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2022-05-25x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave)Sean Christopherson
Set the starting uABI size of KVM's guest FPU to 'struct kvm_xsave', i.e. to KVM's historical uABI size. When saving FPU state for usersapce, KVM (well, now the FPU) sets the FP+SSE bits in the XSAVE header even if the host doesn't support XSAVE. Setting the XSAVE header allows the VM to be migrated to a host that does support XSAVE without the new host having to handle FPU state that may or may not be compatible with XSAVE. Setting the uABI size to the host's default size results in out-of-bounds writes (setting the FP+SSE bits) and data corruption (that is thankfully caught by KASAN) when running on hosts without XSAVE, e.g. on Core2 CPUs. WARN if the default size is larger than KVM's historical uABI size; all features that can push the FPU size beyond the historical size must be opt-in. ================================================================== BUG: KASAN: slab-out-of-bounds in fpu_copy_uabi_to_guest_fpstate+0x86/0x130 Read of size 8 at addr ffff888011e33a00 by task qemu-build/681 CPU: 1 PID: 681 Comm: qemu-build Not tainted 5.18.0-rc5-KASAN-amd64 #1 Hardware name: /DG35EC, BIOS ECG3510M.86A.0118.2010.0113.1426 01/13/2010 Call Trace: <TASK> dump_stack_lvl+0x34/0x45 print_report.cold+0x45/0x575 kasan_report+0x9b/0xd0 fpu_copy_uabi_to_guest_fpstate+0x86/0x130 kvm_arch_vcpu_ioctl+0x72a/0x1c50 [kvm] kvm_vcpu_ioctl+0x47f/0x7b0 [kvm] __x64_sys_ioctl+0x5de/0xc90 do_syscall_64+0x31/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xae </TASK> Allocated by task 0: (stack is not available) The buggy address belongs to the object at ffff888011e33800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes to the right of 512-byte region [ffff888011e33800, ffff888011e33a00) The buggy address belongs to the physical page: page:0000000089cd4adb refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11e30 head:0000000089cd4adb order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888001041c80 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888011e33900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888011e33980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888011e33a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888011e33a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888011e33b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Disabling lock debugging due to kernel taint Fixes: be50b2065dfa ("kvm: x86: Add support for getting/setting expanded xstate buffer") Fixes: c60427dd50ba ("x86/fpu: Add uabi_size to guest_fpu") Reported-by: Zdenek Kaspar <zkaspar82@gmail.com> Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Zdenek Kaspar <zkaspar82@gmail.com> Message-Id: <20220504001219.983513-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-25Merge tag 'kvm-riscv-5.19-1' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini
KVM/riscv changes for 5.19 - Added Sv57x4 support for G-stage page table - Added range based local HFENCE functions - Added remote HFENCE functions based on VCPU requests - Added ISA extension registers in ONE_REG interface - Updated KVM RISC-V maintainers entry to cover selftests support
2022-05-25Merge tag 'kvmarm-5.19' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.19 - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes [Due to the conflict, KVM_SYSTEM_EVENT_SEV_TERM is relocated from 4 to 6. - Paolo]
2022-05-25KVM: LAPIC: Trace LAPIC timer expiration on every vmentryWanpeng Li
In commit ec0671d5684a ("KVM: LAPIC: Delay trace_kvm_wait_lapic_expire tracepoint to after vmexit", 2019-06-04), trace_kvm_wait_lapic_expire was moved after guest_exit_irqoff() because invoking tracepoints within kvm_guest_enter/kvm_guest_exit caused a lockdep splat. These days this is not necessary, because commit 87fa7f3e98a1 ("x86/kvm: Move context tracking where it belongs", 2020-07-09) restricted the RCU extended quiescent state to be closer to vmentry/vmexit. Moving the tracepoint back to __kvm_wait_lapic_expire is more accurate, because it will be reported even if vcpu_enter_guest causes multiple vmentries via the IPI/Timer fast paths, and it allows the removal of advance_expire_delta. Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1650961551-38390-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-24Merge tag 'pm-5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add support for 'artificial' Energy Models in which power numbers for different entities may be in different scales, add support for some new hardware, fix bugs and clean up code in multiple places. Specifics: - Update the Energy Model support code to allow the Energy Model to be artificial, which means that the power values may not be on a uniform scale with other devices providing power information, and update the cpufreq_cooling and devfreq_cooling thermal drivers to support artificial Energy Models (Lukasz Luba). - Make DTPM check the Energy Model type (Lukasz Luba). - Fix policy counter decrementation in cpufreq if Energy Model is in use (Pierre Gondois). - Add CPU-based scaling support to passive devfreq governor (Saravana Kannan, Chanwoo Choi). - Update the rk3399_dmc devfreq driver (Brian Norris). - Export dev_pm_ops instead of suspend() and resume() in the IIO chemical scd30 driver (Jonathan Cameron). - Add namespace variants of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and PM-runtime counterparts (Jonathan Cameron). - Move symbol exports in the IIO chemical scd30 driver into the IIO_SCD30 namespace (Jonathan Cameron). - Avoid device PM-runtime usage count underflows (Rafael Wysocki). - Allow dynamic debug to control printing of PM messages (David Cohen). - Fix some kernel-doc comments in hibernation code (Yang Li, Haowen Bai). - Preserve ACPI-table override during hibernation (Amadeusz Sławiński). - Improve support for suspend-to-RAM for PSCI OSI mode (Ulf Hansson). - Make Intel RAPL power capping driver support the RaptorLake and AlderLake N processors (Zhang Rui, Sumeet Pawnikar). - Remove redundant store to value after multiply in the RAPL power capping driver (Colin Ian King). - Add AlderLake processor support to the intel_idle driver (Zhang Rui). - Fix regression leading to no genpd governor in the PSCI cpuidle driver and fix the riscv-sbi cpuidle driver to allow a genpd governor to be used (Ulf Hansson). - Fix cpufreq governor clean up code to avoid using kfree() directly to free kobject-based items (Kevin Hao). - Prepare cpufreq for powerpc's asm/prom.h cleanup (Christophe Leroy). - Make intel_pstate notify frequency invariance code when no_turbo is turned on and off (Chen Yu). - Add Sapphire Rapids OOB mode support to intel_pstate (Srinivas Pandruvada). - Make cpufreq avoid unnecessary frequency updates due to mismatch between hardware and the frequency table (Viresh Kumar). - Make remove_cpu_dev_symlink() clear the real_cpus mask to simplify code (Viresh Kumar). - Rearrange cpufreq_offline() and cpufreq_remove_dev() to make the calling convention for some driver callbacks consistent (Rafael Wysocki). - Avoid accessing half-initialized cpufreq policies from the show() and store() sysfs functions (Schspa Shi). - Rearrange cpufreq_offline() to make the calling convention for some driver callbacks consistent (Schspa Shi). - Update CPPC handling in cpufreq (Pierre Gondois). - Extend dev_pm_domain_detach() doc (Krzysztof Kozlowski). - Move genpd's time-accounting to ktime_get_mono_fast_ns() (Ulf Hansson). - Improve the way genpd deals with its governors (Ulf Hansson). - Update the turbostat utility to version 2022.04.16 (Len Brown, Dan Merillat, Sumeet Pawnikar, Zephaniah E. Loss-Cutler-Hull, Chen Yu)" * tag 'pm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (94 commits) PM: domains: Trust domain-idle-states from DT to be correct by genpd PM: domains: Measure power-on/off latencies in genpd based on a governor PM: domains: Allocate governor data dynamically based on a genpd governor PM: domains: Clean up some code in pm_genpd_init() and genpd_remove() PM: domains: Fix initialization of genpd's next_wakeup PM: domains: Fixup QoS latency measurements for IRQ safe devices in genpd PM: domains: Measure suspend/resume latencies in genpd based on governor PM: domains: Move the next_wakeup variable into the struct gpd_timing_data PM: domains: Allocate gpd_timing_data dynamically based on governor PM: domains: Skip another warning in irq_safe_dev_in_sleep_domain() PM: domains: Rename irq_safe_dev_in_no_sleep_domain() in genpd PM: domains: Don't check PM_QOS_FLAG_NO_POWER_OFF in genpd PM: domains: Drop redundant code for genpd always-on governor PM: domains: Add GENPD_FLAG_RPM_ALWAYS_ON for the always-on governor powercap: intel_rapl: remove redundant store to value after multiply cpufreq: CPPC: Enable dvfs_possible_from_any_cpu cpufreq: CPPC: Enable fast_switch ACPI: CPPC: Assume no transition latency if no PCCT ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported ACPI: CPPC: Check _OSC for flexible address space ...
