| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright © 2019 Oracle and/or its affiliates. All rights reserved. |
| * Copyright © 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| * |
| * KVM Xen emulation |
| */ |
| |
| #include "x86.h" |
| #include "xen.h" |
| #include "hyperv.h" |
| |
| #include <linux/kvm_host.h> |
| #include <linux/sched/stat.h> |
| |
| #include <trace/events/kvm.h> |
| #include <xen/interface/xen.h> |
| #include <xen/interface/vcpu.h> |
| |
| #include "trace.h" |
| |
| DEFINE_STATIC_KEY_DEFERRED_FALSE(kvm_xen_enabled, HZ); |
| |
| static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn) |
| { |
| gpa_t gpa = gfn_to_gpa(gfn); |
| int wc_ofs, sec_hi_ofs; |
| int ret = 0; |
| int idx = srcu_read_lock(&kvm->srcu); |
| |
| if (kvm_is_error_hva(gfn_to_hva(kvm, gfn))) { |
| ret = -EFAULT; |
| goto out; |
| } |
| kvm->arch.xen.shinfo_gfn = gfn; |
| |
| /* Paranoia checks on the 32-bit struct layout */ |
| BUILD_BUG_ON(offsetof(struct compat_shared_info, wc) != 0x900); |
| BUILD_BUG_ON(offsetof(struct compat_shared_info, arch.wc_sec_hi) != 0x924); |
| BUILD_BUG_ON(offsetof(struct pvclock_vcpu_time_info, version) != 0); |
| |
| /* 32-bit location by default */ |
| wc_ofs = offsetof(struct compat_shared_info, wc); |
| sec_hi_ofs = offsetof(struct compat_shared_info, arch.wc_sec_hi); |
| |
| #ifdef CONFIG_X86_64 |
| /* Paranoia checks on the 64-bit struct layout */ |
| BUILD_BUG_ON(offsetof(struct shared_info, wc) != 0xc00); |
| BUILD_BUG_ON(offsetof(struct shared_info, wc_sec_hi) != 0xc0c); |
| |
| if (kvm->arch.xen.long_mode) { |
| wc_ofs = offsetof(struct shared_info, wc); |
| sec_hi_ofs = offsetof(struct shared_info, wc_sec_hi); |
| } |
| #endif |
| |
| kvm_write_wall_clock(kvm, gpa + wc_ofs, sec_hi_ofs - wc_ofs); |
| kvm_make_all_cpus_request(kvm, KVM_REQ_MASTERCLOCK_UPDATE); |
| |
| out: |
| srcu_read_unlock(&kvm->srcu, idx); |
| return ret; |
| } |
| |
| static void kvm_xen_update_runstate(struct kvm_vcpu *v, int state) |
| { |
| struct kvm_vcpu_xen *vx = &v->arch.xen; |
| u64 now = get_kvmclock_ns(v->kvm); |
| u64 delta_ns = now - vx->runstate_entry_time; |
| u64 run_delay = current->sched_info.run_delay; |
| |
| if (unlikely(!vx->runstate_entry_time)) |
| vx->current_runstate = RUNSTATE_offline; |
| |
| /* |
| * Time waiting for the scheduler isn't "stolen" if the |
| * vCPU wasn't running anyway. |
| */ |
| if (vx->current_runstate == RUNSTATE_running) { |
| u64 steal_ns = run_delay - vx->last_steal; |
| |
| delta_ns -= steal_ns; |
| |
| vx->runstate_times[RUNSTATE_runnable] += steal_ns; |
| } |
| vx->last_steal = run_delay; |
| |
| vx->runstate_times[vx->current_runstate] += delta_ns; |
| vx->current_runstate = state; |
| vx->runstate_entry_time = now; |
| } |
| |
| void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, int state) |
| { |
| struct kvm_vcpu_xen *vx = &v->arch.xen; |
| struct gfn_to_hva_cache *ghc = &vx->runstate_cache; |
| struct kvm_memslots *slots = kvm_memslots(v->kvm); |
| bool atomic = (state == RUNSTATE_runnable); |
| uint64_t state_entry_time; |
| int __user *user_state; |
| uint64_t __user *user_times; |
| |
| kvm_xen_update_runstate(v, state); |
