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X-CSE-ConnectionGUID: P7k8rZX8Qiis1I1FF0eT/w== X-CSE-MsgGUID: P21ne0veTe2ZMSURNVQJmA== X-IronPort-AV: E=McAfee;i="6800,10657,11765"; a="77631183" X-IronPort-AV: E=Sophos;i="6.23,194,1770624000"; d="scan'208";a="77631183" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Apr 2026 08:12:15 -0700 X-CSE-ConnectionGUID: Bpkn9GodSlOPOVfqLpwu4Q== X-CSE-MsgGUID: n9JY5e0rRne9F/MAdW0G1g== X-ExtLoop1: 1 Received: from aduenasd-mobl5.amr.corp.intel.com (HELO [10.125.108.10]) ([10.125.108.10]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Apr 2026 08:12:15 -0700 Message-ID: Date: Thu, 23 Apr 2026 08:12:08 -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 1/2] x86/bug: Add printf() validation to HAVE_ARCH_BUG_FORMAT_ARGS WARNs To: Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org Cc: linux-kernel@vger.kernel.org, Yan Zhao , Peter Zijlstra References: <20260423145419.459988-1-seanjc@google.com> <20260423145419.459988-2-seanjc@google.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 4/23/26 07:54, Sean Christopherson wrote: > Lack of validation is especially problematic for code that is 64-bit-only, > as blatant goofs can easily go unnoticed, as they (somewhat ironically) > will only be noticed by CONFIG_BUG=n builds. This took me a minute to piece together. CONFIG_BUG=n builds use the asm-generic/bug.h implementations which have: no_printk(format); and do their own printk validation. Right? Also, what do you mean about 64-bit-only code? I'm also debating if we should stick these in x86/urgent and get them to Linus sooner rather than later so folks aren't bitten by this for a whole development cycle.