From 42de7b9e216728edbe53e0c4513e06fe3d566c5d Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Mon, 10 Sep 2018 18:29:10 +1000 Subject: KVM: PPC: Validate TCEs against preregistered memory page sizes The userspace can request an arbitrary supported page size for a DMA window and this works fine as long as the mapped memory is backed with the pages of the same or bigger size; if this is not the case, mm_iommu_ua_to_hpa{_rm}() fail and tables do not populated with dangerously incorrect TCEs. However since it is quite easy to misconfigure the KVM and we do not do reverts to all changes made to TCE tables if an error happens in a middle, we better do the acceptable page size validation before we even touch the tables. This enhances kvmppc_tce_validate() to check the hardware IOMMU page sizes against the preregistered memory page sizes. Since the new check uses real/virtual mode helpers, this renames kvmppc_tce_validate() to kvmppc_rm_tce_validate() to handle the real mode case and mirrors it for the virtual mode under the old name. The real mode handler is not used for the virtual mode as: 1. it uses _lockless() list traversing primitives instead of RCU; 2. realmode's mm_iommu_ua_to_hpa_rm() uses vmalloc_to_phys() which virtual mode does not have to use and since on POWER9+radix only virtual mode handlers actually work, we do not want to slow down that path even a bit. This removes EXPORT_SYMBOL_GPL(kvmppc_tce_validate) as the validators are static now. From now on the attempts on mapping IOMMU pages bigger than allowed will result in KVM exit. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson [mpe: Fix KVM_HV=n build] Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/kvm_ppc.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index e991821dd7fa..2f5d431e438b 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -194,8 +194,6 @@ extern struct kvmppc_spapr_tce_table *kvmppc_find_table( (iommu_tce_check_ioba((stt)->page_shift, (stt)->offset, \ (stt)->size, (ioba), (npages)) ? \ H_PARAMETER : H_SUCCESS) -extern long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *tt, - unsigned long tce); extern long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa, unsigned long *ua, unsigned long **prmap); extern void kvmppc_tce_put(struct kvmppc_spapr_tce_table *tt, -- cgit v1.2.3 From a3ac077b75c5a922dcbafd7e689ee09beefae0f6 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Mon, 10 Sep 2018 18:29:12 +1000 Subject: KVM: PPC: Remove redundand permission bits removal The kvmppc_gpa_to_ua() helper itself takes care of the permission bits in the TCE and yet every single caller removes them. This changes semantics of kvmppc_gpa_to_ua() so it takes TCEs (which are GPAs + TCE permission bits) to make the callers simpler. This should cause no behavioural change. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/kvm_ppc.h | 2 +- arch/powerpc/kvm/book3s_64_vio.c | 12 ++++-------- arch/powerpc/kvm/book3s_64_vio_hv.c | 22 +++++++++------------- 3 files changed, 14 insertions(+), 22 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 2f5d431e438b..38d03282bb6a 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -194,7 +194,7 @@ extern struct kvmppc_spapr_tce_table *kvmppc_find_table( (iommu_tce_check_ioba((stt)->page_shift, (stt)->offset, \ (stt)->size, (ioba), (npages)) ? \ H_PARAMETER : H_SUCCESS) -extern long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa, +extern long kvmppc_tce_to_ua(struct kvm *kvm, unsigned long tce, unsigned long *ua, unsigned long **prmap); extern void kvmppc_tce_put(struct kvmppc_spapr_tce_table *tt, unsigned long idx, unsigned long tce); diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c index 8231b178eac6..c0c64d11cc71 100644 --- a/arch/powerpc/kvm/book3s_64_vio.c +++ b/arch/powerpc/kvm/book3s_64_vio.c @@ -378,8 +378,7 @@ static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, if (iommu_tce_check_gpa(stt->page_shift, gpa)) return H_TOO_HARD; - if (kvmppc_gpa_to_ua(stt->kvm, tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), - &ua, NULL)) + if (kvmppc_tce_to_ua(stt->kvm, tce, &ua, NULL)) return H_TOO_HARD; list_for_each_entry_rcu(stit, &stt->iommu_tables, next) { @@ -552,8 +551,7 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, idx = srcu_read_lock(&vcpu->kvm->srcu); - if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm, - tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), &ua, NULL)) { + if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) { ret = H_PARAMETER; goto unlock_exit; } @@ -614,7 +612,7 @@ long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, return ret; idx = srcu_read_lock(&vcpu->kvm->srcu); - if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL)) { + if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua, NULL)) { ret = H_TOO_HARD; goto unlock_exit; } @@ -649,9 +647,7 @@ long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, } tce = be64_to_cpu(tce); - if (kvmppc_gpa_to_ua(vcpu->kvm, - tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), - &ua, NULL)) + if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) return H_PARAMETER; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c index ae147b5c7571..ec99363fdf54 100644 --- a/arch/powerpc/kvm/book3s_64_vio_hv.c +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c @@ -111,8 +111,7 @@ static long kvmppc_rm_tce_validate(struct kvmppc_spapr_tce_table *stt, if (iommu_tce_check_gpa(stt->page_shift, gpa)) return H_PARAMETER; - if (kvmppc_gpa_to_ua(stt->kvm, tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), - &ua, NULL)) + if (kvmppc_tce_to_ua(stt->kvm, tce, &ua, NULL)) return H_TOO_HARD; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { @@ -182,10 +181,10 @@ void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt, } EXPORT_SYMBOL_GPL(kvmppc_tce_put); -long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa, +long kvmppc_tce_to_ua(struct kvm *kvm, unsigned long tce, unsigned long *ua, unsigned long **prmap) { - unsigned long gfn = gpa >> PAGE_SHIFT; + unsigned long gfn = tce >> PAGE_SHIFT; struct kvm_memory_slot *memslot; memslot = search_memslots(kvm_memslots(kvm), gfn); @@ -193,7 +192,7 @@ long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa, return -EINVAL; *ua = __gfn_to_hva_memslot(memslot, gfn) | - (gpa & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE)); + (tce & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE)); #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE if (prmap) @@ -202,7 +201,7 @@ long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa, return 0; } -EXPORT_SYMBOL_GPL(kvmppc_gpa_to_ua); +EXPORT_SYMBOL_GPL(kvmppc_tce_to_ua); #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE static long iommu_tce_xchg_rm(struct mm_struct *mm, struct iommu_table *tbl, @@ -391,8 +390,7 @@ long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, return ret; dir = iommu_tce_direction(tce); - if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm, - tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), &ua, NULL)) + if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) return H_PARAMETER; entry = ioba >> stt->page_shift; @@ -494,7 +492,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, */ struct mm_iommu_table_group_mem_t *mem; - if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL)) + if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua, NULL)) return H_TOO_HARD; mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K); @@ -510,7 +508,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, * We do not require memory to be preregistered in this case * so lock rmap and do __find_linux_pte_or_hugepte(). */ - if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, &rmap)) + if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua, &rmap)) return H_TOO_HARD; rmap = (void *) vmalloc_to_phys(rmap); @@ -544,9 +542,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu, unsigned long tce = be64_to_cpu(((u64 *)tces)[i]); ua = 0; - if (kvmppc_gpa_to_ua(vcpu->kvm, - tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), - &ua, NULL)) + if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) return H_PARAMETER; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { -- cgit v1.2.3 From f7035ce9f1dfb1042c4acedf5cca6f9af395f110 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 8 Oct 2018 16:30:50 +1100 Subject: KVM: PPC: Book3S HV: Move interrupt delivery on guest entry to C code This is based on a patch by Suraj Jitindar Singh. This moves the code in book3s_hv_rmhandlers.S that generates an external, decrementer or privileged doorbell interrupt just before entering the guest to C code in book3s_hv_builtin.c. This is to make future maintenance and modification easier. The algorithm expressed in the C code is almost identical to the previous algorithm. Reviewed-by: David Gibson Signed-off-by: Paul Mackerras Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/kvm_ppc.h | 1 + arch/powerpc/kvm/book3s_hv.c | 3 +- arch/powerpc/kvm/book3s_hv_builtin.c | 48 ++++++++++++++++++++++ arch/powerpc/kvm/book3s_hv_rmhandlers.S | 70 ++++++++------------------------- 4 files changed, 67 insertions(+), 55 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 38d03282bb6a..03a60f76f3d7 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -650,6 +650,7 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, unsigned long mfrr); int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr); int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr); +void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu); /* * Host-side operations we want to set up while running in real diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 3e3a71594e63..49a686c1185c 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -730,8 +730,7 @@ static bool kvmppc_doorbell_pending(struct kvm_vcpu *vcpu) /* * Ensure that the read of vcore->dpdes comes after the read * of vcpu->doorbell_request. This barrier matches the - * lwsync in book3s_hv_rmhandlers.S just before the - * fast_guest_return label. + * smb_wmb() in kvmppc_guest_entry_inject(). */ smp_rmb(); vc = vcpu->arch.vcore; diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index fc6bb9630a9c..ccfea5b96d89 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -729,3 +729,51 @@ void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip) smp_mb(); local_paca->kvm_hstate.kvm_split_mode = NULL; } + +/* + * Is there a PRIV_DOORBELL pending for the guest (on POWER9)? + * Can we inject a Decrementer or a External interrupt? + */ +void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu) +{ + int ext; + unsigned long vec = 0; + unsigned long lpcr; + + /* Insert EXTERNAL bit into LPCR at the MER bit position */ + ext = (vcpu->arch.pending_exceptions >> BOOK3S_IRQPRIO_EXTERNAL) & 1; + lpcr = mfspr(SPRN_LPCR); + lpcr |= ext << LPCR_MER_SH; + mtspr(SPRN_LPCR, lpcr); + isync(); + + if (vcpu->arch.shregs.msr & MSR_EE) { + if (ext) { + vec = BOOK3S_INTERRUPT_EXTERNAL; + } else { + long int dec = mfspr(SPRN_DEC); + if (!