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2021-10-26x86/fpu: Reset permission and fpstate on exec()Chang S. Bae
On exec(), extended register states saved in the buffer is cleared. With dynamic features, each task carries variables besides the register states. The struct fpu has permission information and struct fpstate contains buffer size and feature masks. They are all dynamically updated with dynamic features. Reset the current task's entire FPU data before an exec() so that the new task starts with default permission and fpstate. Rename the register state reset function because the old naming confuses as it does not reset struct fpstate. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-12-chang.seok.bae@intel.com
2021-10-26x86/fpu: Prepare fpu_clone() for dynamically enabled featuresThomas Gleixner
The default portion of the parent's FPU state is saved in a child task. With dynamic features enabled, the non-default portion is not saved in a child's fpstate because these register states are defined to be caller-saved. The new task's fpstate is therefore the default buffer. Fork inherits the permission of the parent. Also, do not use memcpy() when TIF_NEED_FPU_LOAD is set because it is invalid when the parent has dynamic features. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-11-chang.seok.bae@intel.com
2021-10-26x86/fpu/signal: Prepare for variable sigframe lengthChang S. Bae
The software reserved portion of the fxsave frame in the signal frame is copied from structures which have been set up at boot time. With dynamically enabled features the content of these structures is no longer correct because the xfeatures and size can be different per task. Calculate the software reserved portion at runtime and fill in the xfeatures and size values from the tasks active fpstate. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-10-chang.seok.bae@intel.com
2021-10-26x86/signal: Use fpu::__state_user_size for sigalt stack validationThomas Gleixner
Use the current->group_leader->fpu to check for pending permissions to use extended features and validate against the resulting user space size which is stored in the group leaders fpu struct as well. This prevents a task from installing a too small sized sigaltstack after permissions to use dynamically enabled features have been granted, but the task has not (yet) used a related instruction. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-9-chang.seok.bae@intel.com
2021-10-26x86/fpu: Add basic helpers for dynamically enabled featuresThomas Gleixner
To allow building up the infrastructure required to support dynamically enabled FPU features, add: - XFEATURES_MASK_DYNAMIC This constant will hold xfeatures which can be dynamically enabled. - fpu_state_size_dynamic() A static branch for 64-bit and a simple 'return false' for 32-bit. This helper allows to add dynamic-feature-specific changes to common code which is shared between 32-bit and 64-bit without #ifdeffery. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-8-chang.seok.bae@intel.com
2021-10-26x86/arch_prctl: Add controls for dynamic XSTATE componentsChang S. Bae
Dynamically enabled XSTATE features are by default disabled for all processes. A process has to request permission to use such a feature. To support this implement a architecture specific prctl() with the options: - ARCH_GET_XCOMP_SUPP Copies the supported feature bitmap into the user space provided u64 storage. The pointer is handed in via arg2 - ARCH_GET_XCOMP_PERM Copies the process wide permitted feature bitmap into the user space provided u64 storage. The pointer is handed in via arg2 - ARCH_REQ_XCOMP_PERM Request permission for a feature set. A feature set can be mapped to a facility, e.g. AMX, and can require one or more XSTATE components to be enabled. The feature argument is the number of the highest XSTATE component which is required for a facility to work. The request argument is not a user supplied bitmap because that makes filtering harder (think seccomp) and even impossible because to support 32bit tasks the argument would have to be a pointer. The permission mechanism works this way: Task asks for permission for a facility and kernel checks whether that's supported. If supported it does: 1) Check whether permission has already been granted 2) Compute the size of the required kernel and user space buffer (sigframe) size. 3) Validate that no task has a sigaltstack installed which is smaller than the resulting sigframe size 4) Add the requested feature bit(s) to the permission bitmap of current->group_leader->fpu and store the sizes in the group leaders fpu struct as well. If that is successful then the feature is still not enabled for any of the tasks. The first usage of a related instruction will result in a #NM trap. The trap handler validates the permission bit of the tasks group leader and if permitted it installs a larger kernel buffer and transfers the permission and size info to the new fpstate container which makes all the FPU functions which require per task information aware of the extended feature set. [ tglx: Adopted to new base code, added missing serialization, massaged namings, comments and changelog ] Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-7-chang.seok.bae@intel.com
