From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1A90F338925; Mon, 9 Mar 2026 18:01:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079275; cv=none; b=NXFnl/LGAWSwirk749lwf61TSdhHjrBaVcfINNpgkMPuoIPznUuWXbAwNwAKj0nQrwjmquFAN94cBwJhT7gwdCh2yknxU4umwECkG3vUT9ZwEf0cvRgb4P9h1pvCYQyEbwb/Dpyaoq88HFeXsQbCEKbFc1AQvD58h7a3m7LhkKg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079275; c=relaxed/simple; bh=z1V7/CvNV0fc/gSHI53kaTC1XLix5Wdwxcqe0vVmlFg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LvAOwDi/KFG4ejs5+mRNTQiaQ6PBBtGtQihY9PrI/LkHBFETLJ4pIbqlVZ1kDJQADy/ihftSyFpq+DTI9lgP0Jeo5clxfzqjkHY0lIGuWPtP/9Ixbe3YBIawhBCJmyCtS3mm+BiPCs4OGZN5maA8UbWCmiyTWdKgZ8dV/MPAtcM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sdRaeRJV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sdRaeRJV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0CA7C2BC9E; Mon, 9 Mar 2026 18:01:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079275; bh=z1V7/CvNV0fc/gSHI53kaTC1XLix5Wdwxcqe0vVmlFg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sdRaeRJVOTmne3W8LRYSJjc891zlKZ61moM4mB2jLFwvKCbigR6TKqoA0y4U/vioo 0hOAUdDiGN07dW9KmmBNYAtR0cj7w/dl5SHmBQjTwlOkoIwY1T0FwLH3XdjkoyDJ7B XXJNqnohKbydLF8pYVEElQVEWkH5mRtpeAQMCCbKqalgmytgMwbrAwYQdxOlxwLUfy jEh5JG6z0GP86jkHoXthYicajXDwnt0cQdB17PrWOhmBp1ynMqx3QjyEZemPT7KVxS ku0RPLoD+/gIPp3Yo1xYg3wCMf0piXMRMtffEO9tRF0dRl3yW39/IlzTItGQm6rfAa x3OT0kyYmeGfg== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 01/10] x86/snp: drop support for SNP hotplug Date: Mon, 9 Mar 2026 12:00:43 -0600 Message-ID: <20260309180053.2389118-2-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" During an SNP_INIT(_EX), the SEV firmware checks that all CPUs have the SNP syscfg bit set, and fails if they do not. As such, it does not make sense to have offline CPUs: the firmware will fail initialization because of the offlined ones that the kernel did not initialize. Futher, there is a bug: during SNP_INIT(_EX) the firmware requires the MFDM syscfg bit to be set in addition to having SNP enabled, which the previous hotplug code did not do. Since k8_check_syscfg_dram_mod_en() enforces this be cleared, hotplug wouldn't work. Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/virt/svm/sev.c | 32 +++++--------------------------- 1 file changed, 5 insertions(+), 27 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index a4f3a364fb65..f404c609582c 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -130,33 +130,20 @@ static unsigned long snp_nr_leaked_pages; #undef pr_fmt #define pr_fmt(fmt) "SEV-SNP: " fmt =20 -static int __mfd_enable(unsigned int cpu) +static __init void mfd_enable(void *arg) { - u64 val; - if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) - return 0; - - rdmsrq(MSR_AMD64_SYSCFG, val); - - val |=3D MSR_AMD64_SYSCFG_MFDM; - - wrmsrq(MSR_AMD64_SYSCFG, val); + return; =20 - return 0; + msr_set_bit(MSR_AMD64_SYSCFG, MSR_AMD64_SYSCFG_MFDM_BIT); } =20 -static __init void mfd_enable(void *arg) -{ - __mfd_enable(smp_processor_id()); -} - -static int __snp_enable(unsigned int cpu) +static __init void snp_enable(void *arg) { u64 val; =20 if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) - return 0; + return; =20 rdmsrq(MSR_AMD64_SYSCFG, val); =20 @@ -164,13 +151,6 @@ static int __snp_enable(unsigned int cpu) val |=3D MSR_AMD64_SYSCFG_SNP_VMPL_EN; =20 wrmsrq(MSR_AMD64_SYSCFG, val); - - return 0; -} - -static __init void snp_enable(void *arg) -{ - __snp_enable(smp_processor_id()); } =20 static void __init __snp_fixup_e820_tables(u64 pa) @@ -553,8 +533,6 @@ int __init snp_rmptable_init(void) on_each_cpu(snp_enable, NULL, 1); =20 skip_enable: - cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/rmptable_init:online", __snp_= enable, NULL); - /* * Setting crash_kexec_post_notifiers to 'true' to ensure that SNP panic * notifier is invoked to do SNP IOMMU shutdown before kdump. --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BB47E338925; Mon, 9 Mar 2026 18:01:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079277; cv=none; b=VaIPt9YdeG+8iXt3WFCIhedYbiYyoXUYtll20+vZ0p4BxiEq7vJwQkzzTxlm3mAh9GyP9E6YKJfoio4AnF8Enwc83CPs3/KfITgs9ICoOjfxRAlCOufKEmoskux+vzCURyiSAU4jnjOsM8uYyOQxY1K2l88GLGyMGtHPrkAFomw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079277; c=relaxed/simple; bh=u+Ieq1hHAY0K9hAW/Ho9/Yc9TVLd1TvPaORi0TZc1rc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gETv8drpyaoJ0TaoZ/CMfMzLADaa7KmEtwNhtCACLRy8FPvQ7dxbpCCi3Bz4fW3CuFZMItvY+0gJkENtGj1+gEG8/eucnQ/uylxPPPLQN9ZW5V6GGe5Y3zVdKqeWZ1PwmyhIsxsdejF7DuDdDCi7BmPLno4B4RHPuRxQuGZj3zo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jzsgwZBd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jzsgwZBd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4105AC4CEF7; Mon, 