From bf4b96bb542ee3fe913d0b9eb4d9c1046c429ac6 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 5 Dec 2019 18:06:51 +0000 Subject: KVM: arm64: Sanely ratelimit sysreg messages Currently kvm_pr_unimpl() is ratelimited, so print_sys_reg_instr() won't spam the console. However, someof its callers try to print some contextual information with kvm_err(), which is not ratelimited. This means that in some cases the context may be printed without the sysreg encoding, which isn't all that useful. Let's ensure that both are consistently printed together and ratelimited, by refactoring print_sys_reg_instr() so that some callers can provide it with an arbitrary format string. Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20191205180652.18671-2-mark.rutland@arm.com --- arch/arm64/kvm/sys_regs.c | 12 ++++++------ arch/arm64/kvm/sys_regs.h | 17 +++++++++++++++-- 2 files changed, 21 insertions(+), 8 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 2071260a275b..e8bf08e09f78 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2094,9 +2094,9 @@ static void unhandled_cp_access(struct kvm_vcpu *vcpu, WARN_ON(1); } - kvm_err("Unsupported guest CP%d access at: %08lx [%08lx]\n", - cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); - print_sys_reg_instr(params); + print_sys_reg_msg(params, + "Unsupported guest CP%d access at: %08lx [%08lx]\n", + cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); kvm_inject_undefined(vcpu); } @@ -2245,9 +2245,9 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu, if (likely(r)) { perform_access(vcpu, params, r); } else { - kvm_err("Unsupported guest sys_reg access at: %lx [%08lx]\n", - *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); - print_sys_reg_instr(params); + print_sys_reg_msg(params, + "Unsupported guest sys_reg access at: %lx [%08lx]\n", + *vcpu_pc(vcpu), *vcpu_cpsr(vcpu)); kvm_inject_undefined(vcpu); } return 1; diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index 9bca0312d798..5a6fc30f5989 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -62,11 +62,24 @@ struct sys_reg_desc { #define REG_HIDDEN_USER (1 << 0) /* hidden from userspace ioctls */ #define REG_HIDDEN_GUEST (1 << 1) /* hidden from guest */ -static inline void print_sys_reg_instr(const struct sys_reg_params *p) +static __printf(2, 3) +inline void print_sys_reg_msg(const struct sys_reg_params *p, + char *fmt, ...) { + va_list va; + + va_start(va, fmt); /* Look, we even formatted it for you to paste into the table! */ - kvm_pr_unimpl(" { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n", + kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n", + &(struct va_format){ fmt, &va }, p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read"); + va_end(va); +} + +static inline void print_sys_reg_instr(const struct sys_reg_params *p) +{ + /* GCC warns on an empty format string */ + print_sys_reg_msg(p, "%s", ""); } static inline bool ignore_write(struct kvm_vcpu *vcpu, -- cgit v1.2.3 From 54ad68b7776043a77c9bf0a67d49cd9cb261a8e7 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 5 Dec 2019 18:06:52 +0000 Subject: KVM: arm64: Don't log IMP DEF sysreg traps We don't intend to support IMPLEMENATION DEFINED system registers, but have to trap them (and emulate them as UNDEFINED). These traps aren't interesting to the system administrator or to the KVM developers, so let's not bother logging when we do so. Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20191205180652.18671-3-mark.rutland@arm.com --- arch/arm64/kvm/sys_regs.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index e8bf08e09f78..bd2ac3796d8d 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2229,6 +2229,12 @@ int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run) NULL, 0); } +static bool is_imp_def_sys_reg(struct sys_reg_params *params) +{ + // See ARM DDI 0487E.a, section D12.3.2 + return params->Op0 == 3 && (params->CRn & 0b1011) == 0b1011; +} + static int emulate_sys_reg(struct kvm_vcpu *vcpu, struct sys_reg_params *params) { @@ -2244,6 +2250,8 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu, if (likely(r)) { perform_access(vcpu, params, r); + } else if (is_imp_def_sys_reg(params)) { + kvm_inject_undefined(vcpu); } else { print_sys_reg_msg(params, "Unsupported guest sys_reg access at: %lx [%08lx]\n", -- cgit v1.2.3 From 1ce74e96c2407df2b5867e5d45a70aacb8923c14 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 12 Dec 2019 09:40:49 +0000 Subject: KVM: arm64: Ensure 'params' is initialised when looking up sys register MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") introduced 'find_reg_by_id()', which looks up a system register only if the 'id' index parameter identifies a valid system register. As part of the patch, existing callers of 'find_reg()' were ported over to the new interface, but this breaks 'index_to_sys_reg_desc()' in the case that the initial lookup in the vCPU target table fails because we will then call into 'find_reg()' for the system register table with an uninitialised 'param' as the key to the lookup. GCC 10 is bright enough to spot this (amongst a tonne of false positives, but hey!): | arch/arm64/kvm/sys_regs.c: In function ‘index_to_sys_reg_desc.part.0.isra’: | arch/arm64/kvm/sys_regs.c:983:33: warning: ‘params.Op2’ may be used uninitialized in this function [-Wmaybe-uninitialized] | 983 | (u32)(x)->CRn, (u32)(x)->CRm, (u32)(x)->Op2); | [...] Revert the hunk of 4b927b94d5df which breaks 'index_to_sys_reg_desc()' so that the old behaviour of checking the index upfront is restored. Fixes: 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Cc: Link: https://lore.kernel.org/r/20191212094049.12437-1-will@kernel.org --- arch/arm64/kvm/sys_regs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index bd2ac3796d8d..d78b726d4722 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2364,8 +2364,11 @@ static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu, if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG) return NULL; + if (!index_to_params(id, ¶ms)) + return NULL; + table = get_target_table(vcpu->arch.target, true, &num); - r = find_reg_by_id(id, ¶ms, table, num); + r = find_reg(¶ms, table, num); if (!r) r = find_reg(¶ms, sys_reg_descs, ARRAY_SIZE(sys_reg_descs)); -- cgit v1.2.3 From d89c69f42bf0fe42d1f52ea9b3dca15b1ade7601 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Wed, 18 Dec 2019 11:43:06 +1100 Subject: KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor Commit 22945688acd4 ("KVM: PPC: Book3S HV: Support reset of secure guest") added a call to uv_svm_terminate, which is an ultravisor call, without any check that the guest is a secure guest or even that the system has an ultravisor. On a system without an ultravisor, the ultracall will degenerate to a hypercall, but since we are not in KVM guest context, the hypercall will get treated as a system call, which could have random effects depending on what happens to be in r0, and could also corrupt the current task's kernel stack. Hence this adds a test for the guest being a secure guest before doing uv_svm_terminate(). Fixes: 22945688acd4 ("KVM: PPC: Book3S HV: Support reset of secure guest") Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_hv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index dc53578193ee..6ff3f896d908 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -4983,7 +4983,8 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm) if (nesting_enabled(kvm)) kvmhv_release_all_nested(kvm); kvm->arch.process_table = 0; - uv_svm_terminate(kvm->arch.lpid); + if (kvm->arch.secure_guest) + uv_svm_terminate(kvm->arch.lpid); kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0); } -- cgit v1.2.3 From 396d2e878f92ec108e4293f1c77ea3bc90b414ff Mon Sep 17 00:00:00 2001 From: Jim Mattson Date: Fri, 13 Dec 2019 16:15:15 -0800 Subject: kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD The host reports support for the synthetic feature X86_FEATURE_SSBD when any of the three following hardware features are set: CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] CPUID.80000008H:EBX.AMD_SSBD[bit 24] CPUID.80000008H:EBX.VIRT_SSBD[bit 25] Either of the first two hardware features implies the existence of the IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does not. Therefore, CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] should only be set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host. Fixes: 0c54914d0c52a ("KVM: x86: use Intel speculation bugs and features as derived in generic x86 code") Signed-off-by: Jim Mattson Reviewed-by: Jacob Xu Reviewed-by: Peter Shier Cc: Paolo Bonzini Cc: stable@vger.kernel.org Reported-by: Eric Biggers Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c0aa07487eb8..dd18aa6fa317 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -402,7 +402,8 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry, int index) entry->edx |= F(SPEC_CTRL); if (boot_cpu_has(X86_FEATURE_STIBP)) entry->edx |= F(INTEL_STIBP); - if (boot_cpu_has(X86_FEATURE_SSBD)) + if (boot_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) || + boot_cpu_has(X86_FEATURE_AMD_SSBD)) entry->edx |= F(SPEC_CTRL_SSBD); /* * We emulate ARCH_CAPABILITIES in software even -- cgit v1.2.3 From 8715f05269bfbc6453e25e80825d781a82902f8e Mon Sep 17 00:00:00 2001 From: Jim Mattson Date: Fri, 13 Dec 2019 16:15:16 -0800 Subject: kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD The host reports support for the synthetic feature X86_FEATURE_SSBD when any of the three following hardware features are set: CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] CPUID.80000008H:EBX.AMD_SSBD[bit 24] CPUID.80000008H:EBX.VIRT_SSBD[bit 25] Either of the first two hardware features implies the existence of the IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does not. Therefore, CPUID.80000008H:EBX.AMD_SSBD[bit 24] should only be set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host. Fixes: 4c6903a0f9d76 ("KVM: x86: fix reporting of AMD speculation bug CPUID leaf") Signed-off-by: Jim Mattson Reviewed-by: Jacob Xu Reviewed-by: Peter Shier Cc: Paolo Bonzini Cc: stable@vger.kernel.org Reported-by: Eric Biggers Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index dd18aa6fa317..bf715e5fd35c 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -760,7 +760,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function, entry->ebx |= F(AMD_IBRS); if (boot_cpu_has(X86_FEATURE_STIBP)) entry->ebx |= F(AMD_STIBP); - if (boot_cpu_has(X86_FEATURE_SSBD)) + if (boot_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) || + boot_cpu_has(X86_FEATURE_AMD_SSBD)) entry->ebx |= F(AMD_SSBD); if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS)) entry->ebx |= F(AMD_SSB_NO); -- cgit v1.2.3