summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/kvm/max_guest_memory_test.c
AgeCommit message (Collapse)Author
2024-12-18KVM: selftests: Rename max_guest_memory_test to mmu_stress_testSean Christopherson
Rename max_guest_memory_test to mmu_stress_test so that the name isn't horribly misleading when future changes extend the test to verify things like mprotect() interactions, and because the test is useful even when its configured to populate far less than the maximum amount of guest memory. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-05-12Merge tag 'kvm-x86-selftests_utils-6.10' of https://github.com/kvm-x86/linux ↵Paolo Bonzini
into HEAD KVM selftests treewide updates for 6.10: - Define _GNU_SOURCE for all selftests to fix a warning that was introduced by a change to kselftest_harness.h late in the 6.9 cycle, and because forcing every test to #define _GNU_SOURCE is painful. - Provide a global psuedo-RNG instance for all tests, so that library code can generate random, but determinstic numbers. - Use the global pRNG to randomly force emulation of select writes from guest code on x86, e.g. to help validate KVM's emulation of locked accesses. - Rename kvm_util_base.h back to kvm_util.h, as the weird layer of indirection was added purely to avoid manually #including ucall_common.h in a handful of locations. - Allocate and initialize x86's GDT, IDT, TSS, segments, and default exception handlers at VM creation, instead of forcing tests to manually trigger the related setup.
2024-04-29KVM: selftests: Define _GNU_SOURCE for all selftests codeSean Christopherson
Define _GNU_SOURCE is the base CFLAGS instead of relying on selftests to manually #define _GNU_SOURCE, which is repetitive and error prone. E.g. kselftest_harness.h requires _GNU_SOURCE for asprintf(), but if a selftest includes kvm_test_harness.h after stdio.h, the include guards result in the effective version of stdio.h consumed by kvm_test_harness.h not defining asprintf(): In file included from x86_64/fix_hypercall_test.c:12: In file included from include/kvm_test_harness.h:11: ../kselftest_harness.h:1169:2: error: call to undeclared function 'asprintf'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] 1169 | asprintf(&test_name, "%s%s%s.%s", f->name, | ^ When including the rseq selftest's "library" code, #undef _GNU_SOURCE so that rseq.c controls whether or not it wants to build with _GNU_SOURCE. Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Acked-by: Anup Patel <anup@brainfault.org> Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20240423190308.2883084-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-04-08KVM: selftests: fix max_guest_memory_test with more that 256 vCPUsMaxim Levitsky
max_guest_memory_test uses ucalls to sync with the host, but it also resets the guest RIP back to its initial value in between tests stages. This makes the guest never reach the code which frees the ucall struct and since a fixed pool of 512 ucall structs is used, the test starts to fail when more that 256 vCPUs are used. Fix that by replacing the manual register reset with a loop in the guest code. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Link: https://lore.kernel.org/r/20240315143507.102629-1-mlevitsk@redhat.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-02KVM: selftests: Rename the ASSERT_EQ macroThomas Huth
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>
2022-11-16KVM: selftests: Add atoi_positive() and atoi_non_negative() for input validationVipin Sharma
Many KVM selftests take command line arguments which are supposed to be positive (>0) or non-negative (>=0). Some tests do these validation and some missed adding the check. Add atoi_positive() and atoi_non_negative() to validate inputs in selftests before proceeding to use those values. Signed-off-by: Vipin Sharma <vipinsh@google.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20221103191719.1559407-7-vipinsh@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16KVM: selftests: Use SZ_* macros from sizes.h in max_guest_memory_test.cVipin Sharma
Replace size_1gb defined in max_guest_memory_test.c with the SZ_1G, SZ_2G and SZ_4G from linux/sizes.h header file. Signed-off-by: Vipin Sharma <vipinsh@google.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20221103191719.1559407-5-vipinsh@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16KVM: selftests: Add atoi_paranoid() to catch errors missed by atoi()Vipin Sharma
atoi() doesn't detect errors. There is no way to know that a 0 return is correct conversion or due to an error. Introduce atoi_paranoid() to detect errors and provide correct conversion. Replace all atoi() calls with atoi_paranoid(). Signed-off-by: Vipin Sharma <vipinsh@google.com> Suggested-by: David Matlack <dmatlack@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20221103191719.1559407-4-vipinsh@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-06-11KVM: selftests: Open code and drop 'struct kvm_vm' accessorsSean Christopherson
Drop a variety of 'struct kvm_vm' accessors that wrap a single variable now that tests can simply reference the variable directly. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11KVM: selftests: Purge vm+vcpu_id == vcpu sillinessSean Christopherson
Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers and ioctls. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11KVM: selftests: Use vm_create_with_vcpus() in max_guest_memory_testSean Christopherson
Use vm_create_with_vcpus() in max_guest_memory_test and reference vCPUs by their 'struct kvm_vcpu' object instead of their ID. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-09KVM: selftests: Replace x86_page_size with PG_LEVEL_XXDavid Matlack
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>
2022-03-08KVM: selftests: Add test to populate a VM with the max possible guest memSean Christopherson
Add a selftest that enables populating a VM with the maximum amount of guest memory allowed by the underlying architecture. Abuse KVM's memslots by mapping a single host memory region into multiple memslots so that the selftest doesn't require a system with terabytes of RAM. Default to 512gb of guest memory, which isn't all that interesting, but should work on all MMUs and doesn't take an exorbitant amount of memory or time. E.g. testing with ~64tb of guest memory takes the better part of an hour, and requires 200gb of memory for KVM's page tables when using 4kb pages. To inflicit maximum abuse on KVM' MMU, default to 4kb pages (or whatever the not-hugepage size is) in the backing store (memfd). Use memfd for the host backing store to ensure that hugepages are guaranteed when requested, and to give the user explicit control of the size of hugepage being tested. By default, spin up as many vCPUs as there are available to the selftest, and distribute the work of dirtying each 4kb chunk of memory across all vCPUs. Dirtying guest memory forces KVM to populate its page tables, and also forces KVM to write back accessed/dirty information to struct page when the guest memory is freed. On x86, perform two passes with a MMU context reset between each pass to coerce KVM into dropping all references to the MMU root, e.g. to emulate a vCPU dropping the last reference. Perform both passes and all rendezvous on all architectures in the hope that arm64 and s390x can gain similar shenanigans in the future. Measure and report the duration of each operation, which is helpful not only to verify the test is working as intended, but also to easily evaluate the performance differences different page sizes. Provide command line options to limit the amount of guest memory, set the size of each slot (i.e. of the host memory region), set the number of vCPUs, and to enable usage of hugepages. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220226001546.360188-29-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>