9 Mar 2026 18:01:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079277; bh=u+Ieq1hHAY0K9hAW/Ho9/Yc9TVLd1TvPaORi0TZc1rc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jzsgwZBd7KHMXkDD4Bs2O+vIQrPQgw8rksERaPa0CI3EBYK0Y6r55Pj4Dv0/GCEBg gOwkps6MlTRqCzoDxCNBJkCDAlzOWu03hxi59E8BGG8Rwye2xlAPe/RXwRIlAXS3q9 jl7sJj4CSPu83OSM3I/+y+Qh33K87nGXw0jyamDXRiOtRF7o86LqpVHeDsk79Plflw w2NEQTK3k5gaqDWu8O8USf4l3DjIZE7J0D19M5uG/GQwS03kdQ6AOTVo+2rA31m7U2 +0UEdaa2DZTOuq2sIbyhWrs+lnIe5UAKuyq6aUk1Ix1rY1+PjMthIdm23D51iKmjW8 PnTxiHEGoiWbg== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 02/10] x86/snp: drop WBINVD before setting SNPEn Date: Mon, 9 Mar 2026 12:00:44 -0600 Message-ID: <20260309180053.2389118-3-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" WBINVD is required before SNP_INIT(_EX), but not before setting SNPEn, since the ccp driver already does its own WBINVD before SNP_INIT (and this one would be too early for that anyway...). Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/virt/svm/sev.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index f404c609582c..5e07f103c271 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -524,9 +524,6 @@ int __init snp_rmptable_init(void) memset(desc->rmp_entry, 0, desc->size); } =20 - /* Flush the caches to ensure that data is written before SNP is enabled.= */ - wbinvd_on_all_cpus(); - /* MtrrFixDramModEn must be enabled on all the CPUs prior to enabling SNP= . */ on_each_cpu(mfd_enable, NULL, 1); =20 --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1A0E3341AB8; Mon, 9 Mar 2026 18:01:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079280; cv=none; b=NQ3xLlXLkymR4SBRzuzeQZYCboW5cviwJ0khR4wcbLNiOTGvVnnmvcvV8C3rGKE6bg/ht/fTpI1lW5zkbLn3ysnYhedhRVnJzVSGnwOOGp0qTKtsmkuwotAYVNU3v3QFJjzb+xPKIRUpjuxr445MpLTj2quIA0lzEOqf7FREmzk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079280; c=relaxed/simple; bh=BDixtaFz3x7404kL2sHxYmQyMahAC6eoXnMaU9q0KE8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pheVjyxACDVXYcpFd0P1XcFHydd+L2HQMs2ht2LVT1YJtsmD+7zo6B9Jf4r93aJsuBUPINhsEJJfHxjECfp5mE9qDMljjXhe9tk3tBAUJGHAGJNScJYc2MvhCm/DfWneU2cTvBhPm4d9WU+WthhFznSZQngJqSQHQIPuqf+ZIjc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bSfmPjMA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bSfmPjMA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A53E2C2BC87; Mon, 9 Mar 2026 18:01:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079279; bh=BDixtaFz3x7404kL2sHxYmQyMahAC6eoXnMaU9q0KE8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bSfmPjMAOAgU7mLnPh7qg1myIXkRtGXq0iladPN/65CwPy+l6uP+dommM7mKkWLeq wrjam9t5eQE4tCwE/FetP0LxjfLRKodixJYRdZvrkC5F+/55pZ8Xmo9rhEfBvolzE6 cljtmFKxKpbGG/rPbLQXzh52KkKaH5v92p54hCsddtWPnUkmgBjUN7I9vjpW+J0bx5 z4ntnwzAiqsqofqnWZ+uzdDL6HnfXDn/naEhssHIMluXZwtAOs7o63ICXV/zOtc0xP kJV1r/8Q3WLc1esBWdPUzxbwmJ1JGLFMHA8PKk/iuwUkmVOEENPxrco7MTKqy2xx5n tqEE6ARWAYcBw== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 03/10] x86/snp: Keep the RMP table bookkeeping area mapped Date: Mon, 9 Mar 2026 12:00:45 -0600 Message-ID: <20260309180053.2389118-4-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Tom Lendacky In preparation for delayed SNP initialization and disablement on shutdown, the RMP will need to be cleared each time SNP is disabled. Maintain the mapping to the RMP bookkeeping area to avoid mapping and unmapping it each time and any possible errors that may arise from that. Signed-off-by: Tom Lendacky Signed-off-by: Tycho Andersen (AMD) --- arch/x86/virt/svm/sev.c | 40 +++++++++++++++++----------------------- 1 file changed, 17 insertions(+), 23 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index 5e07f103c271..e35fac0a8a3d 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -117,6 +117,8 @@ static u64 rmp_segment_mask; =20 static u64 rmp_cfg; =20 +static void *rmp_bookkeeping __ro_after_init; + /* Mask to apply to a PFN to get the first PFN of a 2MB page */ #define PFN_PMD_MASK GENMASK_ULL(63, PMD_SHIFT - PAGE_SHIFT) =20 @@ -240,23 +242,6 @@ void __init snp_fixup_e820_tables(void) } } =20 -static bool __init clear_rmptable_bookkeeping(void) -{ - void *bk; - - bk =3D memremap(probed_rmp_base, RMPTABLE_CPU_BOOKKEEPING_SZ, MEMREMAP_WB= ); - if (!bk) { - pr_err("Failed to map RMP bookkeeping area\n"); - return false; - } - - memset(bk, 0, RMPTABLE_CPU_BOOKKEEPING_SZ); - - memunmap(bk); - - return true; -} - static bool __init alloc_rmp_segment_desc(u64 segment_pa, u64 segment_size= , u64 pa) { u64 rst_index, rmp_segment_size_max; @@ -474,10 +459,22 @@ static bool __init setup_segmented_rmptable(void) static bool __init setup_rmptable(void) { if (rmp_cfg & MSR_AMD64_SEG_RMP_ENABLED) { - return setup_segmented_rmptable(); + if (!setup_segmented_rmptable()) + return false; } else { - return