/* * of.c The helpers for hcd device tree support * * Copyright (C) 2016 Freescale Semiconductor, Inc. * Author: Peter Chen * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 of * the License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include /** * usb_of_get_child_node - Find the device node match port number * @parent: the parent device node * @portnum: the port number which device is connecting * * Find the node from device tree according to its port number. * * Return: On success, a pointer to the device node, %NULL on failure. */ struct device_node *usb_of_get_child_node(struct device_node *parent, int portnum) { struct device_node *node; u32 port; for_each_child_of_node(parent, node) { if (!of_property_read_u32(node, "reg", &port)) { if (port == portnum) return node; } } return NULL; } EXPORT_SYMBOL_GPL(usb_of_get_child_node); t plumbingsTobias Klauser
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authorAndrei Vagin <avagin@openvz.org>2017-01-04 19:28:14 -0800
committerEric W. Biederman <ebiederm@xmission.com>2017-01-10 13:34:56 +1300
commitadd7c65ca426b7a37184dd3d2172394e23d585d6 (patch)
tree28b08b519540041b06ed0ab0b1c005076b932e8e /tools/build/tests
parent75422726b0f717d67db3283c2eb5bc14fa2619c5 (diff)
pid: fix lockdep deadlock warning due to ucount_lock
========================================================= [ INFO: possible irq lock inversion dependency detected ] 4.10.0-rc2-00024-g4aecec9-dirty #118 Tainted: G W --------------------------------------------------------- swapper/1/0 just changed the state of lock: (&(&sighand->siglock)->rlock){-.....}, at: [<ffffffffbd0a1bc6>] __lock_task_sighand+0xb6/0x2c0 but this lock took another, HARDIRQ-unsafe lock in the past: (ucounts_lock){+.+...} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &(&sighand->siglock)->rlock --> &(&tty->ctrl_lock)->rlock --> ucounts_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(ucounts_lock); local_irq_disable(); lock(&(&sighand->siglock)->rlock); lock(&(&tty->ctrl_lock)->rlock); <Interrupt> lock(&(&sighand->siglock)->rlock); *** DEADLOCK *** This patch removes a dependency between rlock and ucount_lock. Fixes: f333c700c610 ("pidns: Add a limit on the number of pid namespaces") Cc: stable@vger.kernel.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'tools/build/tests')