kernel/tools/testing/selftests/kvm/rseq_test.c, branch linux-6.2.y

KVM: selftests: move common startup logic to kvm_util.c

2022-11-17T00:58:56Z

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 Reviewed-by: Andrew Jones Reviewed-by: Peter Gonda Signed-off-by: Vishal Annapurve Link: https://lore.kernel.org/r/20221115213845.3348210-2-vannapurve@google.com Signed-off-by: Sean Christopherson

KVM: selftests: Automatically do init_ucall() for non-barebones VMs

2022-11-17T00:58:51Z

Do init_ucall() automatically during VM creation to kill two (three?) birds with one stone. First, initializing ucall immediately after VM creations allows forcing aarch64's MMIO ucall address to immediately follow memslot0. This is still somewhat fragile as tests could clobber the MMIO address with a new memslot, but it's safe-ish since tests have to be conversative when accounting for memslot0. And this can be hardened in the future by creating a read-only memslot for the MMIO page (KVM ARM exits with MMIO if the guest writes to a read-only memslot). Add a TODO to document that selftests can and should use a memslot for the ucall MMIO (doing so requires yet more rework because tests assumes thay can use all memslots except memslot0). Second, initializing ucall for all VMs prepares for making ucall initialization meaningful on all architectures. aarch64 is currently the only arch that needs to do any setup, but that will change in the future by switching to a pool-based implementation (instead of the current stack-based approach). Lastly, defining the ucall MMIO address from common code will simplify switching all architectures (except s390) to a common MMIO-based ucall implementation (if there's ever sufficient motivation to do so). Cc: Oliver Upton Reviewed-by: Andrew Jones Tested-by: Peter Gonda Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20221006003409.649993-4-seanjc@google.com

selftests: kvm: Fix a compile error in selftests/kvm/rseq_test.c

2022-09-22T21:02:20Z

The following warning appears when executing: make -C tools/testing/selftests/kvm rseq_test.c: In function ‘main’: rseq_test.c:237:33: warning: implicit declaration of function ‘gettid’; did you mean ‘getgid’? [-Wimplicit-function-declaration] (void *)(unsigned long)gettid()); ^~~~~~ getgid /usr/bin/ld: /tmp/ccr5mMko.o: in function `main': ../kvm/tools/testing/selftests/kvm/rseq_test.c:237: undefined reference to `gettid' collect2: error: ld returned 1 exit status make: *** [../lib.mk:173: ../kvm/tools/testing/selftests/kvm/rseq_test] Error 1 Use the more compatible syscall(SYS_gettid) instead of gettid() to fix it. More subsequent reuse may cause it to be wrapped in a lib file. Signed-off-by: Jinrong Liang Message-Id: <20220802071240.84626-1-cloudliang@tencent.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Use getcpu() instead of sched_getcpu() in rseq_test

2022-08-10T19:08:29Z

sched_getcpu() is glibc dependent and it can simply return the CPU ID from the registered rseq information, as Florian Weimer pointed. In this case, it's pointless to compare the return value from sched_getcpu() and that fetched from the registered rseq information. Fix the issue by replacing sched_getcpu() with getcpu(), as Florian suggested. The comments are modified accordingly by replacing "sched_getcpu()" with "getcpu()". Reported-by: Yihuang Yu Suggested-by: Florian Weimer Suggested-by: Mathieu Desnoyers Suggested-by: Sean Christopherson Signed-off-by: Gavin Shan Message-Id: <20220810104114.6838-3-gshan@redhat.com> Signed-off-by: Paolo Bonzini

KVM: selftests: Make rseq compatible with glibc-2.35

2022-08-10T19:08:29Z

The rseq information is registered by TLS, starting from glibc-2.35. In this case, the test always fails due to syscall(__NR_rseq). For example, on RHEL9.1 where upstream glibc-2.35 features are enabled on downstream glibc-2.34, the test fails like below. # ./rseq_test ==== Test Assertion Failure ==== rseq_test.c:60: !r pid=112043 tid=112043 errno=22 - Invalid argument 1 0x0000000000401973: main at rseq_test.c:226 2 0x0000ffff84b6c79b: ?? ??:0 3 0x0000ffff84b6c86b: ?? ??:0 4 0x0000000000401b6f: _start at ??:? rseq failed, errno = 22 (Invalid argument) # rpm -aq | grep glibc-2 glibc-2.34-39.el9.aarch64 Fix the issue by using "../rseq/rseq.c" to fetch the rseq information, registred by TLS if it exists. Otherwise, we're going to register our own rseq information as before. Reported-by: Yihuang Yu Suggested-by: Florian Weimer Suggested-by: Mathieu Desnoyers Suggested-by: Paolo Bonzini Signed-off-by: Gavin Shan Message-Id: <20220810104114.6838-2-gshan@redhat.com> Signed-off-by: Paolo Bonzini

