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2021-02-09x86/platform/intel-mid: Remove unused leftovers (msic_battery)Andy Shevchenko
It seems msic_battery driver was never upstreamed. Why should we have dead code in the kernel? Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-09x86/platform/intel-mid: Remove unused leftovers (msic_ocd)Andy Shevchenko
It seems msic_ocd driver was never upstreamed. Why should we have dead code in the kernel? Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-09x86/platform/intel-mid: Remove unused leftovers (msic_audio)Andy Shevchenko
Commit 05f4434bc130 ("ASoC: Intel: remove mfld_machine") removed the driver, no need to have support files for it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-09Merge tag 'ib-drm-gpio-pdx86-rtc-wdt-v5.12-2' of ↵Rafael J. Wysocki
git://git.infradead.org/linux-platform-drivers-x86 Pull the first part of Intel MID outdated platforms removal from Andy Shevchenko: "The following is an automated git shortlog grouped by driver: drm/gma500: - Get rid of duplicate NULL checks - Convert to use new SCU IPC API gpio: - msic: Remove driver for deprecated platform - intel-mid: Remove driver for deprecated platform intel_mid_powerbtn: - Remove driver for deprecated platform intel_mid_thermal: - Remove driver for deprecated platform intel_scu_wdt: - Drop mistakenly added const - Get rid of custom x86 model comparison - Drop SCU notification - Move driver from arch/x86 rtc: - mrst: Remove driver for deprecated platform watchdog: - intel-mid_wdt: Postpone IRQ handler registration till SCU is ready - intel_scu_watchdog: Remove driver for deprecated platform" * tag 'ib-drm-gpio-pdx86-rtc-wdt-v5.12-2' of git://git.infradead.org/linux-platform-drivers-x86: platform/x86: intel_scu_wdt: Drop mistakenly added const platform/x86: intel_scu_wdt: Get rid of custom x86 model comparison platform/x86: intel_scu_wdt: Drop SCU notification platform/x86: intel_scu_wdt: Move driver from arch/x86 watchdog: intel-mid_wdt: Postpone IRQ handler registration till SCU is ready watchdog: intel_scu_watchdog: Remove driver for deprecated platform rtc: mrst: Remove driver for deprecated platform platform/x86: intel_mid_powerbtn: Remove driver for deprecated platform platform/x86: intel_mid_thermal: Remove driver for deprecated platform gpio: msic: Remove driver for deprecated platform gpio: intel-mid: Remove driver for deprecated platform drm/gma500: Get rid of duplicate NULL checks drm/gma500: Convert to use new SCU IPC API
2021-02-09KVM: x86/xen: Allow reset of Xen attributesDavid Woodhouse
In order to support Xen SHUTDOWN_soft_reset (for guest kexec, etc.) the VMM needs to be able to tear everything down and return the Xen features to a clean slate. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20210208232326.1830370-1-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86/mmu: Make HVA handler retpoline-friendlyMaciej S. Szmigiero
When retpolines are enabled they have high overhead in the inner loop inside kvm_handle_hva_range() that iterates over the provided memory area. Let's mark this function and its TDP MMU equivalent __always_inline so compiler will be able to change the call to the actual handler function inside each of them into a direct one. This significantly improves performance on the unmap test on the existing kernel memslot code (tested on a Xeon 8167M machine): 30 slots in use: Test Before After Improvement Unmap 0.0353s 0.0334s 5% Unmap 2M 0.00104s 0.000407s 61% 509 slots in use: Test Before After Improvement Unmap 0.0742s 0.0740s None Unmap 2M 0.00221s 0.00159s 28% Looks like having an indirect call in these functions (and, so, a retpoline) might have interfered with unrolling of the whole loop in the CPU. Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <732d3fe9eb68aa08402a638ab0309199fa89ae56.1612810129.git.maciej.szmigiero@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Drop hv_vcpu_to_vcpu() helperVitaly Kuznetsov
hv_vcpu_to_vcpu() helper is only used by other helpers and is not very complex, we can drop it without much regret. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-16-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Allocate Hyper-V context lazilyVitaly Kuznetsov
