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X-CSE-ConnectionGUID: 4FyRkkz9R+CPyNQrBkoJTw== X-CSE-MsgGUID: 5xjpyESLQSe/4R4vhxsgFQ== X-IronPort-AV: E=McAfee;i="6800,10657,11780"; a="78954645" X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="78954645" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 09:34:38 -0700 X-CSE-ConnectionGUID: T/Sf9Od0RFK23fC36ZXpZw== X-CSE-MsgGUID: yFZXbJ/PTk2aqSpbHKQ01Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="232285968" Received: from dnelso2-mobl.amr.corp.intel.com (HELO [10.125.111.18]) ([10.125.111.18]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 09:34:37 -0700 Message-ID: <85cb14e7-403b-46fa-9e7d-819fef8d5a6d@intel.com> Date: Fri, 8 May 2026 09:34:43 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] x86/shstk: Provide kernel command line knob to disable To: Mathias Krause , "Edgecombe, Rick P" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "peterz@infradead.org" , "x86@kernel.org" , "mingo@redhat.com" , "tglx@kernel.org" Cc: "linux-kernel@vger.kernel.org" , "Gao, Chao" References: <20260402173606.1096172-1-minipli@grsecurity.net> <3d7c8d26-558d-40ef-9ad9-3a5100eed9e5@grsecurity.net> <739e4dd0-84a3-4b37-8cc3-b7ec59737010@intel.com> <4cffee5d2886129e621d3011db1d00a236869d1d.camel@intel.com> <457a77eb-2a77-4873-b2a1-24f5110a0393@grsecurity.net> <5b605463-533f-46ae-833a-b6c8f9bcfae1@grsecurity.net> 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 5/8/26 00:23, Mathias Krause wrote: > For *me*, 'clearcpuid=shstk,ibt' would be sufficient for my debugging > needs. It's just a question if there's more demand beside some random > kernel hacker needing a knob to disable potential problematic features, > i.e. do we expect actual *end users* having a need to fully disable CET > shadow stacks too? Last I checked, end users aren't frequently in the business of editing the kernel command line to turn off CPU features. Maybe once in a blue moon to work around bugs. But those folks can live with taint until they get fixes.