2022-05-24Merge tag 'acpi-5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These update the ACPICA kernel code to upstream revision 20220331, improve handling of PCI devices that are in D3cold during system initialization, add support for a few features, fix bugs and clean up code. Specifics: - Update ACPICA code in the kernel to upstream revision 20220331 including the following changes: - Add support for the Windows 11 _OSI string (Mario Limonciello) - Add the CFMWS subtable to the CEDT table (Lawrence Hileman). - iASL: NHLT: Treat Terminator as specific_config (Piotr Maziarz). - iASL: NHLT: Fix parsing undocumented bytes at the end of Endpoint Descriptor (Piotr Maziarz). - iASL: NHLT: Rename linux specific strucures to device_info (Piotr Maziarz). - Add new ACPI 6.4 semantics to Load() and LoadTable() (Bob Moore). - Clean up double word in comment (Tom Rix). - Update copyright notices to the year 2022 (Bob Moore). - Remove some tabs and // comments - automated cleanup (Bob Moore). - Replace zero-length array with flexible-array member (Gustavo A. R. Silva). - Interpreter: Add units to time variable names (Paul Menzel). - Add support for ARM Performance Monitoring Unit Table (Besar Wicaksono). - Inform users about ACPI spec violation related to sleep length (Paul Menzel). - iASL/MADT: Add OEM-defined subtable (Bob Moore). - Interpreter: Fix some typo mistakes (Selvarasu Ganesan). - Updates for revision E.d of IORT (Shameer Kolothum). - Use ACPI_FORMAT_UINT64 for 64-bit output (Bob Moore). - Improve debug messages in the ACPI device PM code (Rafael Wysocki). - Block ASUS B1400CEAE from suspend to idle by default (Mario Limonciello). - Improve handling of PCI devices that are in D3cold during system initialization (Rafael Wysocki). - Fix BERT error region memory mapping (Lorenzo Pieralisi). - Add support for NVIDIA 16550-compatible port subtype to the SPCR parsing code (Jeff Brasen). - Use static for BGRT_SHOW kobj_attribute defines (Tom Rix). - Fix missing prototype warning for acpi_agdi_init() (Ilkka Koskinen). - Fix missing ERST record ID in the APEI code (Liu Xinpeng). - Make APEI error injection to refuse to inject into the zero page (Tony Luck). - Correct description of INT3407 / INT3532 DPTF attributes in sysfs (Sumeet Pawnikar). - Add support for high frequency impedance notification to the DPTF driver (Sumeet Pawnikar). - Make mp_config_acpi_gsi() a void function (Li kunyu). - Unify Package () representation for properties in the ACPI device properties documentation (Andy Shevchenko). - Include UUID in _DSM evaluation warning (Michael Niewöhner)" * tag 'acpi-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (41 commits) Revert "ACPICA: executer/exsystem: Warn about sleeps greater than 10 ms" ACPI: utils: include UUID in _DSM evaluation warning ACPI: PM: Block ASUS B1400CEAE from suspend to idle by default x86: ACPI: Make mp_config_acpi_gsi() a void function ACPI: DPTF: Add support for high frequency impedance notification ACPI: AGDI: Fix missing prototype warning for acpi_agdi_init() ACPI: bus: Avoid non-ACPI device objects in walks over children ACPI: DPTF: Correct description of INT3407 / INT3532 attributes ACPI: BGRT: use static for BGRT_SHOW kobj_attribute defines ACPI, APEI, EINJ: Refuse to inject into the zero page ACPI: PM: Always print final debug message in acpi_device_set_power() ACPI: SPCR: Add support for NVIDIA 16550-compatible port subtype ACPI: docs: enumeration: Unify Package () for properties (part 2) ACPI: APEI: Fix missing ERST record id ACPICA: Update version to 20220331 ACPICA: exsystem.c: Use ACPI_FORMAT_UINT64 for 64-bit output ACPICA: IORT: Updates for revision E.d ACPICA: executer/exsystem: Fix some typo mistakes ACPICA: iASL/MADT: Add OEM-defined subtable ACPICA: executer/exsystem: Warn about sleeps greater than 10 ms ...
2022-05-24Merge tag 'kernel-hardening-v5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull kernel hardening updates from Kees Cook: - usercopy hardening expanded to check other allocation types (Matthew Wilcox, Yuanzheng Song) - arm64 stackleak behavioral improvements (Mark Rutland) - arm64 CFI code gen improvement (Sami Tolvanen) - LoadPin LSM block dev API adjustment (Christoph Hellwig) - Clang randstruct support (Bill Wendling, Kees Cook) * tag 'kernel-hardening-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (34 commits) loadpin: stop using bdevname mm: usercopy: move the virt_addr_valid() below the is_vmalloc_addr() gcc-plugins: randstruct: Remove cast exception handling af_unix: Silence randstruct GCC plugin warning niu: Silence randstruct warnings big_keys: Use struct for internal payload gcc-plugins: Change all version strings match kernel randomize_kstack: Improve docs on requirements/rationale lkdtm/stackleak: fix CONFIG_GCC_PLUGIN_STACKLEAK=n arm64: entry: use stackleak_erase_on_task_stack() stackleak: add on/off stack variants lkdtm/stackleak: check stack boundaries lkdtm/stackleak: prevent unexpected stack usage lkdtm/stackleak: rework boundary management lkdtm/stackleak: avoid spurious failure stackleak: rework poison scanning stackleak: rework stack high bound handling stackleak: clarify variable names stackleak: rework stack low bound handling stackleak: remove redundant check ...