Hyper-V context is only needed for guests which use Hyper-V emulation in KVM (e.g. Windows/Hyper-V guests) so we don't actually need to allocate it in kvm_arch_vcpu_create(), we can postpone the action until Hyper-V specific MSRs are accessed or SynIC is enabled. Once allocated, let's keep the context alive for the lifetime of the vCPU as an attempt to free it would require additional synchronization with other vCPUs and normally it is not supposed to happen. Note, Hyper-V style hypercall enablement is done by writing to HV_X64_MSR_GUEST_OS_ID so we don't need to worry about allocating Hyper-V context from kvm_hv_hypercall(). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-15-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Make Hyper-V emulation enablement conditionalVitaly Kuznetsov
Hyper-V emulation is enabled in KVM unconditionally. This is bad at least from security standpoint as it is an extra attack surface. Ideally, there should be a per-VM capability explicitly enabled by VMM but currently it is not the case and we can't mandate one without breaking backwards compatibility. We can, however, check guest visible CPUIDs and only enable Hyper-V emulation when "Hv#1" interface was exposed in HYPERV_CPUID_INTERFACE. Note, VMMs are free to act in any sequence they like, e.g. they can try to set MSRs first and CPUIDs later so we still need to allow the host to read/write Hyper-V specific MSRs unconditionally. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-14-vkuznets@redhat.com> [Add selftest vcpu_set_hv_cpuid API to avoid breaking xen_vmcall_test. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Allocate 'struct kvm_vcpu_hv' dynamicallyVitaly Kuznetsov
Hyper-V context is only needed for guests which use Hyper-V emulation in KVM (e.g. Windows/Hyper-V guests). 'struct kvm_vcpu_hv' is, however, quite big, it accounts for more than 1/4 of the total 'struct kvm_vcpu_arch' which is also quite big already. This all looks like a waste. Allocate 'struct kvm_vcpu_hv' dynamically. This patch does not bring any (intentional) functional change as we still allocate the context unconditionally but it paves the way to doing that only when needed. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-13-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V contextVitaly Kuznetsov
Currently, Hyper-V context is part of 'struct kvm_vcpu_arch' and is always available. As a preparation to allocating it dynamically, check that it is not NULL at call sites which can normally proceed without it i.e. the behavior is identical to the situation when Hyper-V emulation is not being used by the guest. When Hyper-V context for a particular vCPU is not allocated, we may still need to get 'vp_index' from there. E.g. in a hypothetical situation when Hyper-V emulation was enabled on one CPU and wasn't on another, Hyper-V style send-IPI hypercall may still be used. Luckily, vp_index is always initialized to kvm_vcpu_get_idx() and can only be changed when Hyper-V context is present. Introduce kvm_hv_get_vpindex() helper for simplification. No functional change intended. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-12-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Always use to_hv_vcpu() accessor to get to 'struct ↵Vitaly Kuznetsov
kvm_vcpu_hv' As a preparation to allocating Hyper-V context dynamically, make it clear who's the user of the said context. No functional change intended. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-11-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Stop shadowing global 'current_vcpu' variableVitaly Kuznetsov
'current_vcpu' variable in KVM is a per-cpu pointer to the currently scheduled vcpu. kvm_hv_flush_tlb()/kvm_hv_send_ipi() functions used to have local 'vcpu' variable to iterate over vCPUs but it's gone now and there's no need to use anything but the standard 'vcpu' as an argument. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-10-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Introduce to_kvm_hv() helperVitaly Kuznetsov
Spelling '&kvm->arch.hyperv' correctly is hard. Also, this makes the code more consistent with vmx/svm where to_kvm_vmx()/to_kvm_svm() are already being used. Opportunistically change kvm_hv_msr_{get,set}_crash_{data,ctl}() and kvm_hv_msr_set_crash_data() to take 'kvm' instead of 'vcpu' as these MSRs are partition wide. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-9-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Rename vcpu_to_hv_syndbg() to to_hv_syndbg()Vitaly Kuznetsov