setup_contiguous_rmptable(); + if (!setup_contiguous_rmptable()) + return false; } + + rmp_bookkeeping =3D memremap(probed_rmp_base, RMPTABLE_CPU_BOOKKEEPING_SZ= , MEMREMAP_WB); + if (!rmp_bookkeeping) { + pr_err("Failed to map RMP bookkeeping area\n"); + free_rmp_segment_table(); + + return false; + } + + return true; } =20 /* @@ -508,10 +505,7 @@ int __init snp_rmptable_init(void) goto skip_enable; =20 /* Zero out the RMP bookkeeping area */ - if (!clear_rmptable_bookkeeping()) { - free_rmp_segment_table(); - return -ENOSYS; - } + memset(rmp_bookkeeping, 0, RMPTABLE_CPU_BOOKKEEPING_SZ); =20 /* Zero out the RMP entries */ for (i =3D 0; i < rst_max_index; i++) { --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A30E73451B5; Mon, 9 Mar 2026 18:01:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079282; cv=none; b=Lej2BkIYrYXeOtcHyRxnTkXOLKeKq19Yk0or0rHdKLiHF0Rl2YMPmk0v+qglmxViPk6Vz6E4JZ5veMLSouzrIt95I9KoEI0GJeUAT7IdioFXSnXSx7+lagtV6MkrNaj/dnnbh631+F/sn4bSWrqRN7T98a3IkO+52Of2pty4hM8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079282; c=relaxed/simple; bh=GQScDmLliiJ2MTvHc5TZbOCnDLWhRNkUBAsHFpsWlP0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OpvjeQNxbQGMgzh+xm8DTzJO/PWqpcGT9NLUdF2rU1eIct5yukbPSyeZVnc6o6i9an9WW+XLswbGMSKCFlc4/wKBhFe+AQYRqiTcu1/9Z7GTqvcgjMWFamTcccd0asKUz1u4xwgFYfFeBNwysHMq7/2jOXZyaNkMX49BxRDxTNs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=d6moQUcD; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="d6moQUcD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 14F71C2BC9E; Mon, 9 Mar 2026 18:01:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079282; bh=GQScDmLliiJ2MTvHc5TZbOCnDLWhRNkUBAsHFpsWlP0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d6moQUcDLHXgrnKjnVIIltQebAaK2kQFve/zcLYlzHyz/gHFBaAFEjoy5zh2KoFJ9 dZA5/DrGYcoKtu7uWLKdn7LC9kD35LK7C1bGiDv3mSipx6PHl2xhTqofZ7T6cUHfCi FAQX8zAI4ahBZUjCm/YdObJF76AokYf9zrYrEN5ml3hu8/wUd7LqjyGZ+Z8vMQQFVc EV0y+RuB+/JadZu2gL6SYl1NrTsR5ngvgK0jYtx5Y4PuwNW67jcXsIbYLoxQzgohls DrWtCg6Mgr0TbyULHUQrgBrLINb3b0g3/W5a0WFDOJaDBl1vcJN1thqwiiv5wwxSH1 YsEgsxfwYX28A== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 04/10] x86/snp: Create a function to clear/zero the RMP Date: Mon, 9 Mar 2026 12:00:46 -0600 Message-ID: <20260309180053.2389118-5-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Tom Lendacky In prep for delayed SNP initialization and disablement on shutdown, create a function, snp_clear_rmp(), that clears the RMP bookkeeping area and the RMP entries. Signed-off-by: Tom Lendacky Signed-off-by: Tycho Andersen (AMD) --- arch/x86/virt/svm/sev.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index e35fac0a8a3d..f41b92e40014 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -242,6 +242,32 @@ void __init snp_fixup_e820_tables(void) } } =20 +static void snp_clear_rmp(void) +{ + unsigned int i; + u64 val; + + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) + return; + + /* Clearing the RMP while SNP is enabled will cause an exception */ + rdmsrq(MSR_AMD64_SYSCFG, val); + if (WARN_ON_ONCE(val & MSR_AMD64_SYSCFG_SNP_EN)) + return; + + memset(rmp_bookkeeping, 0, RMPTABLE_CPU_BOOKKEEPING_SZ); + + for (i =3D 0; i < rst_max_index; i++) { + struct rmp_segment_desc *desc; + + desc =3D rmp_segment_table[i]; + if (!desc) + continue; + + memset(desc->rmp_entry, 0, desc->size); + } +} + static bool __init alloc_rmp_segment_desc(u64 segment_pa, u64 segment_size= , u64 pa) { u64 rst_index, rmp_segment_size_max; @@ -484,7 +510,6 @@ static bool __init setup_rmptable(void) */ int __init snp_rmptable_init(void) { - unsigned int i; u64 val; =20 if (WARN_ON_ONCE(!cc_platform_has(CC_ATTR_HOST_SEV_SNP))) @@ -504,19 +529,7 @@ int __init snp_rmptable_init(void) if (val & MSR_AMD64_SYSCFG_SNP_EN) goto skip_enable; =20 - /* Zero out the RMP bookkeeping area */ - memset(rmp_bookkeeping, 0, RMPTABLE_CPU_BOOKKEEPING_SZ); - - /* Zero out the RMP entries */ - for (i =3D 0; i < rst_max_index; i++) { - struct rmp_segment_desc *desc; - - desc =3D rmp_segment_table[i]; - if (!desc) - continue; - - memset(desc->rmp_entry, 0, desc->size); - } + snp_clear_rmp(); =20 /* MtrrFixDramModEn must be enabled on all the CPUs prior to enabling SNP= . */ on_each_cpu(mfd_enable, NULL, 1); --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B5CEF346A0A; Mon, 9 Mar 2026 18:01:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079284; cv=none; b=hYAkv4B11nBy+evhaZnjDm0fc0ekZ7Hgb+U6EGCmttlevW9928kBKCBxxNhVucp2wXxqf6f04s/3blm60gzZQtWTr0S6ogGrwfjowAyNHeydHiR/JyNnMB2D0wNCDlpwTjdxR6RzIOgwdHg9DigjMSzFHXnsQRiPw3+FSMC8F1E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079284; c=relaxed/simple; bh=Rvrqna2pz4VDTbbcYe4HMaKIA2pZhmtaOF9TVxrmDiQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EyaQPsWwKhCpr5TTCnlHDbxyzeya3zaIJF9XawXQ2rId4R0qPDjViTQ1pmJ2OHfnP4kMHpy/eVbbEXB2w9Nz6OzqOl9t+U72jBdGElcIf92i2kJ3WF7zWz3Vd2IWyHQYTYwD7sj7YAxfrEHRY45VEiYT7nUOy3H9F3uOuHH8X2g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=poxpNNRA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="poxpNNRA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A4A7C4CEF7; Mon, 