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Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?iso-8859-1?Q?Wei=DFschuh?= , Juri Lelli , Marcelo Tosatti , Yair Podemsky , Daniel Wagner , Petr Tesarik Subject: Re: [RFC PATCH v3 08/15] sched/clock, x86: Make __sched_clock_stable forceful Message-ID: <20241120145904.GK19989@noisy.programming.kicks-ass.net> References: <20241119153502.41361-1-vschneid@redhat.com> <20241119153502.41361-9-vschneid@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241119153502.41361-9-vschneid@redhat.com> X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 35B0114000E X-Stat-Signature: 6t5xtzdoh6xuzqc8a8bu37j5gi16dn98 X-Rspam-User: X-HE-Tag: 1732114720-356417 X-HE-Meta: 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 7soeZcOv PmeBQ5sP4dNJMqyTXvjcv0Tvp1VVcwmWgnxzq2aOzzJWk/E0ms2+mubML1+yzc0shcUxbxyGTbE5sucg5p53rpFuwpcXLAGIuntPL8C4u9GQgfJr2pc2uyHh/kcs/CZtXafigmkgnCE+Fzsq6btddkl9i7AGVofaoNmeOKmtRGJDfORiNH01fXGYoWg5Jk3jbPhdpvC+JHdnJK6LAiiY87heYLII44RChFsHtU8os09jPKCHTwV+BjMO3O5VhcLmZrn5L0X6cfLIIN75feVmDVJVMzxfxQMtWz4EtY2juek0+nHCMyY5oiVpTDQ== 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 Tue, Nov 19, 2024 at 04:34:55PM +0100, Valentin Schneider wrote: > Later commits will cause objtool to warn about non __ro_after_init static > keys being used in .noinstr sections in order to safely defer instruction > patching IPIs targeted at NOHZ_FULL CPUs. > > __sched_clock_stable is used in .noinstr code, and can be modified at > runtime (e.g. KVM module loading). Suppressing the text_poke_sync() IPI has Wait, what !? loading KVM causes the TSC to be marked unstable?