vcpu_to_hv_syndbg()'s argument is always 'vcpu' so there's no need to have an additional prefix. Also, this makes the code more consistent with vmx/svm where to_vmx()/to_svm() are being used. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-8-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Rename vcpu_to_stimer()/stimer_to_vcpu()Vitaly Kuznetsov
vcpu_to_stimers()'s argument is almost always 'vcpu' so there's no need to have an additional prefix. Also, this makes the naming more consistent with to_hv_vcpu()/to_hv_synic(). Rename stimer_to_vcpu() to hv_stimer_to_vcpu() for consitency. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-7-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Rename vcpu_to_synic()/synic_to_vcpu()Vitaly Kuznetsov
vcpu_to_synic()'s argument is almost always 'vcpu' so there's no need to have an additional prefix. Also, as this is used outside of hyper-v emulation code, add '_hv_' part to make it clear what this s. This makes the naming more consistent with to_hv_vcpu(). Rename synic_to_vcpu() to hv_synic_to_vcpu() for consistency. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-6-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Rename vcpu_to_hv_vcpu() to to_hv_vcpu()Vitaly Kuznetsov
vcpu_to_hv_vcpu()'s argument is almost always 'vcpu' so there's no need to have an additional prefix. Also, this makes the code more consistent with vmx/svm where to_vmx()/to_svm() are being used. No functional change intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-5-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: hyper-v: Drop unused kvm_hv_vapic_assist_page_enabled()Vitaly Kuznetsov
kvm_hv_vapic_assist_page_enabled() seems to be unused since its introduction in commit 10388a07164c1 ("KVM: Add HYPER-V apic access MSRs"), drop it. Reported-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210126134816.1880136-4-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: Raise the maximum number of user memslotsVitaly Kuznetsov
Current KVM_USER_MEM_SLOTS limits are arch specific (512 on Power, 509 on x86, 32 on s390, 16 on MIPS) but they don't really need to be. Memory slots are allocated dynamically in KVM when added so the only real limitation is 'id_to_index' array which is 'short'. We don't have any other KVM_MEM_SLOTS_NUM/KVM_USER_MEM_SLOTS-sized statically defined structures. Low KVM_USER_MEM_SLOTS can be a limiting factor for some configurations. In particular, when QEMU tries to start a Windows guest with Hyper-V SynIC enabled and e.g. 256 vCPUs the limit is hit as SynIC requires two pages per vCPU and the guest is free to pick any GFN for each of them, this fragments memslots as QEMU wants to have a separate memslot for each of these pages (which are supposed to act as 'overlay' pages). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210127175731.2020089-3-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: move kvm_inject_gp up from kvm_set_dr to callersPaolo Bonzini
Push the injection of #GP up to the callers, so that they can just use kvm_complete_insn_gp. __kvm_set_dr is pretty much what the callers can use together with kvm_complete_insn_gp, so rename it to kvm_set_dr and drop the old kvm_set_dr wrapper. This also allows nested VMX code, which really wanted to use __kvm_set_dr, to use the right function. While at it, remove the kvm_require_dr() check from the SVM interception. The APM states: All normal exception checks take precedence over the SVM intercepts. which includes the CR4.DE=1 #UD. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: reading DR cannot failPaolo Bonzini
kvm_get_dr and emulator_get_dr except an in-range value for the register number so they cannot fail. Change the return type to void. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: SVM: Remove an unnecessary forward declarationSean Christopherson
Drop a defunct forward declaration of svm_complete_interrupts(). No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210205005750.3841462-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: SVM: Move AVIC vCPU kicking snippet to helper functionSean Christopherson
Add a helper function to handle kicking non-running vCPUs when sending virtual IPIs. A future patch will change SVM's interception functions to take @vcpu instead of @svm, at which piont declaring and modifying 'vcpu' in a case statement is confusing, and potentially dangerous. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210205005750.3841462-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: Restore all 64 bits of DR6 and DR7 during RSM on x86-64Sean Christopherson