9 Mar 2026 18:01:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079284; bh=Rvrqna2pz4VDTbbcYe4HMaKIA2pZhmtaOF9TVxrmDiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=poxpNNRArFVUS6ll26B8V1mnFlqum9mGnZUOckJxZ1Rp/xY3tdq9l08OW0o1NGQ9z 0nlu45Ap0FP72rpNhTrGtZFEFx82s6ULdCl3cadR5LmUnCtb6GTF22IQndNbaButuz FglfsbrxfTcHVRUvF1hnChjwQXO4PQEKiKuztdtkk5txAiAIjNsiQ7/gGp4tpoQhqs Weh1Vi7RnjcYxkxelgTB46emwaFeew4FrzkK4/LkqrDPWsMtluVp2Wn+KZS5+Uoj2l ysyez4neVKL2gbpnop/Y/wXBmNhj6RxGGNo1m0CMT6+P6kZf5X0LInAcTLcfW7zVQY FTpBQb6CfnjLA== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 05/10] x86/snp: create snp_prepare_for_snp_init() Date: Mon, 9 Mar 2026 12:00:47 -0600 Message-ID: <20260309180053.2389118-6-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" In preparation for delayed SNP initialization, create a function snp_prepare_for_snp_init() that does the necessary architecture setup. Export this function for the ccp module to allow it to do the setup as necessary. Also move {mfd,snp}_enable out of the __init section, since these will be called later. Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/include/asm/sev.h | 2 ++ arch/x86/virt/svm/sev.c | 46 ++++++++++++++++++++++---------------- 2 files changed, 29 insertions(+), 19 deletions(-) diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index 0e6c0940100f..0bcd89d4fe90 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -661,6 +661,7 @@ static inline void snp_leak_pages(u64 pfn, unsigned int= pages) { __snp_leak_pages(pfn, pages, true); } +void snp_prepare_for_snp_init(void); #else static inline bool snp_probe_rmptable_info(void) { return false; } static inline int snp_rmptable_init(void) { return -ENOSYS; } @@ -677,6 +678,7 @@ static inline void __snp_leak_pages(u64 pfn, unsigned i= nt npages, bool dump_rmp) static inline void snp_leak_pages(u64 pfn, unsigned int npages) {} static inline void kdump_sev_callback(void) { } static inline void snp_fixup_e820_tables(void) {} +static inline void snp_prepare_for_snp_init(void) {} #endif =20 #endif diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index f41b92e40014..9d2cddbeaf21 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -132,7 +132,7 @@ static unsigned long snp_nr_leaked_pages; #undef pr_fmt #define pr_fmt(fmt) "SEV-SNP: " fmt =20 -static __init void mfd_enable(void *arg) +static void mfd_enable(void *arg) { if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return; @@ -140,7 +140,7 @@ static __init void mfd_enable(void *arg) msr_set_bit(MSR_AMD64_SYSCFG, MSR_AMD64_SYSCFG_MFDM_BIT); } =20 -static __init void snp_enable(void *arg) +static void snp_enable(void *arg) { u64 val; =20 @@ -503,6 +503,30 @@ static bool __init setup_rmptable(void) return true; } =20 +void snp_prepare_for_snp_init(void) +{ + u64 val; + + /* + * Check if SEV-SNP is already enabled, this can happen in case of + * kexec boot. + */ + rdmsrq(MSR_AMD64_SYSCFG, val); + if (val & MSR_AMD64_SYSCFG_SNP_EN) + return; + + snp_clear_rmp(); + + /* + * MtrrFixDramModEn is not shared between threads on a core, + * therefore it must be set on all CPUs prior to enabling SNP. + */ + on_each_cpu(mfd_enable, NULL, 1); + + on_each_cpu(snp_enable, NULL, 1); +} +EXPORT_SYMBOL_FOR_MODULES(snp_prepare_for_snp_init, "ccp"); + /* * Do the necessary preparations which are verified by the firmware as * described in the SNP_INIT_EX firmware command description in the SNP @@ -510,8 +534,6 @@ static bool __init setup_rmptable(void) */ int __init snp_rmptable_init(void) { - u64 val; - if (WARN_ON_ONCE(!cc_platform_has(CC_ATTR_HOST_SEV_SNP))) return -ENOSYS; =20 @@ -521,22 +543,8 @@ int __init snp_rmptable_init(void) if (!setup_rmptable()) return -ENOSYS; =20 - /* - * Check if SEV-SNP is already enabled, this can happen in case of - * kexec boot. - */ - rdmsrq(MSR_AMD64_SYSCFG, val); - if (val & MSR_AMD64_SYSCFG_SNP_EN) - goto skip_enable; - - snp_clear_rmp(); - - /* MtrrFixDramModEn must be enabled on all the CPUs prior to enabling SNP= . */ - on_each_cpu(mfd_enable, NULL, 1); - - on_each_cpu(snp_enable, NULL, 1); + snp_prepare_for_snp_init(); =20 -skip_enable: /* * Setting crash_kexec_post_notifiers to 'true' to ensure that SNP panic * notifier is invoked to do SNP IOMMU shutdown before kdump. --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 5C964346FA0; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="th8gNFul" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF19AC4CEF7; Mon, 