aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/tools/perf/scripts/python/export-to-postgresql.py (unfollow)
AgeCommit message (Collapse)AuthorFilesLines
2025-03-14KVM: x86: Add infrastructure for secure TSCIsaku Yamahata2-2/+10
Add guest_tsc_protected member to struct kvm_arch_vcpu and prohibit changing TSC offset/multiplier when guest_tsc_protected is true. X86 confidential computing technology defines protected guest TSC so that the VMM can't change the TSC offset/multiplier once vCPU is initialized. SEV-SNP defines Secure TSC as optional, whereas TDX mandates it. KVM has common logic on x86 that tries to guess or adjust TSC offset/multiplier for better guest TSC and TSC interrupt latency at KVM vCPU creation (kvm_arch_vcpu_postcreate()), vCPU migration over pCPU (kvm_arch_vcpu_load()), vCPU TSC device attributes (kvm_arch_tsc_set_attr()) and guest/host writing to TSC or TSC adjust MSR (kvm_set_msr_common()). The current x86 KVM implementation conflicts with protected TSC because the VMM can't change the TSC offset/multiplier. Because KVM emulates the TSC timer or the TSC deadline timer with the TSC offset/multiplier, the TSC timer interrupts is injected to the guest at the wrong time if the KVM TSC offset is different from what the TDX module determined. Originally this issue was found by cyclic test of rt-test [1] as the latency in TDX case is worse than VMX value + TDX SEAMCALL overhead. It turned out that the KVM TSC offset is different from what the TDX module determines. Disable or ignore the KVM logic to change/adjust the TSC offset/multiplier somehow, thus keeping the KVM TSC offset/multiplier the same as the value of the TDX module. Writes to MSR_IA32_TSC are also blocked as they amount to a change in the TSC offset. [1] https://git.kernel.org/pub/scm/utils/rt-tests/rt-tests.git Reported-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Message-ID: <3a7444aec08042fe205666864b6858910e86aa98.1728719037.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-14KVM: x86: Push down setting vcpu.arch.user_set_tscIsaku Yamahata1-6/+6
Push down setting vcpu.arch.user_set_tsc to true from kvm_synchronize_tsc() to __kvm_synchronize_tsc() so that the two callers don't have to modify user_set_tsc directly as preparation. Later, prohibit changing TSC synchronization for TDX guests to modify __kvm_synchornize_tsc() change. We don't want to touch caller sites not to change user_set_tsc. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Message-ID: <62b1a7a35d6961844786b6e47e8ecb774af7a228.1728719037.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-14KVM: x86: move vm_destroy callback at end of kvm_arch_destroy_vmPaolo Bonzini1-1/+1
TDX needs to free the TDR control structures last, after all paging structures have been torn down; move the vm_destroy callback at a suitable place. The new place is also okay for AMD; the main difference is that the MMU has been torn down and, if anything, that is better done before the SNP ASID is released. Extracted from a patch by Yan Zhao. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-04KVM: x86: Explicitly zero EAX and EBX when PERFMON_V2 isn't supported by KVMXiaoyao Li1-1/+1
Fix a goof where KVM sets CPUID.0x80000022.EAX to CPUID.0x80000022.EBX instead of zeroing both when PERFMON_V2 isn't supported by KVM. In practice, barring a buggy CPU (or vCPU model when running nested) only the !enable_pmu case is affected, as KVM always supports PERFMON_V2 if it's available in hardware, i.e. CPUID.0x80000022.EBX will be '0' if PERFMON_V2 is unsupported. For the !enable_pmu case, the bug is relatively benign as KVM will refuse to enable PMU capabilities, but a VMM that reflects KVM's supported CPUID into the guest could inadvertently induce #GPs in the guest due to advertising support for MSRs that KVM refuses to emulate. Fixes: 94cdeebd8211 ("KVM: x86/cpuid: Add AMD CPUID ExtPerfMonAndDbg leaf 0x80000022") Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20250304082314.472202-3-xiaoyao.li@intel.com [sean: massage shortlog and changelog, tag for stable] Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-03KVM: selftests: Fix printf() format goof in SEV smoke testSean Christopherson1-1/+2
Print out the index of mismatching XSAVE bytes using unsigned decimal format. Some versions of clang complain about trying to print an integer as an unsigned char. x86/sev_smoke_test.c:55:51: error: format specifies type 'unsigned char' but the argument has type 'int' [-Werror,-Wformat] Fixes: 8c53183dbaa2 ("selftests: kvm: add test for transferring FPU state into VMSA") Link: https://lore.kernel.org/r/20250228233852.3855676-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-03KVM: selftests: Ensure all vCPUs hit -EFAULT during initial RO stageSean Christopherson1-8/+13
During the initial mprotect(RO) stage of mmu_stress_test, keep vCPUs spinning until all vCPUs have hit -EFAULT, i.e. until all vCPUs have tried to write to a read-only page. If a vCPU manages to complete an entire iteration of the loop without hitting a read-only page, *and* the vCPU observes mprotect_ro_done before starting a second iteration, then the vCPU will prematurely fall through to GUEST_SYNC(3) (on x86 and arm64) and get out of sequence. Replace the "do-while (!r)" loop around the associated _vcpu_run() with a single invocation, as barring a KVM bug, the vCPU is guaranteed to hit -EFAULT, and retrying on success is super confusion, hides KVM bugs, and complicates this fix. The do-while loop was semi-unintentionally added specifically to fudge around a KVM x86 bug, and said bug is unhittable without modifying the test to force x86 down the !(x86||arm64) path. On x86, if forced emulation is enabled, vcpu_arch_put_guest() may trigger emulation of the store to memory. Due a (very, very) longstanding bug in KVM x86's emulator, emulate writes to guest memory that fail during __kvm_write_guest_page() unconditionally return KVM_EXIT_MMIO. While that is desirable in the !memslot case, it's wrong in this case as the failure happens due to __copy_to_user() hitting a read-only page, not an emulated MMIO region. But as above, x86 only uses vcpu_arch_put_guest() if the __x86_64__ guards are clobbered to force x86 down the common path, and of course the unexpected MMIO is a KVM bug, i.e. *should* cause a test failure. Fixes: b6c304aec648 ("KVM: selftests: Verify KVM correctly handles mprotect(PROT_READ)") Reported-by: Yan Zhao <yan.y.zhao@intel.com> Closes: https://lore.kernel.org/all/20250208105318.16861-1-yan.y.zhao@intel.com Debugged-by: Yan Zhao <yan.y.zhao@intel.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Tested-by: Yan Zhao <yan.y.zhao@intel.com> Link: https://lore.kernel.org/r/20250228230804.3845860-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-03KVM: SVM: Don't rely on DebugSwap to restore host DR0..DR3Sean Christopherson1-9/+12
Never rely on the CPU to restore/load host DR0..DR3 values, even if the CPU supports DebugSwap, as there are no guarantees that SNP guests will actually enable DebugSwap on APs. E.g. if KVM were to rely on the CPU to load DR0..DR3 and skipped them during hw_breakpoint_restore(), KVM would run with clobbered-to-zero DRs if an SNP guest created APs without DebugSwap enabled. Update the comment to explain the dangers, and hopefully prevent breaking KVM in the future. Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250227012541.3234589-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-03KVM: SVM: Save host DR masks on CPUs with DebugSwapSean Christopherson1-3/+10
When running SEV-SNP guests on a CPU that supports DebugSwap, always save the host's DR0..DR3 mask MSR values irrespective of whether or not DebugSwap is enabled, to ensure the host values aren't clobbered by the CPU. And for now, also save DR0..DR3, even though doing so isn't necessary (see below). SVM_VMGEXIT_AP_CREATE is deeply flawed in that it allows the *guest* to create a VMSA with guest-controlled SEV_FEATURES. A well behaved guest can inform the hypervisor, i.e. KVM, of its "requested" features, but on CPUs without ALLOWED_SEV_FEATURES support, nothing prevents the guest from lying about which SEV features are being enabled (or not!). If a misbehaving guest enables DebugSwap in a secondary vCPU's VMSA, the CPU will load the DR0..DR3 mask MSRs on #VMEXIT, i.e. will clobber the MSRs with '0' if KVM doesn't save its desired value. Note, DR0..DR3 themselves are "ok", as DR7 is reset on #VMEXIT, and KVM restores all DRs in common x86 code as needed via hw_breakpoint_restore(). I.e. there is no risk of host DR0..DR3 being clobbered (when it matters). However, there is a flaw in the opposite direction; because the guest can lie about enabling DebugSwap, i.e. can *disable* DebugSwap without KVM's knowledge, KVM must not rely on the CPU to restore DRs. Defer fixing that wart, as it's more of a documentation issue than a bug in the code. Note, KVM added support for DebugSwap on commit d1f85fbe836e ("KVM: SEV: Enable data breakpoints in SEV-ES"), but that is not an appropriate Fixes, as the underlying flaw exists in hardware, not in KVM. I.e. all kernels that support SEV-SNP need to be patched, not just kernels with KVM's full support for DebugSwap (ignoring that DebugSwap support landed first). Opportunistically fix an incorrect statement in the comment; on CPUs without DebugSwap, the CPU does NOT save or load debug registers, i.e. Fixes: e366f92ea99e ("KVM: SEV: Support SEV-SNP AP Creation NAE event") Cc: stable@vger.kernel.org Cc: Naveen N Rao <naveen@kernel.org> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Alexey Kardashevskiy <aik@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250227012541.3234589-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-02KVM: arm64: Initialize SCTLR_EL1 in __kvm_hyp_init_cpu()Ahmed Genidi4-8/+5
When KVM is in protected mode, host calls to PSCI are proxied via EL2, and cold entries from CPU_ON, CPU_SUSPEND, and SYSTEM_SUSPEND bounce through __kvm_hyp_init_cpu() at EL2 before entering the host kernel's entry point at EL1. While __kvm_hyp_init_cpu() initializes SPSR_EL2 for the exception return to EL1, it does not initialize SCTLR_EL1. Due to this, it's possible to enter EL1 with SCTLR_EL1 in an UNKNOWN state. In practice this has been seen to result in kernel crashes after CPU_ON as a result of SCTLR_EL1.M being 1 in violation of the initial core configuration specified by PSCI. Fix this by initializing SCTLR_EL1 for cold entry to the host kernel. As it's necessary to write to SCTLR_EL12 in VHE mode, this initialization is moved into __kvm_host_psci_cpu_entry() where we can use write_sysreg_el1(). The remnants of the '__init_el2_nvhe_prepare_eret' macro are folded into its only caller, as this is clearer than having the macro. Fixes: cdf367192766ad11 ("KVM: arm64: Intercept host's CPU_ON SMCs") Reported-by: Leo Yan <leo.yan@arm.com> Signed-off-by: Ahmed Genidi <ahmed.genidi@arm.com> [ Mark: clarify commit message, handle E2H, move to C, remove macro ] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ahmed Genidi <ahmed.genidi@arm.com> Cc: Ben Horgan <ben.horgan@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Will Deacon <will@kernel.org> Reviewed-by: Leo Yan <leo.yan@arm.com> Link: https://lore.kernel.org/r/20250227180526.1204723-3-mark.rutland@arm.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-03-02KVM: arm64: Initialize HCR_EL2.E2H earlyMark Rutland3-19/+34
On CPUs without FEAT_E2H0, HCR_EL2.E2H is RES1, but may reset to an UNKNOWN value out of reset and consequently may not read as 1 unless it has been explicitly initialized. We handled this for the head.S boot code in commits: 3944382fa6f22b54 ("arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is negative") b3320142f3db9b3f ("arm64: Fix early handling of FEAT_E2H0 not being implemented") Unfortunately, we forgot to apply a similar fix to the KVM PSCI entry points used when relaying CPU_ON, CPU_SUSPEND, and SYSTEM SUSPEND. When KVM is entered via these entry points, the value of HCR_EL2.E2H may be consumed before it has been initialized (e.g. by the 'init_el2_state' macro). Initialize HCR_EL2.E2H early in these paths such that it can be consumed reliably. The existing code in head.S is factored out into a new 'init_el2_hcr' macro, and this is used in the __kvm_hyp_init_cpu() function common to all the relevant PSCI entry points. For clarity, I've tweaked the assembly used to check whether ID_AA64MMFR4_EL1.E2H0 is negative. The bitfield is extracted as a signed value, and this is checked with a signed-greater-or-equal (GE) comparison. As the hyp code will reconfigure HCR_EL2 later in ___kvm_hyp_init(), all bits other than E2H are initialized to zero in __kvm_hyp_init_cpu(). Fixes: 3944382fa6f22b54 ("arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is negative") Fixes: b3320142f3db9b3f ("arm64: Fix early handling of FEAT_E2H0 not being implemented") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ahmed Genidi <ahmed.genidi@arm.com> Cc: Ben Horgan <ben.horgan@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20250227180526.1204723-2-mark.rutland@arm.com [maz: fixed LT->GE thinko] Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-03-01kvm: retry nx_huge_page_recovery_thread creationKeith Busch2-19/+38
A VMM may send a non-fatal signal to its threads, including vCPU tasks, at any time, and thus may signal vCPU tasks during KVM_RUN. If a vCPU task receives the signal while its trying to spawn the huge page recovery vhost task, then KVM_RUN will fail due to copy_process() returning -ERESTARTNOINTR. Rework call_once() to mark the call complete if and only if the called function succeeds, and plumb the function's true error code back to the call_once() invoker. This provides userspace with the correct, non-fatal error code so that the VMM doesn't terminate the VM on -ENOMEM, and allows subsequent KVM_RUN a succeed by virtue of retrying creation of the NX huge page task. Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> [implemented the kvm user side] Signed-off-by: Keith Busch <kbusch@kernel.org> Message-ID: <20250227230631.303431-3-kbusch@meta.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-01vhost: return task creation error instead of NULLKeith Busch3-4/+4
Lets callers distinguish why the vhost task creation failed. No one currently cares why it failed, so no real runtime change from this patch, but that will not be the case for long. Signed-off-by: Keith Busch <kbusch@kernel.org> Message-ID: <20250227230631.303431-2-kbusch@meta.com> Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-28KVM: x86: Snapshot the host's DEBUGCTL after disabling IRQsSean Christopherson1-1/+2
Snapshot the host's DEBUGCTL after disabling IRQs, as perf can toggle debugctl bits from IRQ context, e.g. when enabling/disabling events via smp_call_function_single(). Taking the snapshot (long) before IRQs are disabled could result in KVM effectively clobbering DEBUGCTL due to using a stale snapshot. Cc: stable@vger.kernel.org Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: SVM: Manually context switch DEBUGCTL if LBR virtualization is disabledSean Christopherson1-0/+14
Manually load the guest's DEBUGCTL prior to VMRUN (and restore the host's value on #VMEXIT) if it diverges from the host's value and LBR virtualization is disabled, as hardware only context switches DEBUGCTL if LBR virtualization is fully enabled. Running the guest with the host's value has likely been mildly problematic for quite some time, e.g. it will result in undesirable behavior if BTF diverges (with the caveat that KVM now suppresses guest BTF due to lack of support). But the bug became fatal with the introduction of Bus Lock Trap ("Detect" in kernel paralance) support for AMD (commit 408eb7417a92 ("x86/bus_lock: Add support for AMD")), as a bus lock in the guest will trigger an unexpected #DB. Note, suppressing the bus lock #DB, i.e. simply resuming the guest without injecting a #DB, is not an option. It wouldn't address the general issue with DEBUGCTL, e.g. for things like BTF, and there are other guest-visible side effects if BusLockTrap is left enabled. If BusLockTrap is disabled, then DR6.BLD is reserved-to-1; any attempts to clear it by software are ignored. But if BusLockTrap is enabled, software can clear DR6.BLD: Software enables bus lock trap by setting DebugCtl MSR[BLCKDB] (bit 2) to 1. When bus lock trap is enabled, ... The processor indicates that this #DB was caused by a bus lock by clearing DR6[BLD] (bit 11). DR6[11] previously had been defined to be always 1. and clearing DR6.BLD is "sticky" in that it's not set (i.e. lowered) by other #DBs: All other #DB exceptions leave DR6[BLD] unmodified E.g. leaving BusLockTrap enable can confuse a legacy guest that writes '0' to reset DR6. Reported-by: rangemachine@gmail.com Reported-by: whanos@sergal.fun Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219787 Closes: https://lore.kernel.org/all/bug-219787-28872@https.bugzilla.kernel.org%2F Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: stable@vger.kernel.org Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: x86: Snapshot the host's DEBUGCTL in common x86Sean Christopherson4-8/+4
Move KVM's snapshot of DEBUGCTL to kvm_vcpu_arch and take the snapshot in common x86, so that SVM can also use the snapshot. Opportunistically change the field to a u64. While bits 63:32 are reserved on AMD, not mentioned at all in Intel's SDM, and managed as an "unsigned long" by the kernel, DEBUGCTL is an MSR and therefore a 64-bit value. Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Cc: stable@vger.kernel.org Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: SVM: Suppress DEBUGCTL.BTF on AMDSean Christopherson2-1/+10
Mark BTF as reserved in DEBUGCTL on AMD, as KVM doesn't actually support BTF, and fully enabling BTF virtualization is non-trivial due to interactions with the emulator, guest_debug, #DB interception, nested SVM, etc. Don't inject #GP if the guest attempts to set BTF, as there's no way to communicate lack of support to the guest, and instead suppress the flag and treat the WRMSR as (partially) unsupported. In short, make KVM behave the same on AMD and Intel (VMX already squashes BTF). Note, due to other bugs in KVM's handling of DEBUGCTL, the only way BTF has "worked" in any capacity is if the guest simultaneously enables LBRs. Reported-by: Ravi Bangoria <ravi.bangoria@amd.com> Cc: stable@vger.kernel.org Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: SVM: Drop DEBUGCTL[5:2] from guest's effective valueSean Christopherson2-1/+13
Drop bits 5:2 from the guest's effective DEBUGCTL value, as AMD changed the architectural behavior of the bits and broke backwards compatibility. On CPUs without BusLockTrap (or at least, in APMs from before ~2023), bits 5:2 controlled the behavior of external pins: Performance-Monitoring/Breakpoint Pin-Control (PBi)—Bits 5:2, read/write. Software uses thesebits to control the type of information reported by the four external performance-monitoring/breakpoint pins on the processor. When a PBi bit is cleared to 0, the corresponding external pin (BPi) reports performance-monitor information. When a PBi bit is set to 1, the corresponding external pin (BPi) reports breakpoint information. With the introduction of BusLockTrap, presumably to be compatible with Intel CPUs, AMD redefined bit 2 to be BLCKDB: Bus Lock #DB Trap (BLCKDB)—Bit 2, read/write. Software sets this bit to enable generation of a #DB trap following successful execution of a bus lock when CPL is > 0. and redefined bits 5:3 (and bit 6) as "6:3 Reserved MBZ". Ideally, KVM would treat bits 5:2 as reserved. Defer that change to a feature cleanup to avoid breaking existing guest in LTS kernels. For now, drop the bits to retain backwards compatibility (of a sort). Note, dropping bits 5:2 is still a guest-visible change, e.g. if the guest is enabling LBRs *and* the legacy PBi bits, then the state of the PBi bits is visible to the guest, whereas now the guest will always see '0'. Reported-by: Ravi Bangoria <ravi.bangoria@amd.com> Cc: stable@vger.kernel.org Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Link: https://lore.kernel.org/r/20250227222411.3490595-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: selftests: Assert that STI blocking isn't set after event injectionSean Christopherson1-0/+2
Add an L1 (guest) assert to the nested exceptions test to verify that KVM doesn't put VMRUN in an STI shadow (AMD CPUs bleed the shadow into the guest's int_state if a #VMEXIT occurs before VMRUN fully completes). Add a similar assert to the VMX side as well, because why not. Reviewed-by: Jim Mattson <jmattson@google.com> Link: https://lore.kernel.org/r/20250224165442.2338294-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28KVM: SVM: Set RFLAGS.IF=1 in C code, to get VMRUN out of the STI shadowSean Christopherson2-9/+15
Enable/disable local IRQs, i.e. set/clear RFLAGS.IF, in the common svm_vcpu_enter_exit() just after/before guest_state_{enter,exit}_irqoff() so that VMRUN is not executed in an STI shadow. AMD CPUs have a quirk (some would say "bug"), where the STI shadow bleeds into the guest's intr_state field if a #VMEXIT occurs during injection of an event, i.e. if the VMRUN doesn't complete before the subsequent #VMEXIT. The spurious "interrupts masked" state is relatively benign, as it only occurs during event injection and is transient. Because KVM is already injecting an event, the guest can't be in HLT, and if KVM is querying IRQ blocking for injection, then KVM would need to force an immediate exit anyways since injecting multiple events is impossible. However, because KVM copies int_state verbatim from vmcb02 to vmcb12, the spurious STI shadow is visible to L1 when running a nested VM, which can trip sanity checks, e.g. in VMware's VMM. Hoist the STI+CLI all the way to C code, as the aforementioned calls to guest_state_{enter,exit}_irqoff() already inform lockdep that IRQs are enabled/disabled, and taking a fault on VMRUN with RFLAGS.IF=1 is already possible. I.e. if there's kernel code that is confused by running with RFLAGS.IF=1, then it's already a problem. In practice, since GIF=0 also blocks NMIs, the only change in exposure to non-KVM code (relative to surrounding VMRUN with STI+CLI) is exception handling code, and except for the kvm_rebooting=1 case, all exception in the core VM-Enter/VM-Exit path are fatal. Use the "raw" variants to enable/disable IRQs to avoid tracing in the "no instrumentation" code; the guest state helpers also take care of tracing IRQ state. Oppurtunstically document why KVM needs to do STI in the first place. Reported-by: Doug Covelli <doug.covelli@broadcom.com> Closes: https://lore.kernel.org/all/CADH9ctBs1YPmE4aCfGPNBwA10cA8RuAk2gO7542DjMZgs4uzJQ@mail.gmail.com Fixes: f14eec0a3203 ("KVM: SVM: move more vmentry code to assembly") Cc: stable@vger.kernel.org Reviewed-by: Jim Mattson <jmattson@google.com> Link: https://lore.kernel.org/r/20250224165442.2338294-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-26KVM: nVMX: Process events on nested VM-Exit if injectable IRQ or NMI is pendingSean Christopherson1-0/+11
Process pending events on nested VM-Exit if the vCPU has an injectable IRQ or NMI, as the event may have become pending while L2 was active, i.e. may not be tracked in the context of vmcs01. E.g. if L1 has passed its APIC through to L2 and an IRQ arrives while L2 is active, then KVM needs to request an IRQ window prior to running L1, otherwise delivery of the IRQ will be delayed until KVM happens to process events for some other reason. The missed failure is detected by vmx_apic_passthrough_tpr_threshold_test in KVM-Unit-Tests, but has effectively been masked due to a flaw in KVM's PIC emulation that causes KVM to make spurious KVM_REQ_EVENT requests (and apparently no one ever ran the test with split IRQ chips). Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250224235542.2562848-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-26KVM: x86: Free vCPUs before freeing VM stateSean Christopherson1-1/+1
Free vCPUs before freeing any VM state, as both SVM and VMX may access VM state when "freeing" a vCPU that is currently "in" L2, i.e. that needs to be kicked out of nested guest mode. Commit 6fcee03df6a1 ("KVM: x86: avoid loading a vCPU after .vm_destroy was called") partially fixed the issue, but for unknown reasons only moved the MMU unloading before VM destruction. Complete the change, and free all vCPU state prior to destroying VM state, as nVMX accesses even more state than nSVM. In addition to the AVIC, KVM can hit a use-after-free on MSR filters: kvm_msr_allowed+0x4c/0xd0 __kvm_set_msr+0x12d/0x1e0 kvm_set_msr+0x19/0x40 load_vmcs12_host_state+0x2d8/0x6e0 [kvm_intel] nested_vmx_vmexit+0x715/0xbd0 [kvm_intel] nested_vmx_free_vcpu+0x33/0x50 [kvm_intel] vmx_free_vcpu+0x54/0xc0 [kvm_intel] kvm_arch_vcpu_destroy+0x28/0xf0 kvm_vcpu_destroy+0x12/0x50 kvm_arch_destroy_vm+0x12c/0x1c0 kvm_put_kvm+0x263/0x3c0 kvm_vm_release+0x21/0x30 and an upcoming fix to process injectable interrupts on nested VM-Exit will access the PIC: BUG: kernel NULL pointer dereference, address: 0000000000000090 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page CPU: 23 UID: 1000 PID: 2658 Comm: kvm-nx-lpage-re RIP: 0010:kvm_cpu_has_extint+0x2f/0x60 [kvm] Call Trace: <TASK> kvm_cpu_has_injectable_intr+0xe/0x60 [kvm] nested_vmx_vmexit+0x2d7/0xdf0 [kvm_intel] nested_vmx_free_vcpu+0x40/0x50 [kvm_intel] vmx_vcpu_free+0x2d/0x80 [kvm_intel] kvm_arch_vcpu_destroy+0x2d/0x130 [kvm] kvm_destroy_vcpus+0x8a/0x100 [kvm] kvm_arch_destroy_vm+0xa7/0x1d0 [kvm] kvm_destroy_vm+0x172/0x300 [kvm] kvm_vcpu_release+0x31/0x50 [kvm] Inarguably, both nSVM and nVMX need to be fixed, but punt on those cleanups for the moment. Conceptually, vCPUs should be freed before VM state. Assets like the I/O APIC and PIC _must_ be allocated before vCPUs are created, so it stands to reason that they must be freed _after_ vCPUs are destroyed. Reported-by: Aaron Lewis <aaronlewis@google.com> Closes: https://lore.kernel.org/all/20240703175618.2304869-2-aaronlewis@google.com Cc: Jim Mattson <jmattson@google.com> Cc: Yan Zhao <yan.y.zhao@intel.com> Cc: Rick P Edgecombe <rick.p.edgecombe@intel.com> Cc: Kai Huang <kai.huang@intel.com> Cc: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250224235542.2562848-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-21riscv: KVM: Remove unnecessary vcpu kickBillXiang1-1/+0
Remove the unnecessary kick to the vCPU after writing to the vs_file of IMSIC in kvm_riscv_vcpu_aia_imsic_inject. For vCPUs that are running, writing to the vs_file directly forwards the interrupt as an MSI to them and does not need an extra kick. For vCPUs that are descheduled after emulating WFI, KVM will enable the guest external interrupt for that vCPU in kvm_riscv_aia_wakeon_hgei. This means that writing to the vs_file will cause a guest external interrupt, which will cause KVM to wake up the vCPU in hgei_interrupt to handle the interrupt properly. Signed-off-by: BillXiang <xiangwencheng@lanxincomputing.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Radim Krčmář <rkrcmar@ventanamicro.com> Link: https://lore.kernel.org/r/20250221104538.2147-1-xiangwencheng@lanxincomputing.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-20KVM: arm64: Ensure a VMID is allocated before programming VTTBR_EL2Oliver Upton3-21/+14
Vladimir reports that a race condition to attach a VMID to a stage-2 MMU sometimes results in a vCPU entering the guest with a VMID of 0: | CPU1 | CPU2 | | | | kvm_arch_vcpu_ioctl_run | | vcpu_load <= load VTTBR_EL2 | | kvm_vmid->id = 0 | | | kvm_arch_vcpu_ioctl_run | | vcpu_load <= load VTTBR_EL2 | | with kvm_vmid->id = 0| | kvm_arm_vmid_update <= allocates fresh | | kvm_vmid->id and | | reload VTTBR_EL2 | | | | | kvm_arm_vmid_update <= observes that kvm_vmid->id | | already allocated, | | skips reload VTTBR_EL2 Oh yeah, it's as bad as it looks. Remember that VHE loads the stage-2 MMU eagerly but a VMID only gets attached to the MMU later on in the KVM_RUN loop. Even in the "best case" where VTTBR_EL2 correctly gets reprogrammed before entering the EL1&0 regime, there is a period of time where hardware is configured with VMID 0. That's completely insane. So, rather than decorating the 'late' binding with another hack, just allocate the damn thing up front. Attaching a VMID from vcpu_load() is still rollover safe since (surprise!) it'll always get called after a vCPU was preempted. Excuse me while I go find a brown paper bag. Cc: stable@vger.kernel.org Fixes: 934bf871f011 ("KVM: arm64: Load the stage-2 MMU context in kvm_vcpu_load_vhe()") Reported-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20250219220737.130842-1-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-19KVM: arm64: Fix tcr_el2 initialisation in hVHE modeWill Deacon2-9/+8
When not running in VHE mode, cpu_prepare_hyp_mode() computes the value of TCR_EL2 using the host's TCR_EL1 settings as a starting point. For nVHE, this amounts to masking out everything apart from the TG0, SH0, ORGN0, IRGN0 and T0SZ fields before setting the RES1 bits, shifting the IPS field down to the PS field and setting DS if LPA2 is enabled. Unfortunately, for hVHE, things go slightly wonky: EPD1 is correctly set to disable walks via TTBR1_EL2 but then the T1SZ and IPS fields are corrupted when we mistakenly attempt to initialise the PS and DS fields in their E2H=0 positions. Furthermore, many fields are retained from TCR_EL1 which should not be propagated to TCR_EL2. Notably, this means we can end up with A1 set despite not initialising TTBR1_EL2 at all. This has been shown to cause unexpected translation faults at EL2 with pKVM due to TLB invalidation not taking effect when running with a non-zero ASID. Fix the TCR_EL2 initialisation code to set PS and DS only when E2H=0, masking out HD, HA and A1 when E2H=1. Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Fixes: ad744e8cb346 ("arm64: Allow arm64_sw.hvhe on command line") Signed-off-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20250214133724.13179-1-will@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-17riscv: KVM: Fix SBI sleep_type useAndrew Jones1-1/+2
The spec says sleep_type is 32 bits wide and "In case the data is defined as 32bit wide, higher privilege software must ensure that it only uses 32 bit data." Mask off upper bits of sleep_type before using it. Fixes: 023c15151fbb ("RISC-V: KVM: Add SBI system suspend support") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250217084506.18763-12-ajones@ventanamicro.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-17riscv: KVM: Fix SBI TIME error generationAndrew Jones1-1/+1
When an invalid function ID of an SBI extension is used we should return not-supported, not invalid-param. Fixes: 5f862df5585c ("RISC-V: KVM: Add v0.1 replacement SBI extensions defined in v0.2") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250217084506.18763-11-ajones@ventanamicro.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-17riscv: KVM: Fix SBI IPI error generationAndrew Jones1-2/+11
When an invalid function ID of an SBI extension is used we should return not-supported, not invalid-param. Also, when we see that at least one hartid constructed from the base and mask parameters is invalid, then we should return invalid-param. Finally, rather than relying on overflowing a left shift to result in zero and then using that zero in a condition which [correctly] skips sending an IPI (but loops unnecessarily), explicitly check for overflow and exit the loop immediately. Fixes: 5f862df5585c ("RISC-V: KVM: Add v0.1 replacement SBI extensions defined in v0.2") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250217084506.18763-10-ajones@ventanamicro.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-17riscv: KVM: Fix hart suspend_type useAndrew Jones1-1/+2
The spec says suspend_type is 32 bits wide and "In case the data is defined as 32bit wide, higher privilege software must ensure that it only uses 32 bit data." Mask off upper bits of suspend_type before using it. Fixes: 763c8bed8c05 ("RISC-V: KVM: Implement SBI HSM suspend call") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250217084506.18763-9-ajones@ventanamicro.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-17riscv: KVM: Fix hart suspend status checkAndrew Jones1-4/+4
"Not stopped" means started or suspended so we need to check for a single state in order to have a chance to check for each state. Also, we need to use target_vcpu when checking for the suspend state. Fixes: 763c8bed8c05 ("RISC-V: KVM: Implement SBI HSM suspend call") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250217084506.18763-8-ajones@ventanamicro.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-02-16Linux 6.14-rc3Linus Torvalds1-1/+1
2025-02-15ring-buffer: Update pages_touched to reflect persistent buffer contentSteven Rostedt1-0/+5
The pages_touched field represents the number of subbuffers in the ring buffer that have content that can be read. This is used in accounting of "dirty_pages" and "buffer_percent" to allow the user to wait for the buffer to be filled to a certain amount before it reads the buffer in blocking mode. The persistent buffer never updated this value so it was set to zero, and this accounting would take it as it had no content. This would cause user space to wait for content even though there's enough content in the ring buffer that satisfies the buffer_percent. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250214123512.0631436e@gandalf.local.home Fixes: 5f3b6e839f3ce ("ring-buffer: Validate boot range memory events") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-15tracing: Do not allow mmap() of persistent ring bufferSteven Rostedt1-0/+4
When trying to mmap a trace instance buffer that is attached to reserve_mem, it would crash: BUG: unable to handle page fault for address: ffffe97bd00025c8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 2862f3067 P4D 2862f3067 PUD 0 Oops: Oops: 0000 [#1] PREEMPT_RT SMP PTI CPU: 4 UID: 0 PID: 981 Comm: mmap-rb Not tainted 6.14.0-rc2-test-00003-g7f1a5e3fbf9e-dirty #233 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:validate_page_before_insert+0x5/0xb0 Code: e2 01 89 d0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 <48> 8b 46 08 a8 01 75 67 66 90 48 89 f0 8b 50 34 85 d2 74 76 48 89 RSP: 0018:ffffb148c2f3f968 EFLAGS: 00010246 RAX: ffff9fa5d3322000 RBX: ffff9fa5ccff9c08 RCX: 00000000b879ed29 RDX: ffffe97bd00025c0 RSI: ffffe97bd00025c0 RDI: ffff9fa5ccff9c08 RBP: ffffb148c2f3f9f0 R08: 0000000000000004 R09: 0000000000000004 R10: 0000000000000000 R11: 0000000000000200 R12: 0000000000000000 R13: 00007f16a18d5000 R14: ffff9fa5c48db6a8 R15: 0000000000000000 FS: 00007f16a1b54740(0000) GS:ffff9fa73df00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffe97bd00025c8 CR3: 00000001048c6006 CR4: 0000000000172ef0 Call Trace: <TASK> ? __die_body.cold+0x19/0x1f ? __die+0x2e/0x40 ? page_fault_oops+0x157/0x2b0 ? search_module_extables+0x53/0x80 ? validate_page_before_insert+0x5/0xb0 ? kernelmode_fixup_or_oops.isra.0+0x5f/0x70 ? __bad_area_nosemaphore+0x16e/0x1b0 ? bad_area_nosemaphore+0x16/0x20 ? do_kern_addr_fault+0x77/0x90 ? exc_page_fault+0x22b/0x230 ? asm_exc_page_fault+0x2b/0x30 ? validate_page_before_insert+0x5/0xb0 ? vm_insert_pages+0x151/0x400 __rb_map_vma+0x21f/0x3f0 ring_buffer_map+0x21b/0x2f0 tracing_buffers_mmap+0x70/0xd0 __mmap_region+0x6f0/0xbd0 mmap_region+0x7f/0x130 do_mmap+0x475/0x610 vm_mmap_pgoff+0xf2/0x1d0 ksys_mmap_pgoff+0x166/0x200 __x64_sys_mmap+0x37/0x50 x64_sys_call+0x1670/0x1d70 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f The reason was that the code that maps the ring buffer pages to user space has: page = virt_to_page((void *)cpu_buffer->subbuf_ids[s]); And uses that in: vm_insert_pages(vma, vma->vm_start, pages, &nr_pages); But virt_to_page() does not work with vmap()'d memory which is what the persistent ring buffer has. It is rather trivial to allow this, but for now just disable mmap() of instances that have their ring buffer from the reserve_mem option. If an mmap() is performed on a persistent buffer it will return -ENODEV just like it would if the .mmap field wasn't defined in the file_operations structure. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250214115547.0d7287d3@gandalf.local.home Fixes: 9b7bdf6f6ece6 ("tracing: Have trace_printk not use binary prints if boot buffer") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-16modpost: Fix a few typos in a commentUwe Kleine-König1-2/+2