(lpcr & LPCR_LD)) + dec = (int) dec; + if (dec < 0) + vec = BOOK3S_INTERRUPT_DECREMENTER; + } + } + if (vec) { + unsigned long msr, old_msr = vcpu->arch.shregs.msr; + + kvmppc_set_srr0(vcpu, kvmppc_get_pc(vcpu)); + kvmppc_set_srr1(vcpu, old_msr); + kvmppc_set_pc(vcpu, vec); + msr = vcpu->arch.intr_msr; + if (MSR_TM_ACTIVE(old_msr)) + msr |= MSR_TS_S; + vcpu->arch.shregs.msr = msr; + } + + if (vcpu->arch.doorbell_request) { + mtspr(SPRN_DPDES, 1); + vcpu->arch.vcore->dpdes = 1; + smp_wmb(); + vcpu->arch.doorbell_request = 0; + } +} diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 77960e68f7b0..6752da132ba6 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1101,13 +1101,20 @@ no_xive: #endif /* CONFIG_KVM_XICS */ deliver_guest_interrupt: - ld r6, VCPU_CTR(r4) - ld r7, VCPU_XER(r4) - - mtctr r6 - mtxer r7 - kvmppc_cede_reentry: /* r4 = vcpu, r13 = paca */ + /* Check if we can deliver an external or decrementer interrupt now */ + ld r0, VCPU_PENDING_EXC(r4) +BEGIN_FTR_SECTION + /* On POWER9, also check for emulated doorbell interrupt */ + lbz r3, VCPU_DBELL_REQ(r4) + or r0, r0, r3 +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) + cmpdi r0, 0 + beq 71f + mr r3, r4 + bl kvmppc_guest_entry_inject_int + ld r4, HSTATE_KVM_VCPU(r13) +71: ld r10, VCPU_PC(r4) ld r11, VCPU_MSR(r4) ld r6, VCPU_SRR0(r4) @@ -1120,53 +1127,10 @@ kvmppc_cede_reentry: /* r4 = vcpu, r13 = paca */ rotldi r11, r11, 1 + MSR_HV_LG ori r11, r11, MSR_ME - /* Check if we can deliver an external or decrementer interrupt now */ - ld r0, VCPU_PENDING_EXC(r4) - rldicl r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL, 63 - cmpdi cr1, r0, 0 - andi. r8, r11, MSR_EE - mfspr r8, SPRN_LPCR - /* Insert EXTERNAL bit into LPCR at the MER bit position */ - rldimi r8, r0, LPCR_MER_SH, 63 - LPCR_MER_SH - mtspr SPRN_LPCR, r8 - isync - beq 5f - li r0, BOOK3S_INTERRUPT_EXTERNAL - bne cr1, 12f - mfspr r0, SPRN_DEC -BEGIN_FTR_SECTION - /* On POWER9 check whether the guest has large decrementer enabled */ - andis. r8, r8, LPCR_LD@h - bne 15f -END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) - extsw r0, r0 -15: cmpdi r0, 0 - li r0, BOOK3S_INTERRUPT_DECREMENTER - bge 5f - -12: mtspr SPRN_SRR0, r10 - mr r10,r0 - mtspr SPRN_SRR1, r11 - mr r9, r4 - bl kvmppc_msr_interrupt -5: -BEGIN_FTR_SECTION - b fast_guest_return -END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) - /* On POWER9, check for pending doorbell requests */ - lbz r0, VCPU_DBELL_REQ(r4) - cmpwi r0, 0 - beq fast_guest_return - ld r5, HSTATE_KVM_VCORE(r13) - /* Set DPDES register so the CPU will take a doorbell interrupt */ - li r0, 1 - mtspr SPRN_DPDES, r0 - std r0, VCORE_DPDES(r5) - /* Make sure other cpus see vcore->dpdes set before dbell req clear */ - lwsync - /* Clear the pending doorbell request */ - li r0, 0 - stb r0, VCPU_DBELL_REQ(r4) + ld r6, VCPU_CTR(r4) + ld r7, VCPU_XER(r4) + mtctr r6 + mtxer r7 /* * Required state: -- cgit v1.2.3 From 95a6432ce903858a2f285d611275340aa574c6ac Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 8 Oct 2018 16:30:55 +1100 Subject: KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests This creates an alternative guest entry/exit path which is used for radix guests on POWER9 systems when we have indep_threads_mode=Y. In these circumstances there is exactly one vcpu per vcore and there is no coordination required between vcpus or vcores; the vcpu can enter the guest without needing to synchronize with anything else. The new fast path is implemented almost entirely in C in book3s_hv.c and runs with the MMU on until the guest is entered. On guest exit we use the existing path until the point where we are committed to exiting the guest (as distinct from handling an interrupt in the low-level code and returning to the guest) and we have pulled the guest context from the XIVE. At that point we check a flag in the stack frame to see whether we came in via the old path and the new path; if we came in via the new path then we go back to C code to do the rest of the process of saving the guest context and restoring the host context. The C code is split into separate functions for handling the OS-accessible state and the hypervisor state, with the idea that the latter can be replaced by a hypercall when we implement nested virtualization. Signed-off-by: Paul Mackerras Reviewed-by: David Gibson [mpe: Fix CONFIG_ALTIVEC=n build] Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/asm-prototypes.h | 2 + arch/powerpc/include/asm/kvm_ppc.h | 2 + arch/powerpc/kvm/book3s_hv.c | 433 +++++++++++++++++++++++++++++- arch/powerpc/kvm/book3s_hv_ras.c | 2 + arch/powerpc/kvm/book3s_hv_rmhandlers.S | 95 ++++++- arch/powerpc/kvm/book3s_xive.c | 63 +++++ 6 files changed, 593 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h index 0c1a2b01512a..5c9b00cec4f2 100644 --- a/arch/powerpc/include/asm/asm-prototypes.h +++ b/arch/powerpc/include/asm/asm-prototypes.h @@ -165,4 +165,6 @@ void kvmhv_load_host_pmu(void); void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use); void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu); +int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu); + #endif /* _ASM_POWERPC_ASM_PROTOTYPES_H */ diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 03a60f76f3d7..88362ccda549 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -583,6 +583,7 @@ extern int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval); extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, bool line_status); +extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu); #else static inline int kvmppc_xive_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priority) { return -1; } @@ -605,6 +606,7 @@ static inline int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval) { retur static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, bool line_status) { return -ENODEV; } +static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { } #endif /* CONFIG_KVM_XIVE */ /* diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 0e17593ee6e3..4befa5a812fe 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3079,6 +3079,273 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) trace_kvmppc_run_core(vc, 1); } +/* + * Load up hypervisor-mode registers on P9. + */ +static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit) +{ + struct kvmppc_vcore *vc = vcpu->arch.vcore; + s64 hdec; + u64 tb, purr, spurr; + int trap; + unsigned long host_hfscr = mfspr(SPRN_HFSCR); + unsigned long host_ciabr = mfspr(SPRN_CIABR); + unsigned long host_dawr = mfspr(SPRN_DAWR); + unsigned long host_dawrx = mfspr(SPRN_DAWRX); + unsigned long host_psscr = mfspr(SPRN_PSSCR); + unsigned long host_pidr = mfspr(SPRN_PID); + + hdec = time_limit - mftb(); + if (hdec < 0) + return BOOK3S_INTERRUPT_HV_DECREMENTER; + mtspr(SPRN_HDEC, hdec); + + if (vc->tb_offset) { + u64 new_tb = mftb() + vc->tb_offset; + mtspr(SPRN_TBU40, new_tb); + tb = mftb(); + if ((tb & 0xffffff) < (new_tb & 0xffffff)) + mtspr(SPRN_TBU40, new_tb + 0x1000000); + vc->tb_offset_applied = vc->tb_offset; + } + + if (vc->pcr) + mtspr(SPRN_PCR, vc->pcr); + mtspr(SPRN_DPDES, vc->dpdes); + mtspr(SPRN_VTB, vc->vtb); + + local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR); + local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR); + mtspr(SPRN_PURR, vcpu->arch.purr); + mtspr(SPRN_SPURR, vcpu->arch.spurr); + + if (cpu_has_feature(CPU_FTR_DAWR)) { + mtspr(SPRN_DAWR, vcpu->arch.dawr); + mtspr(SPRN_DAWRX, vcpu->arch.dawrx); + } + mtspr(SPRN_CIABR, vcpu->arch.ciabr); + mtspr(SPRN_IC, vcpu->arch.ic); + mtspr(SPRN_PID, vcpu->arch.pid); + + mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC | + (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG)); + + mtspr(SPRN_HFSCR, vcpu->arch.hfscr); + + mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0); + mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1); + mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2); + mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3); + + mtspr(SPRN_AMOR, ~0UL); + + mtspr(SPRN_LPCR, vc->lpcr); + isync(); + + kvmppc_xive_push_vcpu(vcpu); + + mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0); + mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1); + + trap = __kvmhv_vcpu_entry_p9(vcpu); + + /* Advance host PURR/SPURR by the amount used by guest */ + purr = mfspr(SPRN_PURR); + spurr = mfspr(SPRN_SPURR); + mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr + + purr - vcpu->arch.purr); + mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr + + spurr - vcpu->arch.spurr); + vcpu->arch.purr = purr; + vcpu->arch.spurr = spurr; + + vcpu->arch.ic = mfspr(SPRN_IC); + vcpu->arch.pid = mfspr(SPRN_PID); + vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS; + + vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0); + vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1); + vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2); + vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3); + + mtspr(SPRN_PSSCR, host_psscr); + mtspr(SPRN_HFSCR, host_hfscr); + mtspr(SPRN_CIABR, host_ciabr); + mtspr(SPRN_DAWR, host_dawr); + mtspr(SPRN_DAWRX, host_dawrx); + mtspr(SPRN_PID, host_pidr); + + /* + * Since this is radix, do a eieio; tlbsync; ptesync sequence in + * case we interrupted the guest between a tlbie and a ptesync. + */ + asm volatile("eieio; tlbsync; ptesync"); + + mtspr(SPRN_LPID, vcpu->kvm->arch.host_lpid); /* restore host LPID */ + isync(); + + vc->dpdes = mfspr(SPRN_DPDES); + vc->vtb = mfspr(SPRN_VTB); + mtspr(SPRN_DPDES, 0); + if (vc->pcr) + mtspr(SPRN_PCR, 0); + + if (vc->tb_offset_applied) { + u64 new_tb = mftb() - vc->tb_offset_applied; + mtspr(SPRN_TBU40, new_tb); + tb = mftb(); + if ((tb & 0xffffff) < (new_tb & 0xffffff)) + mtspr(SPRN_TBU40, new_tb + 0x1000000); + vc->tb_offset_applied = 0; + } + + mtspr(SPRN_HDEC, 0x7fffffff); + mtspr(SPRN_LPCR, vcpu->kvm->arch.host_lpcr); + + return trap; +} + +/* + * Virtual-mode guest entry for POWER9 and later when the host and + * guest are both using the radix MMU. The LPIDR has already been set. + */ +int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit) +{ + struct kvmppc_vcore *vc = vcpu->arch.vcore; + unsigned