2021-10-26x86/fpu: Add fpu_state_config::legacy_featuresThomas Gleixner
The upcoming prctl() which is required to request the permission for a dynamically enabled feature will also provide an option to retrieve the supported features. If the CPU does not support XSAVE, the supported features would be 0 even when the CPU supports FP and SSE. Provide separate storage for the legacy feature set to avoid that and fill in the bits in the legacy init function. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-6-chang.seok.bae@intel.com
2021-10-26x86/fpu: Add members to struct fpu to cache permission informationThomas Gleixner
Dynamically enabled features can be requested by any thread of a running process at any time. The request does neither enable the feature nor allocate larger buffers. It just stores the permission to use the feature by adding the features to the permission bitmap and by calculating the required sizes for kernel and user space. The reallocation of the kernel buffer happens when the feature is used for the first time which is caught by an exception. The permission bitmap is then checked and if the feature is permitted, then it becomes fully enabled. If not, the task dies similarly to a task which uses an undefined instruction. The size information is precomputed to allow proper sigaltstack size checks once the feature is permitted, but not yet in use because otherwise this would open race windows where too small stacks could be installed causing a later fail on signal delivery. Initialize them to the default feature set and sizes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-5-chang.seok.bae@intel.com
2021-10-26x86/fpu/xstate: Provide xstate_calculate_size()Chang S. Bae
Split out the size calculation from the paranoia check so it can be used for recalculating buffer sizes when dynamically enabled features are supported. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> [ tglx: Adopted to changed base code ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-4-chang.seok.bae@intel.com
2021-10-26x86/signal: Implement sigaltstack size validationThomas Gleixner
For historical reasons MINSIGSTKSZ is a constant which became already too small with AVX512 support. Add a mechanism to enforce strict checking of the sigaltstack size against the real size of the FPU frame. The strict check can be enabled via a config option and can also be controlled via the kernel command line option 'strict_sas_size' independent of the config switch. Enabling it might break existing applications which allocate a too small sigaltstack but 'work' because they never get a signal delivered. Though it can be handy to filter out binaries which are not yet aware of AT_MINSIGSTKSZ. Also the upcoming support for dynamically enabled FPU features requires a strict sanity check to ensure that: - Enabling of a dynamic feature, which changes the sigframe size fits into an enabled sigaltstack - Installing a too small sigaltstack after a dynamic feature has been added is not possible. Implement the base check which is controlled by config and command line options. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-3-chang.seok.bae@intel.com
2021-10-25trace/osnoise: Fix an ifdef commentDaniel Bristot de Oliveira
s/CONFIG_OSNOISE_TRAECR/CONFIG_OSNOISE_TRACER/ No functional changes. Link: https://lkml.kernel.org/r/33924a16f6e5559ce24952ca7d62561604bfd94a.1634308385.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-25signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved.Eric W. Biederman
Update save_v86_state to always complete all of it's work except possibly some of the copies to userspace even if save_v86_state takes a fault. This ensures that the kernel is always in a sane state, even if userspace has done something silly. When save_v86_state takes a fault update it to force userspace to take a SIGSEGV and terminate the userspace application. As Andy pointed out in review of the first version of this change there are races between sigaction and the application terinating. Now that the code has been modified to always perform all save_v86_state's work (except possibly copying to userspace) those races do not matter from a kernel perspective. Forcing the userspace application to terminate (by resetting it's handler to SIGDFL) is there to keep everything as close to the current behavior as possible while removing the unique (and difficult to maintain) use of do_exit. If this new SIGSEGV happens during handle_signal the next time around the exit_to_user_mode_loop, SIGSEGV will be delivered to userspace. All of the callers of handle_vm86_trap and handle_vm86_fault run the exit_to_user_mode_loop before they return to userspace any signal sent to the current task during their execution will be delivered to the current task before that tasks exits to usermode. Cc: Andy Lutomirski <luto@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: H Peter Anvin <hpa@zytor.com> v1: https://lkml.kernel.org/r/20211020174406.17889-10-ebiederm@xmission.com Link: https://lkml.kernel.org/r/877de1xcr6.fsf_-_@disp2133 Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-10-25signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ONEric W. Biederman
