From mboxrd@z Thu Jan 1 00:00:00 1970 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 C562B2F44 for ; Sat, 31 Dec 2022 15:32:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA2EBC433EF; Sat, 31 Dec 2022 15:32:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672500764; bh=biJ5OjRTz8LacHCIRhDE4EhKtGxMPJqMl2cws+KriSA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Wy3CUR+9dYkvysDD2MX1mxUzbtSCU/1qo0R11/dbrhUE7qsa8wF81yuG3/xCMFGjR FB8Fxq6+YD3el2KrtlkHXbtmFLVuRa0Z2Cfcg0s9cShsI7kUFfOhS7S1dKNWfTCcH+ QJVr1h0R9wajCAdbrdjrha9+ESNbIlyTnPRIqs94qHVTvYmruLISpbyFQVD6eUgLvU UQX0sXD+UyHjOqhlWBnrlSIJAx5rNV8SLwvq7fdR9UDaHZjj67k8/uzTPAqrWulycx ZJnOrGgBUmTEiIP3SnCaMARWF0J7NZkLd5NPuJ0Va6hbCtWXtS0sSOvq3VRcnvS8a7 zSQw+OnHg/f+w== Date: Sat, 31 Dec 2022 15:32:42 +0000 From: Jarkko Sakkinen To: Michael Roth Cc: kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, jroedel@suse.de, thomas.lendacky@amd.com, hpa@zytor.com, ardb@kernel.org, pbonzini@redhat.com, seanjc@google.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, luto@kernel.org, dave.hansen@linux.intel.com, slp@redhat.com, pgonda@google.com, peterz@infradead.org, srinivas.pandruvada@linux.intel.com, rientjes@google.com, dovmurik@linux.ibm.com, tobin@ibm.com, bp@alien8.de, vbabka@suse.cz, kirill@shutemov.name, ak@linux.intel.com, tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com, alpergun@google.com, dgilbert@redhat.com, ashish.kalra@amd.com, harald@profian.com, Brijesh Singh Subject: Re: [PATCH RFC v7 25/64] crypto: ccp: Add support to initialize the AMD-SP for SEV-SNP Message-ID: References: <20221214194056.161492-1-michael.roth@amd.com> <20221214194056.161492-26-michael.roth@amd.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221214194056.161492-26-michael.roth@amd.com> On Wed, Dec 14, 2022 at 01:40:17PM -0600, Michael Roth wrote: > From: Brijesh Singh > > Before SNP VMs can be launched, the platform must be appropriately > configured and initialized. Platform initialization is accomplished via > the SNP_INIT command. Make sure to do a WBINVD and issue DF_FLUSH > command to prepare for the first SNP guest launch after INIT. > > During the execution of SNP_INIT command, the firmware configures > and enables SNP security policy enforcement in many system components. > Some system components write to regions of memory reserved by early > x86 firmware (e.g. UEFI). Other system components write to regions > provided by the operation system, hypervisor, or x86 firmware. > Such system components can only write to HV-fixed pages or Default > pages. They will error when attempting to write to other page states > after SNP_INIT enables their SNP enforcement. > > Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list of > system physical address ranges to convert into the HV-fixed page states > during the RMP initialization. If INIT_RMP is 1, hypervisors should > provide all system physical address ranges that the hypervisor will > never assign to a guest until the next RMP re-initialization. > For instance, the memory that UEFI reserves should be included in the > range list. This allows system components that occasionally write to > memory (e.g. logging to UEFI reserved regions) to not fail due to > RMP initialization and SNP enablement. > > Co-developed-by: Ashish Kalra > Signed-off-by: Ashish Kalra > Signed-off-by: Brijesh Singh > Signed-off-by: Michael Roth > --- > drivers/crypto/ccp/sev-dev.c | 225 +++++++++++++++++++++++++++++++++++ > drivers/crypto/ccp/sev-dev.h | 2 + > include/linux/psp-sev.h | 17 +++ > 3 files changed, 244 insertions(+) > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > index 9d84720a41d7..af20420bd6c2 100644 > --- a/drivers/crypto/ccp/sev-dev.c > +++ b/drivers/crypto/ccp/sev-dev.c > @@ -26,6 +26,7 @@ > #include > > #include > +#include > > #include "psp-dev.h" > #include "sev-dev.h" > @@ -34,6 +35,10 @@ > #define SEV_FW_FILE "amd/sev.fw" > #define SEV_FW_NAME_SIZE 64 > > +/* Minimum firmware version required for the SEV-SNP support */ > +#define SNP_MIN_API_MAJOR 1 > +#define SNP_MIN_API_MINOR 51 > + > static DEFINE_MUTEX(sev_cmd_mutex); > static struct sev_misc_dev *misc_dev; > > @@ -76,6 +81,13 @@ static void *sev_es_tmr; > #define NV_LENGTH (32 * 1024) > static void *sev_init_ex_buffer; > > +/* > + * SEV_DATA_RANGE_LIST: > + * Array containing range of pages that firmware transitions to HV-fixed > + * page state. > + */ > +struct sev_data_range_list *snp_range_list; > + > static inline bool sev_version_greater_or_equal(u8 maj, u8 min) > { > struct sev_device *sev = psp_master->sev_data; > @@ -830,6 +842,186 @@ static int sev_update_firmware(struct device *dev) > return ret; > } > > +static void snp_set_hsave_pa(void *arg) > +{ > + wrmsrl(MSR_VM_HSAVE_PA, 0); > +} > + > +static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) > +{ > + struct sev_data_range_list *range_list = arg; > + struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; > + size_t size; > + > + if ((range_list->num_elements * sizeof(struct sev_data_range) + > + sizeof(struct sev_data_range_list)) > PAGE_SIZE) > + return -E2BIG; > + > + switch (rs->desc) { > + case E820_TYPE_RESERVED: > + case E820_TYPE_PMEM: > + case E820_TYPE_ACPI: > + range->base = rs->start & PAGE_MASK; > + size = (rs->end + 1) - rs->start; > + range->page_count = size >> PAGE_SHIFT; > + range_list->num_elements++; > + break; > + default: > + break; > + } > + > + return 0; > +} > + > +static int __sev_snp_init_locked(int *error) > +{ > + struct psp_device *psp = psp_master; > + struct sev_data_snp_init_ex data; > + struct sev_device *sev; > + int rc = 0; > + > + if (!psp || !psp->sev_data) > + return -ENODEV; > + > + sev = psp->sev_data; > + > + if (sev->snp_initialized) > + return 0; Shouldn't this follow this check: if (sev->state == SEV_STATE_INIT) { /* debug printk about possible incorrect call order */ return -ENODEV; } It is game over for SNP, if SEV_CMD_INIT{_EX} got first, which means that this should not proceed. BR, Jarkko