** Description changed: - Issue found on B-ibm-gt-4.15.0-1116.127 + [Impact] + rdpru test in ubuntu_kvm_unit_tests is to check if the RDPRU instruction can be intercepted by the Hypervisor. + + RDPRU is one of the new instruction set extensions of AMD "Zen 2" CPUs + that is for reading a processor register that is typically limited to + privilege level zero. RDPRU allows for reading select registers at any + privilege level. With Linux 5.5, the RDPRU presence will be advertised + by the CPU features. + + Without this patchset, the rdpru test will fail on our AMD Zen 2 system + "riccioli" + + [Fix] + * 9d40b85b x86/cpufeatures: Add feature bit RDPRU on AMD + * 0cb8410b kvm: svm: Intercept RDPRU + + We have these patches in newer releases already, only Bionic 4.15 + require this fix. And they can be cherry-picked without any conflict. + + [Test] + With the patched kernel, this rdpru test will pass on the target AMD Zen 2 system. + + And the rdpru flag will be available in cpuinfo: + flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl xtopology nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 invpcid_single hw_pstate ssbd ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold v_vmsave_vmload vgif umip pku ospke vaes vpclmulqdq rdpid overflow_recov succor smca + bugs : sysret_ss_attrs spectre_v1 spectre_v2 spec_store_bypass + + $ sudo ./rdpru + BUILD_HEAD=16647354 + timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel /tmp/tmp.syc17ecDpN -smp 1 -cpu max # -initrd /tmp/tmp.poLG53JqrJ + enabling apic + PASS: RDPRU raises #UD + SUMMARY: 1 tests + PASS rdpru (1 tests) + + [Where problems could occur] + This patchset will add a new feature bit RDPRU, the impact should be small as it's still up to user-space for making use of it. + + [Original Bug Report] + Issue found on B-ibm-gt-4.15.0-1116.127 This can be reproduced with B-4.15.0-175 as well. This failure is only visible on this node. Running '/home/ubuntu/autotest/client/tmp/ubuntu_kvm_unit_tests/src/kvm-unit-tests/tests/rdpru' BUILD_HEAD=16647354 timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -machine accel=kvm -kernel /tmp/tmp.qGIR5tvTw1 -smp 1 -cpu max # -initrd /tmp/tmp.8JuYRCFRUi enabling apic FAIL: RDPRU raises #UD SUMMARY: 1 tests, 1 unexpected failures FAIL rdpru (1 tests, 1 unexpected failures)
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1968681 Title: rdpru in ubuntu_kvm_unit_tests failed on B-4.15 node riccioli with FAIL: RDPRU raises #UD To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1968681/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
