-default features are nonsensical without XFD, checking
for XFD virtualization prior to enabling such features isn't strictly
required.

Signed-off-by: Lei Wang <lei4.wang@intel.com>
Fixes: 7fbb653e01fd ("KVM: selftests: Check KVM's supported CPUID, not host CPUID, for XFD")
Link: https://lore.kernel.org/r/20221125023839.315207-1-lei4.wang@intel.com
[sean: add Fixes, reword changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221128225735.3291648-2-seanjc@google.com
diff 3bd39635 Wed Oct 05 18:51:14 MDT 2022 Sean Christopherson <seanjc@google.com> KVM: selftests: Add X86_FEATURE_PAE and use it calc "fallback" MAXPHYADDR

Add X86_FEATURE_PAE and use it to guesstimate the MAXPHYADDR when the
MAXPHYADDR CPUID entry isn't supported.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-2-seanjc@google.com
diff 816c54b7 Wed Oct 05 18:45:06 MDT 2022 Sean Christopherson <seanjc@google.com> KVM: selftests: Drop helpers to read/write page table entries

Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
PTE, i.e. let tests directly modify PTEs instead of bouncing through
helpers that just make life difficult.

Opportunsitically use BIT_ULL() in emulator_error_test, and use the
MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
same value.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-2-seanjc@google.com
diff 458e9874 Thu Sep 29 12:12:07 MDT 2022 David Matlack <dmatlack@google.com> KVM: selftests: Fix nx_huge_pages_test on TDP-disabled hosts

Map the test's huge page region with 2MiB virtual mappings when TDP is
disabled so that KVM can shadow the region with huge pages. This fixes
nx_huge_pages_test on hosts where TDP hardware support is disabled.

Purposely do not skip this test on TDP-disabled hosts. While we don't
care about NX Huge Pages on TDP-disabled hosts from a security
perspective, KVM does support it, and so we should test it.

For TDP-enabled hosts, continue mapping the region with 4KiB pages to
ensure that KVM can map it with huge pages irrespective of the guest
mappings.

Fixes: 8448ec5993be ("KVM: selftests: Add NX huge pages test")
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220929181207.2281449-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 4c16fa3e Tue Jun 14 14:06:26 MDT 2022 Sean Christopherson <seanjc@google.com> KVM: selftests: Set KVM's supported CPUID as vCPU's CPUID during recreate

On x86-64, set KVM's supported CPUID as the vCPU's CPUID when recreating
a VM+vCPU to deduplicate code for state save/restore tests, and to
provide symmetry of sorts with respect to vm_create_with_one_vcpu(). The
extra KVM_SET_CPUID2 call is wasteful for Hyper-V, but ultimately is
nothing more than an expensive nop, and overriding the vCPU's CPUID with
the Hyper-V CPUID information is the only known scenario where a state
save/restore test wouldn't need/want the default CPUID.

Opportunistically use __weak for the default vm_compute_max_gfn(), it's
provided by tools' compiler.h.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-2-seanjc@google.com
diff 4ee602e7 Fri May 20 17:32:39 MDT 2022 David Matlack <dmatlack@google.com> KVM: selftests: Replace x86_page_size with PG_LEVEL_XX

x86_page_size is an enum used to communicate the desired page size with
which to map a range of memory. Under the hood they just encode the
desired level at which to map the page. This ends up being clunky in a
few ways:

- The name suggests it encodes the size of the page rather than the
level.
- In other places in x86_64/processor.c we just use a raw int to encode
the level.

Simplify this by adopting the kernel style of PG_LEVEL_XX enums and pass
around raw ints when referring to the level. This makes the code easier
to understand since these macros are very common in KVM MMU code.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220520233249.3776001-2-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
/linux-master/tools/testing/selftests/kvm/lib/
H A Dkvm_util.cdiff 12619037 Thu Feb 22 17:42:48 MST 2024 Sean Christopherson <seanjc@google.com> KVM: selftests: Extend VM creation's @shape to allow control of VM subtype

Carve out space in the @shape passed to the various VM creation helpers to
allow using the shape to control the subtype of VM, e.g. to identify x86's
SEV VMs (which are "regular" VMs as far as KVM is concerned).

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vishal Annapurve <vannapurve@google.com>
Cc: Ackerley Tng <ackerleytng@google.com>
Cc: Andrew Jones <andrew.jones@linux.dev>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Michael Roth <michael.roth@amd.com>
Tested-by: Carlos Bilbao <carlos.bilbao@amd.com>
Link: https://lore.kernel.org/r/20240223004258.3104051-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff c2a449a3 Mon Jan 29 01:58:47 MST 2024 Vitaly Kuznetsov <vkuznets@redhat.com> KVM: selftests: Fail tests when open() fails with !ENOENT

open_path_or_exit() is used for '/dev/kvm', '/dev/sev', and
'/sys/module/%s/parameters/%s' and skipping test when the entry is missing
is completely reasonable. Other errors, however, may indicate a real issue
which is easy to miss. E.g. when 'hyperv_features' test was entering an
infinite loop the output was:

./hyperv_features
Testing access to Hyper-V specific MSRs
1..0 # SKIP - /dev/kvm not available (errno: 24)

and this can easily get overlooked.

