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Bae" , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Thomas Gleixner , Dave Hansen , Ian Rogers , Adrian Hunter , Jiri Olsa , Alexander Shishkin , Andi Kleen , Eranian Stephane Cc: Mark Rutland , broonie@kernel.org, Ravi Bangoria , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Zide Chen , Falcon Thomas , Dapeng Mi , Xudong Hao References: <20260209072047.2180332-1-dapeng1.mi@linux.intel.com> <20260209072047.2180332-9-dapeng1.mi@linux.intel.com> <5c3ea318-4543-42a4-9b81-7a1da0b8bed1@intel.com> Content-Language: en-US From: "Mi, Dapeng" In-Reply-To: <5c3ea318-4543-42a4-9b81-7a1da0b8bed1@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/12/2026 3:39 AM, Chang S. Bae wrote: > On 2/8/2026 11:20 PM, Dapeng Mi wrote: >> Ensure that the TIF_NEED_FPU_LOAD flag is always set after saving the >> FPU state. This guarantees that the user space FPU state has been saved >> whenever the TIF_NEED_FPU_LOAD flag is set. >> >> A subsequent patch will verify if the user space FPU state can be >> retrieved from the saved task FPU state in the NMI context by checking >> the TIF_NEED_FPU_LOAD flag. >> >> Suggested-by: Peter Zijlstra >> Suggested-by: Dave Hansen > I could check some previous discussions there: > https://lore.kernel.org/all/20251204151735.GO2528459@noisy.programming.kicks-ass.net/ > > With that, I think I can get the context of this change -- tightening > the flag up with the buffer against *NMIs*. > > But the changelog doesn't look clear enough to explain the reason to me. > > At least, I guess Links to the past discussions provides better context > to readers. Thanks for the reminding. I would add a "Closes" tag here.