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2023-08-04KVM: nSVM: Skip writes to MSR_AMD64_TSC_RATIO if guest state isn't loadedSean Christopherson1-1/+2
Skip writes to MSR_AMD64_TSC_RATIO that are done in the context of a vCPU if guest state isn't loaded, i.e. if KVM will update MSR_AMD64_TSC_RATIO during svm_prepare_switch_to_guest() before entering the guest. Checking guest_state_loaded may or may not be a net positive for performance as the current_tsc_ratio cache will optimize away duplicate WRMSRs in the vast majority of scenarios. However, the cost of the check is negligible, and the real motivation is to document that KVM needs to load the vCPU's value only when running the vCPU. Link: https://lore.kernel.org/r/20230729011608.1065019-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: x86: Always write vCPU's current TSC offset/ratio in vendor hooksSean Christopherson6-16/+15
Drop the @offset and @multiplier params from the kvm_x86_ops hooks for propagating TSC offsets/multipliers into hardware, and instead have the vendor implementations pull the information directly from the vCPU structure. The respective vCPU fields _must_ be written at the same time in order to maintain consistent state, i.e. it's not random luck that the value passed in by all callers is grabbed from the vCPU. Explicitly grabbing the value from the vCPU field in SVM's implementation in particular will allow for additional cleanup without introducing even more subtle dependencies. Specifically, SVM can skip the WRMSR if guest state isn't loaded, i.e. svm_prepare_switch_to_guest() will load the correct value for the vCPU prior to entering the guest. This also reconciles KVM's handling of related values that are stored in the vCPU, as svm_write_tsc_offset() already assumes/requires the caller to have updated l1_tsc_offset. Link: https://lore.kernel.org/r/20230729011608.1065019-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: SVM: Clean up preemption toggling related to MSR_AMD64_TSC_RATIOSean Christopherson1-5/+3
Explicitly disable preemption when writing MSR_AMD64_TSC_RATIO only in the "outer" helper, as all direct callers of the "inner" helper now run with preemption already disabled. And that isn't a coincidence, as the outer helper requires a vCPU and is intended to be used when modifying guest state and/or emulating guest instructions, which are typically done with preemption enabled. Direct use of the inner helper should be extremely limited, as the only time KVM should modify MSR_AMD64_TSC_RATIO without a vCPU is when sanitizing the MSR for a specific pCPU (currently done when {en,dis}abling disabling SVM). The other direct caller is svm_prepare_switch_to_guest(), which does have a vCPU, but is a one-off special case: KVM is about to enter the guest on a specific pCPU and thus must have preemption disabled. Link: https://lore.kernel.org/r/20230729011608.1065019-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: nSVM: Use the "outer" helper for writing multiplier to MSR_AMD64_TSC_RATIOSean Christopherson3-6/+5
When emulating nested SVM transitions, use the outer helper for writing the TSC multiplier for L2. Using the inner helper only for one-off cases, i.e. for paths where KVM is NOT emulating or modifying vCPU state, will allow for multiple cleanups: - Explicitly disabling preemption only in the outer helper - Getting the multiplier from the vCPU field in the outer helper - Skipping the WRMSR in the outer helper if guest state isn't loaded Opportunistically delete an extra newline. No functional change intended. Link: https://lore.kernel.org/r/20230729011608.1065019-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: nSVM: Load L1's TSC multiplier based on L1 state, not L2 stateSean Christopherson1-2/+2
When emulating nested VM-Exit, load L1's TSC multiplier if L1's desired ratio doesn't match the current ratio, not if the ratio L1 is using for L2 diverges from the default. Functionally, the end result is the same as KVM will run L2 with L1's multiplier if L2's multiplier is the default, i.e. checking that L1's multiplier is loaded is equivalent to checking if L2 has a non-default multiplier. However, the assertion that TSC scaling is exposed to L1 is flawed, as userspace can trigger the WARN at will by writing the MSR and then updating guest CPUID to hide the feature (modifying guest CPUID is allowed anytime before KVM_RUN). E.g. hacking KVM's state_test selftest to do vcpu_set_msr(vcpu, MSR_AMD64_TSC_RATIO, 0); vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_TSCRATEMSR); after restoring state in a new VM+vCPU yields