Keep ENOENT case 'special' for skipping tests and fail when open() results
in any other errno.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240129085847.2674082-2-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff 1b78d474 Tue Nov 07 18:09:53 MST 2023 Sean Christopherson <seanjc@google.com> KVM: selftests: Add logic to detect if ioctl() failed because VM was killed

Add yet another macro to the VM/vCPU ioctl() framework to detect when an
ioctl() failed because KVM killed/bugged the VM, i.e. when there was
nothing wrong with the ioctl() itself. If KVM kills a VM, e.g. by way of
a failed KVM_BUG_ON(), all subsequent VM and vCPU ioctl()s will fail with
-EIO, which can be quite misleading and ultimately waste user/developer
time.

Use KVM_CHECK_EXTENSION on KVM_CAP_USER_MEMORY to detect if the VM is
dead and/or bug, as KVM doesn't provide a dedicated ioctl(). Using a
heuristic is obviously less than ideal, but practically speaking the logic
is bulletproof barring a KVM change, and any such change would arguably
break userspace, e.g. if KVM returns something other than -EIO.

Without the detection, tearing down a bugged VM yields a cryptic failure
when deleting memslots:

==== Test Assertion Failure ====
lib/kvm_util.c:689: !ret
pid=45131 tid=45131 errno=5 - Input/output error
1 0x00000000004036c3: __vm_mem_region_delete at kvm_util.c:689
2 0x00000000004042f0: kvm_vm_free at kvm_util.c:724 (discriminator 12)
3 0x0000000000402929: race_sync_regs at sync_regs_test.c:193
4 0x0000000000401cab: main at sync_regs_test.c:334 (discriminator 6)
5 0x0000000000416f13: __libc_start_call_main at libc-start.o:?
6 0x000000000041855f: __libc_start_main_impl at ??:?
7 0x0000000000401d40: _start at ??:?
KVM_SET_USER_MEMORY_REGION failed, rc: -1 errno: 5 (Input/output error)

Which morphs into a more pointed error message with the detection:

==== Test Assertion Failure ====
lib/kvm_util.c:689: false
pid=80347 tid=80347 errno=5 - Input/output error
1 0x00000000004039ab: __vm_mem_region_delete at kvm_util.c:689 (discriminator 5)
2 0x0000000000404660: kvm_vm_free at kvm_util.c:724 (discriminator 12)
3 0x0000000000402ac9: race_sync_regs at sync_regs_test.c:193
4 0x0000000000401cb7: main at sync_regs_test.c:334 (discriminator 6)
5 0x0000000000418263: __libc_start_call_main at libc-start.o:?
6 0x00000000004198af: __libc_start_main_impl at ??:?
7 0x0000000000401d90: _start at ??:?
KVM killed/bugged the VM, check the kernel log for clues

Suggested-by: Michal Luczaj <mhal@rbox.co>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Colton Lewis <coltonlewis@google.com>
Link: https://lore.kernel.org/r/20231108010953.560824-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff 1b78d474 Tue Nov 07 18:09:53 MST 2023 Sean Christopherson <seanjc@google.com> KVM: selftests: Add logic to detect if ioctl() failed because VM was killed

Add yet another macro to the VM/vCPU ioctl() framework to detect when an
ioctl() failed because KVM killed/bugged the VM, i.e. when there was
nothing wrong with the ioctl() itself. If KVM kills a VM, e.g. by way of
a failed KVM_BUG_ON(), all subsequent VM and vCPU ioctl()s will fail with
-EIO, which can be quite misleading and ultimately waste user/developer
time.

Use KVM_CHECK_EXTENSION on KVM_CAP_USER_MEMORY to detect if the VM is
dead and/or bug, as KVM doesn't provide a dedicated ioctl(). Using a
heuristic is obviously less than ideal, but practically speaking the logic
is bulletproof barring a KVM change, and any such change would arguably
break userspace, e.g. if KVM returns something other than -EIO.

Without the detection, tearing down a bugged VM yields a cryptic failure
when deleting memslots:

==== Test Assertion Failure ====
lib/kvm_util.c:689: !ret
pid=45131 tid=45131 errno=5 - Input/output error
1 0x00000000004036c3: __vm_mem_region_delete at kvm_util.c:689
2 0x00000000004042f0: kvm_vm_free at kvm_util.c:724 (discriminator 12)
3 0x0000000000402929: race_sync_regs at sync_regs_test.c:193
4 0x0000000000401cab: main at sync_regs_test.c:334 (discriminator 6)
5 0x0000000000416f13: __libc_start_call_main at libc-start.o:?
6 0x000000000041855f: __libc_start_main_impl at ??:?
7 0x0000000000401d40: _start at ??:?
KVM_SET_USER_MEMORY_REGION failed, rc: -1 errno: 5 (Input/output error)

Which morphs into a more pointed error message with the detection:

