/* * Junction temperature thermal driver for Maxim Max77620. * * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. * * Author: Laxman Dewangan * Mallikarjun Kasoju * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #define MAX77620_NORMAL_OPERATING_TEMP 100000 #define MAX77620_TJALARM1_TEMP 120000 #define MAX77620_TJALARM2_TEMP 140000 struct max77620_therm_info { struct device *dev; struct regmap *rmap; struct thermal_zone_device *tz_device; int irq_tjalarm1; int irq_tjalarm2; }; /** * max77620_thermal_read_temp: Read PMIC die temperatue. * @data: Device specific data. * temp: Temperature in millidegrees Celsius * * The actual temperature of PMIC die is not available from PMIC. * PMIC only tells the status if it has crossed or not the threshold level * of 120degC or 140degC. * If threshold has not been crossed then assume die temperature as 100degC * else 120degC or 140deG based on the PMIC die temp threshold status. * * Return 0 on success otherwise error number to show reason of failure. */ static int max77620_thermal_read_temp(void *data, int *temp) { struct max77620_therm_info *mtherm = data; unsigned int val; int ret; ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val); if (ret < 0) { dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret); return ret; } if (val & MAX77620_IRQ_TJALRM2_MASK) *temp = MAX77620_TJALARM2_TEMP; else if (val & MAX77620_IRQ_TJALRM1_MASK) *temp = MAX77620_TJALARM1_TEMP; else *temp = MAX77620_NORMAL_OPERATING_TEMP; return 0; } static const struct thermal_zone_of_device_ops max77620_thermal_ops = { .get_temp = max77620_thermal_read_temp, }; static irqreturn_t max77620_thermal_irq(int irq, void *data) { struct max77620_therm_info *mtherm = data; if (irq == mtherm->irq_tjalarm1) dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n"); else if (irq == mtherm->irq_tjalarm2) dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n"); thermal_zone_device_update(mtherm->tz_device, THERMAL_EVENT_UNSPECIFIED); return IRQ_HANDLED; } static int max77620_thermal_probe(struct platform_device *pdev) { struct max77620_therm_info *mtherm; int ret; mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL); if (!mtherm) return -ENOMEM; mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0); mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1); if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) { dev_err(&pdev->dev, "Alarm irq number not available\n"); return -EINVAL; } pdev->dev.of_node = pdev->dev.parent->of_node; mtherm->dev = &pdev->dev; mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL); if (!mtherm->rmap) { dev_err(&pdev->dev, "Failed to get parent regmap\n"); return -ENODEV; } mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, mtherm, &max77620_thermal_ops); if (IS_ERR(mtherm->tz_device)) { ret = PTR_ERR(mtherm->tz_device); dev_err(&pdev->dev, "Failed to register thermal zone: %d\n", ret); return ret; } ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL, max77620_thermal_irq, IRQF_ONESHOT | IRQF_SHARED, dev_name(&pdev->dev), mtherm); if (ret < 0) { dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret); return ret; } ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL, max77620_thermal_irq, IRQF_ONESHOT | IRQF_SHARED, dev_name(&pdev->dev), mtherm); if (ret < 0) { dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret); return ret; } platform_set_drvdata(pdev, mtherm); return 0; } static struct platform_device_id max77620_thermal_devtype[] = { { .name = "max77620-thermal", }, {}, }; MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype); static struct platform_driver max77620_thermal_driver = { .driver = { .name = "max77620-thermal", }, .probe = max77620_thermal_probe, .id_table = max77620_thermal_devtype, }; module_platform_driver(max77620_thermal_driver); MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver"); MODULE_AUTHOR("Laxman Dewangan "); MODULE_AUTHOR("Mallikarjun Kasoju "); MODULE_LICENSE("GPL v2"); ef='/cgit.cgi/linux/net-next.git/commit/?id=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>2c5d9555d6d937966d79d4c6529a5f7b9206e405 (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>
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