an endless supply of: ------------[ cut here ]------------ WARNING: CPU: 10 PID: 206939 at arch/x86/kvm/svm/nested.c:1105 nested_svm_vmexit+0x6af/0x720 [kvm_amd] Call Trace: nested_svm_exit_handled+0x102/0x1f0 [kvm_amd] svm_handle_exit+0xb9/0x180 [kvm_amd] kvm_arch_vcpu_ioctl_run+0x1eab/0x2570 [kvm] kvm_vcpu_ioctl+0x4c9/0x5b0 [kvm] ? trace_hardirqs_off+0x4d/0xa0 __se_sys_ioctl+0x7a/0xc0 __x64_sys_ioctl+0x21/0x30 do_syscall_64+0x41/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Unlike the nested VMRUN path, hoisting the svm->tsc_scaling_enabled check into the if-statement is wrong as KVM needs to ensure L1's multiplier is loaded in the above scenario. Alternatively, the WARN_ON() could simply be deleted, but that would make KVM's behavior even more subtle, e.g. it's not immediately obvious why it's safe to write MSR_AMD64_TSC_RATIO when checking only tsc_ratio_msr. Fixes: 5228eb96a487 ("KVM: x86: nSVM: implement nested TSC scaling") Cc: Maxim Levitsky <mlevitsk@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230729011608.1065019-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: nSVM: Check instead of asserting on nested TSC scaling supportSean Christopherson1-3/+2
Check for nested TSC scaling support on nested SVM VMRUN instead of asserting that TSC scaling is exposed to L1 if L1's MSR_AMD64_TSC_RATIO has diverged from KVM's default. Userspace can trigger the WARN at will by writing the MSR and then updating guest CPUID to hide the feature (modifying guest CPUID is allowed anytime before KVM_RUN). E.g. hacking KVM's state_test selftest to do vcpu_set_msr(vcpu, MSR_AMD64_TSC_RATIO, 0); vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_TSCRATEMSR); after restoring state in a new VM+vCPU yields an endless supply of: ------------[ cut here ]------------ WARNING: CPU: 164 PID: 62565 at arch/x86/kvm/svm/nested.c:699 nested_vmcb02_prepare_control+0x3d6/0x3f0 [kvm_amd] Call Trace: <TASK> enter_svm_guest_mode+0x114/0x560 [kvm_amd] nested_svm_vmrun+0x260/0x330 [kvm_amd] vmrun_interception+0x29/0x30 [kvm_amd] svm_invoke_exit_handler+0x35/0x100 [kvm_amd] svm_handle_exit+0xe7/0x180 [kvm_amd] kvm_arch_vcpu_ioctl_run+0x1eab/0x2570 [kvm] kvm_vcpu_ioctl+0x4c9/0x5b0 [kvm] __se_sys_ioctl+0x7a/0xc0 __x64_sys_ioctl+0x21/0x30 do_syscall_64+0x41/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x45ca1b Note, the nested #VMEXIT path has the same flaw, but needs a different fix and will be handled separately. Fixes: 5228eb96a487 ("KVM: x86: nSVM: implement nested TSC scaling") Cc: Maxim Levitsky <mlevitsk@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230729011608.1065019-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: x86: Advertise AMX-COMPLEX CPUID to userspaceTao Su2-1/+3
Latest Intel platform GraniteRapids-D introduces AMX-COMPLEX, which adds two instructions to perform matrix multiplication of two tiles containing complex elements and accumulate the results into a packed single precision tile. AMX-COMPLEX is enumerated via CPUID.(EAX=7,ECX=1):EDX[bit 8] Advertise AMX_COMPLEX if it's supported in hardware. There are no VMX controls for the feature, i.e. the instructions can't be interecepted, and KVM advertises base AMX in CPUID if AMX is supported in hardware, even if KVM doesn't advertise AMX as being supported in XCR0, e.g. because the process didn't opt-in to allocating tile data. Signed-off-by: Tao Su <tao1.su@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20230802022954.193843-1-tao1.su@linux.intel.com [sean: tweak last paragraph of changelog] Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: VMX: Skip VMCLEAR logic during emergency reboots if CR4.VMXE=0Sean Christopherson1-2/+10
Bail from vmx_emergency_disable() without processing the list of loaded VMCSes if CR4.VMXE=0, i.e. if the CPU can't be post-VMXON. It should be impossible for the list to have entries if VMX is already disabled, and even if that invariant doesn't hold, VMCLEAR will #UD anyways, i.e. processing the list is pointless even if it somehow isn't empty. Assuming no existing KVM bugs, this should be a glorified nop. The primary motivation for the change is to avoid having code that looks like it does VMCLEAR, but then skips VMXON, which is nonsensical. Suggested-by: Kai Huang <kai.huang@intel.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-20-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: SVM: Use "standard" stgi() helper when disabling SVMSean Christopherson1-10/+3