Merge remote-tracking branch 'kvm/next' into kvm-next-5.20

2022-08-01T07:21:00Z

KVM/s390, KVM/x86 and common infrastructure changes for 5.20 x86: * Permit guests to ignore single-bit ECC errors * Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache * Intel IPI virtualization * Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS * PEBS virtualization * Simplify PMU emulation by just using PERF_TYPE_RAW events * More accurate event reinjection on SVM (avoid retrying instructions) * Allow getting/setting the state of the speaker port data bit * Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent * "Notify" VM exit (detect microarchitectural hangs) for Intel * Cleanups for MCE MSR emulation s390: * add an interface to provide a hypervisor dump for secure guests * improve selftests to use TAP interface * enable interpretive execution of zPCI instructions (for PCI passthrough) * First part of deferred teardown * CPU Topology * PV attestation * Minor fixes Generic: * new selftests API using struct kvm_vcpu instead of a (vm, id) tuple x86: * Use try_cmpxchg64 instead of cmpxchg64 * Bugfixes * Ignore benign host accesses to PMU MSRs when PMU is disabled * Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior * x86/MMU: Allow NX huge pages to be disabled on a per-vm basis * Port eager page splitting to shadow MMU as well * Enable CMCI capability by default and handle injected UCNA errors * Expose pid of vcpu threads in debugfs * x2AVIC support for AMD * cleanup PIO emulation * Fixes for LLDT/LTR emulation * Don't require refcounted "struct page" to create huge SPTEs x86 cleanups: * Use separate namespaces for guest PTEs and shadow PTEs bitmasks * PIO emulation * Reorganize rmap API, mostly around rmap destruction * Do not workaround very old KVM bugs for L0 that runs with nesting enabled * new selftests API for CPUID

KVM: selftests: Fix target thread to be migrated in rseq_test

2022-07-19T13:03:49Z

In rseq_test, there are two threads, which are vCPU thread and migration worker separately. Unfortunately, the test has the wrong PID passed to sched_setaffinity() in the migration worker. It forces migration on the migration worker because zeroed PID represents the calling thread, which is the migration worker itself. It means the vCPU thread is never enforced to migration and it can migrate at any time, which eventually leads to failure as the following logs show. host# uname -r 5.19.0-rc6-gavin+ host# # cat /proc/cpuinfo | grep processor | tail -n 1 processor : 223 host# pwd /home/gavin/sandbox/linux.main/tools/testing/selftests/kvm host# for i in `seq 1 100`; do \ echo "--------> $i"; ./rseq_test; done --------> 1 --------> 2 --------> 3 --------> 4 --------> 5 --------> 6 ==== Test Assertion Failure ==== rseq_test.c:265: rseq_cpu == cpu pid=3925 tid=3925 errno=4 - Interrupted system call 1 0x0000000000401963: main at rseq_test.c:265 (discriminator 2) 2 0x0000ffffb044affb: ?? ??:0 3 0x0000ffffb044b0c7: ?? ??:0 4 0x0000000000401a6f: _start at ??:? rseq CPU = 4, sched CPU = 27 Fix the issue by passing correct parameter, TID of the vCPU thread, to sched_setaffinity() in the migration worker. Fixes: 61e52f1630f5 ("KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs") Suggested-by: Sean Christopherson Signed-off-by: Gavin Shan Reviewed-by: Oliver Upton Message-Id: <20220719020830.3479482-1-gshan@redhat.com> Reviewed-by: Andrew Jones Signed-off-by: Paolo Bonzini

KVM: selftests: Add TEST_REQUIRE macros to reduce skipping copy+paste

2022-06-11T15:47:29Z

Add TEST_REQUIRE() and __TEST_REQUIRE() to replace the myriad open coded instances of selftests exiting with KSFT_SKIP after printing an informational message. In addition to reducing the amount of boilerplate code in selftests, the UPPERCASE macro names make it easier to visually identify a test's requirements. Convert usage that erroneously uses something other than print_skip() and/or "exits" with '0' or some other non-KSFT_SKIP value. Intentionally drop a kvm_vm_free() in aarch64/debug-exceptions.c as part of the conversion. All memory and file descriptors are freed on process exit, so the explicit free is superfluous. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini

KVM: selftests: Purge vm+vcpu_id == vcpu silliness

2022-06-11T15:47:22Z

Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers and ioctls. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini

KVM: selftests: Convert rseq_test away from VCPU_ID

2022-06-11T15:46:38Z

Convert rseq_test to use vm_create_with_one_vcpu() and pass around a 'struct kvm_vcpu' object instead of using a global VCPU_ID. Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini