/** * dwc3-of-simple.c - OF glue layer for simple integrations * * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com * * Author: Felipe Balbi * * 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. * * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov * and the original patch adding support for Xilinx' SoC * by Subbaraya Sundeep Bhatta */ #include #include #include #include #include #include #include #include #include #include struct dwc3_of_simple { struct device *dev; struct clk **clks; int num_clocks; }; static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count) { struct device *dev = simple->dev; struct device_node *np = dev->of_node; int i; simple->num_clocks = count; if (!count) return 0; simple->clks = devm_kcalloc(dev, simple->num_clocks, sizeof(struct clk *), GFP_KERNEL); if (!simple->clks) return -ENOMEM; for (i = 0; i < simple->num_clocks; i++) { struct clk *clk; int ret; clk = of_clk_get(np, i); if (IS_ERR(clk)) { while (--i >= 0) clk_put(simple->clks[i]); return PTR_ERR(clk); } ret = clk_prepare_enable(clk); if (ret < 0) { while (--i >= 0) { clk_disable_unprepare(simple->clks[i]); clk_put(simple->clks[i]); } clk_put(clk); return ret; } simple->clks[i] = clk; } return 0; } static int dwc3_of_simple_probe(struct platform_device *pdev) { struct dwc3_of_simple *simple; struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; int ret; int i; simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL); if (!simple) return -ENOMEM; platform_set_drvdata(pdev, simple); simple->dev = dev; ret = dwc3_of_simple_clk_init(simple, of_clk_get_parent_count(np)); if (ret) return ret; ret = of_platform_populate(np, NULL, NULL, dev); if (ret) { for (i = 0; i < simple->num_clocks; i++) { clk_disable_unprepare(simple->clks[i]); clk_put(simple->clks[i]); } return ret; } pm_runtime_set_active(dev); pm_runtime_enable(dev); pm_runtime_get_sync(dev); return 0; } static int dwc3_of_simple_remove(struct platform_device *pdev) { struct dwc3_of_simple *simple = platform_get_drvdata(pdev); struct device *dev = &pdev->dev; int i; for (i = 0; i < simple->num_clocks; i++) { clk_disable_unprepare(simple->clks[i]); clk_put(simple->clks[i]); } of_platform_depopulate(dev); pm_runtime_put_sync(dev); pm_runtime_disable(dev); return 0; } #ifdef CONFIG_PM static int dwc3_of_simple_runtime_suspend(struct device *dev) { struct dwc3_of_simple *simple = dev_get_drvdata(dev); int i; for (i = 0; i < simple->num_clocks; i++) clk_disable(simple->clks[i]); return 0; } static int dwc3_of_simple_runtime_resume(struct device *dev) { struct dwc3_of_simple *simple = dev_get_drvdata(dev); int ret; int i; for (i = 0; i < simple->num_clocks; i++) { ret = clk_enable(simple->clks[i]); if (ret < 0) { while (--i >= 0) clk_disable(simple->clks[i]); return ret; } } return 0; } #endif static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = { SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend, dwc3_of_simple_runtime_resume, NULL) }; static const struct of_device_id of_dwc3_simple_match[] = { { .compatible = "qcom,dwc3" }, { .compatible = "rockchip,rk3399-dwc3" }, { .compatible = "xlnx,zynqmp-dwc3" }, { .compatible = "cavium,octeon-7130-usb-uctl" }, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(of, of_dwc3_simple_match); static struct platform_driver dwc3_of_simple_driver = { .probe = dwc3_of_simple_probe, .remove = dwc3_of_simple_remove, .driver = { .name = "dwc3-of-simple", .of_match_table = of_dwc3_simple_match, }, }; module_platform_driver(dwc3_of_simple_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer"); MODULE_AUTHOR("Felipe Balbi "); Iago Abal <mail@iagoabal.eu>2017-01-11 14:00:21 +0100 committerVinod Koul <vinod.koul@intel.com>2017-01-25 15:35:11 +0530 commit91539eb1fda2d530d3b268eef542c5414e54bf1a (patch) tree960f5ca6342ad20837aff18aad6e8ecd7da32fd6 /net/core/sock_reuseport.c parent6610d0edf6dc7ee97e46ab3a538a565c79d26199 (diff)
dmaengine: pl330: fix double lock
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'net/core/sock_reuseport.c')