Now that kvm_rebooting is guaranteed to be true prior to disabling SVM in an emergency, use the existing stgi() helper instead of open coding STGI. In effect, eat faults on STGI if and only if kvm_rebooting==true. Link: https://lore.kernel.org/r/20230721201859.2307736-19-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: x86: Force kvm_rebooting=true during emergency reboot/crashSean Christopherson2-0/+4
Set kvm_rebooting when virtualization is disabled in an emergency so that KVM eats faults on virtualization instructions even if kvm_reboot() isn't reached. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-18-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/virt: KVM: Move "disable SVM" helper into KVM SVMSean Christopherson2-54/+25
Move cpu_svm_disable() into KVM proper now that all hardware virtualization management is routed through KVM. Remove the now-empty virtext.h. No functional change intended. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-17-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: VMX: Ensure CPU is stable when probing basic VMX supportSean Christopherson1-3/+14
Disable migration when probing VMX support during module load to ensure the CPU is stable, mostly to match similar SVM logic, where allowing migration effective requires deliberately writing buggy code. As a bonus, KVM won't report the wrong CPU to userspace if VMX is unsupported, but in practice that is a very, very minor bonus as the only way that reporting the wrong CPU would actually matter is if hardware is broken or if the system is misconfigured, i.e. if KVM gets migrated from a CPU that _does_ support VMX to a CPU that does _not_ support VMX. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-16-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: SVM: Check that the current CPU supports SVM in kvm_is_svm_supported()Sean Christopherson1-6/+19
Check "this" CPU instead of the boot CPU when querying SVM support so that the per-CPU checks done during hardware enabling actually function as intended, i.e. will detect issues where SVM isn't support on all CPUs. Disable migration for the use from svm_init() mostly so that the standard accessors for the per-CPU data can be used without getting yelled at by CONFIG_DEBUG_PREEMPT=y sanity checks. Preventing the "disabled by BIOS" error message from reporting the wrong CPU is largely a bonus, as ensuring a stable CPU during module load is a non-goal for KVM. Link: https://lore.kernel.org/all/ZAdxNgv0M6P63odE@google.com Cc: Kai Huang <kai.huang@intel.com> Cc: Chao Gao <chao.gao@intel.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-15-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/virt: KVM: Open code cpu_has_svm() into kvm_is_svm_supported()Sean Christopherson2-31/+8
Fold the guts of cpu_has_svm() into kvm_is_svm_supported(), its sole remaining user. No functional change intended. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-14-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/virt: Drop unnecessary check on extended CPUID level in cpu_has_svm()Sean Christopherson1-6/+0
Drop the explicit check on the extended CPUID level in cpu_has_svm(), the kernel's cached CPUID info will leave the entire SVM leaf unset if said leaf is not supported by hardware. Prior to using cached information, the check was needed to avoid false positives due to Intel's rather crazy CPUID behavior of returning the values of the maximum supported leaf if the specified leaf is unsupported. Fixes: 682a8108872f ("x86/kvm/svm: Simplify cpu_has_svm()") Link: https://lore.kernel.org/r/20230721201859.2307736-13-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04KVM: SVM: Make KVM_AMD depend on CPU_SUP_AMD or CPU_SUP_HYGONSean Christopherson1-1/+1
Make building KVM SVM support depend on support for AMD or Hygon. KVM already effectively restricts SVM support to AMD and Hygon by virtue of the vendor string checks in cpu_has_svm(), and KVM VMX supports depends on one of its three known vendors (Intel, Centaur, or Zhaoxin). Add the CPU_SUP_HYGON clause even though CPU_SUP_HYGON selects CPU_SUP_AMD to document that KVM SVM support isn't just for AMD CPUs, and to prevent breakage should Hygon support ever become a standalone thing. Link: https://lore.kernel.org/r/20230721201859.2307736-12-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/virt: KVM: Move VMXOFF helpers into KVM VMXSean Christopherson2-45/+26
Now that VMX is disabled in emergencies via the virt callbacks, move the VMXOFF helpers into KVM, the only remaining user. No functional change intended. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-11-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/virt: KVM: Open code cpu_has_vmx() in KVM VMXSean Christopherson2-11/+1