2022-05-24Merge tag 'random-5.19-rc1-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: "These updates continue to refine the work began in 5.17 and 5.18 of modernizing the RNG's crypto and streamlining and documenting its code. New for 5.19, the updates aim to improve entropy collection methods and make some initial decisions regarding the "premature next" problem and our threat model. The cloc utility now reports that random.c is 931 lines of code and 466 lines of comments, not that basic metrics like that mean all that much, but at the very least it tells you that this is very much a manageable driver now. Here's a summary of the various updates: - The random_get_entropy() function now always returns something at least minimally useful. This is the primary entropy source in most collectors, which in the best case expands to something like RDTSC, but prior to this change, in the worst case it would just return 0, contributing nothing. For 5.19, additional architectures are wired up, and architectures that are entirely missing a cycle counter now have a generic fallback path, which uses the highest resolution clock available from the timekeeping subsystem. Some of those clocks can actually be quite good, despite the CPU not having a cycle counter of its own, and going off-core for a stamp is generally thought to increase jitter, something positive from the perspective of entropy gathering. Done very early on in the development cycle, this has been sitting in next getting some testing for a while now and has relevant acks from the archs, so it should be pretty well tested and fine, but is nonetheless the thing I'll be keeping my eye on most closely. - Of particular note with the random_get_entropy() improvements is MIPS, which, on CPUs that lack the c0 count register, will now combine the high-speed but short-cycle c0 random register with the lower-speed but long-cycle generic fallback path. - With random_get_entropy() now always returning something useful, the interrupt handler now collects entropy in a consistent construction. - Rather than comparing two samples of random_get_entropy() for the jitter dance, the algorithm now tests many samples, and uses the amount of differing ones to determine whether or not jitter entropy is usable and how laborious it must be. The problem with comparing only two samples was that if the cycle counter was extremely slow, but just so happened to be on the cusp of a change, the slowness wouldn't be detected. Taking many samples fixes that to some degree. This, combined with the other improvements to random_get_entropy(), should make future unification of /dev/random and /dev/urandom maybe more possible. At the very least, were we to attempt it again today (we're not), it wouldn't break any of Guenter's test rigs that broke when we tried it with 5.18. So, not today, but perhaps down the road, that's something we can revisit. - We attempt to reseed the RNG immediately upon waking up from system suspend or hibernation, making use of the various timestamps about suspend time and such available, as well as the usual inputs such as RDRAND when available. - Batched randomness now falls back to ordinary randomness before the RNG is initialized. This provides more consistent guarantees to the types of random numbers being returned by the various accessors. - The "pre-init injection" code is now gone for good. I suspect you in particular will be happy to read that, as I recall you expressing your distaste for it a few months ago. Instead, to avoid a "premature first" issue, while still allowing for maximal amount of entropy availability during system boot, the first 128 bits of estimated entropy are used immediately as it arrives, with the next 128 bits being buffered. And, as before, after the RNG has been fully initialized, it winds up reseeding anyway a few seconds later in most cases. This resulted in a pretty big simplification of the initialization code and let us remove various ad-hoc mechanisms like the ugly crng_pre_init_inject(). - The RNG no longer pretends to handle the "premature next" security model, something that various academics and other RNG designs have tried to care about in the past. After an interesting mailing list thread, these issues are thought to be a) mainly academic and not practical at all, and b) actively harming the real security of the RNG by delaying new entropy additions after a potential compromise, making a potentially bad situation even worse. As well, in the first place, our RNG never even properly handled the premature next issue, so removing an incomplete solution to a fake problem was particularly nice. This allowed for numerous other simplifications in the code, which is a lot cleaner as a consequence. If you didn't see it before, https://lore.kernel.org/lkml/YmlMGx6+uigkGiZ0@zx2c4.com/ may be a thread worth skimming through. - While the interrupt handler received a separate code path years ago that avoids locks by using per-cpu data structures and a faster mixing algorithm, in order to reduce interrupt latency, input and disk events that are triggered in hardirq handlers were still hitting locks and more expensive algorithms. Those are now redirected to use the faster per-cpu data structures. - Rather than having the fake-crypto almost-siphash-based random32 implementation be used right and left, and in many places where cryptographically secure randomness is desirable, the batched entropy code is now fast enough to replace that. - As usual, numerous code quality and documentation cleanups. For example, the initialization state machine now uses enum symbolic constants instead of just hard coding numbers everywhere. - Since the RNG initializes once, and then is always initialized thereafter, a pretty heavy amount of code used during that initialization is never used again. It is now completely cordoned off using static branches and it winds up in the .text.unlikely section so that it doesn't reduce cache compactness after the RNG is ready. - A variety of functions meant for waiting on the RNG to be initialized were only used by vsprintf, and in not a particularly optimal way. Replacing that usage with a more ordinary setup made it possible to remove those functions. - A cleanup of how we warn userspace about the use of uninitialized /dev/urandom and uninitialized get_random_bytes() usage. Interestingly, with the change you merged for 5.18 that attempts to use jitter (but does not block if it can't), the majority of users should never see those warnings for /dev/urandom at all now, and the one for in-kernel usage is mainly a debug thing. - The file_operations struct for /dev/[u]random now implements .read_iter and .write_iter instead of .read and .write, allowing it to also implement .splice_read and .splice_write, which makes splice(2) work again after it was broken here (and in many other places in the tree) during the set_fs() removal. This was a bit of a last minute arrival from Jens that hasn't had as much time to bake, so I'll be keeping my eye on this as well, but it seems fairly ordinary. Unfortunately, read_iter() is around 3% slower than read() in my tests, which I'm not thrilled about. But Jens and Al, spurred by this observation, seem to be making progress in removing the bottlenecks on the iter paths in the VFS layer in general, which should remove the performance gap for all drivers. - Assorted other bug fixes, cleanups, and optimizations. - A small SipHash cleanup" * tag 'random-5.19-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (49 commits) random: check for signals after page of pool writes random: wire up fops->splice_{read,write}_iter() random: convert to using fops->write_iter() random: convert to using fops->read_iter() random: unify batched entropy implementations random: move randomize_page() into mm where it belongs random: remove mostly unused async readiness notifier random: remove get_random_bytes_arch() and add rng_has_arch_random() random: move initialization functions out of hot pages random: make consistent use of buf and len random: use proper return types on get_random_{int,long}_wait() random: remove extern from functions in header random: use static branch for crng_ready() random: credit architectural init the exact amount random: handle latent entropy and command line from random_init() random: use proper jiffies comparison macro random: remove ratelimiting for in-kernel unseeded randomness random: move initialization out of reseeding hot path random: avoid initializing twice in credit race random: use symbolic constants for crng_init states ...
2022-05-24Merge tag 'perf-core-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events updates from Ingo Molnar: "Platform PMU changes: - x86/intel: - Add new Intel Alder Lake and Raptor Lake support - x86/amd: - AMD Zen4 IBS extensions support - Add AMD PerfMonV2 support - Add AMD Fam19h Branch Sampling support Generic changes: - signal: Deliver SIGTRAP on perf event asynchronously if blocked Perf instrumentation can be driven via SIGTRAP, but this causes a problem when SIGTRAP is blocked by a task & terminate the task. Allow user-space to request these signals asynchronously (after they get unblocked) & also give the information to the signal handler when this happens: "To give user space the ability to clearly distinguish synchronous from asynchronous signals, introduce siginfo_t::si_perf_flags and TRAP_PERF_FLAG_ASYNC (opted for flags in case more binary information is required in future). The resolution to the problem is then to (a) no longer force the signal (avoiding the terminations), but (b) tell user space via si_perf_flags if the signal was synchronous or not, so that such signals can be handled differently (e.g. let user space decide to ignore or consider the data imprecise). " - Unify/standardize the /sys/devices/cpu/events/* output format. - Misc fixes & cleanups" * tag 'perf-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) perf/x86/amd/core: Fix reloading events for SVM perf/x86/amd: Run AMD BRS code only on supported hw perf/x86/amd: Fix AMD BRS period adjustment perf/x86/amd: Remove unused variable 'hwc' perf/ibs: Fix comment perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute perf/amd/ibs: Add support for L3 miss filtering perf/amd/ibs: Use ->is_visible callback for dynamic attributes perf/amd/ibs: Cascade pmu init functions' return value perf/x86/uncore: Add new Alder Lake and Raptor Lake support perf/x86/uncore: Clean up uncore_pci_ids[] perf/x86/cstate: Add new Alder Lake and Raptor Lake support perf/x86/msr: Add new Alder Lake and Raptor Lake support perf/x86: Add new Alder Lake and Raptor Lake support perf/amd/ibs: Use interrupt regs ip for stack unwinding perf/x86/amd/core: Add PerfMonV2 overflow handling perf/x86/amd/core: Add PerfMonV2 counter control perf/x86/amd/core: Detect available counters perf/x86/amd/core: Detect PerfMonV2 support x86/msr: Add PerfCntrGlobal* registers ...
