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McKenney" , Metin Kaya , Xuewen Yan , K Prateek Nayak , Thomas Gleixner , Daniel Lezcano , Suleiman Souhlal , kuyo chang , hupu , kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Hey All, So in testing with the full Proxy Execution series, Vineeth Pillai managed to trip some interesting bugs which initially looked to be KVM or RCU related[1], which he later diagnosed as Proxy Execution related and created a useful test driver to reproduce. I found these same issues could be triggered with the upstream portions of Proxy Execution, so I wanted to send along these fixes for 7.1-rc Again, a huge thanks to Vineeth for uncovering these issues that have evaded all my stress testing so far! New in this version: * Peter didn't like the change modifying task __state in schedule() and so I've reworked this to use an extra bit flag in the low bit of the blocked_on pointer. This does make the change a little larger then I'd like for a fix, but I think minimizing it further would create a bit of a mess. Anyway, any feedback would be greatly appreciated! Thanks -john [1]: https://lore.kernel.org/lkml/20260320125633.2290675-1-vineeth@bitbyteword.org/ Cc: Vineeth Pillai Cc: Sonam Sanju Cc: Sean Christopherson Cc: Kunwu Chan Cc: Tejun Heo Cc: Joel Fernandes Cc: Qais Yousef Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot Cc: Dietmar Eggemann Cc: Valentin Schneider Cc: Steven Rostedt Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Cc: "Paul E. McKenney" Cc: Metin Kaya Cc: Xuewen Yan Cc: K Prateek Nayak Cc: Thomas Gleixner Cc: Daniel Lezcano Cc: Suleiman Souhlal Cc: kuyo chang Cc: hupu Cc: kernel-team@android.com John Stultz (2): sched: proxy-exec: Close race causing workqueue work being delayed locking: mutex: Fix proxy-exec potentially deactivating tasks marked TASK_RUNNING include/linux/sched.h | 64 ++++++++++++++++++++++++++++++++++-------- kernel/locking/mutex.c | 1 + kernel/sched/core.c | 15 ++++++---- 3 files changed, 64 insertions(+), 16 deletions(-) -- 2.54.0.545.g6539524ca2-goog