Fold the raw CPUID check for VMX into kvm_is_vmx_supported(), its sole user. Keep the check even though KVM also checks X86_FEATURE_VMX, as the intent is to provide a unique error message if VMX is unsupported by hardware, whereas X86_FEATURE_VMX may be clear due to firmware and/or kernel actions. No functional change intended. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-10-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: Expose VMCS crash hooks if and only if KVM_{INTEL,AMD} is enabledSean Christopherson2-1/+8
Expose the crash/reboot hooks used by KVM to disable virtualization in hardware and unblock INIT only if there's a potential in-tree user, i.e. either KVM_INTEL or KVM_AMD is enabled. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: Disable virtualization during reboot iff callback is registeredSean Christopherson1-2/+1
Attempt to disable virtualization during an emergency reboot if and only if there is a registered virt callback, i.e. iff a hypervisor (KVM) is active. If there's no active hypervisor, then the CPU can't be operating with VMX or SVM enabled (barring an egregious bug). Checking for a valid callback instead of simply for SVM or VMX support can also eliminates spurious NMIs by avoiding the unecessary call to nmi_shootdown_cpus_on_restart(). Note, IRQs are disabled, which prevents KVM from coming along and enabling virtualization after the fact. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: Hoist "disable virt" helpers above "emergency reboot" pathSean Christopherson1-45/+45
Move the various "disable virtualization" helpers above the emergency reboot path so that emergency_reboot_disable_virtualization() can be stubbed out in a future patch if neither KVM_INTEL nor KVM_AMD is enabled, i.e. if there is no in-tree user of CPU virtualization. No functional change intended. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: Assert that IRQs are disabled when turning off virtualizationSean Christopherson1-1/+7
Assert that IRQs are disabled when turning off virtualization in an emergency. KVM enables hardware via on_each_cpu(), i.e. could re-enable hardware if a pending IPI were delivered after disabling virtualization. Remove a misleading comment from emergency_reboot_disable_virtualization() about "just" needing to guarantee the CPU is stable (see above). Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: KVM: Disable SVM during reboot via virt/KVM reboot callbackSean Christopherson3-13/+17
Use the virt callback to disable SVM (and set GIF=1) during an emergency instead of blindly attempting to disable SVM. Like the VMX case, if a hypervisor, i.e. KVM, isn't loaded/active, SVM can't be in use. Acked-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: KVM: Handle VMXOFF in KVM's reboot callbackSean Christopherson3-33/+14
Use KVM VMX's reboot/crash callback to do VMXOFF in an emergency instead of manually and blindly doing VMXOFF. There's no need to attempt VMXOFF if a hypervisor, i.e. KVM, isn't loaded/active, i.e. if the CPU can't possibly be post-VMXON. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: Harden virtualization hooks for emergency rebootSean Christopherson3-12/+29
Provide dedicated helpers to (un)register virt hooks used during an emergency crash/reboot, and WARN if there is an attempt to overwrite the registered callback, or an attempt to do an unpaired unregister. Opportunsitically use rcu_assign_pointer() instead of RCU_INIT_POINTER(), mainly so that the set/unset paths are more symmetrical, but also because any performance gains from using RCU_INIT_POINTER() are meaningless for this code. Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20230721201859.2307736-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-04x86/reboot: VMCLEAR active VMCSes before emergency rebootSean Christopherson5-40/+27
VMCLEAR active VMCSes before any emergency reboot, not just if the kernel may kexec into a new kernel after a crash. Per Intel's SDM, the VMX architecture doesn't require the CPU to flush the VMCS cache on INIT. If an emergency reboot doesn't RESET CPUs, cached VMCSes could theoretically be kept and only be written back to memory after the new kernel is booted, i.e. could effectively corrupt memory after reboot. Opportunistically remove the setting of the global pointer to NULL to make checkpatch happy. Cc: Andrew Cooper <Andrew.Cooper3@citrix.com> Link: https://lore.kernel.org/r/20230721201859.2307736-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-03KVM: x86: Retry APIC optimized map recalc if vCPU is added/enabledSean Christopherson1-4/+25
Retry the optimized APIC map recalculation if an APIC-enabled vCPU shows up between allocating the map and filling in the map data. Conditionally reschedule before retrying even though the number of vCPUs that can be created is bounded by KVM. Retrying a few thousand times isn't so slow as to be hugely problematic, but it's not blazing fast either. Reset xapic_id_mistach on each retry as a vCPU could change its xAPIC ID between loops, but do NOT reset max_id. The map size also factors in whether or not a vCPU's local APIC is hardware-enabled, i.e. userspace and/or the guest can theoretically keep KVM retrying indefinitely. The only downside is that KVM will allocate more memory than is strictly necessary if the vCPU with the highest x2APIC ID disabled its APIC while the recalculation was in-progress. Refresh kvm->arch.apic_map_dirty to opportunistically change it from DIRTY => UPDATE_IN_PROGRESS to avoid an unnecessary recalc from a different task, i.e. if another task is waiting to attempt an update (which is likely since a retry happens if and only if an update is required). Link: https://lore.kernel.org/r/20230602233250.1014316-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-03KVM: VMX: Drop unnecessary vmx_fb_clear_ctrl_available "cache"Sean Christopherson1-14/+3
Now that KVM snapshots the host's MSR_IA32_ARCH_CAPABILITIES, drop the similar snapshot/cache of whether or not KVM is allowed to manipulate MSR_IA32_MCU_OPT_CTRL.FB_CLEAR_DIS. The motivation for the cache was presumably to avoid the RDMSR, e.g. boot_cpu_has_bug() is quite cheap, and modifying the vCPU's MSR_IA32_ARCH_CAPABILITIES is an infrequent option and a relatively slow path. Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20230607004311.1420507-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-03KVM: x86: Snapshot host's MSR_IA32_ARCH_CAPABILITIESSean Christopherson3-22/+14
Snapshot the host's MSR_IA32_ARCH_CAPABILITIES, if it's supported, instead of reading the MSR every time KVM wants to query the host state, e.g. when initializing the default value during vCPU creation. The paths that query ARCH_CAPABILITIES aren't particularly performance sensitive, but creating vCPUs is a frequent enough operation that burning 8 bytes is a good trade-off. Alternatively, KVM could add a field in kvm_caps and thus skip the on-demand calculations entirely, but a pure snapshot isn't possible due to the way KVM handles the l1tf_vmx_mitigation module param. And unlike the other "supported" fields in kvm_caps, KVM doesn't enforce the "supported" value, i.e. KVM treats ARCH_CAPABILITIES like a CPUID leaf and lets userspace advertise whatever it wants. Those problems are solvable, but it's not clear there is real benefit versus snapshotting the host value, and grabbing the host value will allow additional cleanup of KVM's FB_CLEAR_CTRL code. Link: https://lore.kernel.org/all/20230524061634.54141-2-chao.gao@intel.com Cc: Chao Gao <chao.gao@intel.com> Cc: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20230607004311.1420507-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-03KVM: x86: Advertise host CPUID 0x80000005 in KVM_GET_SUPPORTED_CPUIDTakahiro Itazuri1-0/+3
Advertise CPUID 0x80000005 (L1 cache and TLB info) to userspace so that VMMs that reflect KVM_GET_SUPPORTED_CPUID into KVM_SET_CPUID2 will enumerate sane cache/TLB information to the guest. CPUID 0x80000006 (L2 cache and TLB and L3 cache info) has been returned since commit 43d05de2bee7 ("KVM: pass through CPUID(0x80000006)"). Enumerating both 0x80000005 and 0x80000006 with KVM_GET_SUPPORTED_CPUID is better than reporting one or the other, and 0x80000005 could be helpful for VMM to pass it to KVM_SET_CPUID{,2} for the same reason with 0x80000006. Signed-off-by: Takahiro Itazuri <itazur@amazon.com> Link: https://lore.kernel.org/all/ZK7NmfKI9xur%2FMop@google.com Link: https://lore.kernel.org/r/20230712183136.85561-1-itazur@amazon.com [sean: add link, massage changelog] Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-08-03KVM: x86: Remove x86_emulate_ops::guest_has_long_modeMichal Luczaj2-7/+0
Remove x86_emulate_ops::guest_has_long_mode along with its implementation, emulator_guest_has_long_mode(). It has been unused since commit 1d0da94cdafe ("KVM: x86: do not go through ctxt->ops when emulating rsm"). No functional change intended. Signed-off-by: Michal Luczaj <mhal@rbox.co> Link: https://lore.kernel.org/r/20230718101809.1249769-1-mhal@rbox.co Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-07-31KVM: x86: Use sysfs_emit() instead of sprintf()Like Xu2-3/+3