Namely: s/becasue/because/ and s/wiht/with/ plus an added article. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-02-16kbuild: userprogs: fix bitsize and target detection on clangThomas Weißschuh1-2/+2
scripts/Makefile.clang was changed in the linked commit to move --target from KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope. However that variable is not inspected by the userprogs logic, breaking cross compilation on clang. Use both variables to detect bitsize and target arguments for userprogs. Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-02-15tegra210-adma: fix 32-bit x86 buildLinus Torvalds1-3/+14
The Tegra210 Audio DMA controller driver did a plain divide: page_no = (res_page->start - res_base->start) / cdata->ch_base_offset; which causes problems on 32-bit x86 configurations that have 64-bit resource sizes: x86_64-linux-ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe': tegra210-adma.c:(.text+0x1322): undefined reference to `__udivdi3' because gcc doesn't generate the trivial code for a 64-by-32 divide, turning it into a function call to do a full 64-by-64 divide. And the kernel intentionally doesn't provide that helper function, because 99% of the time all you want is the narrower version. Of course, tegra210 is a 64-bit architecture and the 32-bit x86 build is purely for build testing, so this really is just about build coverage failure. But build coverage is good. Side note: div_u64() would be suboptimal if you actually have a 32-bit resource_t, so our "helper" for divides are admittedly making it harder than it should be to generate good code for all the possible cases. At some point, I'll consider 32-bit x86 so entirely legacy that I can't find it in myself to care any more, and we'll just add the __udivdi3 library function. But for now, the right thing to do is to use "div_u64()" to show that you know that you are doing the simpler divide with a 32-bit number. And the build error enforces that. While fixing the build issue, also check for division-by-zero, and for overflow. Which hopefully cannot happen on real production hardware, but the value of 'ch_base_offset' can definitely be zero in other places. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-02-15kbuild: fix linux-headers package build when $(CC) cannot link userspaceMasahiro Yamada1-2/+2
Since commit 5f73e7d0386d ("kbuild: refactor cross-compiling linux-headers package"), the linux-headers Debian package fails to build when $(CC) cannot build userspace applications, for example, when using toolchains installed by the 0day bot. The host programs in the linux-headers package should be rebuilt using the disto's cross-compiler, ${DEB_HOST_GNU_TYPE}-gcc instead of $(CC). Hence, the variable 'CC' must be expanded in this shell script instead of in the top-level Makefile. Commit f354fc88a72a ("kbuild: install-extmod-build: add missing quotation marks for CC variable") was not a correct fix because CC="ccache gcc" should be unrelated when rebuilding userspace tools. Fixes: 5f73e7d0386d ("kbuild: refactor cross-compiling linux-headers package") Reported-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com> Closes: https://lore.kernel.org/linux-kbuild/CAK7LNARb3xO3ptBWOMpwKcyf3=zkfhMey5H2KnB1dOmUwM79dA@mail.gmail.com/T/#t Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
2025-02-15tools: fix annoying "mkdir -p ..." logs when building tools in parallelMasahiro Yamada1-7/+2
When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds show awkward "mkdir -p ..." logs. $ make -j16 [ snip ] mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids Defining MAKEFLAGS=<value> on the command line wipes out command line switches from the resultant MAKEFLAGS definition, even though the command line switches are active. [1] MAKEFLAGS puts all single-letter options into the first word, and that word will be empty if no single-letter options were given. [2] However, this breaks if MAKEFLAGS=<value> is given on the command line. The tools/ and tools/% targets set MAKEFLAGS=<value> on the command line, which breaks the following code in tools/scripts/Makefile.include: short-opts := $(firstword -$(MAKEFLAGS)) If MAKEFLAGS really needs modification, it should be done through the environment variable, as follows: MAKEFLAGS=<value> $(MAKE) ... That said, I question whether modifying MAKEFLAGS is necessary here. The only flag we might want to exclude is --no-print-directory, as the tools build system changes the working directory. However, people might find the "Entering/Leaving directory" logs annoying. I simply removed the offending MAKEFLAGS=<value>. [1]: https://savannah.gnu.org/bugs/?62469 [2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags Fixes: ea01fa9f63ae ("tools: Connect to the kernel build system") Fixes: a50e43332756 ("perf tools: Honor parallel jobs") Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Daniel Xu <dxu@dxuuu.xyz>
2025-02-14x86/sev: Fix broken SNP support with KVM module built-inAshish Kalra3-20/+39
Fix issues with enabling SNP host support and effectively SNP support which is broken with respect to the KVM module being built-in. SNP host support is enabled in snp_rmptable_init() which is invoked as device_initcall(). SNP check on IOMMU is done during IOMMU PCI init (IOMMU_PCI_INIT stage). And for that reason snp_rmptable_init() is currently invoked via device_initcall() and cannot be invoked via subsys_initcall() as core IOMMU subsystem gets initialized via subsys_initcall(). Now, if kvm_amd module is built-in, it gets initialized before SNP host support is enabled in snp_rmptable_init() : [ 10.131811] kvm_amd: TSC scaling supported [ 10.136384] kvm_amd: Nested Virtualization enabled [ 10.141734] kvm_amd: Nested Paging enabled [ 10.146304] kvm_amd: LBR virtualization supported [ 10.151557] kvm_amd: SEV enabled (ASIDs 100 - 509) [ 10.156905] kvm_amd: SEV-ES enabled (ASIDs 1 - 99) [ 10.162256] kvm_amd: SEV-SNP enabled (ASIDs 1 - 99) [ 10.171508] kvm_amd: Virtual VMLOAD VMSAVE supported [ 10.177052] kvm_amd: Virtual GIF supported ... ... [ 10.201648] kvm_amd: in svm_enable_virtualization_cpu And then svm_x86_ops->enable_virtualization_cpu() (svm_enable_virtualization_cpu) programs MSR_VM_HSAVE_PA as following: wrmsrl(MSR_VM_HSAVE_PA, sd->save_area_pa); So VM_HSAVE_PA is non-zero before SNP support is enabled on all CPUs. snp_rmptable_init() gets invoked after svm_enable_virtualization_cpu() as following : ... [ 