Restore the full 64-bit values of DR6 and DR7 when emulating RSM on x86-64, as defined by both Intel's SDM and AMD's APM. Note, bits 63:32 of DR6 and DR7 are reserved, so this is a glorified nop unless the SMM handler is poking into SMRAM, which it most definitely shouldn't be doing since both Intel and AMD list the DR6 and DR7 fields as read-only. Fixes: 660a5d517aaa ("KVM: x86: save/load state on SMM switch") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210205012458.3872687-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86: Remove misleading DR6/DR7 adjustments from RSM emulationSean Christopherson
Drop the DR6/7 volatile+fixed bits adjustments in RSM emulation, which are redundant and misleading. The necessary adjustments are made by kvm_set_dr(), which properly sets the fixed bits that are conditional on the vCPU model. Note, KVM incorrectly reads only bits 31:0 of the DR6/7 fields when emulating RSM on x86-64. On the plus side for this change, that bug makes removing "& DRx_VOLATILE" a nop. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210205012458.3872687-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86/xen: Use hva_t for holding hypercall page addressSean Christopherson
Use hva_t, a.k.a. unsigned long, for the local variable that holds the hypercall page address. On 32-bit KVM, gcc complains about using a u64 due to the implicit cast from a 64-bit value to a 32-bit pointer. arch/x86/kvm/xen.c: In function ‘kvm_xen_write_hypercall_page’: arch/x86/kvm/xen.c:300:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] 300 | page = memdup_user((u8 __user *)blob_addr, PAGE_SIZE); Cc: Joao Martins <joao.m.martins@oracle.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Fixes: 23200b7a30de ("KVM: x86/xen: intercept xen hypercalls if enabled") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210208201502.1239867-1-seanjc@google.com> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09KVM: x86/xen: Remove extra unlock in kvm_xen_hvm_set_attr()David Woodhouse
This accidentally ended up locking and then immediately unlocking kvm->lock at the beginning of the function. Fix it. Fixes: a76b9641ad1c ("KVM: x86/xen: add KVM_XEN_HVM_SET_ATTR/KVM_XEN_HVM_GET_ATTR") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <20210208232326.1830370-2-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-09x86/build: Disable CET instrumentation in the kernel for 32-bit tooBorislav Petkov
Commit 20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel") disabled CET instrumentation which gets added by default by the Ubuntu gcc9 and 10 by default, but did that only for 64-bit builds. It would still fail when building a 32-bit target. So disable CET for all x86 builds. Fixes: 20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel") Reported-by: AC <achirvasub@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: AC <achirvasub@gmail.com> Link: https://lkml.kernel.org/r/YCCIgMHkzh/xT4ex@arch-chirva.localdomain
2021-02-09x86/acrn: Introduce hypercall interfacesShuo Liu
The Service VM communicates with the hypervisor via conventional hypercalls. VMCALL instruction is used to make the hypercalls. ACRN hypercall ABI: * Hypercall number is in R8 register. * Up to 2 parameters are in RDI and RSI registers. * Return value is in RAX register. Introduce the ACRN hypercall interfaces. Because GCC doesn't support R8 register as direct register constraints, use supported constraint as input with a explicit MOV to R8 in beginning of asm. Cc: Dave Hansen <dave.hansen@intel.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Fengwei Yin <fengwei.yin@intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Yu Wang <yu1.wang@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Segher Boessenkool <segher@kernel.crashing.org> Originally-by: Yakui Zhao <yakui.zhao@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> Link: https://lore.kernel.org/r/20210207031040.49576-5-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09x86/acrn: Introduce acrn_cpuid_base() and hypervisor feature bitsYin Fengwei
ACRN Hypervisor reports hypervisor features via CPUID leaf 0x40000001 which is similar to KVM. A VM can check if it's the privileged VM using the feature bits. The Service VM is the only privileged VM by design. Cc: Dave Hansen <dave.hansen@intel.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Fengwei Yin <fengwei.yin@intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Yu Wang <yu1.wang@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Yin Fengwei <fengwei.yin@intel.com> Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> Link: https://lore.kernel.org/r/20210207031040.49576-4-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09x86/acrn: Introduce acrn_{setup, remove}_intr_handler()Shuo Liu
