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a="3074669" X-IronPort-AV: E=Sophos;i="6.27,208,1787036400"; d="scan'208";a="3074669" Received: from fmviesa013.fm.intel.com ([10.60.135.153]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Nov 2026 07:06:45 -0800 X-CSE-ConnectionGUID: hKymEkfQSTK29OQ/BmWb5A== X-CSE-MsgGUID: r3SNnBh4QJeOVF4+0Ksjwg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,208,1787036400"; d="scan'208";a="10307682" Received: from iherna2-mobl4.amr.corp.intel.com (HELO [10.125.111.125]) ([10.125.111.125]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Nov 2026 07:06:43 -0800 Message-ID: Date: Wed, 11 Nov 2026 07:06:41 -0800 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] x86/sgx: Skip EPC initialization in the kdump kernel To: Yuanhe Shu , jarkko@kernel.org, dave.hansen@linux.intel.com, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, hpa@zytor.com Cc: x86@kernel.org, linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, challvy.tee@gmail.com References: <20261111123942.3842771-1-xiangzao@linux.alibaba.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/11/26 04:39, Yuanhe Shu wrote: > + /* The kdump kernel has no use for SGX. Skip it. */ > + if (is_kdump_kernel()) > + return -ENODEV; I'd much rather this be inverted: have the kdump code maintain a list of things it needs to turn off rather than sprinkle is_kdump_kernel() around any further. I'd suggest a small bit of kdump specific code that does: setup_clear_cpu_cap(X86_FEATURE_SGX); It'll need to be in x86 code or under an x86 #ifdef.