From nobody Tue Oct 7 16:04:26 2025 Received: from mail-wm1-f74.google.com (mail-wm1-f74.google.com [209.85.128.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E1F8E27C175 for ; Wed, 9 Jul 2025 08:11:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752048694; cv=none; b=OzEXPIlGC75AkfOSWgrtduamnjF6uGPTad13NNIL3DZ6QEPFM5NByCG6tZHtHXxvFvV+Pngtv9uDPvzSlEoWEB7aC0ShlQ9dQBAPwvTpWKosKnnF3tOc+X9bQkHxP/KtRC1uFAGU+vRR7JUxfdo8epDPQxPVm6jrgw3E8pk/RtM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752048694; c=relaxed/simple; bh=jvdJzaCEv0k/GcxYI/bLqbb+kNCSjp0cy3X3jI0kiIU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=HdOqpm6GWJSjmHDsiZCciIvpoRLKSWgv4VTI0kZyU5T3N3Y4ShxVwA+wm0uMTjrwwn+KbsoOIa3Bhsl8xlT8ItUerha/KJ5FZoe6rTdOctTyVFyt9vggbMnfUOblV9Z5wTID0UZc34/63Y3QCP10atBmiS+t9wmCDzggwuv0w6I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Y1pDunto; arc=none smtp.client-ip=209.85.128.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Y1pDunto" Received: by mail-wm1-f74.google.com with SMTP id 5b1f17b1804b1-45311704d1fso34468565e9.1 for ; Wed, 09 Jul 2025 01:11:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1752048691; x=1752653491; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=C8zEEV0k0V04hhlMfC1WwEc4eqVxDysgmOU00FHLTTo=; b=Y1pDuntoOc34H91LbwnI3A32faFc4wdrP6cGoKzFPctOgJVvGtCw7aNvdQ0BLRL8Nt 2OPmFBTcbAcjnhmDCeyldEwrA6JE5NJjXyfceadZ4i1r3n+8FGFtro6/GiPXp3vQd1aw v7LGVBuF88ptT5rOr6jo/IkvMrVCkTNWMxqVxKfKYgJsxnfPlqpcVweq5p58v269IURz MDOTlKlH95GbYxigVNY7KOOU9DSBVrO9KWGw7b8JC9XyTFaxlbE5BUhcqI4LnBSqEb98 ouJY977ED/h2KKba4nZOeWWqnh2bwZxQcLcladBAAVl2qAHT7ec/ITdf8qziTF3AxEep DYIg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1752048691; x=1752653491; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=C8zEEV0k0V04hhlMfC1WwEc4eqVxDysgmOU00FHLTTo=; b=SbnwJ9x9PImJXJz10CHVV1AOIHyTGVif0s3wMrbcdH2Vw0eqYJT37ecrkvQGWabcPO 305LibqsMGYcc4KYvuuE9zQQsKgRv9zfzVr65WOkzzRGbGtDG/HgwJLYuJtSZ0h7K8Ru INPWMBjXpYtWa2flMccsNc05Uc2BBGd1pRvnoe9D37vHWnURweWdrgEHac6NFE1KGeFi 0jEffO2BBAX9red16HtkCS5ENdoFJZMly8LcfHnv2ndM5HyXE2cYix+/25YQljm+0num rFM6cPr/tD0rOvEx3sxUWnNVS0manmWRQ0ltnp5DV2ABjSfWVAVn4ebMP4oNHy8TJASS NrEg== X-Gm-Message-State: AOJu0YxtNfhRs7BxMG+sXBsMDxmnI9iQX6/2AtTYWojqG+7Of90W6NDQ yQ5H+y/iDAwNKrgIfROwWYqmzV039hQts5Y9mFcDfT6Qo4O577n0uZhBCF5MY51RyDfmiT2eh/2 WNAA4qhABsRfAm9vcrZF5A/Ex5eDOPSwhRYVwX/bPiDu2WIcwaehzf3lvIc/t67ObBN/PxLxzvg AYRc4Opg3Ilk9RBdDLrt+uUO7jl8QNvX+jXQ== X-Google-Smtp-Source: AGHT+IEdZORNPphu+mvo+KEMZneLj4yaAV2b0INhZrtb4dCFEIZhRclR5jpzQvG4KiAoT8kk4rgHJSlc X-Received: from wmbh3.prod.google.com ([2002:a05:600c:a103:b0:442:dc75:51ef]) (user=ardb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:6989:b0:43c:f629:66f4 with SMTP id 5b1f17b1804b1-454d523bbd6mr13706085e9.0.1752048691396; Wed, 09 Jul 2025 01:11:31 -0700 (PDT) Date: Wed, 9 Jul 2025 10:08:55 +0200 In-Reply-To: <20250709080840.2233208-26-ardb+git@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250709080840.2233208-26-ardb+git@google.com> X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-Developer-Signature: v=1; a=openpgp-sha256; l=5030; i=ardb@kernel.org; h=from:subject; bh=tvzBcQkTV7J9OoV2SLp4+keidchj+zYgpljjyN1cVzA=; b=owGbwMvMwCVmkMcZplerG8N4Wi2JISNP+VLWxAtFc/9nVagFNAsvvJFimJCVktfebPsxJKzgj LXjxd8dpSwMYlwMsmKKLAKz/77beXqiVK3zLFmYOaxMIEMYuDgFYCK3TzH8L96Z8XXuloVPmczV jH64OWgaKPTOPndifaqQ3MrMpv42EYb/CTZnFJiq4rQ4rgtIh221bqx4aCgwV3PzbPXlF17GlmY yAQA= X-Mailer: git-send-email 2.50.0.727.gbf7dc18ff4-goog Message-ID: <20250709080840.2233208-40-ardb+git@google.com> Subject: [PATCH v4 14/24] x86/sev: Provide PIC aliases for SEV related data objects From: Ard Biesheuvel To: linux-kernel@vger.kernel.org Cc: linux-efi@vger.kernel.org, x86@kernel.org, Ard Biesheuvel , Borislav Petkov , Ingo Molnar , Dionna Amalie Glaze , Kevin Loughlin , Tom Lendacky , Josh Poimboeuf , Peter Zijlstra Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Ard Biesheuvel Provide PIC aliases for data objects that are shared between the SEV startup code and the SEV code that executes later. This is needed so that the confined startup code is permitted to access them. This requires some of these variables to be moved into a source file that is not part of the startup code, as the PIC alias is already implied, and exporting variables in the opposite direction is not supported. Move