| |
| if (!vx->runstate_set) |
| return; |
| |
| if (unlikely(slots->generation != ghc->generation || kvm_is_error_hva(ghc->hva)) && |
| kvm_gfn_to_hva_cache_init(v->kvm, ghc, ghc->gpa, ghc->len)) |
| return; |
| |
| /* We made sure it fits in a single page */ |
| BUG_ON(!ghc->memslot); |
| |
| if (atomic) |
| pagefault_disable(); |
| |
| /* |
| * The only difference between 32-bit and 64-bit versions of the |
| * runstate struct us the alignment of uint64_t in 32-bit, which |
| * means that the 64-bit version has an additional 4 bytes of |
| * padding after the first field 'state'. |
| * |
| * So we use 'int __user *user_state' to point to the state field, |
| * and 'uint64_t __user *user_times' for runstate_entry_time. So |
| * the actual array of time[] in each state starts at user_times[1]. |
| */ |
| BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state) != 0); |
| BUILD_BUG_ON(offsetof(struct compat_vcpu_runstate_info, state) != 0); |
| user_state = (int __user *)ghc->hva; |
| |
| BUILD_BUG_ON(sizeof(struct compat_vcpu_runstate_info) != 0x2c); |
| |
| user_times = (uint64_t __user *)(ghc->hva + |
| offsetof(struct compat_vcpu_runstate_info, |
| state_entry_time)); |
| #ifdef CONFIG_X86_64 |
| BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state_entry_time) != |
| offsetof(struct compat_vcpu_runstate_info, state_entry_time) + 4); |
| BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, time) != |
| offsetof(struct compat_vcpu_runstate_info, time) + 4); |
| |
| if (v->kvm->arch.xen.long_mode) |
| user_times = (uint64_t __user *)(ghc->hva + |
| offsetof(struct vcpu_runstate_info, |
| state_entry_time)); |
| #endif |
| /* |
| * First write the updated state_entry_time at the appropriate |
| * location determined by 'offset'. |
| */ |
| state_entry_time = vx->runstate_entry_time; |
| state_entry_time |= XEN_RUNSTATE_UPDATE; |
| |
| BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->state_entry_time) != |
| sizeof(state_entry_time)); |
| BUILD_BUG_ON(sizeof(((struct compat_vcpu_runstate_info *)0)->state_entry_time) != |
| sizeof(state_entry_time)); |
| |
| if (__put_user(state_entry_time, user_times)) |
| goto out; |
| smp_wmb(); |
| |
| /* |
| * Next, write the new runstate. This is in the *same* place |
| * for 32-bit and 64-bit guests, asserted here for paranoia. |
| */ |
| BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state) != |
| offsetof(struct compat_vcpu_runstate_info, state)); |
| BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->state) != |
| sizeof(vx->current_runstate)); |
| BUILD_BUG_ON(sizeof(((struct compat_vcpu_runstate_info *)0)->state) != |
| sizeof(vx->current_runstate)); |
| |
| if (__put_user(vx->current_runstate, user_state)) |
| goto out; |
| |
| /* |
| * Write the actual runstate times immediately after the |
| * runstate_entry_time. |
| */ |
| BUILD_BUG_ON(offsetof(struct vcpu_runstate_info, state_entry_time) != |
| offsetof(struct vcpu_runstate_info, time) - sizeof(u64)); |
| BUILD_BUG_ON(offsetof(struct compat_vcpu_runstate_info, state_entry_time) != |
| offsetof(struct compat_vcpu_runstate_info, time) - sizeof(u64)); |
| BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->time) != |
| sizeof(((struct compat_vcpu_runstate_info *)0)->time)); |
| BUILD_BUG_ON(sizeof(((struct vcpu_runstate_info *)0)->time) != |
| sizeof(vx->runstate_times)); |
| |
| if (__copy_to_user(user_times + 1, vx->runstate_times, sizeof(vx->runstate_times))) |
| goto out; |
| smp_wmb(); |
| |
| /* |
| * Finally, clear the XEN_RUNSTATE_UPDATE bit in the guest's |
| * runstate_entry_time field. |
| */ |
| state_entry_time &= ~XEN_RUNSTATE_UPDATE; |
| __put_user(state_entry_time, user_times); |
| smp_wmb(); |
| |
| out: |
| mark_page_dirty_in_slot(v->kvm, ghc->memslot, ghc->gpa >> PAGE_SHIFT); |
| |
| if (atomic) |
| pagefault_enable(); |
| } |
| |
| int __kvm_xen_has_interrupt(struct kvm_vcpu *v) |
| { |
| int err; |
| u8 rc = 0; |
| |
| /* |
| * If the global upcall vector (HVMIRQ_callback_vector) is set and |
| * the vCPU's evtchn_upcall_pending flag is set, the IRQ is pending. |
| */ |
| struct gfn_to_hva_cache *ghc = &v->arch.xen.vcpu_info_cache; |
| struct kvm_memslots *slots = kvm_memslots(v->kvm); |
| unsigned int offset = offsetof(struct vcpu_info, evtchn_upcall_pending); |
| |
| /* No need for compat handling here */ |
| BUILD_BUG_ON(offsetof(struct vcpu_info, evtchn_upcall_pending) != |
| offsetof(struct compat_vcpu_info, evtchn_upcall_pending)); |
| BUILD_BUG_ON(sizeof(rc) != |
| sizeof(((struct vcpu_info *)0)->evtchn_upcall_pending)); |
| BUILD_BUG_ON(sizeof(rc) != |
| sizeof(((struct compat_vcpu_info *)0)->evtchn_upcall_pending)); |
| |
| /* |
| * For efficiency, this mirrors the checks for using the valid |
| * cache in kvm_read_guest_offset_cached(), but just uses |
| * __get_user() instead. And falls back to the slow path. |
| */ |
| if (likely(slots->generation == ghc->generation && |
| !kvm_is_error_hva(ghc->hva) && ghc->memslot)) { |
| /* Fast path */ |
| pagefault_disable(); |
| err = __get_user(rc, (u8 __user *)ghc->hva + offset); |
| pagefault_enable(); |
| if (!err) |
| return rc; |
| } |
| |
| /* Slow path */ |
| |
| /* |
| * This function gets called from kvm_vcpu_block() after setting the |
| * task to TASK_INTERRUPTIBLE, to see if it needs to wake immediately |
| * from a HLT. So we really mustn't sleep. If the page ended up absent |
| * at that point, just return 1 in order to trigger an immediate wake, |
| * and we'll end up getting called again from a context where we *can* |
| * fault in the page and wait for it. |
| */ |
| if (in_atomic() || !task_is_running(current)) |
| return 1; |
| |
| kvm_read_guest_offset_cached(v->kvm, ghc, &rc, offset, |
| sizeof(rc)); |
| |
| return rc; |
| } |
| |
| int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) |
| { |
| int r = -ENOENT; |
| |
| mutex_lock(&kvm->lock); |
| |
| switch (data->type) { |
| case KVM_XEN_ATTR_TYPE_LONG_MODE: |
| if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode) { |
| r = -EINVAL; |
| } else { |
| kvm->arch.xen.long_mode = !!data->u.long_mode; |
| r = 0; |
| } |
| break; |
| |
| case KVM_XEN_ATTR_TYPE_SHARED_INFO: |
| if (data->u.shared_info.gfn == GPA_INVALID) { |
| kvm->arch.xen.shinfo_gfn = GPA_INVALID; |
| r = 0; |
| break; |
| } |
| r = kvm_xen_shared_info_init(kvm, data->u.shared_info.gfn); |