The function save_v86_state is only called when userspace was operating in vm86 mode before entering the kernel. Not having vm86 state in the task_struct should never happen. So transform the hand rolled BUG_ON into an actual BUG_ON to make it clear what is happening. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: H Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/20211020174406.17889-9-ebiederm@xmission.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2021-10-25x86/sev: Expose sev_es_ghcb_hv_call() for use by HyperVTianyu Lan
Hyper-V needs to issue the GHCB HV call in order to read/write MSRs in Isolation VMs. For that, expose sev_es_ghcb_hv_call(). The Hyper-V Isolation VMs are unenlightened guests and run a paravisor at VMPL0 for communicating. GHCB pages are being allocated and set up by that paravisor. Linux gets the GHCB page's physical address via MSR_AMD64_SEV_ES_GHCB from the paravisor and should not change it. Add a @set_ghcb_msr parameter to sev_es_ghcb_hv_call() to control whether the function should set the GHCB's address prior to the call or not and export that function for use by HyperV. [ bp: - Massage commit message - add a struct ghcb forward declaration to fix randconfig builds. ] Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20211025122116.264793-6-ltykernel@gmail.com
2021-10-25KVM: x86/xen: Fix kvm_xen_has_interrupt() sleeping in kvm_vcpu_block()David Woodhouse
In kvm_vcpu_block, the current task is set to TASK_INTERRUPTIBLE before making a final check whether the vCPU should be woken from HLT by any incoming interrupt. This is a problem for the get_user() in __kvm_xen_has_interrupt(), which really shouldn't be sleeping when the task state has already been set. I think it's actually harmless as it would just manifest itself as a spurious wakeup, but it's causing a debug warning: [ 230.963649] do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000b6bcdbc9>] prepare_to_swait_exclusive+0x30/0x80 Fix the warning by turning it into an *explicit* spurious wakeup. When invoked with !task_is_running(current) (and we might as well add in_atomic() there while we're at it), just return 1 to indicate that an IRQ is pending, which will cause a wakeup and then something will call it again in a context that *can* sleep so it can fault the page back in. Cc: stable@vger.kernel.org Fixes: 40da8ccd724f ("KVM: x86/xen: Add event channel interrupt vector upcall") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <168bf8c689561da904e48e2ff5ae4713eaef9e2d.camel@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25KVM: x86: switch pvclock_gtod_sync_lock to a raw spinlockDavid Woodhouse
On the preemption path when updating a Xen guest's runstate times, this lock is taken inside the scheduler rq->lock, which is a raw spinlock. This was shown in a lockdep warning: [ 89.138354] ============================= [ 89.138356] [ BUG: Invalid wait context ] [ 89.138358] 5.15.0-rc5+ #834 Tainted: G S I E [ 89.138360] ----------------------------- [ 89.138361] xen_shinfo_test/2575 is trying to lock: [ 89.138363] ffffa34a0364efd8 (&kvm->arch.pvclock_gtod_sync_lock){....}-{3:3}, at: get_kvmclock_ns+0x1f/0x130 [kvm] [ 89.138442] other info that might help us debug this: [ 89.138444] context-{5:5} [ 89.138445] 4 locks held by xen_shinfo_test/2575: [ 89.138447] #0: ffff972bdc3b8108 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x77/0x6f0 [kvm] [ 89.138483] #1: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_ioctl_run+0xdc/0x8b0 [kvm] [ 89.138526] #2: ffff97331fdbac98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0xff/0xbd0 [ 89.138534] #3: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_put+0x26/0x170 [kvm] ... [ 89.138695] get_kvmclock_ns+0x1f/0x130 [kvm] [ 89.138734] kvm_xen_update_runstate+0x14/0x90 [kvm] [ 89.138783] kvm_xen_update_runstate_guest+0x15/0xd0 [kvm] [ 89.138830] kvm_arch_vcpu_put+0xe6/0x170 [kvm] [ 89.138870] kvm_sched_out+0x2f/0x40 [kvm] [ 89.138900] __schedule+0x5de/0xbd0 Cc: stable@vger.kernel.org Reported-by: syzbot+b282b65c2c68492df769@syzkaller.appspotmail.com Fixes: 30b5c851af79 ("KVM: x86/xen: Add support for vCPU runstate information") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Message-Id: <1b02a06421c17993df337493a68ba923f3bd5c0f.camel@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25KVM: x86: SGX must obey the KVM_INTERNAL_ERROR_EMULATION protocolDavid Edmondson
When passing the failing address and size out to user space, SGX must ensure not to trample on the earlier fields of the emulation_failure sub-union of struct kvm_run. Signed-off-by: David Edmondson <david.edmondson@oracle.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210920103737.2696756-5-david.edmondson@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25KVM: x86: On emulation failure, convey the exit reason, etc. to userspaceDavid Edmondson