11.256138] kvm_amd: in svm_enable_virtualization_cpu ... [ 11.264918] SEV-SNP: in snp_rmptable_init This triggers a #GP exception in snp_rmptable_init() when snp_enable() is invoked to set SNP_EN in SYSCFG MSR: [ 11.294289] unchecked MSR access error: WRMSR to 0xc0010010 (tried to write 0x0000000003fc0000) at rIP: 0xffffffffaf5d5c28 (native_write_msr+0x8/0x30) ... [ 11.294404] Call Trace: [ 11.294482] <IRQ> [ 11.294513] ? show_stack_regs+0x26/0x30 [ 11.294522] ? ex_handler_msr+0x10f/0x180 [ 11.294529] ? search_extable+0x2b/0x40 [ 11.294538] ? fixup_exception+0x2dd/0x340 [ 11.294542] ? exc_general_protection+0x14f/0x440 [ 11.294550] ? asm_exc_general_protection+0x2b/0x30 [ 11.294557] ? __pfx_snp_enable+0x10/0x10 [ 11.294567] ? native_write_msr+0x8/0x30 [ 11.294570] ? __snp_enable+0x5d/0x70 [ 11.294575] snp_enable+0x19/0x20 [ 11.294578] __flush_smp_call_function_queue+0x9c/0x3a0 [ 11.294586] generic_smp_call_function_single_interrupt+0x17/0x20 [ 11.294589] __sysvec_call_function+0x20/0x90 [ 11.294596] sysvec_call_function+0x80/0xb0 [ 11.294601] </IRQ> [ 11.294603] <TASK> [ 11.294605] asm_sysvec_call_function+0x1f/0x30 ... [ 11.294631] arch_cpu_idle+0xd/0x20 [ 11.294633] default_idle_call+0x34/0xd0 [ 11.294636] do_idle+0x1f1/0x230 [ 11.294643] ? complete+0x71/0x80 [ 11.294649] cpu_startup_entry+0x30/0x40 [ 11.294652] start_secondary+0x12d/0x160 [ 11.294655] common_startup_64+0x13e/0x141 [ 11.294662] </TASK> This #GP exception is getting triggered due to the following errata for AMD family 19h Models 10h-1Fh Processors: Processor may generate spurious #GP(0) Exception on WRMSR instruction: Description: The Processor will generate a spurious #GP(0) Exception on a WRMSR instruction if the following conditions are all met: - the target of the WRMSR is a SYSCFG register. - the write changes the value of SYSCFG.SNPEn from 0 to 1. - One of the threads that share the physical core has a non-zero value in the VM_HSAVE_PA MSR. The document being referred to above: https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/revision-guides/57095-PUB_1_01.pdf To summarize, with kvm_amd module being built-in, KVM/SVM initialization happens before host SNP is enabled and this SVM initialization sets VM_HSAVE_PA to non-zero, which then triggers a #GP when SYSCFG.SNPEn is being set and this will subsequently cause SNP_INIT(_EX) to fail with INVALID_CONFIG error as SYSCFG[SnpEn] is not set on all CPUs. Essentially SNP host enabling code should be invoked before KVM initialization, which is currently not the case when KVM is built-in. Add fix to call snp_rmptable_init() early from iommu_snp_enable() directly and not invoked via device_initcall() which enables SNP host support before KVM initialization with kvm_amd module built-in. Add additional handling for `iommu=off` or `amd_iommu=off` options. Note that IOMMUs need to be enabled for SNP initialization, therefore, if host SNP support is enabled but late IOMMU initialization fails then that will cause PSP driver's SNP_INIT to fail as IOMMU SNP sanity checks in SNP firmware will fail with invalid configuration error as below: [ 9.723114] ccp 0000:23:00.1: sev enabled [ 9.727602] ccp 0000:23:00.1: psp enabled [ 9.732527] ccp 0000:a2:00.1: enabling device (0000 -> 0002) [ 9.739098] ccp 0000:a2:00.1: no command queues available [ 9.745167] ccp 0000:a2:00.1: psp enabled [ 9.805337] ccp 0000:23:00.1: SEV-SNP: failed to INIT rc -5, error 0x3 [ 9.866426] ccp 0000:23:00.1: SEV API:1.53 build:5 Fixes: c3b86e61b756 ("x86/cpufeatures: Enable/unmask SEV-SNP CPU feature") Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Vasant Hegde <vasant.hegde@amd.com> Signed-off-by: Vasant Hegde <vasant.hegde@amd.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Acked-by: Joerg Roedel <jroedel@suse.de> Message-ID: <138b520fb83964782303b43ade4369cd181fdd9c.1739226950.git.ashish.kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-14KVM: SVM: Ensure PSP module is initialized if KVM module is built-inSean Christopherson1-0/+10
The kernel's initcall infrastructure lacks the ability to express dependencies between initcalls, whereas the modules infrastructure automatically handles dependencies via symbol loading. Ensure the PSP SEV driver is initialized before proceeding in sev_hardware_setup() if KVM is built-in as the dependency isn't handled by the initcall infrastructure. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Message-ID: <f78ddb64087df27e7bcb1ae0ab53f55aa0804fab.1739226950.git.ashish.kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-14crypto: ccp: Add external API interface for PSP module initializationSean Christopherson2-0/+23
KVM is dependent on the PSP SEV driver and PSP SEV driver needs to be loaded before KVM module. In case of module loading any dependent modules are automatically loaded but in case of built-in modules there is no inherent mechanism available to specify dependencies between modules and ensure that any dependent modules are loaded implicitly. Add a new external API interface for PSP module initialization which allows PSP SEV driver to be loaded explicitly if KVM is built-in. Signed-off-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Ashish Kalra <ashish.kalra@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Message-ID: <15279ca0cad56a07cf12834ec544310f85ff5edc.1739226950.git.ashish.kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-14alpha: Use str_yes_no() helper in pci_dac_dma_supported()Thorsten Blum1-1/+2
Remove hard-coded strings by using the str_yes_no() helper function. Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Signed-off-by: Matt Turner <mattst88@gmail.com>
2025-02-14alpha: Replace one-element array with flexible array memberThorsten Blum1-1/+1
Replace the deprecated one-element array with a modern flexible array member in the struct crb_struct. Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Signed-off-by: Matt Turner <mattst88@gmail.com>
2025-02-14alpha: align stack for page fault and user unaligned trap handlersIvan Kokshaysky3-13/+13
do_page_fault() and do_entUna() are special because they use non-standard stack frame layout. Fix them manually. Cc: stable@vger.kernel.org Tested-by: Maciej W. Rozycki <macro@orcam.me.uk> Tested-by: Magnus Lindholm <linmag7@gmail.com> Tested-by: Matt Turner <mattst88@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Ivan Kokshaysky <ink@unseen.parts> Signed-off-by: Matt Turner <mattst88@gmail.com>
2025-02-14alpha: make stack 16-byte aligned (most cases)Ivan Kokshaysky1-0/+2