2022-05-24Merge tag 'objtool-core-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool updates from Ingo Molnar: - Comprehensive interface overhaul: ================================= Objtool's interface has some issues: - Several features are done unconditionally, without any way to turn them off. Some of them might be surprising. This makes objtool tricky to use, and prevents porting individual features to other arches. - The config dependencies are too coarse-grained. Objtool enablement is tied to CONFIG_STACK_VALIDATION, but it has several other features independent of that. - The objtool subcmds ("check" and "orc") are clumsy: "check" is really a subset of "orc", so it has all the same options. The subcmd model has never really worked for objtool, as it only has a single purpose: "do some combination of things on an object file". - The '--lto' and '--vmlinux' options are nonsensical and have surprising behavior. Overhaul the interface: - get rid of subcmds - make all features individually selectable - remove and/or clarify confusing/obsolete options - update the documentation - fix some bugs found along the way - Fix x32 regression - Fix Kbuild cleanup bugs - Add scripts/objdump-func helper script to disassemble a single function from an object file. - Rewrite scripts/faddr2line to be section-aware, by basing it on 'readelf', moving it away from 'nm', which doesn't handle multiple sections well, which can result in decoding failure. - Rewrite & fix symbol handling - which had a number of bugs wrt. object files that don't have global symbols - which is rare but possible. Also fix a bunch of symbol handling bugs found along the way. * tag 'objtool-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) objtool: Fix objtool regression on x32 systems objtool: Fix symbol creation scripts/faddr2line: Fix overlapping text section failures scripts: Create objdump-func helper script objtool: Remove libsubcmd.a when make clean objtool: Remove inat-tables.c when make clean objtool: Update documentation objtool: Remove --lto and --vmlinux in favor of --link objtool: Add HAVE_NOINSTR_VALIDATION objtool: Rename "VMLINUX_VALIDATION" -> "NOINSTR_VALIDATION" objtool: Make noinstr hacks optional objtool: Make jump label hack optional objtool: Make static call annotation optional objtool: Make stack validation frame-pointer-specific objtool: Add CONFIG_OBJTOOL objtool: Extricate sls from stack validation objtool: Rework ibt and extricate from stack validation objtool: Make stack validation optional objtool: Add option to print section addresses objtool: Don't print parentheses in function addresses ...
2022-05-24Merge tag 'locking-core-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: - rwsem cleanups & optimizations/fixes: - Conditionally wake waiters in reader/writer slowpaths - Always try to wake waiters in out_nolock path - Add try_cmpxchg64() implementation, with arch optimizations - and use it to micro-optimize sched_clock_{local,remote}() - Various force-inlining fixes to address objdump instrumentation-check warnings - Add lock contention tracepoints: lock:contention_begin lock:contention_end - Misc smaller fixes & cleanups * tag 'locking-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/clock: Use try_cmpxchg64 in sched_clock_{local,remote} locking/atomic/x86: Introduce arch_try_cmpxchg64 locking/atomic: Add generic try_cmpxchg64 support futex: Remove a PREEMPT_RT_FULL reference. locking/qrwlock: Change "queue rwlock" to "queued rwlock" lockdep: Delete local_irq_enable_in_hardirq() locking/mutex: Make contention tracepoints more consistent wrt adaptive spinning locking: Apply contention tracepoints in the slow path locking: Add lock contention tracepoints locking/rwsem: Always try to wake waiters in out_nolock path locking/rwsem: Conditionally wake waiters in reader/writer slowpaths locking/rwsem: No need to check for handoff bit if wait queue empty lockdep: Fix -Wunused-parameter for _THIS_IP_ x86/mm: Force-inline __phys_addr_nodebug() x86/kvm/svm: Force-inline GHCB accessors task_stack, x86/cea: Force-inline stack helpers
2022-05-24livepatch: Remove klp_arch_set_pc() and asm/livepatch.hChristophe Leroy
All three versions of klp_arch_set_pc() do exactly the same: they call ftrace_instruction_pointer_set(). Call ftrace_instruction_pointer_set() directly and remove klp_arch_set_pc(). As klp_arch_set_pc() was the only thing remaining in asm/livepatch.h on x86 and s390, remove asm/livepatch.h livepatch.h remains on powerpc but its content is exclusively used by powerpc specific code. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Petr Mladek <pmladek@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Petr Mladek <pmladek@suse.com>
2022-05-23Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Initial support for the ARMv9 Scalable Matrix Extension (SME). SME takes the approach used for vectors in SVE and extends this to provide architectural support for matrix operations. No KVM support yet, SME is disabled in guests. - Support for crashkernel reservations above ZONE_DMA via the 'crashkernel=X,high' command line option. - btrfs search_ioctl() fix for live-lock with sub-page faults. - arm64 perf updates: support for the Hisilicon "CPA" PMU for monitoring coherent I/O traffic, support for Arm's CMN-650 and CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup. - Kselftest updates for SME, BTI, MTE. - Automatic generation of the system register macros from a 'sysreg' file describing the register bitfields. - Update the type of the function argument holding the ESR_ELx register value to unsigned long to match the architecture register size (originally 32-bit but extended since ARMv8.0). - stacktrace cleanups. - ftrace cleanups. - Miscellaneous updates, most notably: arm64-specific huge_ptep_get(), avoid executable mappings in kexec/hibernate code, drop TLB flushing from get_clear_flush() (and rename it to get_clear_contig()), ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits) arm64/sysreg: Generate definitions for FAR_ELx arm64/sysreg: Generate definitions for DACR32_EL2 arm64/sysreg: Generate definitions for CSSELR_EL1 arm64/sysreg: Generate definitions for CPACR_ELx arm64/sysreg: Generate definitions for CONTEXTIDR_ELx arm64/sysreg: Generate definitions for CLIDR_EL1 arm64/sve: Move sve_free() into SVE code section arm64: Kconfig.platforms: Add comments arm64: Kconfig: Fix indentation and add comments arm64: mm: avoid writable executable mappings in kexec/hibernate code arm64: lds: move special code sections out of kernel exec segment arm64/hugetlb: Implement arm64 specific huge_ptep_get() arm64/hugetlb: Use ptep_get() to get the pte value of a huge page arm64: kdump: Do not allocate crash low memory if not needed arm64/sve: Generate ZCR definitions arm64/sme: Generate defintions for SVCR arm64/sme: Generate SMPRI_EL1 definitions arm64/sme: Automatically generate SMPRIMAP_EL2 definitions arm64/sme: Automatically generate SMIDR_EL1 defines arm64/sme: Automatically generate defines for SMCR ...
2022-05-23Merge tag 's390-5.19-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: - Make use of the IBM z16 processor activity instrumentation facility to count cryptography operations: add a new PMU device driver so that perf can make use of this. - Add new IBM z16 extended counter set to cpumf support. - Add vdso randomization support. - Add missing KCSAN instrumentation to barriers and spinlocks, which should make s390's KCSAN support complete. - Add support for IPL-complete-control facility: notify the hypervisor that kexec finished work and the kernel starts. - Improve error logging for PCI. - Various small changes to workaround llvm's integrated assembler limitations, and one bug, to make it finally possible to compile the kernel with llvm's integrated assembler. This also requires to raise the minimum clang version to 14.0.0. - Various other small enhancements, bug fixes, and cleanups all over the place. * tag 's390-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits) s390/head: get rid of 31 bit leftovers scripts/min-tool-version.sh: raise minimum clang version to 14.0.0 for s390 s390/boot: do not emit debug info for assembly with llvm's IAS s390/boot: workaround llvm IAS bug s390/purgatory: workaround llvm's IAS limitations s390/entry: workaround llvm's IAS limitations s390/alternatives: remove padding generation code s390/alternatives: provide identical sized orginal/alternative sequences s390/cpumf: add new extended counter set for IBM z16 s390/preempt: disable __preempt_count_add() optimization for PROFILE_ALL_BRANCHES s390/stp: clock_delta should be signed s390/stp: fix todoff size s390/pai: add support for cryptography counters entry: Rename arch_check_user_regs() to arch_enter_from_user_mode() s390/compat: cleanup compat_linux.h header file s390/entry: remove broken and not needed code s390/boot: convert parmarea to C s390/boot: convert initial lowcore to C s390/ptrace: move short psw definitions to ptrace header file s390/head: initialize all new psws ...
