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Peter Anvin" , Ingo Molnar , Jon Kohler , Pawan Gupta , "Peter Zijlstra (Intel)" , Thomas Gleixner , Tony Luck , x86@kernel.org Subject: Re: [PATCH 4/6] x86/cpu: Add platform ID to CPU info structure Message-ID: References: <20260119195047.86E3C696@davehans-spike.ostc.intel.com> <20260119195055.0B00B57E@davehans-spike.ostc.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo On Tue, Jan 20, 2026 at 07:06:56AM -0800, Dave Hansen wrote: > On 1/20/26 00:27, Andy Shevchenko wrote: > ... > >> Note: This should not grow the size of 'struct cpuinfo_x86' in > >> practice since the u8 fits next to another u8 in the structure. > > > > Have you run `pahole` to confirm? > > I have not. If you'd like to contribute to the series by compiling this > and running pahole on it, I'd very much appreciate it! Okay, here is the diff: --- old 2026-01-20 21:40:39.170530703 +0100 +++ new 2026-01-20 21:37:42.717138133 +0100 @@ -19,8 +19,9 @@ }; __u8 x86_stepping; /* 4 1 */ + __u8 x86_platform_id; /* 5 1 */ - /* XXX 3 bytes hole, try to pack */ + /* XXX 2 bytes hole, try to pack */ int x86_tlbsize; /* 8 4 */ __u32 vmx_capability[5]; /* 12 20 */ @@ -75,8 +76,8 @@ unsigned int initialized:1; /* 332: 8 4 */ - /* size: 336, cachelines: 6, members: 27 */ - /* sum members: 319, holes: 5, sum holes: 14 */ + /* size: 336, cachelines: 6, members: 28 */ + /* sum members: 320, holes: 5, sum holes: 13 */ /* sum bitfield members: 1 bits (0 bytes) */ /* bit_padding: 23 bits */ /* last cacheline: 16 bytes */ -- With Best Regards, Andy Shevchenko