9 Mar 2026 18:01:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079287; bh=4Z1AlcExpcYxtxDtwE2OqAaS1Hmy/ko7Xoe4DEuuMnA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=th8gNFuliiQwjJDlMsBwTM15Zs5b1XlEeTPw+pxn49nIXoxmfcOAVj4AryI4vuzpf LdtPKhyX4wuTAk/AAw8lpAJ9ocymCSR30nTTqZucjPhRtMMUZHTmVmR9yBz5y8Zrii CiR3UFSFFREzaXFW5Yor8H8pbR/zSb+EpjeZVbV7u+uvdkW/K+5G7vplCePMgJKpyj MYPe5xyeBBn31b8WC0gfKf2ZSZT/lhnInkmN7eA4gONk289jI4yGOXbNm5W7oIWaai pHUUROoXCQYOhvpU8QMJu7hplfuoLi7wJYXVigJb7za4Nw7EyjJXqjkOs8CKVC1WUv LZfT5sI8Ic/og== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 06/10] x86/snp, crypto: move SNP init to ccp driver Date: Mon, 9 Mar 2026 12:00:48 -0600 Message-ID: <20260309180053.2389118-7-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" Use the new snp_prepare_for_snp_init() to initialize SNP from the ccp driver instead of at boot time. This means that SNP is not enabled unless it is really going to be used (i.e. kvm_amd loads the ccp driver automatically). Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/virt/svm/sev.c | 2 -- drivers/crypto/ccp/sev-dev.c | 2 ++ 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index 9d2cddbeaf21..28d240484453 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -543,8 +543,6 @@ int __init snp_rmptable_init(void) if (!setup_rmptable()) return -ENOSYS; =20 - snp_prepare_for_snp_init(); - /* * Setting crash_kexec_post_notifiers to 'true' to ensure that SNP panic * notifier is invoked to do SNP IOMMU shutdown before kdump. diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 8b2dfc11289b..07c4736a1f0a 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -1373,6 +1373,8 @@ static int __sev_snp_init_locked(int *error, unsigned= int max_snp_asid) return -EOPNOTSUPP; } =20 + snp_prepare_for_snp_init(); + /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */ on_each_cpu(snp_set_hsave_pa, NULL, 1); =20 --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9136D347FC4; Mon, 9 Mar 2026 18:01:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079289; cv=none; b=glSZ/TkH6cbA+sDt+aZMKMCd0DVjmLBiEPSJIWDBxWzkYuQq5o2bpNaVWjnp1c8ocD2GxUJ/B2qSxMouyi0aCuK2UyxUT0YrS/YnnrR+vp5e4B5IR49y2pz1xWofMLbx/2ShKG8cNefBbwqBiUtFrxDKkHwz8xaF1GlKVyBQ/8M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079289; c=relaxed/simple; bh=8+eedZkuRiiEx+AHpOUJiKJ97lwbA6RpN02/poBXrwY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=p/mVSmfZZ97SgyKAC4cLRkLwI8j9rCRE/8VG6eemS8SMBMV3TZcbCJNy/BYM8PUxmOFrYm+hR4t0I9yhC2RvQ3jRCvVqoxZVy3z1xUyRQPoWzXt14MRYN4AwVnCF2Jz7Jsjg2hEAuEJktDAAgL271fYmXVB1hASrXR0MbFhHhNU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LWJzZqYk; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LWJzZqYk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FB17C2BCB0; Mon, 9 Mar 2026 18:01:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079289; bh=8+eedZkuRiiEx+AHpOUJiKJ97lwbA6RpN02/poBXrwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LWJzZqYkmkwM+e8qE0UHdB6Fjxft03Sq5NdnveJzD5yOqA+gwBeP6Bd5w6hRfqqKQ sL9qI6ah+N5DDwCQSguWLieyjXk1kAUr5ZoW79egF5JPZF4nmvE3DoIY6QpWqc5Rax MU0yxMgF1m2rUrMKlnsk7e8lgE8kKe+N07gf1toDtBVcVgOUjdOvzWWzhLJrDrRq/Q 2n4VlVoqKY45ywvCHlVHgcvQlgfkc5kjXO8TPeXIewoY4LzjH5UcZZb7Oh5vuEsOWZ /yMSX+NHRkn2KI3Jm27n16DkITwLOVuaLFpurrL4u6UEDiup1hifRiFS/oGHkF5DtT LAcPUiWng7ewA== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 07/10] x86/snp, crypto: move HSAVE_PA setup to arch/ Date: Mon, 9 Mar 2026 12:00:49 -0600 Message-ID: <20260309180053.2389118-8-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" Now that there is snp_prepare_for_snp_init() that indicates when the CCP driver wants to prepare the architecture for SNP_INIT(_EX), move this architecture-specific bit of code to a more sensible place. Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/virt/svm/sev.c | 8 ++++++++ drivers/crypto/ccp/sev-dev.c | 8 -------- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index 28d240484453..cc10d059140d 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -503,6 +503,11 @@ static bool __init setup_rmptable(void) return true; } =20 +static void snp_set_hsave_pa(void *arg) +{ + wrmsrq(MSR_VM_HSAVE_PA, 0); +} + void snp_prepare_for_snp_init(void) { u64 val; @@ -524,6 +529,9 @@ void snp_prepare_for_snp_init(void) on_each_cpu(mfd_enable, NULL, 1); =20 on_each_cpu(snp_enable, NULL, 1); + + /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */ + on_each_cpu(snp_set_hsave_pa, NULL, 1); } EXPORT_SYMBOL_FOR_MODULES(snp_prepare_for_snp_init, "ccp"); =20 diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 07c4736a1f0a..b10104f243b9 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -1076,11 +1076,6 @@ static inline int __sev_do_init_locked(int *psp_ret) return __sev_init_locked(psp_ret); } =20 -static void snp_set_hsave_pa(void *arg) -{ - wrmsrq(MSR_VM_HSAVE_PA, 0); -} - /* Hypervisor Fixed pages API interface */ static void snp_hv_fixed_pages_state_update(struct sev_device *sev, enum snp_hv_fixed_pages_state page_state) @@ -1375,9 +1370,6 @@ static int __sev_snp_init_locked(int *error, unsigned= int max_snp_asid) =20 snp_prepare_for_snp_init(); =20 - /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */ - on_each_cpu(snp_set_hsave_pa, NULL, 1); - /* * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list * of system physical address ranges to convert into HV-fixed page --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2F2C734B408; Mon, 9 Mar 2026 18:01:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079292; cv=none; b=g+urN8aBOXCcc1/4jHMTOCH6fk/vVtQsm5K7V7r+gNCcnbIJMk003guCxG43rohgSyR5k8ESSTq5LSBIA2YYMe2HN5xu8wfvw+lsNtUzV2n4twyc7GSQC93Hqt7OF9MMfCtTOrXTDglzUgs0ctjbIJPrlktLSFM4zMcZVEVMm3g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079292; c=relaxed/simple; bh=SeTaaMFQof9ylHh0W6XyzL5ZnPxEAQuaJ3T/0ofB0aE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DnI5WzzKoUKceoutIPJj8xPL98w0Rw7RVCg3wiedizHGu6puh6q4YJQBpoUXq6eelaXz3T0Sy2jcMeBW3iAXwwg/r94UPVhQguSYYTNiJUZ+p65JRsPQ+dqI4Vqn3yhctmBdDN11cHi2e5ZfFsnVjDEi+ATtic/aSt+oI9sWyAc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=smVrMKUV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="smVrMKUV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBB12C2BCB0; Mon, 9 Mar 2026 18:01:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079292; bh=SeTaaMFQof9ylHh0W6XyzL5ZnPxEAQuaJ3T/0ofB0aE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=smVrMKUVN0lv2Q6yFzcheFrz1I5M+nE6Z4fzD414kurXUXrFvyH6mtiCF2HAuqD46 4pO2hzR58CaIfHOGygpTI6jTdiPOgmZOTRuJgshhgoyD1+1QwYJ2oXZRBLoGL0AFe4 D64VwcQ8DrbcphUB4ZrUGqdlZhJJ+fJ7mRLJkgthlxZRbMCTvxpA+9DBz62StS3EoQ OA076eC5a5wqNzR235RpaQOzbpjQpq7khC4Gy1RdZ4ujiMVdAtdbOE7u/iF/kwPj1z ovRF8v7FizUio/29hWRmNPwiBujqixN2sapqhSxnbejgxJyLpbcnk+PoYdA4//oEBo B8y/solY6Hfag== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 08/10] x86/snp: create snp_x86_shutdown() Date: Mon, 9 Mar 2026 12:00:50 -0600 Message-ID: <20260309180053.2389118-9-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" After SNP_SHUTDOWN, two architecture-level things should be done: 1. clear the RMP table 2. disable MFDM to prevent the FW_WARN in k8_check_syscfg_dram_mod_en() in the event of a kexec Create and export to the CCP driver a function that does them. Also change the MFDM helper to allow for disabling the bit, since the SNP x86 shutdown path needs to disable MFDM. The comment for k8_check_syscfg_dram_mod_en() notes, the "BIOS" is supposed clear it, or the kernel in the case of module unload and shutdown followed by kexec. Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- arch/x86/include/asm/sev.h | 2 ++ arch/x86/virt/svm/sev.c | 23 ++++++++++++++++++++--- 2 files changed, 22 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index 0bcd89d4fe90..36d2b1ea19c0 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -662,6 +662,7 @@ static inline void snp_leak_pages(u64 pfn, unsigned int= pages) __snp_leak_pages(pfn, pages, true); } void snp_prepare_for_snp_init(void); +void snp_x86_shutdown(void); #else static inline bool snp_probe_rmptable_info(void) { return false; } static inline int snp_rmptable_init(void) { return -ENOSYS; } @@ -679,6 +680,7 @@ static inline void snp_leak_pages(u64 pfn, unsigned int= npages) {} static inline void kdump_sev_callback(void) { } static inline void snp_fixup_e820_tables(void) {} static inline void snp_prepare_for_snp_init(void) {} +static inline void snp_x86_shutdown(void) {} #endif =20 #endif diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c index cc10d059140d..321f3c004fbc 100644 --- a/arch/x86/virt/svm/sev.c +++ b/arch/x86/virt/svm/sev.c @@ -132,12 +132,15 @@ static unsigned long snp_nr_leaked_pages; #undef pr_fmt #define pr_fmt(fmt) "SEV-SNP: " fmt =20 -static void mfd_enable(void *arg) +static void mfd_reconfigure(void *arg) { if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return; =20 - msr_set_bit(MSR_AMD64_SYSCFG, MSR_AMD64_SYSCFG_MFDM_BIT); + if (arg) + msr_set_bit(MSR_AMD64_SYSCFG, MSR_AMD64_SYSCFG_MFDM_BIT); + else + msr_clear_bit(MSR_AMD64_SYSCFG, MSR_AMD64_SYSCFG_MFDM_BIT); } =20 static void snp_enable(void *arg) @@ -526,7 +529,7 @@ void snp_prepare_for_snp_init(void) * MtrrFixDramModEn is not shared between threads on a core, * therefore it must be set on all CPUs prior to enabling SNP. */ - on_each_cpu(mfd_enable, NULL, 1); + on_each_cpu(mfd_reconfigure, (void *)1, 1); =20 on_each_cpu(snp_enable, NULL, 1); =20 @@ -535,6 +538,20 @@ void snp_prepare_for_snp_init(void) } EXPORT_SYMBOL_FOR_MODULES(snp_prepare_for_snp_init, "ccp"); =20 +void snp_x86_shutdown(void) +{ + u64 syscfg; + + rdmsrq(MSR_AMD64_SYSCFG, syscfg); + + if (syscfg & MSR_AMD64_SYSCFG_SNP_EN) + return; + + snp_clear_rmp(); + on_each_cpu(mfd_reconfigure, 0, 1); +} +EXPORT_SYMBOL_FOR_MODULES(snp_x86_shutdown, "ccp"); + /* * Do the necessary preparations which are verified by the firmware as * described in the SNP_INIT_EX firmware command description in the SNP --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B2BA334D3B1; Mon, 9 Mar 2026 18:01:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079294; cv=none; b=GCUjmHiw4CMvKeAnGPAOEkrTMW14/8OzQWT0nJa4/rvhJ78ahXrtKTG/Ez/kFvJdedzH2k5Nt0J+amxPJ5WvxUOZF8vZyD8SDZeKDaWnQPxuwu00qVC3t+57wqjbSbIE4VrxaT8KPokHyJAM8i7579pikf05ncNn4nX7e+ASapQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079294; c=relaxed/simple; bh=+CVA3mASejU0tJVdTlEmr5PknhwxAcNa6ZiN8WZxJf8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eqYrIm0bxMGkwzhZI2atDh9/3xIvuFSqLsJotMYfkdW/Wk6PuwTYUlsgjH3sN3u1tMdot6HokMvaAjj3pW83XSjVLtg+Sd6suN9ufcGKfiR7w6z6rO3KvNVTzV7UvuhZEAhguUAl8+KjvycVLzPzWDmgzp7EhyOQ3wDxFqFp40k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P9SwTU4M; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="P9SwTU4M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 552A4C2BCAF; Mon, 9 Mar 2026 18:01:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079294; bh=+CVA3mASejU0tJVdTlEmr5PknhwxAcNa6ZiN8WZxJf8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P9SwTU4Me5kUa/H1ZRG32HJzmK22L4v1dr739dL5BEwrOxpzCVu701NVlmrg5j3jt UPnjtGotWGlznL1k5Tao+MmcGYaSNZpqzaiey/qWldQVYUqltPsV7V8DkXFUrobTw+ uVlcHze1IolCklJciox/B4wtsKNZX31AuhpODzhGc9rKkTH45BhlysYU6J5tQn7/Eb sWmnc47NspAueshDzE8CBd+ntNkqAznOby4IogAqd7ZZolOVoW3qqArcru7OAbmr1h oKJQA6X2wxgx53wyxkmzJxXXhdD/56MHNCK8NdvbylUKTATqoJKrKhM9HaPhyfjte1 8+tcpYS4kdUQw== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 09/10] crypto: ccp - implement SNP x86 shutdown Date: Mon, 9 Mar 2026 12:00:51 -0600 Message-ID: <20260309180053.2389118-10-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Tycho Andersen (AMD)" The SEV firmware has support to disable SNP during an SNP_SHUTDOWN_EX command. Verify that this support is available and set the flag so that SNP is disabled when it is not being used. In cases where SNP is disabled, skip the call to amd_iommu_snp_disable(), as all of the IOMMU pages have already been made shared. Also skip the panic case, since snp_x86_shutdown() does IPIs. Signed-off-by: Tycho Andersen (AMD) Reviewed-by: Tom Lendacky --- drivers/crypto/ccp/sev-dev.c | 41 +++++++++++++++++++++--------------- include/linux/psp-sev.h | 4 +++- 2 files changed, 27 insertions(+), 18 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index b10104f243b9..be6f3720e929 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -2039,6 +2039,8 @@ static int __sev_snp_shutdown_locked(int *error, bool= panic) memset(&data, 0, sizeof(data)); data.len =3D sizeof(data); data.iommu_snp_shutdown =3D 1; + if (sev->snp_feat_info_0.ecx & SNP_X86_SHUTDOWN_SUPPORTED) + data.x86_snp_shutdown =3D 1; =20 /* * If invoked during panic handling, local interrupts are disabled @@ -2072,23 +2074,28 @@ static int __sev_snp_shutdown_locked(int *error, bo= ol panic) return ret; } =20 - /* - * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP - * enforcement by the IOMMU and also transitions all pages - * associated with the IOMMU to the Reclaim state. - * Firmware was transitioning the IOMMU pages to Hypervisor state - * before version 1.53. But, accounting for the number of assigned - * 4kB pages in a 2M page was done incorrectly by not transitioning - * to the Reclaim state. This resulted in RMP #PF when later accessing - * the 2M page containing those pages during kexec boot. Hence, the - * firmware now transitions these pages to Reclaim state and hypervisor - * needs to transition these pages to shared state. SNP Firmware - * version 1.53 and above are needed for kexec boot. - */ - ret =3D amd_iommu_snp_disable(); - if (ret) { - dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); - return ret; + if (data.x86_snp_shutdown) { + if (!panic) + snp_x86_shutdown(); + } else { + /* + * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP + * enforcement by the IOMMU and also transitions all pages + * associated with the IOMMU to the Reclaim state. + * Firmware was transitioning the IOMMU pages to Hypervisor state + * before version 1.53. But, accounting for the number of assigned + * 4kB pages in a 2M page was done incorrectly by not transitioning + * to the Reclaim state. This resulted in RMP #PF when later accessing + * the 2M page containing those pages during kexec boot. Hence, the + * firmware now transitions these pages to