kernel/linux.git/tools/testing/selftests/kvm/lib, branch v5.13.1

KVM: selftests: Fix kvm_check_cap() assertion

2021-06-17T17:06:57+00:00

KVM_CHECK_EXTENSION ioctl can return any negative value on error, and not necessarily -1. Change the assertion to reflect that. Signed-off-by: Fuad Tabba Message-Id: <20210615150443.1183365-1-tabba@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Fix compiling errors when initializing the static structure

2021-06-10T11:46:10+00:00

Errors like below were produced from test_util.c when compiling the KVM selftests on my local platform. lib/test_util.c: In function 'vm_mem_backing_src_alias': lib/test_util.c:177:12: error: initializer element is not constant .flag = anon_flags, ^~~~~~~~~~ lib/test_util.c:177:12: note: (near initialization for 'aliases[0].flag') The reason is that we are using non-const expressions to initialize the static structure, which will probably trigger a compiling error/warning on stricter GCC versions. Fix it by converting the two const variables "anon_flags" and "anon_huge_flags" into more stable macros. Fixes: b3784bc28ccc0 ("KVM: selftests: refactor vm_mem_backing_src_type flags") Reported-by: Zenghui Yu Signed-off-by: Yanan Wang Message-Id: <20210610085418.35544-1-wangyanan55@huawei.com> Signed-off-by: Paolo Bonzini

selftests: kvm: Add support for customized slot0 memory size

2021-06-08T17:29:10+00:00

Until commit 39fe2fc96694 ("selftests: kvm: make allocation of extra memory take effect", 2021-05-27), parameter extra_mem_pages was used only to calculate the page table size for all the memory chunks, because real memory allocation happened with calls of vm_userspace_mem_region_add() after vm_create_default(). Commit 39fe2fc96694 however changed the meaning of extra_mem_pages to the size of memory slot 0. This makes the memory allocation more flexible, but makes it harder to account for the number of pages needed for the page tables. For example, memslot_perf_test has a small amount of memory in slot 0 but a lot in other slots, and adding that memory twice (both in slot 0 and with later calls to vm_userspace_mem_region_add()) causes an error that was fixed in commit 000ac4295339 ("selftests: kvm: fix overlapping addresses in memslot_perf_test", 2021-05-29) Since both uses are sensible, add a new parameter slot0_mem_pages to vm_create_with_vcpus() and some comments to clarify the meaning of slot0_mem_pages and extra_mem_pages. With this change, memslot_perf_test can go back to passing the number of memory pages as extra_mem_pages. Signed-off-by: Zhenzhong Duan Message-Id: <20210608233816.423958-4-zhenzhong.duan@intel.com> [Squashed in a single patch and rewrote the commit message. - Paolo] Signed-off-by: Paolo Bonzini

KVM: selftests: introduce P47V64 for s390x

2021-06-08T17:19:19+00:00

s390x can have up to 47bits of physical guest and 64bits of virtual address bits. Add a new address mode to avoid errors of testcases going beyond 47bits. Signed-off-by: Christian Borntraeger Message-Id: <20210608123954.10991-1-borntraeger@de.ibm.com> Fixes: ef4c9f4f6546 ("KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn()") Cc: stable@vger.kernel.org Reviewed-by: David Matlack Signed-off-by: Paolo Bonzini

KVM: selftests: add shared hugetlbfs backing source type

2021-05-27T11:45:57+00:00

This lets us run the demand paging test on top of a shared hugetlbfs-backed area. The "shared" is key, as this allows us to exercise userfaultfd minor faults on hugetlbfs. Signed-off-by: Axel Rasmussen Message-Id: <20210519200339.829146-11-axelrasmussen@google.com> Reviewed-by: Ben Gardon Signed-off-by: Paolo Bonzini

KVM: selftests: create alias mappings when using shared memory

2021-05-27T11:45:56+00:00

When a memory region is added with a src_type specifying that it should use some kind of shared memory, also create an alias mapping to the same underlying physical pages. And, add an API so tests can get access to these alias addresses. Basically, for a guest physical address, let us look up the analogous host *alias* address. In a future commit, we'll modify the demand paging test to take advantage of this to exercise UFFD minor faults. The idea is, we pre-fault the underlying pages *via the alias*. When the *guest* faults, it gets a "minor" fault (PTEs don't exist yet, but a page is already in the page cache). Then, the userfaultfd theads can handle the fault: they could potentially modify the underlying memory *via the alias* if they wanted to, and then they install the PTEs and let the guest carry on via a UFFDIO_CONTINUE ioctl. Reviewed-by: Ben Gardon Signed-off-by: Axel Rasmussen Message-Id: <20210519200339.829146-9-axelrasmussen@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: add shmem backing source type

2021-05-27T11:45:56+00:00

This lets us run the demand paging test on top of a shmem-backed area. In follow-up commits, we'll 1) leverage this new capability to create an alias mapping, and then 2) use the alias mapping to exercise UFFD minor faults. Signed-off-by: Axel Rasmussen Message-Id: <20210519200339.829146-8-axelrasmussen@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: refactor vm_mem_backing_src_type flags

2021-05-27T11:45:56+00:00

Each struct vm_mem_backing_src_alias has a flags field, which denotes the flags used to mmap() an area of that type. Previously, this field never included MAP_PRIVATE | MAP_ANONYMOUS, because vm_userspace_mem_region_add assumed that *all* types would always use those flags, and so it hardcoded them. In a follow-up commit, we'll add a new type: shmem. Areas of this type must not have MAP_PRIVATE | MAP_ANONYMOUS, and instead they must have MAP_SHARED. So, refactor things. Make it so that the flags field of struct vm_mem_backing_src_alias really is a complete set of flags, and don't add in any extras in vm_userspace_mem_region_add. This will let us easily tack on shmem. Signed-off-by: Axel Rasmussen Message-Id: <20210519200339.829146-7-axelrasmussen@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Print a message if /dev/kvm is missing

2021-05-27T11:45:55+00:00

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 Message-Id: <20210511202120.1371800-1-dmatlack@google.com> Signed-off-by: Paolo Bonzini

KVM: selftests: trivial comment/logging fixes

2021-05-27T11:45:55+00:00

Some trivial fixes I found while touching related code in this series, factored out into a separate commit for easier reviewing: - s/gor/got/ and add a newline in demand_paging_test.c - s/backing_src/src_type/ in a comment to be consistent with the real function signature in kvm_util.c Signed-off-by: Axel Rasmussen Message-Id: <20210519200339.829146-2-axelrasmussen@google.com> Reviewed-by: Ben Gardon Signed-off-by: Paolo Bonzini