add lvds1024*800

hc

2024-01-31 f70575805708cabdedea7498aaa3f710fde4d920

 kernel/kernel/pid_namespace.c
..
..
@@ -251,7 +251,24 @@
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 		set_current_state(TASK_INTERRUPTIBLE);
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 		if (pid_ns->pid_allocated == init_pids)
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 			break;
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+		/*
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+		 * Release tasks_rcu_exit_srcu to avoid following deadlock:
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+		 *
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+		 * 1) TASK A unshare(CLONE_NEWPID)
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+		 * 2) TASK A fork() twice -> TASK B (child reaper for new ns)
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+		 *    and TASK C
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+		 * 3) TASK B exits, kills TASK C, waits for TASK A to reap it
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+		 * 4) TASK A calls synchronize_rcu_tasks()
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+		 *                   -> synchronize_srcu(tasks_rcu_exit_srcu)
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+		 * 5) *DEADLOCK*
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+		 *
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+		 * It is considered safe to release tasks_rcu_exit_srcu here
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+		 * because we assume the current task can not be concurrently
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+		 * reaped at this point.
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+		 */
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+		exit_tasks_rcu_stop();
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 		schedule();
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+		exit_tasks_rcu_start();
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 	}
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 	__set_current_state(TASK_RUNNING);
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