Use sysfs_emit() instead of the sprintf() for sysfs entries. sysfs_emit() knows the maximum of the temporary buffer used for outputting sysfs content and avoids overrunning the buffer length. Signed-off-by: Like Xu <likexu@tencent.com> Link: https://lore.kernel.org/r/20230625073438.57427-1-likexu@tencent.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-07-17Linux 6.5-rc2Linus Torvalds1-1/+1
2023-07-17Merge tag 'xtensa-20230716' of https://github.com/jcmvbkbc/linux-xtensaLinus Torvalds3-22/+18
Pull xtensa fixes from Max Filippov: - fix interaction between unaligned exception handler and load/store exception handler - fix parsing ISS network interface specification string - add comment about etherdev freeing to ISS network driver * tag 'xtensa-20230716' of https://github.com/jcmvbkbc/linux-xtensa: xtensa: fix unaligned and load/store configuration interaction xtensa: ISS: fix call to split_if_spec xtensa: ISS: add comment about etherdev freeing
2023-07-16Merge tag 'perf_urgent_for_v6.5_rc2' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fix from Borislav Petkov: - Fix a lockdep warning when the event given is the first one, no event group exists yet but the code still goes and iterates over event siblings * tag 'perf_urgent_for_v6.5_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix lockdep warning in for_each_sibling_event() on SPR
2023-07-16Merge tag 'objtool_urgent_for_v6.5_rc2' of ↵Linus Torvalds2-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool fixes from Borislav Petkov: - Mark copy_iovec_from_user() __noclone in order to prevent gcc from doing an inter-procedural optimization and confuse objtool - Initialize struct elf fully to avoid build failures * tag 'objtool_urgent_for_v6.5_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: iov_iter: Mark copy_iovec_from_user() noclone objtool: initialize all of struct elf
2023-07-16Merge tag 'sched_urgent_for_v6.5_rc2' of ↵Linus Torvalds5-12/+29
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Borislav Petkov: - Remove a cgroup from under a polling process properly - Fix the idle sibling selection * tag 'sched_urgent_for_v6.5_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/psi: use kernfs polling functions for PSI trigger polling sched/fair: Use recent_used_cpu to test p->cpus_ptr
2023-07-16Merge tag 'pinctrl-v6.5-2' of ↵Linus Torvalds4-55/+63
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control fixes from Linus Walleij: "I'm mostly on vacation but what would vacation be without a few critical fixes so people can use their gaming laptops when hiding away from the sun (or rain)? - Fix a really annoying interrupt storm in the AMD driver affecting Asus TUF gaming notebooks - Fix device tree parsing in the Renesas driver" * tag 'pinctrl-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: amd: Unify debounce handling into amd_pinconf_set() pinctrl: amd: Drop pull up select configuration pinctrl: amd: Use amd_pinconf_set() for all config options pinctrl: amd: Only use special debounce behavior for GPIO 0 pinctrl: renesas: rzg2l: Handle non-unique subnode names pinctrl: renesas: rzv2m: Handle non-unique subnode names
2023-07-16Merge tag '6.5-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds7-31/+43
Pull smb client fixes from Steve French: - Two reconnect fixes: important fix to address inFlight count to leak (which can leak credits), and fix for better handling a deleted share - DFS fix - SMB1 cleanup fix - deferred close fix * tag '6.5-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: fix mid leak during reconnection after timeout threshold cifs: is_network_name_deleted should return a bool smb: client: fix missed ses refcounting smb: client: Fix -Wstringop-overflow issues cifs: if deferred close is disabled then close files immediately
2023-07-16Merge tag 'powerpc-6.5-3' of ↵Linus Torvalds6-46/+51
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix Speculation_Store_Bypass reporting in /proc/self/status on Power10 - Fix HPT with 4K pages since recent changes by implementing pmd_same() - Fix 64-bit native_hpte_remove() to be irq-safe Thanks to Aneesh Kumar K.V, Nageswara R Sastry, and Russell Currey. * tag 'powerpc-6.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/mm/book3s64/hash/4k: Add pmd_same callback for 4K page size powerpc/64e: Fix obtool warnings in exceptions-64e.S powerpc/security: Fix Speculation_Store_Bypass reporting on Power10 powerpc/64s: Fix native_hpte_remove() to be irq-safe
2023-07-16Merge tag 'hardening-v6.5-rc2' of ↵Linus Torvalds6-10/+11