The ACRN Hypervisor builds an I/O request when a trapped I/O access happens in User VM. Then, ACRN Hypervisor issues an upcall by sending a notification interrupt to the Service VM. HSM in the Service VM needs to hook the notification interrupt to handle I/O requests. Notification interrupts from ACRN Hypervisor are already supported and a, currently uninitialized, callback called. Export two APIs for HSM to setup/remove its callback. Cc: Dave Hansen <dave.hansen@intel.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Fengwei Yin <fengwei.yin@intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Yu Wang <yu1.wang@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Originally-by: Yakui Zhao <yakui.zhao@intel.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> Link: https://lore.kernel.org/r/20210207031040.49576-3-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-08KVM: x86: compile out TDP MMU on 32-bit systemsPaolo Bonzini
The TDP MMU assumes that it can do atomic accesses to 64-bit PTEs. Rather than just disabling it, compile it out completely so that it is possible to use for example 64-bit xchg. To limit the number of stubs, wrap all accesses to tdp_mmu_enabled or tdp_mmu_page with a function. Calls to all other functions in tdp_mmu.c are eliminated and do not even reach the linker. Reviewed-by: Sean Christopherson <seanjc@google.com> Tested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-08x86/sgx: Maintain encl->refcount for each encl->mm_list entryJarkko Sakkinen
This has been shown in tests: [ +0.000008] WARNING: CPU: 3 PID: 7620 at kernel/rcu/srcutree.c:374 cleanup_srcu_struct+0xed/0x100 This is essentially a use-after free, although SRCU notices it as an SRCU cleanup in an invalid context. == Background == SGX has a data structure (struct sgx_encl_mm) which keeps per-mm SGX metadata. This is separate from struct sgx_encl because, in theory, an enclave can be mapped from more than one mm. sgx_encl_mm includes a pointer back to the sgx_encl. This means that sgx_encl must have a longer lifetime than all of the sgx_encl_mm's that point to it. That's usually the case: sgx_encl_mm is freed only after the mmu_notifier is unregistered in sgx_release(). However, there's a race. If the process is exiting, sgx_mmu_notifier_release() can be called in parallel with sgx_release() instead of being called *by* it. The mmu_notifier path keeps encl_mm alive past when sgx_encl can be freed. This inverts the lifetime rules and means that sgx_mmu_notifier_release() can access a freed sgx_encl. == Fix == Increase encl->refcount when encl_mm->encl is established. Release this reference when encl_mm is freed. This ensures that encl outlives encl_mm. [ bp: Massage commit message. ] Fixes: 1728ab54b4be ("x86/sgx: Add a page reclaimer") Reported-by: Haitao Huang <haitao.huang@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20210207221401.29933-1-jarkko@kernel.org
2021-02-08cpufreq: ACPI: Update arch scale-invariance max perf ratio if CPPC is not thereRafael J. Wysocki
If the maximum performance level taken for computing the arch_max_freq_ratio value used in the x86 scale-invariance code is higher than the one corresponding to the cpuinfo.max_freq value coming from the acpi_cpufreq driver, the scale-invariant utilization falls below 100% even if the CPU runs at cpuinfo.max_freq or slightly faster, which causes the schedutil governor to select a frequency below cpuinfo.max_freq. That frequency corresponds to a frequency table entry below the maximum performance level necessary to get to the "boost" range of CPU frequencies which prevents "boost" frequencies from being used in some workloads. While this issue is related to scale-invariance, it may be amplified by commit db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate") from the 5.10 development cycle which made it extremely easy to default to schedutil even if the preferred driver is acpi_cpufreq as long as intel_pstate is built too, because the mere presence of the latter effectively removes the ondemand governor from the defaults. Distro kernels are likely to include both intel_pstate and