kernel/linux.git/tools/testing/selftests/kvm, branch v6.18.21

KVM: selftests: Add -U_FORTIFY_SOURCE to avoid some unpredictable test failures

2026-02-11T12:41:44+00:00

commit e396a74222654486d6ab45dca5d0c54c408b8b91 upstream. Some distributions (such as Ubuntu) configure GCC so that _FORTIFY_SOURCE is automatically enabled at -O1 or above. This results in some fortified version of definitions of standard library functions are included. While linker resolves the symbols, the fortified versions might override the definitions in lib/string_override.c and reference to those PLT entries in GLIBC. This is not a problem for the code in host, but it is a disaster for the guest code. E.g., if build and run x86/nested_emulation_test on Ubuntu 24.04 will encounter a L1 #PF due to memset() reference to __memset_chk@plt. The option -fno-builtin-memset is not helpful here, because those fortified versions are not built-in but some definitions which are included by header, they are for different intentions. In order to eliminate the unpredictable behaviors may vary depending on the linker and platform, add the "-U_FORTIFY_SOURCE" into CFLAGS to prevent from introducing the fortified definitions. Signed-off-by: Zhiquan Li Link: https://patch.msgid.link/20260122053551.548229-1-zhiquan_li@163.com Fixes: 6b6f71484bf4 ("KVM: selftests: Implement memcmp(), memcpy(), and memset() for guest use") Cc: stable@vger.kernel.org [sean: tag for stable] Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

selftests: kvm: try getting XFD and XSAVE state out of sync

2026-01-23T10:21:23+00:00

commit 0383a8edef396cf0a6884b0be81d62bde60737b0 upstream. The host is allowed to set FPU state that includes a disabled xstate component. Check that this does not cause bad effects. Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

selftests: kvm: replace numbered sync points with actions

2026-01-23T10:21:23+00:00

commit a1025dcd377ef92d9a09af03b70ce80be281ee22 upstream. Rework the guest=>host syncs in the AMX test to use named actions instead of arbitrary, incrementing numbers. The "stage" of the test has no real meaning, what matters is what action the test wants the host to perform. The incrementing numbers are somewhat helpful for triaging failures, but fully debugging failures almost always requires a much deeper dive into the test (and KVM). Using named actions not only makes it easier to extend the test without having to shift all sync point numbers, it makes the code easier to read. [Commit message by Sean Christopherson] Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: selftests: Add missing "break" in rseq_test's param parsing

2026-01-02T11:57:22+00:00

commit 1b9439c933b500cb24710bbd81fe56e9b0025b6f upstream. In commit 0297cdc12a87 ("KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latency"), a 'break' is missed before the option 'l' in the argument parsing loop, which leads to an unexpected core dump in atoi_paranoid(). It tries to get the latency from non-existent argument. host$ ./rseq_test -u Random seed: 0x6b8b4567 Segmentation fault (core dumped) Add a 'break' before the option 'l' in the argument parsing loop to avoid the unexpected core dump. Fixes: 0297cdc12a87 ("KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latency") Cc: stable@vger.kernel.org # v6.15+ Signed-off-by: Gavin Shan Link: https://patch.msgid.link/20251124050427.1924591-1-gshan@redhat.com [sean: describe code change in shortlog] Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

KVM: selftests: Forcefully override ARCH from x86_64 to x86

2026-01-02T11:57:20+00:00

commit 17e5a9b77716564540d81f0c1e6082d28cf305c9 upstream. Forcefully override ARCH from x86_64 to x86 to handle the scenario where the user specifies ARCH=x86_64 on the command line. Fixes: 9af04539d474 ("KVM: selftests: Override ARCH for x86_64 instead of using ARCH_DIR") Cc: stable@vger.kernel.org Reported-by: David Matlack Closes: https://lore.kernel.org/all/20250724213130.3374922-1-dmatlack@google.com Link: https://lore.kernel.org/r/20251007223057.368082-1-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman

Merge tag 'kvmarm-fixes-6.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2025-11-09T07:07:55+00:00

KVM/arm654 fixes for 6.18, take #2 * Core fixes - Fix trapping regression when no in-kernel irqchip is present (20251021094358.1963807-1-sascha.bischoff@arm.com) - Check host-provided, untrusted ranges and offsets in pKVM (20251016164541.3771235-1-vdonnefort@google.com) (20251017075710.2605118-1-sebastianene@google.com) - Fix regression restoring the ID_PFR1_EL1 register (20251030122707.2033690-1-maz@kernel.org - Fix vgic ITS locking issues when LPIs are not directly injected (20251107184847.1784820-1-oupton@kernel.org) * Test fixes - Correct target CPU programming in vgic_lpi_stress selftest (20251020145946.48288-1-mdittgen@amazon.de) - Fix exposure of SCTLR2_EL2 and ZCR_EL2 in get-reg-list selftest (20251023-b4-kvm-arm64-get-reg-list-sctlr-el2-v1-1-088f88ff992a@kernel.org) (20251024-kvm-arm64-get-reg-list-zcr-el2-v1-1-0cd0ff75e22f@kernel.org) * Misc - Update Oliver's email address (20251107012830.1708225-1-oupton@kernel.org)