| break; |
| |
| |
| case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR: |
| if (data->u.vector && data->u.vector < 0x10) |
| r = -EINVAL; |
| else { |
| kvm->arch.xen.upcall_vector = data->u.vector; |
| r = 0; |
| } |
| break; |
| |
| default: |
| break; |
| } |
| |
| mutex_unlock(&kvm->lock); |
| return r; |
| } |
| |
| int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) |
| { |
| int r = -ENOENT; |
| |
| mutex_lock(&kvm->lock); |
| |
| switch (data->type) { |
| case KVM_XEN_ATTR_TYPE_LONG_MODE: |
| data->u.long_mode = kvm->arch.xen.long_mode; |
| r = 0; |
| break; |
| |
| case KVM_XEN_ATTR_TYPE_SHARED_INFO: |
| data->u.shared_info.gfn = kvm->arch.xen.shinfo_gfn; |
| r = 0; |
| break; |
| |
| case KVM_XEN_ATTR_TYPE_UPCALL_VECTOR: |
| data->u.vector = kvm->arch.xen.upcall_vector; |
| r = 0; |
| break; |
| |
| default: |
| break; |
| } |
| |
| mutex_unlock(&kvm->lock); |
| return r; |
| } |
| |
| int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data) |
| { |
| int idx, r = -ENOENT; |
| |
| mutex_lock(&vcpu->kvm->lock); |
| idx = srcu_read_lock(&vcpu->kvm->srcu); |
| |
| switch (data->type) { |
| case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO: |
| /* No compat necessary here. */ |
| BUILD_BUG_ON(sizeof(struct vcpu_info) != |
| sizeof(struct compat_vcpu_info)); |
| BUILD_BUG_ON(offsetof(struct vcpu_info, time) != |
| offsetof(struct compat_vcpu_info, time)); |
| |
| if (data->u.gpa == GPA_INVALID) { |
| vcpu->arch.xen.vcpu_info_set = false; |
| r = 0; |
| break; |
| } |
| |
| /* It must fit within a single page */ |
| if ((data->u.gpa & ~PAGE_MASK) + sizeof(struct vcpu_info) > PAGE_SIZE) { |
| r = -EINVAL; |
| break; |
| } |
| |
| r = kvm_gfn_to_hva_cache_init(vcpu->kvm, |
| &vcpu->arch.xen.vcpu_info_cache, |
| data->u.gpa, |
| sizeof(struct vcpu_info)); |
| if (!r) { |
| vcpu->arch.xen.vcpu_info_set = true; |
| kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); |
| } |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO: |
| if (data->u.gpa == GPA_INVALID) { |
| vcpu->arch.xen.vcpu_time_info_set = false; |
| r = 0; |
| break; |
| } |
| |
| /* It must fit within a single page */ |
| if ((data->u.gpa & ~PAGE_MASK) + sizeof(struct pvclock_vcpu_time_info) > PAGE_SIZE) { |
| r = -EINVAL; |
| break; |
| } |
| |
| r = kvm_gfn_to_hva_cache_init(vcpu->kvm, |
| &vcpu->arch.xen.vcpu_time_info_cache, |
| data->u.gpa, |
| sizeof(struct pvclock_vcpu_time_info)); |
| if (!r) { |
| vcpu->arch.xen.vcpu_time_info_set = true; |
| kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); |
| } |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| if (data->u.gpa == GPA_INVALID) { |
| vcpu->arch.xen.runstate_set = false; |
| r = 0; |
| break; |
| } |
| |
| /* It must fit within a single page */ |
| if ((data->u.gpa & ~PAGE_MASK) + sizeof(struct vcpu_runstate_info) > PAGE_SIZE) { |
| r = -EINVAL; |
| break; |
| } |
| |
| r = kvm_gfn_to_hva_cache_init(vcpu->kvm, |
| &vcpu->arch.xen.runstate_cache, |
| data->u.gpa, |
| sizeof(struct vcpu_runstate_info)); |
| if (!r) { |
| vcpu->arch.xen.runstate_set = true; |
| } |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| if (data->u.runstate.state > RUNSTATE_offline) { |