ghcb_version as well, but don't provide a PIC alias as it is not actually needed. Signed-off-by: Ard Biesheuvel --- arch/x86/boot/compressed/sev.c | 3 ++ arch/x86/boot/startup/sev-shared.c | 19 ----------- arch/x86/boot/startup/sev-startup.c | 9 ------ arch/x86/coco/sev/core.c | 34 ++++++++++++++++++++ 4 files changed, 37 insertions(+), 28 deletions(-) diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c index 4bd7b45562ed..5e0fa165e10b 100644 --- a/arch/x86/boot/compressed/sev.c +++ b/arch/x86/boot/compressed/sev.c @@ -38,6 +38,9 @@ struct ghcb *boot_ghcb; #define __BOOT_COMPRESSED =20 u8 snp_vmpl; +u16 ghcb_version; + +u64 boot_svsm_caa_pa; =20 /* Include code for early handlers */ #include "../../boot/startup/sev-shared.c" diff --git a/arch/x86/boot/startup/sev-shared.c b/arch/x86/boot/startup/sev= -shared.c index a1d27a418421..042eef7b3a2a 100644 --- a/arch/x86/boot/startup/sev-shared.c +++ b/arch/x86/boot/startup/sev-shared.c @@ -18,25 +18,6 @@ #define WARN(condition, format...) (!!(condition)) #endif =20 -/* - * SVSM related information: - * During boot, the page tables are set up as identity mapped and later - * changed to use kernel virtual addresses. Maintain separate virtual and - * physical addresses for the CAA to allow SVSM functions to be used dur= ing - * early boot, both with identity mapped virtual addresses and proper ke= rnel - * virtual addresses. - */ -u64 boot_svsm_caa_pa __ro_after_init; - -/* - * Since feature negotiation related variables are set early in the boot - * process they must reside in the .data section so as not to be zeroed - * out when the .bss section is later cleared. - * - * GHCB protocol version negotiated with the hypervisor. - */ -u16 ghcb_version __ro_after_init; - /* Copy of the SNP firmware's CPUID page. */ static struct snp_cpuid_table cpuid_table_copy __ro_after_init; =20 diff --git a/arch/x86/boot/startup/sev-startup.c b/arch/x86/boot/startup/se= v-startup.c index cba4fb4cace0..0eb31bf81899 100644 --- a/arch/x86/boot/startup/sev-startup.c +++ b/arch/x86/boot/startup/sev-startup.c @@ -41,15 +41,6 @@ #include #include =20 -/* Bitmap of SEV features supported by the hypervisor */ -u64 sev_hv_features __ro_after_init; - -/* Secrets page physical address from the CC blob */ -u64 sev_secrets_pa __ro_after_init; - -/* For early boot SVSM communication */ -struct svsm_ca boot_svsm_ca_page __aligned(PAGE_SIZE); - /* * Nothing shall interrupt this code path while holding the per-CPU * GHCB. The backup GHCB is only for NMIs interrupting this path. diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c index f73dea313f55..71a76fde3102 100644 --- a/arch/x86/coco/sev/core.c +++ b/arch/x86/coco/sev/core.c @@ -46,6 +46,29 @@ #include #include =20 +/* Bitmap of SEV features supported by the hypervisor */ +u64 sev_hv_features __ro_after_init; +SYM_PIC_ALIAS(sev_hv_features); + +/* Secrets page physical address from the CC blob */ +u64 sev_secrets_pa __ro_after_init; +SYM_PIC_ALIAS(sev_secrets_pa); + +/* For early boot SVSM communication */ +struct svsm_ca boot_svsm_ca_page __aligned(PAGE_SIZE); +SYM_PIC_ALIAS(boot_svsm_ca_page); + +/* + * SVSM related information: + * During boot, the page tables are set up as identity mapped and later + * changed to use kernel virtual addresses. Maintain separate virtual and + * physical addresses for the CAA to allow SVSM functions to be used dur= ing + * early boot, both with identity mapped virtual addresses and proper ke= rnel + * virtual addresses. + */ +u64 boot_svsm_caa_pa __ro_after_init; +SYM_PIC_ALIAS(boot_svsm_caa_pa); + DEFINE_PER_CPU(struct svsm_ca *, svsm_caa); DEFINE_PER_CPU(u64, svsm_caa_pa); =20 @@ -119,6 +142,17 @@ DEFINE_PER_CPU(struct sev_es_save_area *, sev_vmsa); */ u8 snp_vmpl __ro_after_init; EXPORT_SYMBOL_GPL(snp_vmpl); +SYM_PIC_ALIAS(snp_vmpl); + +/* + * Since feature negotiation related variables are set early in the boot + * process they must reside in the .data section so as not to be zeroed + * out when the .bss section is later cleared. + * + * GHCB protocol version negotiated with the hypervisor. + */ +u16 ghcb_version __ro_after_init; +SYM_PIC_ALIAS(ghcb_version); =20 /* For early boot hypervisor communication in SEV-ES enabled guests */ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE); --=20 2.50.0.727.gbf7dc18ff4-goog