/** * 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 "); mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch)
tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /tools/testing/selftests/efivarfs
parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/testing/selftests/efivarfs')