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X-CSE-ConnectionGUID: GYkJ7b4VQq2prk7ZNXH9lQ== X-CSE-MsgGUID: aLgeL+ZNQIaU5m3XfnsAkQ== X-IronPort-AV: E=McAfee;i="6800,10657,11696"; a="70777384" X-IronPort-AV: E=Sophos;i="6.21,282,1763452800"; d="scan'208";a="70777384" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Feb 2026 07:14:40 -0800 X-CSE-ConnectionGUID: oyqDdiqBR6iTuxNs47FnUQ== X-CSE-MsgGUID: YfQyH9TxRhCEvG8dj486og== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,282,1763452800"; d="scan'208";a="249244440" Received: from dwesterg-mobl1.amr.corp.intel.com (HELO [10.125.111.231]) ([10.125.111.231]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Feb 2026 07:14:39 -0800 Message-ID: Date: Mon, 9 Feb 2026 07:14:38 -0800 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1] x86/smp: Set up exception handling before cr4_init() To: Xin Li , Sohil Mehta Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, peterz@infradead.org, andrew.cooper3@citrix.com, nikunj@amd.com, thomas.lendacky@amd.com, seanjc@google.com, stable@vger.kernel.org References: <20260206185035.1250577-1-xin@zytor.com> <37de06e1-aae4-4ebd-ac93-1846ee4cd91e@intel.com> <5E3DA211-BD18-459F-ADDE-63E24E8C8BEA@zytor.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 8bit On 2/9/26 00:16, Xin Li wrote: > Iā€™m not sure if Dave also wants to make BSP/AP boot code symmetric > at the same time šŸ˜‰ It's perfectly fine to do things one bit at a time. In this case, cr4_init() is does two different things underneath the covers depending on the state of CR pinning. If CR pinning as a feature is kicked out influencing the early CPU boot code at _all_, then it certainly helps the goal if making the AP/BSP code more symmetric. So I very much prefer doing things one bit at a time, if we can.