acpi_cpufreq on x86, so their users who cannot use intel_pstate or choose to use acpi_cpufreq may easily be affectecd by this issue. If CPPC is available, it can be used to address this issue by extending the frequency tables created by acpi_cpufreq to cover the entire available frequency range (including "boost" frequencies) for each CPU, but if CPPC is not there, acpi_cpufreq has no idea what the maximum "boost" frequency is and the frequency tables created by it cannot be extended in a meaningful way, so in that case make it ask the arch scale-invariance code to to use the "nominal" performance level for CPU utilization scaling in order to avoid the issue at hand. Fixes: db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Giovanni Gherdovich <ggherdovich@suse.cz> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-02-08module: remove EXPORT_UNUSED_SYMBOL*Christoph Hellwig
EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the unused functionality as we generally just remove unused code anyway. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08module: remove EXPORT_SYMBOL_GPL_FUTUREChristoph Hellwig
As far as I can tell this has never been used at all, and certainly not any time recently. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2021-02-08thermal: Move therm_throt there from x86/mceBorislav Petkov
This functionality has nothing to do with MCE, move it to the thermal framework and untangle it from MCE. Requested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Link: https://lkml.kernel.org/r/20210202121003.GD18075@zn.tnic
2021-02-08x86/mce: Get rid of mcheck_intel_therm_init()Borislav Petkov
Move the APIC_LVTTHMR read which needs to happen on the BSP, to intel_init_thermal(). One less boot dependency. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Link: https://lkml.kernel.org/r/20210201142704.12495-2-bp@alien8.de
2021-02-07Merge tag 'core_urgent_for_v5.11_rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull syscall entry fixes from Borislav Petkov: - For syscall user dispatch, separate prctl operation from syscall redirection range specification before the API has been made official in 5.11. - Ensure tasks using the generic syscall code do trap after returning from a syscall when single-stepping is requested. * tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: entry: Use different define for selector variable in SUD entry: Ensure trap after single-step on system call return
2021-02-07Merge tag 'x86_urgent_for_v5.11_rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "I hope this is the last batch of x86/urgent updates for this round: - Remove superfluous EFI PGD range checks which lead to those assertions failing with certain kernel configs and LLVM. - Disable setting breakpoints on facilities involved in #DB exception handling to avoid infinite loops. - Add extra serialization to non-serializing MSRs (IA32_TSC_DEADLINE and x2 APIC MSRs) to adhere to SDM's recommendation and avoid any theoretical issues. - Re-add the EPB MSR reading on turbostat so that it works on older kernels which don't have the corresponding EPB sysfs file. - Add Alder Lake to the list of CPUs which support split lock. - Fix %dr6 register handling in order to be able to set watchpoints with gdb again. - Disable CET instrumentation in the kernel so that gcc doesn't add ENDBR64 to kernel code and thus confuse tracing" * tag 'x86_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efi: Remove EFI PGD build time checks x86/debug: Prevent data breakpoints on cpu_dr7 x86/debug: Prevent data breakpoints on __per_cpu_offset x86/apic: Add extra serialization for non-serializing MSRs tools/power/turbostat: Fallback to an MSR read for EPB x86/split_lock: Enable the split lock feature on another Alder Lake CPU x86/debug: Fix DR6 handling x86/build: Disable CET instrumentation in the kernel
2021-02-06x86/efi: Remove EFI PGD build time checksBorislav Petkov