2022-05-23Merge tag 'for-linus-5.19-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - decouple the PV interface from kernel internals in the Xen scsifront/scsiback pv drivers - harden the Xen scsifront PV driver against a malicious backend driver - simplify Xen PV frontend driver ring page setup - support Xen setups with multiple domains created at boot time to tolerate Xenstore coming up late - two small cleanup patches * tag 'for-linus-5.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits) xen: add support for initializing xenstore later as HVM domain xen: sync xs_wire.h header with upstream xen x86: xen: remove STACK_FRAME_NON_STANDARD from xen_cpuid xen-blk{back,front}: Update contact points for buffer_squeeze_duration_ms and feature_persistent xen/xenbus: eliminate xenbus_grant_ring() xen/sndfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/usbfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/scsifront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/pcifront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/drmfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/tpmfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/netfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/blkfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/xenbus: add xenbus_setup_ring() service function xen: update ring.h xen/shbuf: switch xen-front-pgdir-shbuf to use INVALID_GRANT_REF xen/dmabuf: switch gntdev-dmabuf to use INVALID_GRANT_REF xen/sound: switch xen_snd_front to use INVALID_GRANT_REF xen/drm: switch xen_drm_front to use INVALID_GRANT_REF xen/usb: switch xen-hcd to use INVALID_GRANT_REF ...
2022-05-23Merge tag 'platform-drivers-x86-v5.19-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform driver updates from Hans de Goede: "This includes some small changes to kernel/stop_machine.c and arch/x86 which are deps of the new Intel IFS support. Highlights: - New drivers: - Intel "In Field Scan" (IFS) support - Winmate FM07/FM07P buttons - Mellanox SN2201 support - AMD PMC driver enhancements - Lots of various other small fixes and hardware-id additions" * tag 'platform-drivers-x86-v5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (54 commits) platform/x86/intel/ifs: Add CPU_SUP_INTEL dependency platform/x86: intel_cht_int33fe: Set driver data platform/x86: intel-hid: fix _DSM function index handling platform/x86: toshiba_acpi: use kobj_to_dev() platform/x86: samsung-laptop: use kobj_to_dev() platform/x86: gigabyte-wmi: Add support for Z490 AORUS ELITE AC and X570 AORUS ELITE WIFI tools/power/x86/intel-speed-select: Fix warning for perf_cap.cpu tools/power/x86/intel-speed-select: Display error on turbo mode disabled Documentation: In-Field Scan platform/x86/intel/ifs: add ABI documentation for IFS trace: platform/x86/intel/ifs: Add trace point to track Intel IFS operations platform/x86/intel/ifs: Add IFS sysfs interface platform/x86/intel/ifs: Add scan test support platform/x86/intel/ifs: Authenticate and copy to secured memory platform/x86/intel/ifs: Check IFS Image sanity platform/x86/intel/ifs: Read IFS firmware image platform/x86/intel/ifs: Add stub driver for In-Field Scan stop_machine: Add stop_core_cpuslocked() for per-core operations x86/msr-index: Define INTEGRITY_CAPABILITIES MSR x86/microcode/intel: Expose collect_cpu_info_early() for IFS ...
2022-05-23Merge tag 'x86_sgx_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SGX updates from Dave Hansen: "A set of patches to prevent crashes in SGX enclaves under heavy memory pressure: SGX uses normal RAM allocated from special shmem files as backing storage when it runs out of SGX memory (EPC). The code was overly aggressive when freeing shmem pages and was inadvertently freeing perfectly good data. This resulted in failures in the SGX instructions used to swap data back into SGX memory. This turned out to be really hard to trigger in mainline. It was originally encountered testing the out-of-tree "SGX2" patches, but later reproduced on mainline. Fix the data loss by being more careful about truncating pages out of the backing storage and more judiciously setting pages dirty" * tag 'x86_sgx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sgx: Ensure no data in PCMD page after truncate x86/sgx: Fix race between reclaimer and page fault handler x86/sgx: Obtain backing storage page with enclave mutex held x86/sgx: Mark PCMD page as dirty when modifying contents x86/sgx: Disconnect backing page references from dirty status
2022-05-23Merge tag 'x86_vdso_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso update from Borislav Petkov: - Get rid of CONFIG_LEGACY_VSYSCALL_EMULATE as nothing should be using it anymore * tag 'x86_vdso_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vsyscall: Remove CONFIG_LEGACY_VSYSCALL_EMULATE
2022-05-23Merge tag 'x86_microcode_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loader update from Borislav Petkov: - Make CPU vendor dependency explicit against random config build failures * tag 'x86_microcode_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Add explicit CPU vendor dependency
2022-05-23Merge tag 'x86_misc_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Borislav Petkov: "A variety of fixes which don't fit any other tip bucket: - Remove unnecessary function export - Correct asm constraint - Fix __setup handlers retval" * tag 'x86_misc_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Cleanup the control_va_addr_alignment() __setup handler x86: Fix return value of __setup handlers x86/delay: Fix the wrong asm constraint in delay_loop() x86/amd_nb: Unexport amd_cache_northbridges()
2022-05-23Merge tag 'x86_splitlock_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 splitlock updates from Borislav Petkov: - Add Raptor Lake to the set of CPU models which support splitlock - Make life miserable for apps using split locks by slowing them down considerably while the rest of the system remains responsive. The hope is it will hurt more and people will really fix their misaligned locks apps. As a result, free a TIF bit. * tag 'x86_splitlock_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Enable the split lock feature on Raptor Lake x86/split-lock: Remove unused TIF_SLD bit x86/split_lock: Make life miserable for split lockers
2022-05-23Merge tag 'x86_apic_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Borislav Petkov: - Always do default APIC routing setup so that cpumasks are properly allocated and are present when later accessed ("nosmp" and x2APIC) - Clarify the bit overlap between an old APIC and a modern, integrated one * tag 'x86_apic_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Do apic driver probe for "nosmp" use case x86/apic: Clarify i82489DX bit overlap in APIC_LVT0
2022-05-23Merge tag 'x86_kdump_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kdump fixlet from Borislav Petkov: - A single debug message fix * tag 'x86_kdump_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/crash: Fix minor typo/bug in debug message
2022-05-23Merge tag 'x86_platform_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Borislav Petkov: - A couple of changes enabling SGI UV5 support * tag 'x86_platform_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/uv: Log gap hole end size x86/platform/uv: Update TSC sync state for UV5 x86/platform/uv: Update NMI Handler for UV5
2022-05-23Merge tag 'x86_mm_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm fixlet from Borislav Petkov: - A sparse address space annotation fix * tag 'x86_mm_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fault: Cast an argument to the proper address space in prefetch()
2022-05-23Merge tag 'x86_fpu_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fpu updates from Borislav Petkov: - Add support for XSAVEC - the Compacted XSTATE saving variant - and thus allow for guests to use this compacted XSTATE variant when the hypervisor exports that support - A variable shadowing cleanup * tag 'x86_fpu_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu: Cleanup variable shadowing x86/fpu/xsave: Support XSAVEC in the kernel
2022-05-23Merge tag 'x86_core_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Borislav Petkov: - Remove all the code around GS switching on 32-bit now that it is not needed anymore - Other misc improvements * tag 'x86_core_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: bug: Use normal relative pointers in 'struct bug_entry' x86/nmi: Make register_nmi_handler() more robust x86/asm: Merge load_gs_index() x86/32: Remove lazy GS macros ELF: Remove elf_core_copy_kernel_regs() x86/32: Simplify ELF_CORE_COPY_REGS
2022-05-23Merge tag 'x86_cleanups_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: - Serious sanitization and cleanup of the whole APERF/MPERF and frequency invariance code along with removing the need for unnecessary IPIs - Finally remove a.out support - The usual trivial cleanups and fixes all over x86 * tag 'x86_cleanups_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86: Remove empty files x86/speculation: Add missing srbds=off to the mitigations= help text x86/prctl: Remove pointless task argument x86/aperfperf: Make it correct on 32bit and UP kernels x86/aperfmperf: Integrate the fallback code from show_cpuinfo() x86/aperfmperf: Replace arch_freq_get_on_cpu() x86/aperfmperf: Replace aperfmperf_get_khz() x86/aperfmperf: Store aperf/mperf data for cpu frequency reads x86/aperfmperf: Make parts of the frequency invariance code unconditional x86/aperfmperf: Restructure arch_scale_freq_tick() x86/aperfmperf: Put frequency invariance aperf/mperf data into a struct x86/aperfmperf: Untangle Intel and AMD frequency invariance init x86/aperfmperf: Separate AP/BP frequency invariance init x86/smp: Move APERF/MPERF code where it belongs x86/aperfmperf: Dont wake idle CPUs in arch_freq_get_on_cpu() x86/process: Fix kernel-doc warning due to a changed function name x86: Remove a.out support x86/mm: Replace nodes_weight() with nodes_empty() where appropriate x86: Replace cpumask_weight() with cpumask_empty() where appropriate x86/pkeys: Remove __arch_set_user_pkey_access() declaration ...