Should instruction emulation fail, include the VM exit reason, etc. in the emulation_failure data passed to userspace, in order that the VMM can report it as a debugging aid when describing the failure. Suggested-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: David Edmondson <david.edmondson@oracle.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210920103737.2696756-4-david.edmondson@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25KVM: x86: Get exit_reason as part of kvm_x86_ops.get_exit_infoDavid Edmondson
Extend the get_exit_info static call to provide the reason for the VM exit. Modify relevant trace points to use this rather than extracting the reason in the caller. Signed-off-by: David Edmondson <david.edmondson@oracle.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210920103737.2696756-3-david.edmondson@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-25x86/of: Kill unused early_init_dt_scan_chosen_arch()Rob Herring
There are no callers for early_init_dt_scan_chosen_arch(), so remove it. Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Link: https://lkml.kernel.org/r/20211022164642.2815706-1-robh@kernel.org
2021-10-24kbuild: use more subdir- for visiting subdirectories while cleaningMasahiro Yamada
Documentation/kbuild/makefiles.rst suggests to use "archclean" for cleaning arch/$(SRCARCH)/boot/, but it is not a hard requirement. Since commit d92cc4d51643 ("kbuild: require all architectures to have arch/$(SRCARCH)/Kbuild"), we can use the "subdir- += boot" trick for all architectures. This can take advantage of the parallel option (-j) for "make clean". I also cleaned up the comments in arch/$(SRCARCH)/Makefile. The "archdep" target no longer exists. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
2021-10-23x86/fpu: Remove old KVM FPU interfaceThomas Gleixner
No more users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211022185313.074853631@linutronix.de
2021-10-23x86/kvm: Convert FPU handling to a single swap bufferThomas Gleixner
For the upcoming AMX support it's necessary to do a proper integration with KVM. Currently KVM allocates two FPU structs which are used for saving the user state of the vCPU thread and restoring the guest state when entering vcpu_run() and doing the reverse operation before leaving vcpu_run(). With the new fpstate mechanism this can be reduced to one extra buffer by swapping the fpstate pointer in current::thread::fpu. This makes the upcoming support for AMX and XFD simpler because then fpstate information (features, sizes, xfd) are always consistent and it does not require any nasty workarounds. Convert the KVM FPU code over to this new scheme. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211022185313.019454292@linutronix.de
2021-10-23x86/fpu: Provide infrastructure for KVM FPU cleanupThomas Gleixner
For the upcoming AMX support it's necessary to do a proper integration with KVM. Currently KVM allocates two FPU structs which are used for saving the user state of the vCPU thread and restoring the guest state when entering vcpu_run() and doing the reverse operation before leaving vcpu_run(). With the new fpstate mechanism this can be reduced to one extra buffer by swapping the fpstate pointer in current::thread::fpu. This makes the upcoming support for AMX and XFD simpler because then fpstate information (features, sizes, xfd) are always consistent and it does not require any nasty workarounds. Provide: - An allocator which initializes the state properly - A replacement for the existing FPU swap mechanim Aside of the reduced memory footprint, this also makes state switching more efficient when TIF_FPU_NEED_LOAD is set. It does not require a memcpy as the state is already correct in the to be swapped out fpstate. The existing interfaces will be removed once KVM is converted over. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211022185312.954684740@linutronix.de
2021-10-23x86/fpu: Prepare for sanitizing KVM FPU codeThomas Gleixner
For the upcoming AMX support it's necessary to do a proper integration with KVM. To avoid more nasty hackery in KVM which violate encapsulation extend struct fpu and fpstate so the fpstate switching can be consolidated and simplified. Currently KVM allocates two FPU structs which are used for saving the user state of the vCPU thread and restoring the guest state when entering vcpu_run() and doing the reverse operation before leaving vcpu_run(). With the new fpstate mechanism this can be reduced to one extra buffer by swapping the fpstate pointer in current::thread::fpu. This makes the upcoming support for AMX and XFD simpler because then fpstate information (features, sizes, xfd) are always consistent and it does not require any nasty workarounds. Add fpu::__task_fpstate to save the regular fpstate pointer while the task is inside vcpu_run(). Add some state fields to fpstate to indicate the nature of the state. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211022185312.896403942@linutronix.de