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening fixes from Kees Cook: - Remove LTO-only suffixes from promoted global function symbols (Yonghong Song) - Remove unused .text..refcount section from vmlinux.lds.h (Petr Pavlu) - Add missing __always_inline to sparc __arch_xchg() (Arnd Bergmann) - Claim maintainership of string routines * tag 'hardening-v6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: sparc: mark __arch_xchg() as __always_inline MAINTAINERS: Foolishly claim maintainership of string routines kallsyms: strip LTO-only suffixes from promoted global functions vmlinux.lds.h: Remove a reference to no longer used sections .text..refcount
2023-07-16Merge tag 'probes-fixes-v6.5-rc1-2' of ↵Linus Torvalds6-29/+24
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probe fixes from Masami Hiramatsu: - fprobe: Add a comment why fprobe will be skipped if another kprobe is running in fprobe_kprobe_handler(). - probe-events: Fix some issues related to fetch-arguments: - Fix double counting of the string length for user-string and symstr. This will require longer buffer in the array case. - Fix not to count error code (minus value) for the total used length in array argument. This makes the total used length shorter. - Fix to update dynamic used data size counter only if fetcharg uses the dynamic size data. This may mis-count the used dynamic data size and corrupt data. - Revert "tracing: Add "(fault)" name injection to kernel probes" because that did not work correctly with a bug, and we agreed the current '(fault)' output (instead of '"(fault)"' like a string) explains what happened more clearly. - Fix to record 0-length (means fault access) data_loc data in fetch function itself, instead of store_trace_args(). If we record an array of string, this will fix to save fault access data on each entry of the array correctly. * tag 'probes-fixes-v6.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if fails Revert "tracing: Add "(fault)" name injection to kernel probes" tracing/probes: Fix to update dynamic data counter if fetcharg uses it tracing/probes: Fix not to count error code to total length tracing/probes: Fix to avoid double count of the string length on the array fprobes: Add a comment why fprobe_kprobe_handler exits if kprobe is running
2023-07-15Merge tag 'spi-fix-v6.5-rc1' of ↵Linus Torvalds4-2/+12
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi fixes from Mark Brown: "A couple of fairly minor driver specific fixes here, plus a bunch of maintainership and admin updates. Nothing too remarkable" * tag 'spi-fix-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: mailmap: add entry for Jonas Gorski MAINTAINERS: add myself for spi-bcm63xx spi: s3c64xx: clear loopback bit after loopback test spi: bcm63xx: fix max prepend length MAINTAINERS: Add myself as a maintainer for Microchip SPI
2023-07-15Merge tag 'regmap-fix-v6.5-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap fix from Mark Brown: "One fix for an out of bounds access in the interupt code here" * tag 'regmap-fix-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap-irq: Fix out-of-bounds access when allocating config buffers
2023-07-15Merge tag 'iommu-fixes-v6.5-rc1' of ↵Linus Torvalds2-14/+16
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull iommu fixes from Joerg Roedel: - Fix a regression causing a crash on sysfs access of iommu-group specific files - Fix signedness bug in SVA code * tag 'iommu-fixes-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: iommu/sva: Fix signedness bug in iommu_sva_alloc_pasid() iommu: Fix crash during syfs iommu_groups/N/type
2023-07-15Merge tag 'x86_urgent_for_6.5_rc2' of ↵Linus Torvalds10-75/+120
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CFI fixes from Peter Zijlstra: "Fix kCFI/FineIBT weaknesses The primary bug Alyssa noticed was that with FineIBT enabled function prologues have a spurious ENDBR instruction: __cfi_foo: endbr64 subl $hash, %r10d jz 1f ud2 nop 1: foo: endbr64 <--- *sadface* This means that any indirect call that fails to target the __cfi symbol and instead targets (the regular old) foo+0, will succeed due to that second ENDBR. Fixing this led to the discovery of a single indirect call that was still doing this: ret_from_fork(). Since that's an assembly stub the compiler would not generate the proper kCFI indirect call magic and it would not get patched. Brian came up with the most comprehensive fix -- convert the thing to C with only a very thin asm wrapper. This ensures the kernel thread boostrap is a proper kCFI call. While discussing all this, Kees noted that kCFI hashes could/should be poisoned to seal all functions whose address is never taken, further limiting the valid kCFI targets -- much like we already do for IBT. So what was a 'simple' observation and fix cascaded into a bunch of inter-related CFI infrastructure fixes" * tag 'x86_urgent_for_6.5_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cfi: Only define poison_cfi() if CONFIG_X86_KERNEL_IBT=y x86/fineibt: Poison ENDBR at +0 x86: Rewrite ret_from_fork() in C x86/32: Remove schedule_tail_wrapper() x86/cfi: Extend ENDBR sealing to kCFI x86/alternative: Rename apply_ibt_endbr() x86/cfi: Extend {JMP,CAKK}_NOSPEC comment