==== Test Assertion Failure ====
lib/kvm_util.c:689: false
pid=80347 tid=80347 errno=5 - Input/output error
1 0x00000000004039ab: __vm_mem_region_delete at kvm_util.c:689 (discriminator 5)
2 0x0000000000404660: kvm_vm_free at kvm_util.c:724 (discriminator 12)
3 0x0000000000402ac9: race_sync_regs at sync_regs_test.c:193
4 0x0000000000401cb7: main at sync_regs_test.c:334 (discriminator 6)
5 0x0000000000418263: __libc_start_call_main at libc-start.o:?
6 0x00000000004198af: __libc_start_main_impl at ??:?
7 0x0000000000401d90: _start at ??:?
KVM killed/bugged the VM, check the kernel log for clues

Suggested-by: Michal Luczaj <mhal@rbox.co>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Colton Lewis <coltonlewis@google.com>
Link: https://lore.kernel.org/r/20231108010953.560824-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff e6f4f345 Fri Oct 27 12:22:14 MDT 2023 Chao Peng <chao.p.peng@linux.intel.com> KVM: selftests: Add KVM_SET_USER_MEMORY_REGION2 helper

Add helpers to invoke KVM_SET_USER_MEMORY_REGION2 directly so that tests
can validate of features that are unique to "version 2" of "set user
memory region", e.g. do negative testing on gmem_fd and gmem_offset.

Provide a raw version as well as an assert-success version to reduce
the amount of boilerplate code need for basic usage.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20231027182217.3615211-33-seanjc@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 6d85f51a Wed Jul 12 01:59:07 MDT 2023 Thomas Huth <thuth@redhat.com> KVM: selftests: Rename the ASSERT_EQ macro

There is already an ASSERT_EQ macro in the file
tools/testing/selftests/kselftest_harness.h, so currently KVM selftests
can't include test_util.h from the KVM selftests together with that file.
Rename the macro in the KVM selftests to TEST_ASSERT_EQ to avoid the
problem - it is also more similar to the other macros in test_util.h that
way.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/20230712075910.22480-2-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff d14d9139 Tue Feb 14 01:49:19 MST 2023 Like Xu <likexu@tencent.com> KVM: selftests: Add a helper to read kvm boolean module parameters

Add a helper function for reading kvm boolean module parameters values.
No functional change intended.

Signed-off-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20230214084920.59787-2-likexu@tencent.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff e8b9a055 Wed Dec 07 14:48:07 MST 2022 Oliver Upton <oliver.upton@linux.dev> KVM: arm64: selftests: Align VA space allocator with TTBR0

An interesting feature of the Arm architecture is that the stage-1 MMU
supports two distinct VA regions, controlled by TTBR{0,1}_EL1. As KVM
selftests on arm64 only uses TTBR0_EL1, the VA space is constrained to
[0, 2^(va_bits-1)). This is different from other architectures that
allow for addressing low and high regions of the VA space from a single
page table.

KVM selftests' VA space allocator presumes the valid address range is
split between low and high memory based the MSB, which of course is a
poor match for arm64's TTBR0 region.

Allow architectures to override the default VA space layout. Make use of
the override to align vpages_valid with the behavior of TTBR0 on arm64.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Message-Id: <20221207214809.489070-4-oliver.upton@linux.dev>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 2d4a5f91 Tue Nov 01 08:54:13 MDT 2022 Vitaly Kuznetsov <vkuznets@redhat.com> KVM: selftests: Export vm_vaddr_unused_gap() to make it possible to request unmapped ranges

Currently, tests can only request a new vaddr range by using
vm_vaddr_alloc()/vm_vaddr_alloc_page()/vm_vaddr_alloc_pages() but
these functions allocate and map physical pages too. Make it possible
to request unmapped range too.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-36-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff 197ebb71 Tue Nov 15 14:38:43 MST 2022 Vishal Annapurve <vannapurve@google.com> KVM: selftests: move common startup logic to kvm_util.c

Consolidate common startup logic in one place by implementing a single
setup function with __attribute((constructor)) for all selftests within
kvm_util.c.

This allows moving logic like:
/* Tell stdout not to buffer its content */
setbuf(stdout, NULL);
to a single file for all selftests.

This will also allow any required setup at entry in future to be done in
common main function.

Link: https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
Link: https://lore.kernel.org/r/20221115213845.3348210-2-vannapurve@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
diff 197ebb71 Tue Nov 15 14:38:43 MST 2022 Vishal Annapurve <vannapurve@google.com> KVM: selftests: move common startup logic to kvm_util.c

Consolidate common startup logic in one place by implementing a single
setup function with __attribute((constructor)) for all selftests within
kvm_util.c.

This allows moving logic like:
/* Tell stdout not to buffer its content */
setbuf(stdout, NULL);
to a single file for all selftests.

This will also allow any required setup at entry in future to be done in
common main function.

Link: https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
Link: https://lore.kernel.org/r/20221115213845.3348210-2-vannapurve@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Completed in 382 milliseconds