From nobody Mon Feb 9 10:27:59 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5E9DF1E86F; Thu, 4 Apr 2024 09:11:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712221880; cv=none; b=THLHOp4+T1wZOTofPiVOriv94bLbepPwD84Cc7tDtVp6UQREqH+1FZafI3gDuOKkNPJiqDX5PL43td4v8GxlR31I2cA4zhCMfPr1hj3XZqLrcHYTMQ5YR7yPsZdl7AX1PBMaNFIOuORFD/DwwidOSOGne/ZHwchw5RM0370DH+8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712221880; c=relaxed/simple; bh=rp4Sif1zZ6vH5WmQft9eZ+WjU0jvt6p6GDS0S4wx6gM=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=C4jmEWEXLvL4WFnhJMaOad1WFTpDM1XEpXwxtz9asDWFMU5jHANcYm8crBH0YEOJlT+e8TyMiGDCed9JDcV0Obk+LJEWn86AXcLdwewDKX/5XVpPu8Z9kZVWkNUYHk62B+b7Ihg2eHnlvmplkAmT1e5LQa8+D1yNLDJM5FpspjM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=yYCaMPyO; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=qlulG60G; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="yYCaMPyO"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qlulG60G" Date: Thu, 04 Apr 2024 09:11:14 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1712221875; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UTjOneyw9ICdNfMU/OuehX0z+uIkl5iql4xkhAQ2nZI=; b=yYCaMPyOmxr6nnl3ucGMMogNAskmSQpME5XRoYQ2N52MieKogt6GNyNAuEXN5hUBvSmLWY X7FR52kIUuS6rk4LSWyhtmOKF8lF5oPpDg7YTQx4aqcgffWQ90Vj8DaPZxbyIRveh9Uz4A 3l+OBVxh2OJXZbMnWxuSPuycHeFc1tzLzoqPS8tOwt8PkOoXQbLrrZWXvWBB5vBQ0Efzky DvZM3gaiR1cNyhzeW3CeOt3vK/ZnPTlMv/5Pf3o54wZdVHKvOw3xFWiooo0Cx9v8zK5ypc BT+WDSPtbMIohgus6jrQWRByVI+NNw8q6CW7PoPwT9jOyPohXaJVdT2yOnc/tQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1712221875; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UTjOneyw9ICdNfMU/OuehX0z+uIkl5iql4xkhAQ2nZI=; b=qlulG60GcGVyFnUaVIgqLNzae2ZwLQz2bPR51IWBsRytplEJ94QyCNIT431DYcOnVZCCPh C4u7CP3bFtFbmYCw== From: "tip-bot2 for Borislav Petkov (AMD)" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/urgent] x86/CPU/AMD: Track SNP host status with cc_platform_*() Cc: "Borislav Petkov (AMD)" , Tom Lendacky , Srikanth Aithal , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20240327154317.29909-6-bp@alien8.de> References: <20240327154317.29909-6-bp@alien8.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <171222187434.10875.5343618940901502172.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/urgent branch of tip: Commit-ID: 0ecaefb303de69929dc0036d5021d01cec7ea052 Gitweb: https://git.kernel.org/tip/0ecaefb303de69929dc0036d5021d01ce= c7ea052 Author: Borislav Petkov (AMD) AuthorDate: Wed, 27 Mar 2024 16:43:17 +01:00 Committer: Borislav Petkov (AMD) CommitterDate: Thu, 04 Apr 2024 10:40:30 +02:00 x86/CPU/AMD: Track SNP host status with cc_platform_*() The host SNP worthiness can determined later, after alternatives have been patched, in snp_rmptable_init() depending on cmdline options like iommu=3Dpt which is incompatible with SNP, for example. Which means that one cannot use X86_FEATURE_SEV_SNP and will need to have a special flag for that control. Use that newly added CC_ATTR_HOST_SEV_SNP in the appropriate places. Move kdump_sev_callback() to its rightful place, while at it. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Tom Lendacky Tested-by: Srikanth Aithal Link: https://lore.kernel.org/r/20240327154317.29909-6-bp@alien8.de --- arch/x86/include/asm/sev.h | 4 +-- arch/x86/kernel/cpu/amd.c | 38 +++++++++++++++++------------ arch/x86/kernel/cpu/mtrr/generic.c | 2 +- arch/x86/kernel/sev.c | 10 +-------- arch/x86/kvm/svm/sev.c | 2 +- arch/x86/virt/svm/sev.c | 26 +++++++++++++------- drivers/crypto/ccp/sev-dev.c | 2 +- drivers/iommu/amd/init.c | 4 ++- 8 files changed, 49 insertions(+), 39 deletions(-) diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index 07e125f..7f57382 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -228,7 +228,6 @@ int snp_issue_guest_request(u64 exit_code, struct snp_r= eq_data *input, struct sn void snp_accept_memory(phys_addr_t start, phys_addr_t end); u64 snp_get_unsupported_features(u64 status); u64 sev_get_status(void); -void kdump_sev_callback(void); void sev_show_status(void); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } @@ -258,7 +257,6 @@ static inline int snp_issue_guest_request(u64 exit_code= , struct snp_req_data *in static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) {= } static inline u64 snp_get_unsupported_features(u64 status) { return 0; } static inline u64 sev_get_status(void) { return 0; } -static inline void kdump_sev_callback(void) { } static inline void sev_show_status(void) { } #endif =20 @@ -270,6 +268,7 @@ int psmash(u64 pfn); int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid, bool= immutable); int rmp_make_shared(u64 pfn, enum pg_level level); void snp_leak_pages(u64 pfn, unsigned int npages); +void kdump_sev_callback(void); #else static inline bool snp_probe_rmptable_info(void) { return false; } static inline int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level)= { return -ENODEV; } @@ -282,6 +281,7 @@ static inline int rmp_make_private(u64 pfn, u64 gpa, en= um pg_level level, u32 as } static inline int rmp_make_shared(u64 pfn, enum pg_level level) { return -= ENODEV; } static inline void snp_leak_pages(u64 pfn, unsigned int npages) {} +static inline void kdump_sev_callback(void) { } #endif =20 #endif diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 6d8677e..9bf17c9 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -345,6 +345,28 @@ static void srat_detect_node(struct cpuinfo_x86 *c) #endif } =20 +static void bsp_determine_snp(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_ARCH_HAS_CC_PLATFORM + cc_vendor =3D CC_VENDOR_AMD; + + if (cpu_has(c, X86_FEATURE_SEV_SNP)) { + /* + * RMP table entry format is not architectural and is defined by the + * per-processor PPR. Restrict SNP support on the known CPU models + * for which the RMP table entry format is currently defined for. + */ + if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && + c->x86 >=3D 0x19 && snp_probe_rmptable_info()) { + cc_platform_set(CC_ATTR_HOST_SEV_SNP); + } else { + setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); + cc_platform_clear(CC_ATTR_HOST_SEV_SNP); + } + } +#endif +} + static void bsp_init_amd(struct cpuinfo_x86 *c) { if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) { @@ -452,21 +474,7 @@ static void bsp_init_amd(struct cpuinfo_x86 *c) break; } =20 - if (cpu_has(c, X86_FEATURE_SEV_SNP)) { - /* - * RMP table entry format is not architectural and it can vary by proces= sor - * and is defined by the per-processor PPR. Restrict SNP support on the - * known CPU model and family for which the RMP table entry format is - * currently defined for. - */ - if (!boot_cpu_has(X86_FEATURE_ZEN3) && - !boot_cpu_has(X86_FEATURE_ZEN4) && - !boot_cpu_has(X86_FEATURE_ZEN5)) - setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); - else if (!snp_probe_rmptable_info()) - setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); - } - + bsp_determine_snp(c); return; =20 warn: diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/= generic.c index 422a4dd..7b29ebd 100644 --- a/arch/x86/kernel/cpu/mtrr/generic.c +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -108,7 +108,7 @@ static inline void k8_check_syscfg_dram_mod_en(void) (boot_cpu_data.x86 >=3D 0x0f))) return; =20 - if (cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return; =20 rdmsr(MSR_AMD64_SYSCFG, lo, hi); diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 7e1e63c..38ad066 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -2284,16 +2284,6 @@ static int __init snp_init_platform_device(void) } device_initcall(snp_init_platform_device); =20 -void kdump_sev_callback(void) -{ - /* - * Do wbinvd() on remote CPUs when SNP is enabled in order to - * safely do SNP_SHUTDOWN on the local CPU. - */ - if (cpu_feature_enabled(X86_FEATURE_SEV_SNP)) - wbinvd(); -} - void sev_show_status(void) { int i; diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index ae0ac12..3d310b4 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3174,7 +3174,7 @@ struct page *snp_safe_alloc_page(struct kvm_vcpu *vcp= u) unsigned long pfn; struct page *p; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); =20 /* diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index cffe115..ab0e844 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -77,7 +77,7 @@ static int __mfd_enable(unsigned int cpu) { u64 val; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return 0; =20 rdmsrl(MSR_AMD64_SYSCFG, val); @@ -98,7 +98,7 @@ static int __snp_enable(unsigned int cpu) { u64 val; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return 0; =20 rdmsrl(MSR_AMD64_SYSCFG, val); @@ -174,11 +174,11 @@ static int __init snp_rmptable_init(void) u64 rmptable_size; u64 val; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return 0; =20 if (!amd_iommu_snp_en) - return 0; + goto nosnp; =20 if (!probed_rmp_size) goto nosnp; @@ -225,7 +225,7 @@ skip_enable: return 0; =20 nosnp: - setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); + cc_platform_clear(CC_ATTR_HOST_SEV_SNP); return -ENOSYS; } =20 @@ -246,7 +246,7 @@ static struct rmpentry *__snp_lookup_rmpentry(u64 pfn, = int *level) { struct rmpentry *large_entry, *entry; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return ERR_PTR(-ENODEV); =20 entry =3D get_rmpentry(pfn); @@ -363,7 +363,7 @@ int psmash(u64 pfn) unsigned long paddr =3D pfn << PAGE_SHIFT; int ret; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return -ENODEV; =20 if (!pfn_valid(pfn)) @@ -472,7 +472,7 @@ static int rmpupdate(u64 pfn, struct rmp_state *state) unsigned long paddr =3D pfn << PAGE_SHIFT; int ret, level; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return -ENODEV; =20 level =3D RMP_TO_PG_LEVEL(state->pagesize); @@ -558,3 +558,13 @@ void snp_leak_pages(u64 pfn, unsigned int npages) spin_unlock(&snp_leaked_pages_list_lock); } EXPORT_SYMBOL_GPL(snp_leak_pages); + +void kdump_sev_callback(void) +{ + /* + * Do wbinvd() on remote CPUs when SNP is enabled in order to + * safely do SNP_SHUTDOWN on the local CPU. + */ + if (cc_platform_has(CC_ATTR_HOST_SEV_SNP)) + wbinvd(); +} diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index f44efbb..2102377 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -1090,7 +1090,7 @@ static int __sev_snp_init_locked(int *error) void *arg =3D &data; int cmd, rc =3D 0; =20 - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return -ENODEV; =20 sev =3D psp->sev_data; diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index e7a4492..33228c1 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -3228,7 +3228,7 @@ out: static void iommu_snp_enable(void) { #ifdef CONFIG_KVM_AMD_SEV - if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return; /* * The SNP support requires that IOMMU must be enabled, and is @@ -3236,12 +3236,14 @@ static void iommu_snp_enable(void) */ if (no_iommu || iommu_default_passthrough()) { pr_err("SNP: IOMMU disabled or configured in passthrough mode, SNP canno= t be supported.\n"); + cc_platform_clear(CC_ATTR_HOST_SEV_SNP); return; } =20 amd_iommu_snp_en =3D check_feature(FEATURE_SNP); if (!amd_iommu_snp_en) { pr_err("SNP: IOMMU SNP feature not enabled, SNP cannot be supported.\n"); + cc_platform_clear(CC_ATTR_HOST_SEV_SNP); return; }