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Wysocki" , Peter Zijlstra , David Hildenbrand , Michal Hocko , Jonathan Corbet , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , len brown , pavel machek , Kees Cook , Andrew Morton , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Catalin Marinas , Nico Pache , xu xin , wangfushuai , Andrii Nakryiko , Christian Brauner , Thomas Gleixner , Jeff Layton , Al Viro , Adrian Ratiu , linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250807121418.139765-1-zhangzihuan@kylinos.cn> <20250807121418.139765-7-zhangzihuan@kylinos.cn> <20250808142948.GA21685@redhat.com> From: Zihuan Zhang In-Reply-To: <20250808142948.GA21685@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Stat-Signature: wak8h1nnbgh3s5t1qiu1oh5mx9zn4my3 X-Rspamd-Queue-Id: 23E2B4000D X-Rspamd-Server: rspam10 X-Rspam-User: X-HE-Tag: 1754986055-307140 X-HE-Meta: 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 D5YlY5dA ZKNCrDWnmSWofq+3UoP/UQvGk36xK5sAxWL3PCveBR5AALtcSoQ8GD65yRIRiZZICbgEj93sloIzbvf0oSO9sBmlOu3kuT7xaOkHuSxglfIRz11PpM18YAM0VWZZamamd/DEn92JXIhIAko4= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: =E5=9C=A8 2025/8/8 22:29, Oleg Nesterov =E5=86=99=E9=81=93: > On 08/07, Zihuan Zhang wrote: >> @@ -6980,6 +6981,7 @@ void __noreturn do_task_dead(void) >> current->flags |=3D PF_NOFREEZE; >> >> __schedule(SM_NONE); >> + freeze_set_default_priority(current, FREEZE_PRIORITY_NEVER); >> BUG(); > But this change has no effect? > > Firstly, this last __schedule() should not return, note the BUG() we ha= ve. > > Secondly, this zombie is already PF_NOFREEZE, freeze_task() will return > false anyway. Thanks for pointing that out. Indeed, I=E2=80=99ve noticed that in the current position the code has no= effect. If we move this code to a more appropriate place, it should improve both=20 safety and usefulness compared to the previous implementation. > Oleg. >