Reclaim state and hypervisor + * needs to transition these pages to shared state. SNP Firmware + * version 1.53 and above are needed for kexec boot. + */ + ret =3D amd_iommu_snp_disable(); + if (ret) { + dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); + return ret; + } } =20 snp_leak_hv_fixed_pages(); diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h index 69ffa4b4d1fa..2adb990189c1 100644 --- a/include/linux/psp-sev.h +++ b/include/linux/psp-sev.h @@ -834,7 +834,8 @@ struct sev_data_range_list { struct sev_data_snp_shutdown_ex { u32 len; u32 iommu_snp_shutdown:1; - u32 rsvd1:31; + u32 x86_snp_shutdown:1; + u32 rsvd1:30; } __packed; =20 /** @@ -891,6 +892,7 @@ struct snp_feature_info { } __packed; =20 /* Feature bits in ECX */ +#define SNP_X86_SHUTDOWN_SUPPORTED BIT(1) #define SNP_RAPL_DISABLE_SUPPORTED BIT(2) #define SNP_CIPHER_TEXT_HIDING_SUPPORTED BIT(3) #define SNP_AES_256_XTS_POLICY_SUPPORTED BIT(4) --=20 2.53.0 From nobody Thu Apr 9 09:35:25 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 269A23E9F88; Mon, 9 Mar 2026 18:01:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079297; cv=none; b=BWcxnQEHHvvv5Bmq46CW677DMUkEsTVzfSCLUcKcGCDVvmx4meGoYMfBpbVjk12RPNLapt8e2nToV9jtbuv5Ygpdbs3X8Y+jgLnwgXUakfJYvRNorTxTetRjxjLKwj4AG5PG5oXBWM2Rr95whfWh6B7lfmhlVEOXJGTpzCIaMvw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773079297; c=relaxed/simple; bh=4qhPs0u0MDTJre/3DNAo+CNY3QBGUHi6CuPNrOVlC7k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lKRUuUqZowT8i10T2wp5PlN5yr6XrvVtMDWwAbC4a6ojt8TaT774NAr8Wc6plT2k4Bh/frz6Oippjxn4JusDCVoa3Wks9vg29oTmDqeeK/V1CoLRLNL0vVelAxnRx7nK5O1AVFeCuT59SFKp6/I4hGSH7T03JvqrwK9XRTnraeA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LTF5wN4n; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LTF5wN4n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DAC83C4CEF7; Mon, 9 Mar 2026 18:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773079297; bh=4qhPs0u0MDTJre/3DNAo+CNY3QBGUHi6CuPNrOVlC7k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LTF5wN4nv/R6vnU5SNiOJAuYHqPuFenFPM9l9/fFxiuQR5DRQqkSD5lnARifIAvs2 Qp294vBqwa1EdJTCVEI3xSR1njo0PuV9nJSjmbc4CdJFldNheEwEhCLz8vhCZP9mex d7nRGYdHXQgl7LCLZaL4ShlP+ECgqvtwm2YDibGa94gZhjw0MOq+8jXpC4PoYOuEVV qn8fQbkiap9uUHEvDs7SauxcwBmCNmPQktG0YfUdbFbtRrTmv9btjDxN6RpGYst6Gt OrO9Q1LCHa5FdxhlaWfFEw6w+oB/bzigBz5O9yRRPfde/WNw2SxXjttyswSz+UPLbn s8swQNSFYQFWA== From: Tycho Andersen To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ashish Kalra , Tom Lendacky , John Allen , Herbert Xu , "David S. Miller" , Ard Biesheuvel , Neeraj Upadhyay , Kishon Vijay Abraham I , Alexey Kardashevskiy , Nikunj A Dadhania , "Peter Zijlstra (Intel)" , Kim Phillips , Sean Christopherson Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: [PATCH v2 10/10] crypto: ccp - Update HV_FIXED page states to allow freeing of memory Date: Mon, 9 Mar 2026 12:00:52 -0600 Message-ID: <20260309180053.2389118-11-tycho@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260309180053.2389118-1-tycho@kernel.org> References: <20260306153846.GKaar1Bg_1EKm17tXJ@fat_crate.local> <20260309180053.2389118-1-tycho@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Tom Lendacky After SNP is disabled, any pages allocated as HV_FIXED can now be freed. Update the page state of these pages and the snp_leak_hv_fixed_pages() function to free pages on SNP_SHUTDOWN. Signed-off-by: Tom Lendacky Signed-off-by: Tycho Andersen (AMD) --- drivers/crypto/ccp/sev-dev.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index be6f3720e929..eac1181c2f6a 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -1219,7 +1219,7 @@ static void snp_add_hv_fixed_pages(struct sev_device = *sev, struct sev_data_range =20 static void snp_leak_hv_fixed_pages(void) { - struct snp_hv_fixed_pages_entry *entry; + struct snp_hv_fixed_pages_entry *entry, *nentry; =20 /* List is protected by sev_cmd_mutex */ lockdep_assert_held(&sev_cmd_mutex); @@ -1227,10 +1227,16 @@ static void snp_leak_hv_fixed_pages(void) if (list_empty(&snp_hv_fixed_pages)) return; =20 - list_for_each_entry(entry, &snp_hv_fixed_pages, list) - if (entry->page_state =3D=3D HV_FIXED) + list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) { + if (entry->free && entry->page_state !=3D HV_FIXED) + __free_pages(entry->page, entry->order); + else __snp_leak_pages(page_to_pfn(entry->page), 1 << entry->order, false); + + list_del(&entry->list); + kfree(entry); + } } =20 bool sev_is_snp_ciphertext_hiding_supported(void) @@ -2077,6 +2083,7 @@ static int __sev_snp_shutdown_locked(int *error, bool= panic) if (data.x86_snp_shutdown) { if (!panic) snp_x86_shutdown(); + snp_hv_fixed_pages_state_update(sev, ALLOCATED); } else { /* * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP --=20 2.53.0