long host_dscr = mfspr(SPRN_DSCR); + unsigned long host_tidr = mfspr(SPRN_TIDR); + unsigned long host_iamr = mfspr(SPRN_IAMR); + s64 dec; + u64 tb; + int trap, save_pmu; + + dec = mfspr(SPRN_DEC); + tb = mftb(); + if (dec < 512) + return BOOK3S_INTERRUPT_HV_DECREMENTER; + local_paca->kvm_hstate.dec_expires = dec + tb; + if (local_paca->kvm_hstate.dec_expires < time_limit) + time_limit = local_paca->kvm_hstate.dec_expires; + + vcpu->arch.ceded = 0; + + kvmhv_save_host_pmu(); /* saves it to PACA kvm_hstate */ + + kvmppc_subcore_enter_guest(); + + vc->entry_exit_map = 1; + vc->in_guest = 1; + + if (vcpu->arch.vpa.pinned_addr) { + struct lppaca *lp = vcpu->arch.vpa.pinned_addr; + u32 yield_count = be32_to_cpu(lp->yield_count) + 1; + lp->yield_count = cpu_to_be32(yield_count); + vcpu->arch.vpa.dirty = 1; + } + + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + kvmppc_restore_tm_hv(vcpu, vcpu->arch.shregs.msr, true); + + kvmhv_load_guest_pmu(vcpu); + + msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX); + load_fp_state(&vcpu->arch.fp); +#ifdef CONFIG_ALTIVEC + load_vr_state(&vcpu->arch.vr); +#endif + + mtspr(SPRN_DSCR, vcpu->arch.dscr); + mtspr(SPRN_IAMR, vcpu->arch.iamr); + mtspr(SPRN_PSPB, vcpu->arch.pspb); + mtspr(SPRN_FSCR, vcpu->arch.fscr); + mtspr(SPRN_TAR, vcpu->arch.tar); + mtspr(SPRN_EBBHR, vcpu->arch.ebbhr); + mtspr(SPRN_EBBRR, vcpu->arch.ebbrr); + mtspr(SPRN_BESCR, vcpu->arch.bescr); + mtspr(SPRN_WORT, vcpu->arch.wort); + mtspr(SPRN_TIDR, vcpu->arch.tid); + mtspr(SPRN_DAR, vcpu->arch.shregs.dar); + mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr); + mtspr(SPRN_AMR, vcpu->arch.amr); + mtspr(SPRN_UAMOR, vcpu->arch.uamor); + + if (!(vcpu->arch.ctrl & 1)) + mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1); + + mtspr(SPRN_DEC, vcpu->arch.dec_expires - mftb()); + + if (vcpu->arch.doorbell_request) { + vc->dpdes = 1; + smp_wmb(); + vcpu->arch.doorbell_request = 0; + } + + trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit); + + vcpu->arch.slb_max = 0; + dec = mfspr(SPRN_DEC); + tb = mftb(); + vcpu->arch.dec_expires = dec + tb; + vcpu->cpu = -1; + vcpu->arch.thread_cpu = -1; + vcpu->arch.ctrl = mfspr(SPRN_CTRLF); + + vcpu->arch.iamr = mfspr(SPRN_IAMR); + vcpu->arch.pspb = mfspr(SPRN_PSPB); + vcpu->arch.fscr = mfspr(SPRN_FSCR); + vcpu->arch.tar = mfspr(SPRN_TAR); + vcpu->arch.ebbhr = mfspr(SPRN_EBBHR); + vcpu->arch.ebbrr = mfspr(SPRN_EBBRR); + vcpu->arch.bescr = mfspr(SPRN_BESCR); + vcpu->arch.wort = mfspr(SPRN_WORT); + vcpu->arch.tid = mfspr(SPRN_TIDR); + vcpu->arch.amr = mfspr(SPRN_AMR); + vcpu->arch.uamor = mfspr(SPRN_UAMOR); + vcpu->arch.dscr = mfspr(SPRN_DSCR); + + mtspr(SPRN_PSPB, 0); + mtspr(SPRN_WORT, 0); + mtspr(SPRN_AMR, 0); + mtspr(SPRN_UAMOR, 0); + mtspr(SPRN_DSCR, host_dscr); + mtspr(SPRN_TIDR, host_tidr); + mtspr(SPRN_IAMR, host_iamr); + mtspr(SPRN_PSPB, 0); + + msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX); + store_fp_state(&vcpu->arch.fp); +#ifdef CONFIG_ALTIVEC + store_vr_state(&vcpu->arch.vr); +#endif + + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + kvmppc_save_tm_hv(vcpu, vcpu->arch.shregs.msr, true); + + save_pmu = 1; + if (vcpu->arch.vpa.pinned_addr) { + struct lppaca *lp = vcpu->arch.vpa.pinned_addr; + u32 yield_count = be32_to_cpu(lp->yield_count) + 1; + lp->yield_count = cpu_to_be32(yield_count); + vcpu->arch.vpa.dirty = 1; + save_pmu = lp->pmcregs_in_use; + } + + kvmhv_save_guest_pmu(vcpu, save_pmu); + + vc->entry_exit_map = 0x101; + vc->in_guest = 0; + + mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - mftb()); + + kvmhv_load_host_pmu(); + + kvmppc_subcore_exit_guest(); + + return trap; +} + /* * Wait for some other vcpu thread to execute us, and * wake us up when we need to handle something in the host. @@ -3405,6 +3672,167 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) return vcpu->arch.ret; } +static int kvmhv_run_single_vcpu(struct kvm_run *kvm_run, + struct kvm_vcpu *vcpu, u64 time_limit) +{ + int trap, r, pcpu, pcpu0; + int srcu_idx; + struct kvmppc_vcore *vc; + struct kvm *kvm = vcpu->kvm; + + trace_kvmppc_run_vcpu_enter(vcpu); + + kvm_run->exit_reason = 0; + vcpu->arch.ret = RESUME_GUEST; + vcpu->arch.trap = 0; + + vc = vcpu->arch.vcore; + vcpu->arch.ceded = 0; + vcpu->arch.run_task = current; + vcpu->arch.kvm_run = kvm_run; + vcpu->arch.stolen_logged = vcore_stolen_time(vc, mftb()); + vcpu->arch.state = KVMPPC_VCPU_RUNNABLE; + vcpu->arch.busy_preempt = TB_NIL; + vcpu->arch.last_inst = KVM_INST_FETCH_FAILED; + vc->runnable_threads[0] = vcpu; + vc->n_runnable = 1; + vc->runner = vcpu; + + /* See if the MMU is ready to go */ + if (!kvm->arch.mmu_ready) { + r = kvmhv_setup_mmu(vcpu); + if (r) { + kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY; + kvm_run->fail_entry. + hardware_entry_failure_reason = 0; + vcpu->arch.ret = r; + goto out; + } + } + + if (need_resched()) + cond_resched(); + + kvmppc_update_vpas(vcpu); + + init_vcore_to_run(vc); + vc->preempt_tb = TB_NIL; + + preempt_disable(); + pcpu = smp_processor_id(); + vc->pcpu = pcpu; + kvmppc_prepare_radix_vcpu(vcpu, pcpu); + + local_irq_disable(); + hard_irq_disable(); + if (signal_pending(current)) + goto sigpend; + if (lazy_irq_pending() || need_resched() || !kvm->arch.mmu_ready) + goto out; + + kvmppc_core_prepare_to_enter(vcpu); + + kvmppc_clear_host_core(pcpu); + + local_paca->kvm_hstate.tid = 0; + local_paca->kvm_hstate.napping = 0; + local_paca->kvm_hstate.kvm_split_mode = NULL; + kvmppc_start_thread(vcpu, vc); + kvmppc_create_dtl_entry(vcpu, vc); + trace_kvm_guest_enter(vcpu); + + vc->vcore_state = VCORE_RUNNING; + trace_kvmppc_run_core(vc, 0); + + mtspr(SPRN_LPID, vc->kvm->arch.lpid); + isync(); + + /* See comment above in kvmppc_run_core() about this */ + pcpu0 = pcpu; + if (cpu_has_feature(CPU_FTR_ARCH_300)) + pcpu0 &= ~0x3UL; + + if (cpumask_test_cpu(pcpu0, &kvm->arch.need_tlb_flush)) { + radix__local_flush_tlb_lpid_guest(kvm->arch.lpid); + /* Clear the bit after the TLB flush */ + cpumask_clear_cpu(pcpu0, &kvm->arch.need_tlb_flush); + } + + trace_hardirqs_on(); + guest_enter_irqoff(); + + srcu_idx = srcu_read_lock(&kvm->srcu); + + this_cpu_disable_ftrace(); + + trap = kvmhv_p9_guest_entry(vcpu, time_limit); + vcpu->arch.trap = trap; + + this_cpu_enable_ftrace(); + + srcu_read_unlock(&kvm->srcu, srcu_idx); + + mtspr(SPRN_LPID, kvm->arch.host_lpid); + isync(); + + trace_hardirqs_off(); + set_irq_happened(trap); + + kvmppc_set_host_core(pcpu); + + local_irq_enable(); + guest_exit(); + + cpumask_clear_cpu(pcpu, &kvm->arch.cpu_in_guest); + + preempt_enable(); + + /* cancel pending decrementer exception if DEC is now positive */ + if (get_tb() < vcpu->arch.dec_expires && kvmppc_core_pending_dec(vcpu)) + kvmppc_core_dequeue_dec(vcpu); + + trace_kvm_guest_exit(vcpu); + r = RESUME_GUEST; + if (trap) + r = kvmppc_handle_exit_hv(kvm_run, vcpu, current); + vcpu->arch.ret = r; + + if (is_kvmppc_resume_guest(r) && vcpu->arch.ceded && + !kvmppc_vcpu_woken(vcpu)) { + kvmppc_set_timer(vcpu); + while (vcpu->arch.ceded && !kvmppc_vcpu_woken(vcpu)) { + if (signal_pending(current)) { + vcpu->stat.signal_exits++; + kvm_run->exit_reason = KVM_EXIT_INTR; + vcpu->arch.ret = -EINTR; + break; + } + spin_lock(&vc->lock); + kvmppc_vcore_blocked(vc); + spin_unlock(&vc->lock); + } + } + vcpu->arch.ceded = 0; + + vc->vcore_state = VCORE_INACTIVE; + trace_kvmppc_run_core(vc, 1); + + done: + kvmppc_remove_runnable(vc, vcpu); + trace_kvmppc_run_vcpu_exit(vcpu, kvm_run); + + return vcpu->arch.ret; + + sigpend: + vcpu->stat.signal_exits++; + kvm_run->exit_reason = KVM_EXIT_INTR; + vcpu->arch.ret = -EINTR; + out: + local_irq_enable(); + preempt_enable(); + goto done; +} + static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) { int r; @@ -3480,7 +3908,10 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST; do { - r = kvmppc_run_vcpu(run, vcpu); + if (kvm->arch.threads_indep && kvm_is_radix(kvm)) + r = kvmhv_run_single_vcpu(run, vcpu, ~(u64)0); + else + r = kvmppc_run_vcpu(run, vcpu); if (run->exit_reason == KVM_EXIT_PAPR_HCALL && !(vcpu->arch.shregs.msr & MSR_PR)) { diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c index ee564b682f0c..0787f12c1a1b 100644 --- a/arch/powerpc/kvm/book3s_hv_ras.c +++ b/arch/powerpc/kvm/book3s_hv_ras.c @@ -177,6 +177,7 @@ void kvmppc_subcore_enter_guest(void) local_paca->sibling_subcore_state->in_guest[subcore_id] = 1; } +EXPORT_SYMBOL_GPL(kvmppc_subcore_enter_guest); void kvmppc_subcore_exit_guest(void) { @@ -187,6 +188,7 @@ void kvmppc_subcore_exit_guest(void) local_paca->sibling_subcore_state->in_guest[subcore_id] = 0; } +EXPORT_SYMBOL_GPL(kvmppc_subcore_exit_guest); static bool kvmppc_tb_resync_required(void) { diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 45dd637d6b44..ea84696b0a3c 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -47,8 +47,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) #define NAPPING_NOVCPU 2 /* Stack frame offsets for kvmppc_hv_entry */ -#define SFS 160 +#define SFS 208 #define STACK_SLOT_TRAP (SFS-4) +#define STACK_SLOT_SHORT_PATH (SFS-8) #define STACK_SLOT_TID (SFS-16) #define STACK_SLOT_PSSCR (SFS-24) #define STACK_SLOT_PID (SFS-32) @@ -57,6 +58,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) #define STACK_SLOT_DAWR (SFS-56) #define STACK_SLOT_DAWRX (SFS-64) #define STACK_SLOT_HFSCR (SFS-72) +/* the following is used by the P9 short path */ +#define STACK_SLOT_NVGPRS (SFS-152) /* 18 gprs */ /* * Call kvmppc_hv_entry in real mode. @@ -1020,6 +1023,9 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300) no_xive: #endif /* CONFIG_KVM_XICS */ + li r0, 0 + stw r0, STACK_SLOT_SHORT_PATH(r1) + deliver_guest_interrupt: /* r4 = vcpu, r13 = paca */ /* Check if we can deliver an external or decrementer interrupt now */ ld r0, VCPU_PENDING_EXC(r4) @@ -1034,13 +1040,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) bl kvmppc_guest_entry_inject_int ld r4, HSTATE_KVM_VCPU(r13) 71: - ld r10, VCPU_PC(r4) - ld r11, VCPU_MSR(r4) ld r6, VCPU_SRR0(r4) ld r7, VCPU_SRR1(r4) mtspr SPRN_SRR0, r6 mtspr SPRN_SRR1, r7 +fast_guest_entry_c: + ld r10, VCPU_PC(r4) + ld r11, VCPU_MSR(r4) /* r11 = vcpu->arch.msr & ~MSR_HV */ rldicl r11, r11, 63 - MSR_HV_LG, 1 rotldi r11, r11, 1 + MSR_HV_LG @@ -1117,6 +1124,83 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) HRFI_TO_GUEST b . +/* + * Enter the guest on a P9 or later system where we have exactly + * one vcpu per vcore and we don't need to go to real mode + * (which implies that host and guest are both using radix MMU mode). + * r3 = vcpu pointer + * Most SPRs and all the VSRs have been loaded already. + */ +_GLOBAL(__kvmhv_vcpu_entry_p9) +EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9) + mflr r0 + std r0, PPC_LR_STKOFF(r1) + stdu r1, -SFS(r1) + + li r0, 1 + stw r0, STACK_SLOT_SHORT_PATH(r1) + + std r3, HSTATE_KVM_VCPU(r13) + mfcr r4 + stw r4, SFS+8(r1) + + std r1, HSTATE_HOST_R1(r13) + + reg = 14 + .rept 18 + std reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1) + reg = reg + 1 + .endr + + reg = 14 + .rept 18 + ld reg, __VCPU_GPR(reg)(r3) + reg = reg + 1 + .endr + + mfmsr r10 + std r10, HSTATE_HOST_MSR(r13) + + mr r4, r3 + b fast_guest_entry_c +guest_exit_short_path: + + li r0, KVM_GUEST_MODE_NONE + stb r0, HSTATE_IN_GUEST(r13) + + reg = 14 + .rept 18 + std reg, __VCPU_GPR(reg)(r9) + reg = reg + 1 + .endr + + reg = 14 + .rept 18 + ld reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1) + reg = reg + 1 + .endr + + lwz r4, SFS+8(r1) + mtcr r4 + + mr r3, r12 /* trap number */ + + addi r1, r1, SFS + ld r0, PPC_LR_STKOFF(r1) + mtlr r0 + + /* If we are in real mode, do a rfid to get back to the caller */ + mfmsr r4 + andi. r5, r4, MSR_IR + bnelr + rldicl r5, r4, 64 - MSR_TS_S_LG, 62 /* extract TS field */ + mtspr SPRN_SRR0, r0 + ld r10, HSTATE_HOST_MSR(r13) + rldimi r10, r5, MSR_TS_S_LG, 63 - MSR_TS_T_LG + mtspr SPRN_SRR1, r10 + RFI_TO_KERNEL + b . + secondary_too_late: li r12, 0 stw r12, STACK_SLOT_TRAP(r1) @@ -1377,6 +1461,11 @@ guest_exit_cont: /* r9 = vcpu, r12 = trap, r13 = paca */ 1: #endif /* CONFIG_KVM_XICS */ + /* If we came in through the P9 short path, go back out to C now */ + lwz r0, STACK_SLOT_SHORT_PATH(r1) + cmpwi r0, 0 + bne guest_exit_short_path + /* For hash guest, read the guest SLB and save it away */ ld r5, VCPU_KVM(r9) lbz r0, KVM_RADIX(r5) diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index 30c2eb766954..ad4a370703d3 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -61,6 +61,69 @@ */ #define XIVE_Q_GAP 2 +/* + * Push a vcpu's context to the XIVE on guest entry. + * This assumes we are in virtual mode (MMU on) + */ +void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) +{ + void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt; + u64 pq; + + if (!tima) + return; + eieio(); + __raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS); + __raw_writel(vcpu->arch.xive_cam_word, tima + TM_QW1_OS + TM_WORD2); + vcpu->arch.xive_pushed = 1; + eieio(); + + /* + * We clear the irq_pending flag. There is a small chance of a + * race vs. the escalation interrupt happening on another + * processor setting it again, but the only consequence is to + * cause a spurious wakeup on the next H_CEDE, which is not an + * issue. + */ + vcpu->arch.irq_pending = 0; + + /* + * In single escalation mode, if the escalation interrupt is + * on, we mask it. + */ + if (vcpu->arch.xive_esc_on) { + pq = __raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr + + XIVE_ESB_SET_PQ_01)); + mb(); + + /* + * We have a possible subtle race here: The escalation + * interrupt might have fired and be on its way to the + * host queue while we mask it, and if we unmask it + * early enough (re-cede right away), there is a + * theorical possibility that it fires again, thus + * landing in the target queue more than once which is + * a big no-no. + * + * Fortunately, solving this is rather easy. If the + * above load setting PQ to 01 returns a previous + * value where P is set, then we know the escalation + * interrupt is somewhere on its way to the host. In + * that case we simply don't clear the xive_esc_on + * flag below. It will be eventually cleared by the + * handler for the escalation interrupt. + * + * Then, when doing a cede, we check that flag again + * before re-enabling the escalation interrupt, and if + * set, we abort the cede. + */ + if (!(pq & XIVE_ESB_VAL_P)) + /* Now P is 0, we can clear the flag */ + vcpu->arch.xive_esc_on = 0; + } +} +EXPORT_SYMBOL_GPL(kvmppc_xive_push_vcpu); + /* * This is a simple trigger for a generic XIVE IRQ. This must * only be called for interrupts that support a trigger page -- cgit v1.2.3 From aa069a996951f3e2e38437ef0316685a5893fc7e Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 21 Sep 2018 20:02:01 +1000 Subject: KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization With this, userspace can enable a KVM-HV guest to run nested guests under it. The administrator can control whether any nested guests can be run; setting the "nested" module parameter to false prevents any guests becoming nested hypervisors (that is, any attempt to enable the nested capability on a guest will fail). Guests which are already nested hypervisors will continue to be so. Reviewed-by: David Gibson Signed-off-by: Paul Mackerras --- Documentation/virtual/kvm/api.txt | 14 ++++++++++++++ arch/powerpc/include/asm/kvm_ppc.h | 1 + arch/powerpc/kvm/book3s_hv.c | 39 +++++++++++++++++++++++++++++--------- arch/powerpc/kvm/powerpc.c | 12 ++++++++++++ include/uapi/linux/kvm.h | 1 + 5 files changed, 58 insertions(+), 9 deletions(-) (limited to 'arch/powerpc/include/asm/kvm_ppc.h') diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 2f5f9b743bff..fde48b6708f1 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -4532,6 +4532,20 @@ With this capability, a guest may read the MSR_PLATFORM_INFO MSR. Otherwise, a #GP would be raised when the guest tries to access. Currently, this capability does not enable write