With CONFIG_X86_5LEVEL, CONFIG_UBSAN and CONFIG_UBSAN_UNSIGNED_OVERFLOW enabled, clang fails the build with x86_64-linux-ld: arch/x86/platform/efi/efi_64.o: in function `efi_sync_low_kernel_mappings': efi_64.c:(.text+0x22c): undefined reference to `__compiletime_assert_354' which happens due to -fsanitize=unsigned-integer-overflow being enabled: -fsanitize=unsigned-integer-overflow: Unsigned integer overflow, where the result of an unsigned integer computation cannot be represented in its type. Unlike signed integer overflow, this is not undefined behavior, but it is often unintentional. This sanitizer does not check for lossy implicit conversions performed before such a computation (see -fsanitize=implicit-conversion). and that fires when the (intentional) EFI_VA_START/END defines overflow an unsigned long, leading to the assertion expressions not getting optimized away (on GCC they do)... However, those checks are superfluous: the runtime services mapping code already makes sure the ranges don't overshoot EFI_VA_END as the EFI mapping range is hardcoded. On each runtime services call, it is switched to the EFI-specific PGD and even if mappings manage to escape that last PGD, this won't remain unnoticed for long. So rip them out. See https://github.com/ClangBuiltLinux/linux/issues/256 for more info. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: http://lkml.kernel.org/r/20210107223424.4135538-1-arnd@kernel.org
2021-02-06entry: Ensure trap after single-step on system call returnGabriel Krisman Bertazi
Commit 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") introduced a bug on architectures using the generic syscall entry code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall return after receiving a TIF_SINGLESTEP. The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to cause the trap after a system call is executed, but since the above commit, the syscall call handler only checks for the SYSCALL_WORK flags on the exit work. Split the meaning of TIF_SINGLESTEP such that it only means single-step mode, and create a new type of SYSCALL_WORK to request a trap immediately after a syscall in single-step mode. In the current implementation, the SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity. Update x86 to flip this bit when a tracer enables single stepping. Fixes: 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com
2021-02-05x86/debug: Prevent data breakpoints on cpu_dr7Lai Jiangshan
local_db_save() is called at the start of exc_debug_kernel(), reads DR7 and disables breakpoints to prevent recursion. When running in a guest (X86_FEATURE_HYPERVISOR), local_db_save() reads the per-cpu variable cpu_dr7 to check whether a breakpoint is active or not before it accesses DR7. A data breakpoint on cpu_dr7 therefore results in infinite #DB recursion. Disallow data breakpoints on cpu_dr7 to prevent that. Fixes: 84b6a3491567a("x86/entry: Optimize local_db_save() for virt") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210204152708.21308-2-jiangshanlai@gmail.com
2021-02-05x86/debug: Prevent data breakpoints on __per_cpu_offsetLai Jiangshan
When FSGSBASE is enabled, paranoid_entry() fetches the per-CPU GSBASE value via __per_cpu_offset or pcpu_unit_offsets. When a data breakpoint is set on __per_cpu_offset[cpu] (read-write operation), the specific CPU will be stuck in an infinite #DB loop. RCU will try to send an NMI to the specific CPU, but it is not working either since NMI also relies on paranoid_entry(). Which means it's undebuggable. Fixes: eaad981291ee3("x86/entry/64: Introduce the FIND_PERCPU_BASE macro") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210204152708.21308-1-jiangshanlai@gmail.com
2021-02-05x86/Kconfig: Remove HPET_EMULATE_RTC depends on RTCAnand K Mistry
The RTC config option was removed in commit f52ef24be21a ("rtc/alpha: remove legacy rtc driver") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20210204183205.1.If5c6ded53a00ecad6a02a1e974316291cc0239d1@changeid
2021-02-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "x86 has lots of small bugfixes, mostly one liners. It's quite late in 5.11-rc but none of them are related to this merge window; it's just bugs coming in at the wrong time. Of note among the others is "KVM: x86: Allow guests to see MSR_IA32_TSX_CTRL even if tsx=off" that fixes a live migration failure seen on distros that hadn't switched to tsx=off right away. ARM: - Avoid clobbering extra registers on initialisation" [ Sean Christopherson notes that commit 943dea8af21b ("KVM: x86: Update emulator context mode if SYSENTER xfers to 64-bit mode") should have had authorship credited to Jonny Barker, not to him. - Linus ] * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Set so called 'reserved CR3 bits in LM mask' at vCPU reset KVM: x86/mmu: Fix TDP MMU zap collapsible SPTEs KVM: x86: cleanup CR3 reserved bits checks KVM: SVM: Treat SVM as unsupported when running as an SEV guest KVM: x86: Update emulator context mode if SYSENTER xfers to 64-bit mode KVM: x86: Supplement __cr4_reserved_bits() with X86_FEATURE_PCID check KVM/x86: assign hva with the right value to vm_munmap the pages KVM: x86: Allow guests to see MSR_IA32_TSX_CTRL even if tsx=off Fix unsynchronized access to sev members through svm_register_enc_region KVM: Documentation: Fix documentation for nested. KVM: x86: fix CPUID entries returned by KVM_GET_CPUID2 ioctl KVM: arm64: Don't clobber x4 in __do_hyp_init
