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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: CC52D14000A X-Stat-Signature: 1r1iztw9izdz5up17o1ntmdns8wxnr3o X-Rspam-User: X-HE-Tag: 1748870376-304938 X-HE-Meta: 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 g058HOwy qOKAOTtoePIH5/9d4aaLL2o6Ugl3YThLmKCRMCH/m6pzPkssJL+HYnS4JDJdwtknCrjK+hEjVQrJwNo5uti92FRDTUp/mhoovHQ5husgjtkCx5xOV9JW49BD92YU96CaoHQOaNyWUDmmoFyF2+1gpzlk802hIddPkDzAgJAsMfH7NAOb36do7oOlYFHmx0dosDTU1m05DaqZTniYf10fDY3+76MKbEYr8RapX9334KmgvRsJfguA7tsjqK4Dr3NwknJ0INOYLHR75Wg4RNDmTJhHu0HH7mo82XUZ7ok5SNcpCGm2ngTUuAo4BX5CQQcNLu/NSryup0Sh09xmm5oPTp5TiqR0okrDYDRjMLg2LJJDsP9aonxh805JR9yH+avX9rySnfr+7DWhKrrNI+d1ek+vXb2CSKLQV+kzr+9j5VK0ZCH0= 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: On Mon, Jun 2, 2025 at 9:11=E2=80=AFAM Jason Gunthorpe wro= te: > > On Sat, May 31, 2025 at 08:16:14PM -0700, David Rientjes wrote: > > Pratyush asked about the relationship between KHO and LUO. Pasha noted > > that KHO provides a state machine and in RFC v2 of LUO, LUO can drive K= HO > > which makes the KHO debugfs interface optional. KHO activate will caus= e > > LUO to switch to the prepared phase, for example. /dev/liveupdate > > continues to be the preferred mechanism. Think of KHO as preserving st= ate > > across kexec whereas LUO provides the state machine. > > IMHO LUO should superceed the statemachine in KHO and it's > debugfs. Just remove all the KHO stuff here. We don't need two things.. I agree, these two patches [1] [2] make KHO debugfs optional. I think it is reasonable to keep KHO debugfs interface optionally available for selftests, debugging, and development purposes. I do not think it will be needed in production. [1] https://lore.kernel.org/all/20250515182322.117840-2-pasha.tatashin@sole= en.com/ [2] https://lore.kernel.org/all/20250515182322.117840-3-pasha.tatashin@sole= en.com/ Pasha