The problem is that GCC expects 16-byte alignment of the incoming stack since early 2004, as Maciej found out [1]: Having actually dug speculatively I can see that the psABI was changed in GCC 3.5 with commit e5e10fb4a350 ("re PR target/14539 (128-bit long double improperly aligned)") back in Mar 2004, when the stack pointer alignment was increased from 8 bytes to 16 bytes, and arch/alpha/kernel/entry.S has various suspicious stack pointer adjustments, starting with SP_OFF which is not a whole multiple of 16. Also, as Magnus noted, "ALPHA Calling Standard" [2] required the same: D.3.1 Stack Alignment This standard requires that stacks be octaword aligned at the time a new procedure is invoked. However: - the "normal" kernel stack is always misaligned by 8 bytes, thanks to the odd number of 64-bit words in 'struct pt_regs', which is the very first thing pushed onto the kernel thread stack; - syscall, fault, interrupt etc. handlers may, or may not, receive aligned stack depending on numerous factors. Somehow we got away with it until recently, when we ended up with a stack corruption in kernel/smp.c:smp_call_function_single() due to its use of 32-byte aligned local data and the compiler doing clever things allocating it on the stack. This adds padding between the PAL-saved and kernel-saved registers so that 'struct pt_regs' have an even number of 64-bit words. This makes the stack properly aligned for most of the kernel code, except two handlers which need special threatment. Note: struct pt_regs doesn't belong in uapi/asm; this should be fixed, but let's put this off until later. Link: https://lore.kernel.org/rcu/alpine.DEB.2.21.2501130248010.18889@angie.orcam.me.uk/ [1] Link: https://bitsavers.org/pdf/dec/alpha/Alpha_Calling_Standard_Rev_2.0_19900427.pdf [2] Cc: stable@vger.kernel.org Tested-by: Maciej W. Rozycki <macro@orcam.me.uk> Tested-by: Magnus Lindholm <linmag7@gmail.com> Tested-by: Matt Turner <mattst88@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Ivan Kokshaysky <ink@unseen.parts> Signed-off-by: Matt Turner <mattst88@gmail.com>
2025-02-14alpha: replace hardcoded stack offsets with autogenerated onesIvan Kokshaysky2-4/+4
This allows the assembly in entry.S to automatically keep in sync with changes in the stack layout (struct pt_regs and struct switch_stack). Cc: stable@vger.kernel.org Tested-by: Maciej W. Rozycki <macro@orcam.me.uk> Tested-by: Matt Turner <mattst88@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Ivan Kokshaysky <ink@unseen.parts> Signed-off-by: Matt Turner <mattst88@gmail.com>
2025-02-14ring-buffer: Validate the persistent meta data subbuf arraySteven Rostedt1-2/+20
The meta data for a mapped ring buffer contains an array of indexes of all the subbuffers. The first entry is the reader page, and the rest of the entries lay out the order of the subbuffers in how the ring buffer link list is to be created. The validator currently makes sure that all the entries are within the range of 0 and nr_subbufs. But it does not check if there are any duplicates. While working on the ring buffer, I corrupted this array, where I added duplicates. The validator did not catch it and created the ring buffer link list on top of it. Luckily, the corruption was only that the reader page was also in the writer path and only presented corrupted data but did not crash the kernel. But if there were duplicates in the writer side, then it could corrupt the ring buffer link list and cause a crash. Create a bitmask array with the size of the number of subbuffers. Then clear it. When walking through the subbuf array checking to see if the entries are within the range, test if its bit is already set in the subbuf_mask. If it is, then there is duplicates and fail the validation. If not, set the corresponding bit and continue. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250214102820.7509ddea@gandalf.local.home Fixes: c76883f18e59b ("ring-buffer: Add test if range of boot buffer is valid") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-14tracing: Have the error of __tracing_resize_ring_buffer() passed to userSteven Rostedt1-7/+1
Currently if __tracing_resize_ring_buffer() returns an error, the tracing_resize_ringbuffer() returns -ENOMEM. But it may not be a memory issue that caused the function to fail. If the ring buffer is memory mapped, then the resizing of the ring buffer will be disabled. But if the user tries to resize the buffer, it will get an -ENOMEM returned, which is confusing because there is plenty of memory. The actual error returned was -EBUSY, which would make much more sense to the user. Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250213134132.7e4505d7@gandalf.local.home Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-02-14ring-buffer: Unlock resize on mmap errorSteven Rostedt1-0/+1
Memory mapping the tracing ring buffer will disable resizing the buffer. But if there's an error in the memory mapping like an invalid parameter, the function exits out without re-enabling the resizing of the ring buffer, preventing the ring buffer from being resized after that. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Link: https://lore.kernel.org/20250213131957.530ec3c5@gandalf.local.home Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-02-14partitions: mac: fix handling of bogus partition tableJann Horn1-3/+15
Fix several issues in partition probing: - The bailout for a bad partoffset must use put_dev_sector(), since the preceding read_part_sector() succeeded. - If the partition table claims a silly sector size like 0xfff bytes (which results in partition table entries straddling sector boundaries), bail out instead of accessing out-of-bounds memory. - We must not assume that the partition table contains proper NUL termination - use strnlen() and strncmp() instead of strlen() and strcmp(). Cc: stable@vger.kernel.org Signed-off-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/r/20250214-partition-mac-v1-1-c1c626dffbd5@google.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-14serial: 8250: Fix fifo underflow on flushJohn Keeping3-0/+27
When flushing the serial port's buffer, uart_flush_buffer() calls kfifo_reset() but if there is an outstanding DMA transfer then the completion function will consume data from the kfifo via uart_xmit_advance(), underflowing and leading to ongoing DMA as the driver tries to transmit another 2^32 bytes. This is readily reproduced with serial-generic and amidi sending even short messages as closing the device on exit will wait for the fifo to drain and in the underflow case amidi hangs for 30 seconds on exit in tty_wait_until_sent(). A trace of that gives: kworker/1:1-84 [001] 51.769423: bprint: serial8250_tx_dma: tx_size=3 fifo_len=3 amidi-763 [001] 51.769460: bprint: uart_flush_buffer: resetting fifo irq/21-fe530000-76 [000] 51.769474: bprint: __dma_tx_complete: tx_size=3 irq/21-fe530000-76 [000] 51.769479: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294967293 irq/21-fe530000-76 [000] 51.781295: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.781301: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294963197 irq/21-fe530000-76 [000] 51.793131: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.793135: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294959101 irq/21-fe530000-76 [000] 51.804949: bprint: __dma_tx_complete: tx_size=4096 Since the port lock is held in when the kfifo is reset in uart_flush_buffer() and in __dma_tx_complete(), adding a flush_buffer hook to adjust the outstanding DMA byte count is sufficient to avoid the kfifo underflow. Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Cc: stable <stable@kernel.org> Signed-off-by: John Keeping <jkeeping@inmusicbrands.com> Link: https://lore.kernel.org/r/20250208124148.1189191-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.