| r = -EINVAL; |
| break; |
| } |
| |
| kvm_xen_update_runstate(vcpu, data->u.runstate.state); |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| if (data->u.runstate.state > RUNSTATE_offline) { |
| r = -EINVAL; |
| break; |
| } |
| if (data->u.runstate.state_entry_time != |
| (data->u.runstate.time_running + |
| data->u.runstate.time_runnable + |
| data->u.runstate.time_blocked + |
| data->u.runstate.time_offline)) { |
| r = -EINVAL; |
| break; |
| } |
| if (get_kvmclock_ns(vcpu->kvm) < |
| data->u.runstate.state_entry_time) { |
| r = -EINVAL; |
| break; |
| } |
| |
| vcpu->arch.xen.current_runstate = data->u.runstate.state; |
| vcpu->arch.xen.runstate_entry_time = |
| data->u.runstate.state_entry_time; |
| vcpu->arch.xen.runstate_times[RUNSTATE_running] = |
| data->u.runstate.time_running; |
| vcpu->arch.xen.runstate_times[RUNSTATE_runnable] = |
| data->u.runstate.time_runnable; |
| vcpu->arch.xen.runstate_times[RUNSTATE_blocked] = |
| data->u.runstate.time_blocked; |
| vcpu->arch.xen.runstate_times[RUNSTATE_offline] = |
| data->u.runstate.time_offline; |
| vcpu->arch.xen.last_steal = current->sched_info.run_delay; |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| if (data->u.runstate.state > RUNSTATE_offline && |
| data->u.runstate.state != (u64)-1) { |
| r = -EINVAL; |
| break; |
| } |
| /* The adjustment must add up */ |
| if (data->u.runstate.state_entry_time != |
| (data->u.runstate.time_running + |
| data->u.runstate.time_runnable + |
| data->u.runstate.time_blocked + |
| data->u.runstate.time_offline)) { |
| r = -EINVAL; |
| break; |
| } |
| |
| if (get_kvmclock_ns(vcpu->kvm) < |
| (vcpu->arch.xen.runstate_entry_time + |
| data->u.runstate.state_entry_time)) { |
| r = -EINVAL; |
| break; |
| } |
| |
| vcpu->arch.xen.runstate_entry_time += |
| data->u.runstate.state_entry_time; |
| vcpu->arch.xen.runstate_times[RUNSTATE_running] += |
| data->u.runstate.time_running; |
| vcpu->arch.xen.runstate_times[RUNSTATE_runnable] += |
| data->u.runstate.time_runnable; |
| vcpu->arch.xen.runstate_times[RUNSTATE_blocked] += |
| data->u.runstate.time_blocked; |
| vcpu->arch.xen.runstate_times[RUNSTATE_offline] += |
| data->u.runstate.time_offline; |
| |
| if (data->u.runstate.state <= RUNSTATE_offline) |
| kvm_xen_update_runstate(vcpu, data->u.runstate.state); |
| r = 0; |
| break; |
| |
| default: |
| break; |
| } |
| |
| srcu_read_unlock(&vcpu->kvm->srcu, idx); |
| mutex_unlock(&vcpu->kvm->lock); |
| return r; |
| } |
| |
| int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data) |
| { |
| int r = -ENOENT; |
| |
| mutex_lock(&vcpu->kvm->lock); |
| |
| switch (data->type) { |
| case KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO: |
| if (vcpu->arch.xen.vcpu_info_set) |
| data->u.gpa = vcpu->arch.xen.vcpu_info_cache.gpa; |
| else |
| data->u.gpa = GPA_INVALID; |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO: |
| if (vcpu->arch.xen.vcpu_time_info_set) |
| data->u.gpa = vcpu->arch.xen.vcpu_time_info_cache.gpa; |
| else |
| data->u.gpa = GPA_INVALID; |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| if (vcpu->arch.xen.runstate_set) { |