permissions of this MSR for the guest. +7.16 KVM_CAP_PPC_NESTED_HV + +Architectures: ppc +Parameters: none +Returns: 0 on success, -EINVAL when the implementation doesn't support + nested-HV virtualization. + +HV-KVM on POWER9 and later systems allows for "nested-HV" +virtualization, which provides a way for a guest VM to run guests that +can run using the CPU's supervisor mode (privileged non-hypervisor +state). Enabling this capability on a VM depends on the CPU having +the necessary functionality and on the facility being enabled with a +kvm-hv module parameter. + 8. Other capabilities. ---------------------- diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 88362ccda549..9b89b1918dfc 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -325,6 +325,7 @@ struct kvmppc_ops { int (*set_smt_mode)(struct kvm *kvm, unsigned long mode, unsigned long flags); void (*giveup_ext)(struct kvm_vcpu *vcpu, ulong msr); + int (*enable_nested)(struct kvm *kvm); }; extern struct kvmppc_ops *kvmppc_hv_ops; diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index f3cdf51d0191..89bcf923d542 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -122,6 +122,16 @@ module_param_cb(h_ipi_redirect, &module_param_ops, &h_ipi_redirect, 0644); MODULE_PARM_DESC(h_ipi_redirect, "Redirect H_IPI wakeup to a free host core"); #endif +/* If set, guests are allowed to create and control nested guests */ +static bool nested = true; +module_param(nested, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(nested, "Enable nested virtualization (only on POWER9)"); + +static inline bool nesting_enabled(struct kvm *kvm) +{ + return kvm->arch.nested_enable && kvm_is_radix(kvm); +} + /* If set, the threads on each CPU core have to be in the same MMU mode */ static bool no_mixing_hpt_and_radix; @@ -963,12 +973,12 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) case H_SET_PARTITION_TABLE: ret = H_FUNCTION; - if (vcpu->kvm->arch.nested_enable) + if (nesting_enabled(vcpu->kvm)) ret = kvmhv_set_partition_table(vcpu); break; case H_ENTER_NESTED: ret = H_FUNCTION; - if (!vcpu->kvm->arch.nested_enable) + if (!nesting_enabled(vcpu->kvm)) break; ret = kvmhv_enter_nested_guest(vcpu); if (ret == H_INTERRUPT) { @@ -978,9 +988,8 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) break; case H_TLB_INVALIDATE: ret = H_FUNCTION; - if (!vcpu->kvm->arch.nested_enable) - break; - ret = kvmhv_do_nested_tlbie(vcpu); + if (nesting_enabled(vcpu->kvm)) + ret = kvmhv_do_nested_tlbie(vcpu); break; default: @@ -4508,10 +4517,8 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu) /* Must be called with kvm->lock held and mmu_ready = 0 and no vcpus running */ int kvmppc_switch_mmu_to_hpt(struct kvm *kvm) { - if (kvm->arch.nested_enable) { - kvm->arch.nested_enable = false; + if (nesting_enabled(kvm)) kvmhv_release_all_nested(kvm); - } kvmppc_free_radix(kvm); kvmppc_update_lpcr(kvm, LPCR_VPM1, LPCR_VPM1 | LPCR_UPRT | LPCR_GTSE | LPCR_HR); @@ -4788,7 +4795,7 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm) /* Perform global invalidation and return lpid to the pool */ if (cpu_has_feature(CPU_FTR_ARCH_300)) { - if (kvm->arch.nested_enable) + if (nesting_enabled(kvm)) kvmhv_release_all_nested(kvm); kvm->arch.process_table = 0; kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0); @@ -5181,6 +5188,19 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) return err; } +static int kvmhv_enable_nested(struct kvm *kvm) +{ + if (!nested) + return -EPERM; + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + return -ENODEV; + + /* kvm == NULL means the caller is testing if the capability exists */ + if (kvm) + kvm->arch.nested_enable = true; + return 0; +} + static struct kvmppc_ops kvm_ops_hv = { .get_sregs = kvm_arch_vcpu_ioctl_get_sregs_hv, .set_sregs = kvm_arch_vcpu_ioctl_set_sregs_hv, @@ -5220,6 +5240,7 @@ static struct kvmppc_ops kvm_ops_hv = { .configure_mmu = kvmhv_configure_mmu, .get_rmmu_info = kvmhv_get_rmmu_info, .set_smt_mode = kvmhv_set_smt_mode, + .enable_nested = kvmhv_enable_nested, }; static int kvm_init_subcore_bitmap(void) diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 1f4b128894a0..2869a299c4ed 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -597,6 +597,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = !!(hv_enabled && cpu_has_feature(CPU_FTR_ARCH_300) && cpu_has_feature(CPU_FTR_HVMODE)); break; + case KVM_CAP_PPC_NESTED_HV: + r = !!(hv_enabled && kvmppc_hv_ops->enable_nested && + !kvmppc_hv_ops->enable_nested(NULL)); + break; #endif case KVM_CAP_SYNC_MMU: #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE @@ -2115,6 +2119,14 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, r = kvm->arch.kvm_ops->set_smt_mode(kvm, mode, flags); break; } + + case KVM_CAP_PPC_NESTED_HV: + r = -EINVAL; + if (!is_kvmppc_hv_enabled(kvm) || + !kvm->arch.kvm_ops->enable_nested) + break; + r = kvm->arch.kvm_ops->enable_nested(kvm); + break; #endif default: r = -EINVAL; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 251be353f950..d9cec6b5cb37 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -953,6 +953,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_NESTED_STATE 157 #define KVM_CAP_ARM_INJECT_SERROR_ESR 158 #define KVM_CAP_MSR_PLATFORM_INFO 159 +#define KVM_CAP_PPC_NESTED_HV 160 #ifdef KVM_CAP_IRQ_ROUTING -- cgit v1.2.3