2022-05-23Merge tag 'x86_build_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 build updates from Borislav Petkov: - Add a "make x86_debug.config" target which enables a bunch of useful config debug options when trying to debug an issue - A gcc-12 build warnings fix * tag 'x86_build_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Wrap literal addresses in absolute_pointer() x86/configs: Add x86 debugging Kconfig fragment plus docs
2022-05-23Merge tag 'x86_asm_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Borislav Petkov: - A bunch of changes towards streamlining low level asm helpers' calling conventions so that former can be converted to C eventually - Simplify PUSH_AND_CLEAR_REGS so that it can be used at the system call entry paths instead of having opencoded, slightly different variants of it everywhere - Misc other fixes * tag 'x86_asm_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry: Fix register corruption in compat syscall objtool: Fix STACK_FRAME_NON_STANDARD reloc type linkage: Fix issue with missing symbol size x86/entry: Remove skip_r11rcx x86/entry: Use PUSH_AND_CLEAR_REGS for compat x86/entry: Simplify entry_INT80_compat() x86/mm: Simplify RESERVE_BRK() x86/entry: Convert SWAPGS to swapgs and remove the definition of SWAPGS x86/entry: Don't call error_entry() for XENPV x86/entry: Move CLD to the start of the idtentry macro x86/entry: Move PUSH_AND_CLEAR_REGS out of error_entry() x86/entry: Switch the stack after error_entry() returns x86/traps: Use pt_regs directly in fixup_bad_iret()
2022-05-23Merge tag 'x86_cpu_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU feature updates from Borislav Petkov: - Remove a bunch of chicken bit options to turn off CPU features which are not really needed anymore - Misc fixes and cleanups * tag 'x86_cpu_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation: Add missing prototype for unpriv_ebpf_notify() x86/pm: Fix false positive kmemleak report in msr_build_context() x86/speculation/srbds: Do not try to turn mitigation off when not supported x86/cpu: Remove "noclflush" x86/cpu: Remove "noexec" x86/cpu: Remove "nosmep" x86/cpu: Remove CONFIG_X86_SMAP and "nosmap" x86/cpu: Remove "nosep" x86/cpu: Allow feature bit names from /proc/cpuinfo in clearcpuid=
2022-05-23Merge tag 'x86_tdx_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull Intel TDX support from Borislav Petkov: "Intel Trust Domain Extensions (TDX) support. This is the Intel version of a confidential computing solution called Trust Domain Extensions (TDX). This series adds support to run the kernel as part of a TDX guest. It provides similar guest protections to AMD's SEV-SNP like guest memory and register state encryption, memory integrity protection and a lot more. Design-wise, it differs from AMD's solution considerably: it uses a software module which runs in a special CPU mode called (Secure Arbitration Mode) SEAM. As the name suggests, this module serves as sort of an arbiter which the confidential guest calls for services it needs during its lifetime. Just like AMD's SNP set, this series reworks and streamlines certain parts of x86 arch code so that this feature can be properly accomodated" * tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) x86/tdx: Fix RETs in TDX asm x86/tdx: Annotate a noreturn function x86/mm: Fix spacing within memory encryption features message x86/kaslr: Fix build warning in KASLR code in boot stub Documentation/x86: Document TDX kernel architecture ACPICA: Avoid cache flush inside virtual machines x86/tdx/ioapic: Add shared bit for IOAPIC base address x86/mm: Make DMA memory shared for TD guest x86/mm/cpa: Add support for TDX shared memory x86/tdx: Make pages shared in ioremap() x86/topology: Disable CPU online/offline control for TDX guests x86/boot: Avoid #VE during boot for TDX platforms x86/boot: Set CR0.NE early and keep it set during the boot x86/acpi/x86/boot: Add multiprocessor wake-up support x86/boot: Add a trampoline for booting APs via firmware handoff x86/tdx: Wire up KVM hypercalls x86/tdx: Port I/O: Add early boot support x86/tdx: Port I/O: Add runtime hypercalls x86/boot: Port I/O: Add decompression-time support for TDX x86/boot: Port I/O: Allow to hook up alternative helpers ...
2022-05-23Merge tag 'ras_core_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Borislav Petkov: - Simplification of the AMD MCE error severity grading logic along with supplying critical panic MCEs with accompanying error messages for more human-friendly diagnostics. - Misc fixes * tag 'ras_core_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Add messages for panic errors in AMD's MCE grading x86/mce: Simplify AMD severity grading logic x86/MCE/AMD: Fix memory leak when threshold_create_bank() fails x86/mce: Avoid unnecessary padding in struct mce_bank
2022-05-23Merge tag 'x86_sev_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull AMD SEV-SNP support from Borislav Petkov: "The third AMD confidential computing feature called Secure Nested Paging. Add to confidential guests the necessary memory integrity protection against malicious hypervisor-based attacks like data replay, memory remapping and others, thus achieving a stronger isolation from the hypervisor. At the core of the functionality is a new structure called a reverse map table (RMP) with which the guest has a say in which pages get assigned to it and gets notified when a page which it owns, gets accessed/modified under the covers so that the guest can take an appropriate action. In addition, add support for the whole machinery needed to launch a SNP guest, details of which is properly explained in each patch. And last but not least, the series refactors and improves parts of the previous SEV support so that the new code is accomodated properly and not just bolted on" * tag 'x86_sev_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) x86/entry: Fixup objtool/ibt validation x86/sev: Mark the code returning to user space as syscall gap x86/sev: Annotate stack change in the #VC handler x86/sev: Remove duplicated assignment to variable info x86/sev: Fix address space sparse warning x86/sev: Get the AP jump table address from secrets page x86/sev: Add missing __init annotations to SEV init routines virt: sevguest: Rename the sevguest dir and files to sev-guest virt: sevguest: Change driver name to reflect generic SEV support x86/boot: Put globals that are accessed early into the .data section x86/boot: Add an efi.h header for the decompressor virt: sevguest: Fix bool function returning negative value virt: sevguest: Fix return value check in alloc_shared_pages() x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate() virt: sevguest: Add documentation for SEV-SNP CPUID Enforcement virt: sevguest: Add support to get extended report virt: sevguest: Add support to derive key virt: Add SEV-SNP guest driver x86/sev: Register SEV-SNP guest request platform device x86/sev: Provide support for SNP guest request NAEs ...