2021-10-22Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull more x86 kvm fixes from Paolo Bonzini: - Cache coherency fix for SEV live migration - Fix for instruction emulation with PKU - fixes for rare delaying of interrupt delivery - fix for SEV-ES buffer overflow * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: SEV-ES: go over the sev_pio_data buffer in multiple passes if needed KVM: SEV-ES: keep INS functions together KVM: x86: remove unnecessary arguments from complete_emulator_pio_in KVM: x86: split the two parts of emulator_pio_in KVM: SEV-ES: clean up kvm_sev_es_ins/outs KVM: x86: leave vcpu->arch.pio.count alone in emulator_pio_in_out KVM: SEV-ES: rename guest_ins_data to sev_pio_data KVM: SEV: Flush cache on non-coherent systems before RECEIVE_UPDATE_DATA KVM: MMU: Reset mmu->pkru_mask to avoid stale data KVM: nVMX: promptly process interrupts delivered while in guest mode KVM: x86: check for interrupts before deciding whether to exit the fast path
2021-10-22kvm: x86: Remove stale declaration of kvm_no_apic_vcpuJim Mattson
This variable was renamed to kvm_has_noapic_vcpu in commit 6e4e3b4df4e3 ("KVM: Stop using deprecated jump label APIs"). Signed-off-by: Jim Mattson <jmattson@google.com> Message-Id: <20211021185449.3471763-1-jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: VMX: Unregister posted interrupt wakeup handler on hardware unsetupSean Christopherson
Unregister KVM's posted interrupt wakeup handler during unsetup so that a spurious interrupt that arrives after kvm_intel.ko is unloaded doesn't call into freed memory. Fixes: bf9f6ac8d749 ("KVM: Update Posted-Interrupts Descriptor when vCPU is blocked") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009001107.3936588-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22x86/irq: Ensure PI wakeup handler is unregistered before module unloadSean Christopherson
Add a synchronize_rcu() after clearing the posted interrupt wakeup handler to ensure all readers, i.e. in-flight IRQ handlers, see the new handler before returning to the caller. If the caller is an exiting module and is unregistering its handler, failure to wait could result in the IRQ handler jumping into an unloaded module. The registration path doesn't require synchronization, as it's the caller's responsibility to not generate interrupts it cares about until after its handler is registered. Fixes: f6b3c72c2366 ("x86/irq: Define a global vector for VT-d Posted-Interrupts") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009001107.3936588-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22sched,x86: Fix L2 cache maskPeter Zijlstra
Currently AMD/Hygon do not populate l2c_id, this means that for SMT enabled systems they report an L2 per thread. This is ofcourse not true but was harmless so far. However, since commit: 66558b730f25 ("sched: Add cluster scheduler level for x86") the scheduler topology setup requires: SMT <= L2 <= LLC Which leads to noisy warnings and possibly weird behaviour on affected chips. Therefore change the topology generation such that if l2c_id is not populated it follows the SMT topology, thereby satisfying the constraint. Fixes: 66558b730f25 ("sched: Add cluster scheduler level for x86") Reported-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
2021-10-22x86/unwind: Compile kretprobe fixup code only if CONFIG_KRETPROBES=yMasami Hiramatsu
Compile kretprobe related stacktrace entry recovery code and unwind_state::kr_cur field only when CONFIG_KRETPROBES=y. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-22x86/sgx/virt: implement SGX_IOC_VEPC_REMOVE ioctlPaolo Bonzini
For bare-metal SGX on real hardware, the hardware provides guarantees SGX state at reboot. For instance, all pages start out uninitialized. The vepc driver provides a similar guarantee today for freshly-opened vepc instances, but guests such as Windows expect all pages to be in uninitialized state on startup, including after every guest reboot. Some userspace implementations of virtual SGX would rather avoid having to close and reopen the /dev/sgx_vepc file descriptor and re-mmap the virtual EPC. For example, they could sandbox themselves after the guest starts and forbid further calls to open(), in order to mitigate exploits from untrusted guests. Therefore, add a ioctl that does this with EREMOVE. Userspace can invoke the ioctl to bring its vEPC pages back to uninitialized state. There is a possibility that some pages fail to be removed if they are SECS pages, and the child and SECS pages could be in separate vEPC regions. Therefore, the ioctl returns the number of EREMOVE failures, telling userspace to try the ioctl again after it's done with all vEPC regions. A more verbose description of the correct usage and the possible error conditions is documented in sgx.rst. Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20211021201155.1523989-3-pbonzini@redhat.com
2021-10-22x86/sgx/virt: extract sgx_vepc_remove_pagePaolo Bonzini