2021-02-05x86/sgx: Drop racy follow_pfn() checkDaniel Vetter
PTE insertion is fundamentally racy, and this check doesn't do anything useful. Quoting Sean: "Yeah, it can be whacked. The original, never-upstreamed code asserted that the resolved PFN matched the PFN being installed by the fault handler as a sanity check on the SGX driver's EPC management. The WARN assertion got dropped for whatever reason, leaving that useless chunk." Jason stumbled over this as a new user of follow_pfn(), and I'm trying to get rid of unsafe callers of that function so it can be locked down further. This is independent prep work for the referenced patch series: https://lore.kernel.org/dri-devel/20201127164131.2244124-1-daniel.vetter@ffwll.ch/ Fixes: 947c6e11fa43 ("x86/sgx: Add ptrace() support for the SGX driver") Reported-by: Jason Gunthorpe <jgg@ziepe.ca> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Link: https://lkml.kernel.org/r/20210204184519.2809313-1-daniel.vetter@ffwll.ch
2021-02-05x86/asm: Fixup TASK_SIZE_MAX commentAlexey Dobriyan
Comment says "by preventing anything executable" which is not true. Even PROT_NONE mapping can't be installed at (1<<47 - 4096). mmap(0x7ffffffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = -1 ENOMEM [ bp: Fixup to the moved location in page_64_types.h. ] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200305181719.GA5490@avx2
2021-02-04x86/apic: Add extra serialization for non-serializing MSRsDave Hansen
Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for MFENCE; LFENCE. Short summary: we have special MSRs that have weaker ordering than all the rest. Add fencing consistent with current SDM recommendations. This is not known to cause any issues in practice, only in theory. Longer story below: The reason the kernel uses a different semantic is that the SDM changed (roughly in late 2017). The SDM changed because folks at Intel were auditing all of the recommended fences in the SDM and realized that the x2apic fences were insufficient. Why was the pain MFENCE judged insufficient? WRMSR itself is normally a serializing instruction. No fences are needed because the instruction itself serializes everything. But, there are explicit exceptions for this serializing behavior written into the WRMSR instruction documentation for two classes of MSRs: IA32_TSC_DEADLINE and the X2APIC MSRs. Back to x2apic: WRMSR is *not* serializing in this specific case. But why is MFENCE insufficient? MFENCE makes writes visible, but only affects load/store instructions. WRMSR is unfortunately not a load/store instruction and is unaffected by MFENCE. This means that a non-serializing WRMSR could be reordered by the CPU to execute before the writes made visible by the MFENCE have even occurred in the first place. This means that an x2apic IPI could theoretically be triggered before there is any (visible) data to process. Does this affect anything in practice? I honestly don't know. It seems quite possible that by the time an interrupt gets to consume the (not yet) MFENCE'd data, it has become visible, mostly by accident. To be safe, add the SDM-recommended fences for all x2apic WRMSRs. This also leaves open the question of the _other_ weakly-ordered WRMSR: MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as the x2APIC MSRs, it seems substantially less likely to be a problem in practice. While writes to the in-memory Local Vector Table (LVT) might theoretically be reordered with respect to a weakly-ordered WRMSR like TSC_DEADLINE, the SDM has this to say: In x2APIC mode, the WRMSR instruction is used to write to the LVT entry. The processor ensures the ordering of this write and any subsequent WRMSR to the deadline; no fencing is required. But, that might still leave xAPIC exposed. The safest thing to do for now is to add the extra, recommended LFENCE. [ bp: Massage commit message, fix typos, drop accidentally added newline to tools/arch/x86/include/asm/barrier.h. ] Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com