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Shutemov" , Andi Kleen , tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH Part1 v5 17/38] x86/mm: Add support to validate memory when changing C-bit To: Borislav Petkov References: <20210820151933.22401-1-brijesh.singh@amd.com> <20210820151933.22401-18-brijesh.singh@amd.com> From: Brijesh Singh Message-ID: Date: Wed, 25 Aug 2021 08:54:31 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SN4PR0501CA0126.namprd05.prod.outlook.com (2603:10b6:803:42::43) To SN6PR12MB2718.namprd12.prod.outlook.com (2603:10b6:805:6f::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [10.236.31.95] (165.204.77.1) by SN4PR0501CA0126.namprd05.prod.outlook.com (2603:10b6:803:42::43) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4457.9 via Frontend Transport; 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>> + struct snp_psc_desc *desc; >> + >> + vaddr = vaddr & PAGE_MASK; >> + vaddr_end = vaddr + (npages << PAGE_SHIFT); >> + >> + desc = kmalloc(sizeof(*desc), GFP_KERNEL_ACCOUNT); > > And again, from previous review: > > kzalloc() so that you don't have to memset() later in > __set_page_state(). > I replied to your previous comment. Depending on the npages value, the __set_page_state() will be called multiple times and on each call it needs to clear desc before populate it. So, I do not see strong reason to use kzalloc() during the desc allocation. I thought you were okay with that explanation. >> + if (!desc) >> + panic("SEV-SNP: failed to alloc memory for PSC descriptor\n"); > > "allocate" fits just fine too. > Noted. thanks