For bare-metal SGX on real hardware, the hardware provides guarantees SGX state at reboot. For instance, all pages start out uninitialized. The vepc driver provides a similar guarantee today for freshly-opened vepc instances, but guests such as Windows expect all pages to be in uninitialized state on startup, including after every guest reboot. One way to do this is to simply close and reopen the /dev/sgx_vepc file descriptor and re-mmap the virtual EPC. However, this is problematic because it prevents sandboxing the userspace (for example forbidding open() after the guest starts; this is doable with heavy use of SCM_RIGHTS file descriptor passing). In order to implement this, we will need a ioctl that performs EREMOVE on all pages mapped by a /dev/sgx_vepc file descriptor: other possibilities, such as closing and reopening the device, are racy. Start the implementation by creating a separate function with just the __eremove wrapper. Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20211021201155.1523989-2-pbonzini@redhat.com
2021-10-22KVM: x86: Use rw_semaphore for APICv lock to allow vCPU parallelismSean Christopherson
Use a rw_semaphore instead of a mutex to coordinate APICv updates so that vCPUs responding to requests can take the lock for read and run in parallel. Using a mutex forces serialization of vCPUs even though kvm_vcpu_update_apicv() only touches data local to that vCPU or is protected by a different lock, e.g. SVM's ir_list_lock. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211022004927.1448382-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86: Move SVM's APICv sanity check to common x86Sean Christopherson
Move SVM's assertion that vCPU's APICv state is consistent with its VM's state out of svm_vcpu_run() and into x86's common inner run loop. The assertion and underlying logic is not unique to SVM, it's just that SVM has more inhibiting conditions and thus is more likely to run headfirst into any KVM bugs. Add relevant comments to document exactly why the update path has unusual ordering between the update the kick, why said ordering is safe, and also the basic rules behind the assertion in the run loop. Cc: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211022004927.1448382-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: SEV-ES: go over the sev_pio_data buffer in multiple passes if neededPaolo Bonzini
The PIO scratch buffer is larger than a single page, and therefore it is not possible to copy it in a single step to vcpu->arch/pio_data. Bound each call to emulator_pio_in/out to a single page; keep track of how many I/O operations are left in vcpu->arch.sev_pio_count, so that the operation can be restarted in the complete_userspace_io callback. For OUT, this means that the previous kvm_sev_es_outs implementation becomes an iterator of the loop, and we can consume the sev_pio_data buffer before leaving to userspace. For IN, instead, consuming the buffer and decreasing sev_pio_count is always done in the complete_userspace_io callback, because that is when the memcpy is done into sev_pio_data. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reported-by: Felix Wilhelm <fwilhelm@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: SEV-ES: keep INS functions togetherPaolo Bonzini
Make the diff a little nicer when we actually get to fixing the bug. No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86: remove unnecessary arguments from complete_emulator_pio_inPaolo Bonzini
complete_emulator_pio_in can expect that vcpu->arch.pio has been filled in, and therefore does not need the size and count arguments. This makes things nicer when the function is called directly from a complete_userspace_io callback. No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86: split the two parts of emulator_pio_inPaolo Bonzini
emulator_pio_in handles both the case where the data is pending in vcpu->arch.pio.count, and the case where I/O has to be done via either an in-kernel device or a userspace exit. For SEV-ES we would like to split these, to identify clearly the moment at which the sev_pio_data is consumed. To this end, create two different functions: __emulator_pio_in fills in vcpu->arch.pio.count, while complete_emulator_pio_in clears it and releases vcpu->arch.pio.data. Because this patch has to be backported, things are left a bit messy. kernel_pio() operates on vcpu->arch.pio, which leads to emulator_pio_in() having with two calls to complete_emulator_pio_in(). It will be fixed in the next release. While at it, remove the unused void* val argument of emulator_pio_in_out. The function currently hardcodes vcpu->arch.pio_data as the source/destination buffer, which sucks but will be fixed after the more severe SEV-ES buffer overflow. No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: SEV-ES: clean up kvm_sev_es_ins/outsPaolo Bonzini
A few very small cleanups to the functions, smushed together because the patch is already very small like this: - inline emulator_pio_in_emulated and emulator_pio_out_emulated, since we already have the vCPU - remove the data argument and pull setting vcpu->arch.sev_pio_data into the caller - remove unnecessary clearing of vcpu->arch.pio.count when emulation is done by the kernel (and therefore vcpu->arch.pio.count is already clear on exit from emulator_pio_in and emulator_pio_out). No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86: leave vcpu->arch.pio.count alone in emulator_pio_in_outPaolo Bonzini