| data->u.gpa = vcpu->arch.xen.runstate_cache.gpa; |
| r = 0; |
| } |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| data->u.runstate.state = vcpu->arch.xen.current_runstate; |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA: |
| if (!sched_info_on()) { |
| r = -EOPNOTSUPP; |
| break; |
| } |
| data->u.runstate.state = vcpu->arch.xen.current_runstate; |
| data->u.runstate.state_entry_time = |
| vcpu->arch.xen.runstate_entry_time; |
| data->u.runstate.time_running = |
| vcpu->arch.xen.runstate_times[RUNSTATE_running]; |
| data->u.runstate.time_runnable = |
| vcpu->arch.xen.runstate_times[RUNSTATE_runnable]; |
| data->u.runstate.time_blocked = |
| vcpu->arch.xen.runstate_times[RUNSTATE_blocked]; |
| data->u.runstate.time_offline = |
| vcpu->arch.xen.runstate_times[RUNSTATE_offline]; |
| r = 0; |
| break; |
| |
| case KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST: |
| r = -EINVAL; |
| break; |
| |
| default: |
| break; |
| } |
| |
| mutex_unlock(&vcpu->kvm->lock); |
| return r; |
| } |
| |
| int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data) |
| { |
| struct kvm *kvm = vcpu->kvm; |
| u32 page_num = data & ~PAGE_MASK; |
| u64 page_addr = data & PAGE_MASK; |
| bool lm = is_long_mode(vcpu); |
| |
| /* Latch long_mode for shared_info pages etc. */ |
| vcpu->kvm->arch.xen.long_mode = lm; |
| |
| /* |
| * If Xen hypercall intercept is enabled, fill the hypercall |
| * page with VMCALL/VMMCALL instructions since that's what |
| * we catch. Else the VMM has provided the hypercall pages |
| * with instructions of its own choosing, so use those. |
| */ |
| if (kvm_xen_hypercall_enabled(kvm)) { |
| u8 instructions[32]; |
| int i; |
| |
| if (page_num) |
| return 1; |
| |
| /* mov imm32, %eax */ |
| instructions[0] = 0xb8; |
| |
| /* vmcall / vmmcall */ |
| kvm_x86_ops.patch_hypercall(vcpu, instructions + 5); |
| |
| /* ret */ |
| instructions[8] = 0xc3; |
| |
| /* int3 to pad */ |
| memset(instructions + 9, 0xcc, sizeof(instructions) - 9); |
| |
| for (i = 0; i < PAGE_SIZE / sizeof(instructions); i++) { |
| *(u32 *)&instructions[1] = i; |
| if (kvm_vcpu_write_guest(vcpu, |
| page_addr + (i * sizeof(instructions)), |
| instructions, sizeof(instructions))) |
| return 1; |
| } |
| } else { |
| /* |
| * Note, truncation is a non-issue as 'lm' is guaranteed to be |
| * false for a 32-bit kernel, i.e. when hva_t is only 4 bytes. |
| */ |
| hva_t blob_addr = lm ? kvm->arch.xen_hvm_config.blob_addr_64 |
| : kvm->arch.xen_hvm_config.blob_addr_32; |
| u8 blob_size = lm ? kvm->arch.xen_hvm_config.blob_size_64 |
| : kvm->arch.xen_hvm_config.blob_size_32; |
| u8 *page; |
| |
| if (page_num >= blob_size) |
| return 1; |
| |
| blob_addr += page_num * PAGE_SIZE; |
| |
| page = memdup_user((u8 __user *)blob_addr, PAGE_SIZE); |
| if (IS_ERR(page)) |
| return PTR_ERR(page); |
| |
| if (kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE)) { |
| kfree(page); |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| int kvm_xen_hvm_config(struct kvm *kvm, struct kvm_xen_hvm_config *xhc) |
| { |
| if (xhc->flags & ~KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL) |
| return -EINVAL; |
| |
| /* |