2022-05-23Merge tag 'x86-irq-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 PCI irq routing updates from Thomas Gleixner: - Cleanup and robustify the PCI interrupt routing table handling including proper range checks - Add support for Intel 82378ZB/82379AB, SiS85C497 PIRQ routers - Fix the ALi M1487 router handling - Handle the IRT routing table format in AMI BIOSes correctly * tag 'x86-irq-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/PCI: Fix coding style in PIRQ table verification x86/PCI: Fix ALi M1487 (IBC) PIRQ router link value interpretation x86/PCI: Add $IRT PIRQ routing table support x86/PCI: Handle PIRQ routing tables with no router device given x86/PCI: Add PIRQ routing table range checks x86/PCI: Add support for the SiS85C497 PIRQ router x86/PCI: Disambiguate SiS85C503 PIRQ router code entities x86/PCI: Handle IRQ swizzling with PIRQ routers x86/PCI: Also match function number in $PIR table x86/PCI: Include function number in $PIR table dump x86/PCI: Show the physical address of the $PIR table
2022-05-23Merge tag 'smp-core-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug updates from Thomas Gleixner: - Initialize the per-CPU structures during early boot so that the state is consistent from the very beginning. - Make the virtualization hotplug state handling more robust and let the core bringup CPUs which timed out in an earlier attempt again. - Make the x86/xen CPU state tracking consistent on a failed online attempt, so a consecutive bringup does not fall over the inconsistent state. * tag 'smp-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cpu/hotplug: Initialise all cpuhp_cpu_state structs earlier cpu/hotplug: Allow the CPU in CPU_UP_PREPARE state to be brought up again. x86/xen: Allow to retry if cpu_initialize_context() failed.
2022-05-23Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Daniel Borkmann says: ==================== pull-request: bpf-next 2022-05-23 We've added 113 non-merge commits during the last 26 day(s) which contain a total of 121 files changed, 7425 insertions(+), 1586 deletions(-). The main changes are: 1) Speed up symbol resolution for kprobes multi-link attachments, from Jiri Olsa. 2) Add BPF dynamic pointer infrastructure e.g. to allow for dynamically sized ringbuf reservations without extra memory copies, from Joanne Koong. 3) Big batch of libbpf improvements towards libbpf 1.0 release, from Andrii Nakryiko. 4) Add BPF link iterator to traverse links via seq_file ops, from Dmitrii Dolgov. 5) Add source IP address to BPF tunnel key infrastructure, from Kaixi Fan. 6) Refine unprivileged BPF to disable only object-creating commands, from Alan Maguire. 7) Fix JIT blinding of ld_imm64 when they point to subprogs, from Alexei Starovoitov. 8) Add BPF access to mptcp_sock structures and their meta data, from Geliang Tang. 9) Add new BPF helper for access to remote CPU's BPF map elements, from Feng Zhou. 10) Allow attaching 64-bit cookie to BPF link of fentry/fexit/fmod_ret, from Kui-Feng Lee. 11) Follow-ups to typed pointer support in BPF maps, from Kumar Kartikeya Dwivedi. 12) Add busy-poll test cases to the XSK selftest suite, from Magnus Karlsson. 13) Improvements in BPF selftest test_progs subtest output, from Mykola Lysenko. 14) Fill bpf_prog_pack allocator areas with illegal instructions, from Song Liu. 15) Add generic batch operations for BPF map-in-map cases, from Takshak Chahande. 16) Make bpf_jit_enable more user friendly when permanently on 1, from Tiezhu Yang. 17) Fix an array overflow in bpf_trampoline_get_progs(), from Yuntao Wang. ==================== Link: https://lore.kernel.org/r/20220523223805.27931-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-23bpf: Introduce bpf_arch_text_invalidate for bpf_prog_packSong Liu
Introduce bpf_arch_text_invalidate and use it to fill unused part of the bpf_prog_pack with illegal instructions when a BPF program is freed. Fixes: 57631054fae6 ("bpf: Introduce bpf_prog_pack allocator") Fixes: 33c9805860e5 ("bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220520235758.1858153-4-song@kernel.org
2022-05-23x86/alternative: Introduce text_poke_setSong Liu
Introduce a memset like API for text_poke. This will be used to fill the unused RX memory with illegal instructions. Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/bpf/20220520235758.1858153-3-song@kernel.org
2022-05-23Merge tag 'efi-next-for-v5.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Allow runtime services to be re-enabled at boot on RT kernels. - Provide access to secrets injected into the boot image by CoCo hypervisors (COnfidential COmputing) - Use DXE services on x86 to make the boot image executable after relocation, if needed. - Prefer mirrored memory for randomized allocations. - Only randomize the placement of the kernel image on arm64 if the loader has not already done so. - Add support for obtaining the boot hartid from EFI on RISC-V. * tag 'efi-next-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: riscv/efi_stub: Add support for RISCV_EFI_BOOT_PROTOCOL efi: stub: prefer mirrored memory for randomized allocations efi/arm64: libstub: run image in place if randomized by the loader efi: libstub: pass image handle to handle_kernel_image() efi: x86: Set the NX-compatibility flag in the PE header efi: libstub: ensure allocated memory to be executable efi: libstub: declare DXE services table efi: Add missing prototype for efi_capsule_setup_info docs: security: Add secrets/coco documentation efi: Register efi_secret platform device if EFI secret area is declared virt: Add efi_secret module to expose confidential computing secrets efi: Save location of EFI confidential computing area efi: Allow to enable EFI runtime services by default on RT
2022-05-23Merge branch 'pm-tools'Rafael J. Wysocki
Merge power management tools updates for 5.19-rc1: - Update turbostat to version 2022.04.16 including the following changes: * No build warnings with -Wextra (Len Brown). * Tweak --show and --hide capability (Len Brown). * Be more useful as non-root (Len Brown). * Fix ICX DRAM power numbers (Len Brown). * Fix dump for AMD cpus (Dan Merillat). * Add Power Limit4 support (Sumeet Pawnikar). * Print power values upto three decimal (Sumeet Pawnikar). * Allow -e for all names (Zephaniah E. Loss-Cutler-Hull). * Allow printing header every N iterations (Zephaniah E. Loss-Cutler-Hull). * Support thermal throttle count print (Chen Yu). * pm-tools: tools/power turbostat: version 2022.04.16 tools/power turbostat: No build warnings with -Wextra tools/power turbostat: be more useful as non-root tools/power turbostat: fix ICX DRAM power numbers tools/power turbostat: Support thermal throttle count print tools/power turbostat: Allow printing header every N iterations tools/power turbostat: Allow -e for all names. tools/power turbostat: print power values upto three decimal tools/power turbostat: Add Power Limit4 support tools/power turbostat: fix dump for AMD cpus tools/power turbostat: tweak --show and --hide capability
2022-05-23Merge branches 'pm-core', 'pm-sleep' and 'powercap'Rafael J. Wysocki