Currently emulator_pio_in clears vcpu->arch.pio.count twice if emulator_pio_in_out performs kernel PIO. Move the clear into emulator_pio_out where it is actually necessary. No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: SEV-ES: rename guest_ins_data to sev_pio_dataPaolo Bonzini
We will be using this field for OUTS emulation as well, in case the data that is pushed via OUTS spans more than one page. In that case, there will be a need to save the data pointer across exits to userspace. So, change the name to something that refers to any kind of PIO. Also spell out what it is used for, namely SEV-ES. No functional change intended. Cc: stable@vger.kernel.org Fixes: 7ed9abfe8e9f ("KVM: SVM: Support string IO operations for an SEV-ES guest") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22crypto: x86/sm4 - Fix invalid section entry sizeTianjia Zhang
This fixes the following warning: vmlinux.o: warning: objtool: elf_update: invalid section entry size The size of the rodata section is 164 bytes, directly using the entry_size of 164 bytes will cause errors in some versions of the gcc compiler, while using 16 bytes directly will cause errors in the clang compiler. This patch correct it by filling the size of rodata to a 16-byte boundary. Fixes: a7ee22ee1445 ("crypto: x86/sm4 - add AES-NI/AVX/x86_64 implementation") Fixes: 5b2efa2bb865 ("crypto: x86/sm4 - add AES-NI/AVX2/x86_64 implementation") Reported-by: Peter Zijlstra <peterz@infradead.org> Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Tested-by: Heyuan Shi <heyuan@linux.alibaba.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-10-22x86/build: Tuck away built-in firmware under FW_LOADERLuis Chamberlain
When FW_LOADER is modular or disabled we don't use it. Update x86 relocs to reflect that. Reviewed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20211021155843.1969401-7-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-22x86/microcode: Use the firmware_loader built-in APIBorislav Petkov
The microcode loader has been looping through __start_builtin_fw down to __end_builtin_fw to look for possibly built-in firmware for microcode updates. Now that the firmware loader code has exported an API for looping through the kernel's built-in firmware section, use it and drop the x86 implementation in favor. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20211021155843.1969401-4-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Lots of simnple overlapping additions. With a build fix from Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-22KVM: x86/mmu: Extract zapping of rmaps for gfn range to separate helperSean Christopherson
Extract the zapping of rmaps, a.k.a. legacy MMU, for a gfn range to a separate helper to clean up the unholy mess that kvm_zap_gfn_range() has become. In addition to deep nesting, the rmaps zapping spreads out the declaration of several variables and is generally a mess. Clean up the mess now so that future work to improve the memslots implementation doesn't need to deal with it. Cc: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211022010005.1454978-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86/mmu: Drop a redundant remote TLB flush in kvm_zap_gfn_range()Sean Christopherson
Remove an unnecessary remote TLB flush in kvm_zap_gfn_range() now that said function holds mmu_lock for write for its entire duration. The flush was added by the now-reverted commit to allow TDP MMU to flush while holding mmu_lock for read, as the transition from write=>read required dropping the lock and thus a pending flush needed to be serviced. Fixes: 5a324c24b638 ("Revert "KVM: x86/mmu: Allow zap gfn range to operate under the mmu read lock"") Cc: Maxim Levitsky <mlevitsk@redhat.com> Cc: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211022010005.1454978-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: x86/mmu: Drop a redundant, broken remote TLB flushSean Christopherson
A recent commit to fix the calls to kvm_flush_remote_tlbs_with_address() in kvm_zap_gfn_range() inadvertantly added yet another flush instead of fixing the existing flush. Drop the redundant flush, and fix the params for the existing flush. Cc: stable@vger.kernel.org Fixes: 2822da446640 ("KVM: x86/mmu: fix parameters to kvm_flush_remote_tlbs_with_address") Cc: Maxim Levitsky <mlevitsk@redhat.com> Cc: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211022010005.1454978-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-22KVM: X86: Don't unload MMU in kvm_vcpu_flush_tlb_guest()Lai Jiangshan
kvm_mmu_unload() destroys all the PGD caches. Use the lighter kvm_mmu_sync_roots() and kvm_mmu_sync_prev_roots() instead. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Message-Id: <20211019110154.4091-5-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>