| * With hypercall interception the kernel generates its own |
| * hypercall page so it must not be provided. |
| */ |
| if ((xhc->flags & KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL) && |
| (xhc->blob_addr_32 || xhc->blob_addr_64 || |
| xhc->blob_size_32 || xhc->blob_size_64)) |
| return -EINVAL; |
| |
| mutex_lock(&kvm->lock); |
| |
| if (xhc->msr && !kvm->arch.xen_hvm_config.msr) |
| static_branch_inc(&kvm_xen_enabled.key); |
| else if (!xhc->msr && kvm->arch.xen_hvm_config.msr) |
| static_branch_slow_dec_deferred(&kvm_xen_enabled); |
| |
| memcpy(&kvm->arch.xen_hvm_config, xhc, sizeof(*xhc)); |
| |
| mutex_unlock(&kvm->lock); |
| return 0; |
| } |
| |
| void kvm_xen_init_vm(struct kvm *kvm) |
| { |
| kvm->arch.xen.shinfo_gfn = GPA_INVALID; |
| } |
| |
| void kvm_xen_destroy_vm(struct kvm *kvm) |
| { |
| if (kvm->arch.xen_hvm_config.msr) |
| static_branch_slow_dec_deferred(&kvm_xen_enabled); |
| } |
| |
| static int kvm_xen_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result) |
| { |
| kvm_rax_write(vcpu, result); |
| return kvm_skip_emulated_instruction(vcpu); |
| } |
| |
| static int kvm_xen_hypercall_complete_userspace(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_run *run = vcpu->run; |
| |
| if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.xen.hypercall_rip))) |
| return 1; |
| |
| return kvm_xen_hypercall_set_result(vcpu, run->xen.u.hcall.result); |
| } |
| |
| int kvm_xen_hypercall(struct kvm_vcpu *vcpu) |
| { |
| bool longmode; |
| u64 input, params[6]; |
| |
| input = (u64)kvm_register_read(vcpu, VCPU_REGS_RAX); |
| |
| /* Hyper-V hypercalls get bit 31 set in EAX */ |
| if ((input & 0x80000000) && |
| kvm_hv_hypercall_enabled(vcpu)) |
| return kvm_hv_hypercall(vcpu); |
| |
| longmode = is_64_bit_hypercall(vcpu); |
| if (!longmode) { |
| params[0] = (u32)kvm_rbx_read(vcpu); |
| params[1] = (u32)kvm_rcx_read(vcpu); |
| params[2] = (u32)kvm_rdx_read(vcpu); |
| params[3] = (u32)kvm_rsi_read(vcpu); |
| params[4] = (u32)kvm_rdi_read(vcpu); |
| params[5] = (u32)kvm_rbp_read(vcpu); |
| } |
| #ifdef CONFIG_X86_64 |
| else { |
| params[0] = (u64)kvm_rdi_read(vcpu); |
| params[1] = (u64)kvm_rsi_read(vcpu); |
| params[2] = (u64)kvm_rdx_read(vcpu); |
| params[3] = (u64)kvm_r10_read(vcpu); |
| params[4] = (u64)kvm_r8_read(vcpu); |
| params[5] = (u64)kvm_r9_read(vcpu); |
| } |
| #endif |
| trace_kvm_xen_hypercall(input, params[0], params[1], params[2], |
| params[3], params[4], params[5]); |
| |
| vcpu->run->exit_reason = KVM_EXIT_XEN; |
| vcpu->run->xen.type = KVM_EXIT_XEN_HCALL; |
| vcpu->run->xen.u.hcall.longmode = longmode; |
| vcpu->run->xen.u.hcall.cpl = kvm_x86_ops.get_cpl(vcpu); |
| vcpu->run->xen.u.hcall.input = input; |
| vcpu->run->xen.u.hcall.params[0] = params[0]; |
| vcpu->run->xen.u.hcall.params[1] = params[1]; |
| vcpu->run->xen.u.hcall.params[2] = params[2]; |
| vcpu->run->xen.u.hcall.params[3] = params[3]; |
| vcpu->run->xen.u.hcall.params[4] = params[4]; |
| vcpu->run->xen.u.hcall.params[5] = params[5]; |
| vcpu->arch.xen.hypercall_rip = kvm_get_linear_rip(vcpu); |
| vcpu->arch.complete_userspace_io = |
| kvm_xen_hypercall_complete_userspace; |
| |
| return 0; |
| } |