From patchwork Fri Jun 27 22:49:06 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mihai Caraman X-Patchwork-Id: 365200 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id B99D81400E1 for ; Sat, 28 Jun 2014 08:49:42 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753887AbaF0Wtm (ORCPT ); Fri, 27 Jun 2014 18:49:42 -0400 Received: from mail-bl2lp0204.outbound.protection.outlook.com ([207.46.163.204]:7179 "EHLO na01-bl2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753843AbaF0Wtl (ORCPT ); Fri, 27 Jun 2014 18:49:41 -0400 Received: from CH1PR03CA006.namprd03.prod.outlook.com (10.255.156.151) by BL2PR03MB497.namprd03.prod.outlook.com (10.141.93.142) with Microsoft SMTP Server (TLS) id 15.0.969.15; Fri, 27 Jun 2014 22:49:19 +0000 Received: from BN1AFFO11FD040.protection.gbl (10.255.156.132) by CH1PR03CA006.outlook.office365.com (10.255.156.151) with Microsoft SMTP Server (TLS) id 15.0.974.11 via Frontend Transport; Fri, 27 Jun 2014 22:49:18 +0000 Received: from tx30smr01.am.freescale.net (192.88.168.50) by BN1AFFO11FD040.mail.protection.outlook.com (10.58.52.251) with Microsoft SMTP Server (TLS) id 15.0.969.12 via Frontend Transport; Fri, 27 Jun 2014 22:49:18 +0000 Received: from fsr-fed1764-012.ea.freescale.net (fsr-fed1764-012-010171073213.ea.freescale.net [10.171.73.213]) by tx30smr01.am.freescale.net (8.14.3/8.14.0) with ESMTP id s5RMnAoW008904; Fri, 27 Jun 2014 15:49:16 -0700 From: Mihai Caraman To: CC: , , Mihai Caraman Subject: [PATCH 4/5 v4] KVM: PPC: Alow kvmppc_get_last_inst() to fail Date: Sat, 28 Jun 2014 01:49:06 +0300 Message-ID: <1403909347-31622-5-git-send-email-mihai.caraman@freescale.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1403909347-31622-1-git-send-email-mihai.caraman@freescale.com> References: <1403909347-31622-1-git-send-email-mihai.caraman@freescale.com> X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:192.88.168.50; CTRY:US; IPV:CAL; IPV:NLI; EFV:NLI; SFV:NSPM; SFS:(6009001)(189002)(199002)(88136002)(92566001)(4396001)(106466001)(50226001)(89996001)(93916002)(48376002)(77982001)(19580395003)(21056001)(47776003)(99396002)(85852003)(83072002)(102836001)(86362001)(92726001)(74502001)(64706001)(2351001)(87286001)(44976005)(46102001)(79102001)(229853001)(6806004)(107046002)(81342001)(19580405001)(74662001)(68736004)(81542001)(83322001)(85306003)(87936001)(104166001)(36756003)(95666004)(50986999)(26826002)(77156001)(33646001)(20776003)(105606002)(80022001)(31966008)(84676001)(104016002)(97736001)(76482001)(50466002)(62966002)(76176999)(21314002)(309714004); DIR:OUT; SFP:; SCL:1; SRVR:BL2PR03MB497; H:tx30smr01.am.freescale.net; FPR:; MLV:ovrnspm; PTR:InfoDomainNonexistent; MX:1; A:1; LANG:en; MIME-Version: 1.0 X-Microsoft-Antispam: BCL:0;PCL:0;RULEID: X-Forefront-PRVS: 0255DF69B9 Received-SPF: Fail (: domain of freescale.com does not designate 192.88.168.50 as permitted sender) receiver=; client-ip=192.88.168.50; helo=tx30smr01.am.freescale.net; Authentication-Results: spf=fail (sender IP is 192.88.168.50) smtp.mailfrom=mihai.caraman@freescale.com; X-OriginatorOrg: freescale.com Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org On book3e, guest last instruction is read on the exit path using load external pid (lwepx) dedicated instruction. This load operation may fail due to TLB eviction and execute-but-not-read entries. This patch lay down the path for an alternative solution to read the guest last instruction, by allowing kvmppc_get_lat_inst() function to fail. Architecture specific implmentations of kvmppc_load_last_inst() may read last guest instruction and instruct the emulation layer to re-execute the guest in case of failure. Make kvmppc_get_last_inst() definition common between architectures. Signed-off-by: Mihai Caraman --- v4: - these changes compile on book3s, please validate the functionality and do the necessary adaptations! - common declaration and enum for kvmppc_load_last_inst() - remove kvmppc_read_inst() in a preceding patch v3: - rework patch description - add common definition for kvmppc_get_last_inst() - check return values in book3s code v2: - integrated kvmppc_get_last_inst() in book3s code and checked build - addressed cosmetic feedback arch/powerpc/include/asm/kvm_book3s.h | 26 ------------------ arch/powerpc/include/asm/kvm_booke.h | 5 ---- arch/powerpc/include/asm/kvm_ppc.h | 24 +++++++++++++++++ arch/powerpc/kvm/book3s.c | 11 ++++++++ arch/powerpc/kvm/book3s_64_mmu_hv.c | 17 ++++-------- arch/powerpc/kvm/book3s_paired_singles.c | 38 +++++++++++++++++---------- arch/powerpc/kvm/book3s_pr.c | 45 ++++++++++++++++++++++++-------- arch/powerpc/kvm/booke.c | 3 +++ arch/powerpc/kvm/e500_mmu_host.c | 6 +++++ arch/powerpc/kvm/emulate.c | 18 ++++++++----- arch/powerpc/kvm/powerpc.c | 11 ++++++-- 11 files changed, 128 insertions(+), 76 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index ceb70aa..1300cd9 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -276,32 +276,6 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) return (kvmppc_get_msr(vcpu) & MSR_LE) != (MSR_KERNEL & MSR_LE); } -static inline u32 kvmppc_get_last_inst_internal(struct kvm_vcpu *vcpu, ulong pc) -{ - /* Load the instruction manually if it failed to do so in the - * exit path */ - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) - kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); - - return kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : - vcpu->arch.last_inst; -} - -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) -{ - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu)); -} - -/* - * Like kvmppc_get_last_inst(), but for fetching a sc instruction. - * Because the sc instruction sets SRR0 to point to the following - * instruction, we have to fetch from pc - 4. - */ -static inline u32 kvmppc_get_last_sc(struct kvm_vcpu *vcpu) -{ - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu) - 4); -} - static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) { return vcpu->arch.fault_dar; diff --git a/arch/powerpc/include/asm/kvm_booke.h b/arch/powerpc/include/asm/kvm_booke.h index c7aed61..cbb1990 100644 --- a/arch/powerpc/include/asm/kvm_booke.h +++ b/arch/powerpc/include/asm/kvm_booke.h @@ -69,11 +69,6 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) return false; } -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) -{ - return vcpu->arch.last_inst; -} - static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val) { vcpu->arch.ctr = val; diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index e2fd5a1..ec326c8 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -47,6 +47,11 @@ enum emulation_result { EMULATE_EXIT_USER, /* emulation requires exit to user-space */ }; +enum instruction_type { + INST_GENERIC, + INST_SC, /* system call */ +}; + extern int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); extern int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu); extern void kvmppc_handler_highmem(void); @@ -62,6 +67,9 @@ extern int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, u64 val, unsigned int bytes, int is_default_endian); +extern int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, + enum instruction_type type, u32 *inst); + extern int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu); extern int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu); @@ -234,6 +242,22 @@ struct kvmppc_ops { extern struct kvmppc_ops *kvmppc_hv_ops; extern struct kvmppc_ops *kvmppc_pr_ops; +static inline int kvmppc_get_last_inst(struct kvm_vcpu *vcpu, + enum instruction_type type, u32 *inst) +{ + int ret = EMULATE_DONE; + + /* Load the instruction manually if it failed to do so in the + * exit path */ + if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) + ret = kvmppc_load_last_inst(vcpu, type, &vcpu->arch.last_inst); + + *inst = kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : + vcpu->arch.last_inst; + + return ret; +} + static inline bool is_kvmppc_hv_enabled(struct kvm *kvm) { return kvm->arch.kvm_ops == kvmppc_hv_ops; diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index bd75902..c17f101 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -467,6 +467,17 @@ mmio: } EXPORT_SYMBOL_GPL(kvmppc_ld); +int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, enum instruction_type type, + u32 *inst) +{ + ulong pc = kvmppc_get_pc(vcpu); + + if (type == INST_SC) + pc -= 4; + return kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); +} +EXPORT_SYMBOL_GPL(kvmppc_load_last_inst); + int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) { return 0; diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 8056107..2c2b7ad 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -530,21 +530,14 @@ static int instruction_is_store(unsigned int instr) static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned long gpa, gva_t ea, int is_store) { - int ret; u32 last_inst; - unsigned long srr0 = kvmppc_get_pc(vcpu); - /* We try to load the last instruction. We don't let - * emulate_instruction do it as it doesn't check what - * kvmppc_ld returns. + /* * If we fail, we just return to the guest and try executing it again. */ - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) { - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); - if (ret != EMULATE_DONE || last_inst == KVM_INST_FETCH_FAILED) - return RESUME_GUEST; - vcpu->arch.last_inst = last_inst; - } + if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) != + EMULATE_DONE) + return RESUME_GUEST; /* * WARNING: We do not know for sure whether the instruction we just @@ -558,7 +551,7 @@ static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, * we just return and retry the instruction. */ - if (instruction_is_store(kvmppc_get_last_inst(vcpu)) != !!is_store) + if (instruction_is_store(last_inst) != !!is_store) return RESUME_GUEST; /* diff --git a/arch/powerpc/kvm/book3s_paired_singles.c b/arch/powerpc/kvm/book3s_paired_singles.c index 6c8011f..bfb8035 100644 --- a/arch/powerpc/kvm/book3s_paired_singles.c +++ b/arch/powerpc/kvm/book3s_paired_singles.c @@ -639,26 +639,36 @@ static int kvmppc_ps_one_in(struct kvm_vcpu *vcpu, bool rc, int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu) { - u32 inst = kvmppc_get_last_inst(vcpu); + u32 inst; enum emulation_result emulated = EMULATE_DONE; + int ax_rd, ax_ra, ax_rb, ax_rc; + short full_d; + u64 *fpr_d, *fpr_a, *fpr_b, *fpr_c; - int ax_rd = inst_get_field(inst, 6, 10); - int ax_ra = inst_get_field(inst, 11, 15); - int ax_rb = inst_get_field(inst, 16, 20); - int ax_rc = inst_get_field(inst, 21, 25); - short full_d = inst_get_field(inst, 16, 31); - - u64 *fpr_d = &VCPU_FPR(vcpu, ax_rd); - u64 *fpr_a = &VCPU_FPR(vcpu, ax_ra); - u64 *fpr_b = &VCPU_FPR(vcpu, ax_rb); - u64 *fpr_c = &VCPU_FPR(vcpu, ax_rc); - - bool rcomp = (inst & 1) ? true : false; - u32 cr = kvmppc_get_cr(vcpu); + bool rcomp; + u32 cr; #ifdef DEBUG int i; #endif + emulated = kvmppc_get_last_inst(vcpu, INST_GENERIC, &inst); + if (emulated != EMULATE_DONE) + return emulated; + + ax_rd = inst_get_field(inst, 6, 10); + ax_ra = inst_get_field(inst, 11, 15); + ax_rb = inst_get_field(inst, 16, 20); + ax_rc = inst_get_field(inst, 21, 25); + full_d = inst_get_field(inst, 16, 31); + + fpr_d = &VCPU_FPR(vcpu, ax_rd); + fpr_a = &VCPU_FPR(vcpu, ax_ra); + fpr_b = &VCPU_FPR(vcpu, ax_rb); + fpr_c = &VCPU_FPR(vcpu, ax_rc); + + rcomp = (inst & 1) ? true : false; + cr = kvmppc_get_cr(vcpu); + if (!kvmppc_inst_is_paired_single(vcpu, inst)) return EMULATE_FAIL; diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index d247d88..7bbaeec 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -970,15 +970,24 @@ int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, { enum emulation_result er; ulong flags; + u32 last_inst; + int emul; program_interrupt: flags = vcpu->arch.shadow_srr1 & 0x1f0000ull; + emul = kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst); + if (emul != EMULATE_DONE) { + r = RESUME_GUEST; + break; + } + if (kvmppc_get_msr(vcpu) & MSR_PR) { #ifdef EXIT_DEBUG - printk(KERN_INFO "Userspace triggered 0x700 exception at 0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); + pr_info("Userspace triggered 0x700 exception at\n 0x%lx (0x%x)\n", + kvmppc_get_pc(vcpu), last_inst); #endif - if ((kvmppc_get_last_inst(vcpu) & 0xff0007ff) != + if ((last_inst & 0xff0007ff) != (INS_DCBZ & 0xfffffff7)) { kvmppc_core_queue_program(vcpu, flags); r = RESUME_GUEST; @@ -997,7 +1006,7 @@ program_interrupt: break; case EMULATE_FAIL: printk(KERN_CRIT "%s: emulation at %lx failed (%08x)\n", - __func__, kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); + __func__, kvmppc_get_pc(vcpu), last_inst); kvmppc_core_queue_program(vcpu, flags); r = RESUME_GUEST; break; @@ -1014,8 +1023,25 @@ program_interrupt: break; } case BOOK3S_INTERRUPT_SYSCALL: + { + u32 last_sc; + int emul; + + /* Get last sc for papr */ + if (vcpu->arch.papr_enabled) { + /* + * The sc instuction sets SRR0 to point to the next inst + */ + emul = kvmppc_get_last_inst(vcpu, INST_SC, &last_sc); + if (emul != EMULATE_DONE) { + kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) - 4); + r = RESUME_GUEST; + break; + } + } + if (vcpu->arch.papr_enabled && - (kvmppc_get_last_sc(vcpu) == 0x44000022) && + (last_sc == 0x44000022) && !