2023-07-15Merge tag 'scsi-fixes' of ↵Linus Torvalds18-131/+193
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "This is a bunch of small driver fixes and a larger rework of zone disk handling (which reaches into blk and nvme). The aacraid array-bounds fix is now critical since the security people turned on -Werror for some build tests, which now fail without it" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: storvsc: Handle SRB status value 0x30 scsi: block: Improve checks in blk_revalidate_disk_zones() scsi: block: virtio_blk: Set zone limits before revalidating zones scsi: block: nullblk: Set zone limits before revalidating zones scsi: nvme: zns: Set zone limits before revalidating zones scsi: sd_zbc: Set zone limits before revalidating zones scsi: ufs: core: Add support for qTimestamp attribute scsi: aacraid: Avoid -Warray-bounds warning scsi: ufs: ufs-mediatek: Add dependency for RESET_CONTROLLER scsi: ufs: core: Update contact email for monitor sysfs nodes scsi: scsi_debug: Remove dead code scsi: qla2xxx: Use vmalloc_array() and vcalloc() scsi: fnic: Use vmalloc_array() and vcalloc() scsi: qla2xxx: Fix error code in qla2x00_start_sp() scsi: qla2xxx: Silence a static checker warning scsi: lpfc: Fix a possible data race in lpfc_unregister_fcf_rescan()
2023-07-15Merge tag 'block-6.5-2023-07-14' of git://git.kernel.dk/linuxLinus Torvalds15-50/+136
Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - Don't require quirk to use duplicate namespace identifiers (Christoph, Sagi) - One more BOGUS_NID quirk (Pankaj) - IO timeout and error hanlding fixes for PCI (Keith) - Enhanced metadata format mask fix (Ankit) - Association race condition fix for fibre channel (Michael) - Correct debugfs error checks (Minjie) - Use PAGE_SECTORS_SHIFT where needed (Damien) - Reduce kernel logs for legacy nguid attribute (Keith) - Use correct dma direction when unmapping metadata (Ming) - Fix for a flush handling regression in this release (Christoph) - Fix for batched request time stamping (Chengming) - Fix for a regression in the mq-deadline position calculation (Bart) - Lockdep fix for blk-crypto (Eric) - Fix for a regression in the Amiga partition handling changes (Michael) * tag 'block-6.5-2023-07-14' of git://git.kernel.dk/linux: block: queue data commands from the flush state machine at the head blk-mq: fix start_time_ns and alloc_time_ns for pre-allocated rq nvme-pci: fix DMA direction of unmapping integrity data nvme: don't reject probe due to duplicate IDs for single-ported PCIe devices block/mq-deadline: Fix a bug in deadline_from_pos() nvme: ensure disabling pairs with unquiesce nvme-fc: fix race between error recovery and creating association nvme-fc: return non-zero status code when fails to create association nvme: fix parameter check in nvme_fault_inject_init() nvme: warn only once for legacy uuid attribute block: remove dead struc request->completion_data field nvme: fix the NVME_ID_NS_NVM_STS_MASK definition nvmet: use PAGE_SECTORS_SHIFT nvme: add BOGUS_NID quirk for Samsung SM953 blk-crypto: use dynamic lock class for blk_crypto_profile::lock block/partition: fix signedness issue for Amiga partitions
2023-07-15Merge tag 'io_uring-6.5-2023-07-14' of git://git.kernel.dk/linuxLinus Torvalds1-2/+13
Pull io_uring fix from Jens Axboe: "Just a single tweak for the wait logic in io_uring" * tag 'io_uring-6.5-2023-07-14' of git://git.kernel.dk/linux: io_uring: Use io_schedule* in cqring wait
2023-07-14Merge tag 'riscv-for-linus-6.5-rc2' of ↵Linus Torvalds4-12/+4
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - fix a formatting error in the hwprobe documentation - fix a spurious warning in the RISC-V PMU driver - fix memory detection on rv32 (problem does not manifest on any known system) - avoid parsing legacy parsing of I in ACPI ISA strings * tag 'riscv-for-linus-6.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: RISC-V: Don't include Zicsr or Zifencei in I from ACPI riscv: mm: fix truncation warning on RV32 perf: RISC-V: Remove PERF_HES_STOPPED flag checking in riscv_pmu_start() Documentation: RISC-V: hwprobe: Fix a formatting error