Merge PM core changes, updates related to system sleep and power capping updates for 5.19-rc1: - Export dev_pm_ops instead of suspend() and resume() in the IIO chemical scd30 driver (Jonathan Cameron). - Add namespace variants of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and PM-runtime counterparts (Jonathan Cameron). - Move symbol exports in the IIO chemical scd30 driver into the IIO_SCD30 namespace (Jonathan Cameron). - Avoid device PM-runtime usage count underflows (Rafael Wysocki). - Allow dynamic debug to control printing of PM messages (David Cohen). - Fix some kernel-doc comments in hibernation code (Yang Li, Haowen Bai). - Preserve ACPI-table override during hibernation (Amadeusz Sławiński). - Improve support for suspend-to-RAM for PSCI OSI mode (Ulf Hansson). - Make Intel RAPL power capping driver support the RaptorLake and AlderLake N processors (Zhang Rui, Sumeet Pawnikar). - Remove redundant store to value after multiply in the RAPL power capping driver (Colin Ian King). * pm-core: PM: runtime: Avoid device usage count underflows iio: chemical: scd30: Move symbol exports into IIO_SCD30 namespace PM: core: Add NS varients of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and runtime pm equiv iio: chemical: scd30: Export dev_pm_ops instead of suspend() and resume() * pm-sleep: cpuidle: PSCI: Improve support for suspend-to-RAM for PSCI OSI mode PM: runtime: Allow to call __pm_runtime_set_status() from atomic context PM: hibernate: Don't mark comment as kernel-doc x86/ACPI: Preserve ACPI-table override during hibernation PM: hibernate: Fix some kernel-doc comments PM: sleep: enable dynamic debug support within pm_pr_dbg() PM: sleep: Narrow down -DDEBUG on kernel/power/ files * powercap: powercap: intel_rapl: remove redundant store to value after multiply powercap: intel_rapl: add support for ALDERLAKE_N powercap: RAPL: Add Power Limit4 support for RaptorLake powercap: intel_rapl: add support for RaptorLake
2022-05-23Merge branches 'acpi-apei', 'acpi-dptf', 'acpi-x86' and 'acpi-docs'Rafael J. Wysocki
Merge APEI material, changes related to DPTF, ACPI-related x86 cleanup and documentation improvement for 5.19-rc1: - Fix missing ERST record ID in the APEI code (Liu Xinpeng). - Make APEI error injection to refuse to inject into the zero page (Tony Luck). - Correct description of INT3407 / INT3532 DPTF attributes in sysfs (Sumeet Pawnikar). - Add support for high frequency impedance notification to the DPTF driver (Sumeet Pawnikar). - Make mp_config_acpi_gsi() a void function (Li kunyu). - Unify Package () representation for properties in the ACPI device properties documentation (Andy Shevchenko). * acpi-apei: ACPI, APEI, EINJ: Refuse to inject into the zero page ACPI: APEI: Fix missing ERST record id * acpi-dptf: ACPI: DPTF: Add support for high frequency impedance notification ACPI: DPTF: Correct description of INT3407 / INT3532 attributes * acpi-x86: x86: ACPI: Make mp_config_acpi_gsi() a void function * acpi-docs: ACPI: docs: enumeration: Unify Package () for properties (part 2)
2022-05-21KVM: x86/speculation: Disable Fill buffer clear within guestsPawan Gupta
The enumeration of MD_CLEAR in CPUID(EAX=7,ECX=0).EDX{bit 10} is not an accurate indicator on all CPUs of whether the VERW instruction will overwrite fill buffers. FB_CLEAR enumeration in IA32_ARCH_CAPABILITIES{bit 17} covers the case of CPUs that are not vulnerable to MDS/TAA, indicating that microcode does overwrite fill buffers. Guests running in VMM environments may not be aware of all the capabilities/vulnerabilities of the host CPU. Specifically, a guest may apply MDS/TAA mitigations when a virtual CPU is enumerated as vulnerable to MDS/TAA even when the physical CPU is not. On CPUs that enumerate FB_CLEAR_CTRL the VMM may set FB_CLEAR_DIS to skip overwriting of fill buffers by the VERW instruction. This is done by setting FB_CLEAR_DIS during VMENTER and resetting on VMEXIT. For guests that enumerate FB_CLEAR (explicitly asking for fill buffer clear capability) the VMM will not use FB_CLEAR_DIS. Irrespective of guest state, host overwrites CPU buffers before VMENTER to protect itself from an MMIO capable guest, as part of mitigation for MMIO Stale Data vulnerabilities. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/speculation/mmio: Reuse SRBDS mitigation for SBDSPawan Gupta
The Shared Buffers Data Sampling (SBDS) variant of Processor MMIO Stale Data vulnerabilities may expose RDRAND, RDSEED and SGX EGETKEY data. Mitigation for this is added by a microcode update. As some of the implications of SBDS are similar to SRBDS, SRBDS mitigation infrastructure can be leveraged by SBDS. Set X86_BUG_SRBDS and use SRBDS mitigation. Mitigation is enabled by default; use srbds=off to opt-out. Mitigation status can be checked from below file: /sys/devices/system/cpu/vulnerabilities/srbds Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/speculation/srbds: Update SRBDS mitigation selectionPawan Gupta
Currently, Linux disables SRBDS mitigation on CPUs not affected by MDS and have the TSX feature disabled. On such CPUs, secrets cannot be extracted from CPU fill buffers using MDS or TAA. Without SRBDS mitigation, Processor MMIO Stale Data vulnerabilities can be used to extract RDRAND, RDSEED, and EGETKEY data. Do not disable SRBDS mitigation by default when CPU is also affected by Processor MMIO Stale Data vulnerabilities. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale DataPawan Gupta
Add the sysfs reporting file for Processor MMIO Stale Data vulnerability. It exposes the vulnerability and mitigation state similar to the existing files for the other hardware vulnerabilities. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/speculation/mmio: Enable CPU Fill buffer clearing on idlePawan Gupta
When the CPU is affected by Processor MMIO Stale Data vulnerabilities, Fill Buffer Stale Data Propagator (FBSDP) can propagate stale data out of Fill buffer to uncore buffer when CPU goes idle. Stale data can then be exploited with other variants using MMIO operations. Mitigate it by clearing the Fill buffer before entering idle state. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/bugs: Group MDS, TAA & Processor MMIO Stale Data mitigationsPawan Gupta
MDS, TAA and Processor MMIO Stale Data mitigations rely on clearing CPU buffers. Moreover, status of these mitigations affects each other. During boot, it is important to maintain the order in which these mitigations are selected. This is especially true for md_clear_update_mitigation() that needs to be called after MDS, TAA and Processor MMIO Stale Data mitigation selection is done. Introduce md_clear_select_mitigation(), and select all these mitigations from there. This reflects relationships between these mitigations and ensures proper ordering. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21x86/speculation/mmio: Add mitigation for Processor MMIO Stale DataPawan Gupta
Processor MMIO Stale Data is a class of vulnerabilities that may expose data after an MMIO operation. For details please refer to Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst. These vulnerabilities are broadly categorized as: Device Register Partial Write (DRPW): Some endpoint MMIO registers incorrectly handle writes that are smaller than the register size. Instead of aborting the write or only copying the correct subset of bytes (for example, 2 bytes for a 2-byte write), more bytes than specified by the write transaction may be written to the register. On some processors, this may expose stale data from the fill buffers of the core that created the write transaction. Shared Buffers Data Sampling (SBDS): After propagators may have moved data around the uncore and copied stale data into client core fill buffers, processors affected by MFBDS can leak data from the fill buffer. Shared Buffers Data Read (SBDR): It is similar to Shared Buffer Data Sampling (SBDS) except that the data is directly read into the architectural software-visible state. An attacker can use these vulnerabilities to extract data from CPU fill buffers using MDS and TAA methods. Mitigate it by clearing the CPU fill buffers using the VERW instruction before returning to a user or a guest. On CPUs not affected by MDS and TAA, user application cannot sample data from CPU fill buffers using MDS or TAA. A guest with MMIO access can still use DRPW or SBDR to extract data architecturally. Mitigate it with VERW instruction to clear fill buffers before VMENTER for MMIO capable guests. Add a kernel parameter mmio_stale_data={off|full|full,nosmt} to control the mitigation. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de>