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bh=C2v1Wl1TRZDwC2MEfD4XkkqLj3ach0DgED2G6BUaXlw=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=NmRJUwFgZZC9DACntO8r1lgEBhd912ClirOcmmDyj/JQi5tp73BjqXfM9cLBU+Atw +2fPhkxGU6bPe79V4S/tF5oOaKzBoY7kCM8N4ahdp8HNZ9D0OsJmV9FKZUUQFzZuIl tFvz9kZ2rsV/VbYJdWrqKka2yMzemUUBAgfGE0KabYlEct9NCyKW2fngH520FXUdep 06DhnN75hfFy4xOIv8DWELNg/T8AsE2u+vRsO3ynjetMRjsNo4WyMWhuT1at40Sq6q 0t+OmTPOuj3dlqXKraxlcUfh1sJu2MCTCLS19nQ4mdSLehU0jO0gr6C7/RTB6eIj/u VZ69XOEEU+R/w== Message-ID: <7a5a28a3-baf4-4915-8585-eae8cd323895@zytor.com> Date: Wed, 8 Oct 2025 07:16:28 +0800 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 01/15] x86/cpu: Enumerate the LASS feature bits To: Sohil Mehta , "Edgecombe, Rick P" , "tglx@linutronix.de" , "mingo@redhat.com" , "bp@alien8.de" , "x86@kernel.org" , "dave.hansen@linux.intel.com" Cc: "corbet@lwn.net" , "ardb@kernel.org" , "david.laight.linux@gmail.com" , "luto@kernel.org" , "jpoimboe@kernel.org" , "andrew.cooper3@citrix.com" , "Luck, Tony" , "alexander.shishkin@linux.intel.com" , "kas@kernel.org" , "seanjc@google.com" , "rdunlap@infradead.org" , "dwmw@amazon.co.uk" , "vegard.nossum@oracle.com" , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , "kees@kernel.org" , "hpa@zytor.com" , "peterz@infradead.org" , "linux-efi@vger.kernel.org" , "geert@linux-m68k.org" References: <20251007065119.148605-1-sohil.mehta@intel.com> <20251007065119.148605-2-sohil.mehta@intel.com> <47fb7efd89698f46a305ca446d0e4471d1f24fbb.camel@intel.com> Content-Language: en-US From: Xin Li Autocrypt: addr=xin@zytor.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/8/2025 4:49 AM, Sohil Mehta wrote: >>> >>> +config X86_DISABLED_FEATURE_LASS >>> + def_bool y >>> + depends on X86_32 >>> + >> All the other ones in the file are !X86_64. Why do this one X86_32? >> > The double negation (DISABLED and !X86_64) was harder to follow when > this was initially posted. > > https://lore.kernel.org/lkml/73796800-819b-4433-b0ef-db852336d7a4@zytor.com/ > https://lore.kernel.org/lkml/756e93a2-7e42-4323-ae21- > a5437e71148e@infradead.org/ > > I don't have a strong preference. I guess the inconsistency makes it > confusing as well. Will change it back to !X86_64 unless Xin objects. I prefer to use X86_32, which is more direct. Now the only disabled feature when !X86_64 is X86_DISABLED_FEATURE_PCID. And I would expect the disabled features due to lack of 32-bit enabling will keep growing until we remove 32-bit kernel code. I was also thinking to move all such disabled features to a dedicated file when the total reaches 3. But hopefully removing 32-bit will happen first.