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a=ed25519-sha256; t=1770934330; l=883; i=jannh@google.com; s=20240730; h=from:subject:message-id; bh=GF6lofjVwO8F2sO2S/yR98Ft0GCJ/p8OaGLlVtdB1pY=; b=g98iJ8I5OHvAqt+o8QHwhnFyhQ42KmzZmqXtWLF5UkUld7x1jW7oOGb0cmGrU1uPt8p+KNEnt Z61Pw/oNGnxB4RFWEfom/iYH1WiUirZu5oFt5/YYT8scpWAoVNXYNg/ X-Developer-Key: i=jannh@google.com; a=ed25519; pk=AljNtGOzXeF6khBXDJVVvwSEkVDGnnZZYqfWhP1V+C8= Task::pid() and Task::group_leader() wrongly assume that task::pid and task::group_leader remain constant until the task refcount drops to zero, but those members can actually change due to concurrent de_thread(). Fix those assumptions. Signed-off-by: Jann Horn --- Changes in v2: - split into two patches (Boqun) - use relaxed atomic load instead of volatile load (Boqun) - Link to v1: https://lore.kernel.org/r/20260212-rust-de_thread-v1-1-948f5b992624@google.com --- Jann Horn (2): rust: task: limit group_leader() to current rust: task: use atomic read for pid() rust/kernel/task.rs | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) --- base-commit: 192c0159402e6bfbe13de6f8379546943297783d change-id: 20260212-rust-de_thread-0ad9154aedb0 -- Jann Horn