(kvmppc_get_msr(vcpu) & MSR_PR)) { /* SC 1 papr hypercalls */ ulong cmd = kvmppc_get_gpr(vcpu, 3); @@ -1060,13 +1086,13 @@ program_interrupt: r = RESUME_GUEST; } break; + } case BOOK3S_INTERRUPT_FP_UNAVAIL: case BOOK3S_INTERRUPT_ALTIVEC: case BOOK3S_INTERRUPT_VSX: { int ext_msr = 0; int emul; - ulong pc; u32 last_inst; if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) { @@ -1090,9 +1116,7 @@ program_interrupt: break; } - pc = kvmppc_get_pc(vcpu); - last_inst = kvmppc_get_last_inst(vcpu); - emul = kvmppc_ld(vcpu, &pc, sizeof(u32), &last_inst, false); + emul = kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst); if (emul == EMULATE_DONE) { /* we need to emulate this instruction */ goto program_interrupt; @@ -1105,9 +1129,8 @@ program_interrupt: } case BOOK3S_INTERRUPT_ALIGNMENT: { - ulong pc = kvmppc_get_pc(vcpu); - u32 last_inst = kvmppc_get_last_inst(vcpu); - int emul = kvmppc_ld(vcpu, &pc, sizeof(u32), &last_inst, false); + u32 last_inst; + int emul = kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst); if (emul == EMULATE_DONE) { u32 dsisr; diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index ab62109..34a42b9 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -752,6 +752,9 @@ static int emulation_exit(struct kvm_run *run, struct kvm_vcpu *vcpu) * they were actually modified by emulation. */ return RESUME_GUEST_NV; + case EMULATE_AGAIN: + return RESUME_GUEST; + case EMULATE_DO_DCR: run->exit_reason = KVM_EXIT_DCR; return RESUME_HOST; diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index dd2cc03..4b4e8d6 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -606,6 +606,12 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr, } } +int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, enum instruction_type type, + u32 *instr) +{ + return EMULATE_FAIL; +} + /************* MMU Notifiers *************/ int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index da86d9b..c5c64b6 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -224,19 +224,25 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) * from opcode tables in the future. */ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) { - u32 inst = kvmppc_get_last_inst(vcpu); - int ra = get_ra(inst); - int rs = get_rs(inst); - int rt = get_rt(inst); - int sprn = get_sprn(inst); - enum emulation_result emulated = EMULATE_DONE; + u32 inst; + int ra, rs, rt, sprn; + enum emulation_result emulated; int advance = 1; /* this default type might be overwritten by subcategories */ kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); + emulated = kvmppc_get_last_inst(vcpu, false, &inst); + if (emulated != EMULATE_DONE) + return emulated; + pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); + ra = get_ra(inst); + rs = get_rs(inst); + rt = get_rt(inst); + sprn = get_sprn(inst); + switch (get_op(inst)) { case OP_TRAP: #ifdef CONFIG_PPC_BOOK3S diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 7efc2b7..da54e4b 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -261,6 +261,9 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) * actually modified. */ r = RESUME_GUEST_NV; break; + case EMULATE_AGAIN: + r = RESUME_GUEST; + break; case EMULATE_DO_MMIO: run->exit_reason = KVM_EXIT_MMIO; /* We must reload nonvolatiles because "update" load/store @@ -270,11 +273,15 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) r = RESUME_HOST_NV; break; case EMULATE_FAIL: + { + u32 last_inst; + + kvmppc_get_last_inst(vcpu, false, &last_inst); /* XXX Deliver Program interrupt to guest. */ - printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__, - kvmppc_get_last_inst(vcpu)); + pr_emerg("%s: emulation failed (%08x)\n", __func__, last_inst); r = RESUME_HOST; break; + } default: WARN_ON(1); r = RESUME_GUEST;