KVM: arm64: selftests: Filter ZCR_EL2 in get-reg-list

2025-10-30T16:13:27+00:00

get-reg-list includes ZCR_EL2 in the list of EL2 registers that it looks for when NV is enabled but does not have any feature gate for this register, meaning that testing any combination of features that includes EL2 but does not include SVE will result in a test failure due to a missing register being reported: | The following lines are missing registers: | | ARM64_SYS_REG(3, 4, 1, 2, 0), Add ZCR_EL2 to feat_id_regs so that the test knows not to expect to see it without SVE being enabled. Fixes: 3a90b6f27964 ("KVM: arm64: selftests: get-reg-list: Add base EL2 registers") Signed-off-by: Mark Brown Link: https://patch.msgid.link/20251024-kvm-arm64-get-reg-list-zcr-el2-v1-1-0cd0ff75e22f@kernel.org Signed-off-by: Marc Zyngier

KVM: arm64: selftests: Add SCTLR2_EL2 to get-reg-list

2025-10-30T16:13:04+00:00

We recently added support for SCTLR2_EL2 to the kernel but did not add it to get-reg-list, resulting in it reporting the missing register when it is available. Add it. Signed-off-by: Mark Brown Link: https://patch.msgid.link/20251023-b4-kvm-arm64-get-reg-list-sctlr-el2-v1-1-088f88ff992a@kernel.org Signed-off-by: Marc Zyngier

KVM: selftests: fix MAPC RDbase target formatting in vgic_lpi_stress

2025-10-30T16:12:30+00:00

Since GITS_TYPER.PTA == 0, the ITS MAPC command demands a CPU ID, rather than a physical redistributor address, for its RDbase command argument. As such, when MAPC-ing guest ITS collections, vgic_lpi_stress iterates over CPU IDs in the range [0, nr_cpus), passing them as the RDbase vcpu_id argument to its_send_mapc_cmd(). However, its_encode_target() in the its_send_mapc_cmd() selftest handler expects RDbase arguments to be formatted with a 16 bit offset, as shown by the 16-bit target_addr right shift its implementation: its_mask_encode(&cmd->raw_cmd[2], target_addr >> 16, 51, 16) At the moment, all CPU IDs passed into its_send_mapc_cmd() have no offset, therefore becoming 0x0 after the bit shift. Thus, when vgic_its_cmd_handle_mapc() receives the ITS command in vgic-its.c, it always interprets the RDbase target CPU as CPU 0. All interrupts sent to collections will be processed by vCPU 0, which defeats the purpose of this multi-vCPU test. Fix by creating procnum_to_rdbase() helper function, which left-shifts the vCPU parameter received by its_send_mapc_cmd 16 bits before passing it to its_encode_target for encoding. Signed-off-by: Maximilian Dittgen Link: https://patch.msgid.link/20251020145946.48288-1-mdittgen@amazon.de Signed-off-by: Marc Zyngier

Merge tag 'kvm-x86-fixes-6.18-rc2' of https://github.com/kvm-x86/linux into HEAD

2025-10-18T08:25:43+00:00

KVM x86 fixes for 6.18: - Expand the KVM_PRE_FAULT_MEMORY selftest to add a regression test for the bug fixed by commit 3ccbf6f47098 ("KVM: x86/mmu: Return -EAGAIN if userspace deletes/moves memslot during prefault") - Don't try to get PMU capabbilities from perf when running a CPU with hybrid CPUs/PMUs, as perf will rightly WARN. - Rework KVM_CAP_GUEST_MEMFD_MMAP (newly introduced in 6.18) into a more generic KVM_CAP_GUEST_MEMFD_FLAGS - Add a guest_memfd INIT_SHARED flag and require userspace to explicitly set said flag to initialize memory as SHARED, irrespective of MMAP. The behavior merged in 6.18 is that enabling mmap() implicitly initializes memory as SHARED, which would result in an ABI collision for x86 CoCo VMs as their memory is currently always initialized PRIVATE. - Allow mmap() on guest_memfd for x86 CoCo VMs, i.e. on VMs with private memory, to enable testing such setups, i.e. to hopefully flush out any other lurking ABI issues before 6.18 is officially released. - Add testcases to the guest_memfd selftest to cover guest_memfd without MMAP, and host userspace accesses to mmap()'d private memory.