/* * Watchdog driver for Ricoh RN5T618 PMIC * * Copyright (C) 2014 Beniamino Galvani * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #define DRIVER_NAME "rn5t618-wdt" static bool nowayout = WATCHDOG_NOWAYOUT; static unsigned int timeout; module_param(timeout, uint, 0); MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds"); module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); struct rn5t618_wdt { struct watchdog_device wdt_dev; struct rn5t618 *rn5t618; }; /* * This array encodes the values of WDOGTIM field for the supported * watchdog expiration times. If the watchdog is not accessed before * the timer expiration, the PMU generates an interrupt and if the CPU * doesn't clear it within one second the system is restarted. */ static const struct { u8 reg_val; unsigned int time; } rn5t618_wdt_map[] = { { 0, 1 }, { 1, 8 }, { 2, 32 }, { 3, 128 }, }; static int rn5t618_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int t) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); int ret, i; for (i = 0; i < ARRAY_SIZE(rn5t618_wdt_map); i++) { if (rn5t618_wdt_map[i].time + 1 >= t) break; } if (i == ARRAY_SIZE(rn5t618_wdt_map)) return -EINVAL; ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGTIM_M, rn5t618_wdt_map[i].reg_val); if (!ret) wdt_dev->timeout = rn5t618_wdt_map[i].time; return ret; } static int rn5t618_wdt_start(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); int ret; ret = rn5t618_wdt_set_timeout(wdt_dev, wdt_dev->timeout); if (ret) return ret; /* enable repower-on */ ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_REPCNT, RN5T618_REPCNT_REPWRON, RN5T618_REPCNT_REPWRON); if (ret) return ret; /* enable watchdog */ ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGEN, RN5T618_WATCHDOG_WDOGEN); if (ret) return ret; /* enable watchdog interrupt */ return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIREN, RN5T618_PWRIRQ_IR_WDOG, RN5T618_PWRIRQ_IR_WDOG); } static int rn5t618_wdt_stop(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGEN, 0); } static int rn5t618_wdt_ping(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned int val; int ret; /* The counter is restarted after a R/W access to watchdog register */ ret = regmap_read(wdt->rn5t618->regmap, RN5T618_WATCHDOG, &val); if (ret) return ret; ret = regmap_write(wdt->rn5t618->regmap, RN5T618_WATCHDOG, val); if (ret) return ret; /* Clear pending watchdog interrupt */ return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIRQ, RN5T618_PWRIRQ_IR_WDOG, 0); } static struct watchdog_info rn5t618_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = DRIVER_NAME, }; static const struct watchdog_ops rn5t618_wdt_ops = { .owner = THIS_MODULE, .start = rn5t618_wdt_start, .stop = rn5t618_wdt_stop, .ping = rn5t618_wdt_ping, .set_timeout = rn5t618_wdt_set_timeout, }; static int rn5t618_wdt_probe(struct platform_device *pdev) { struct rn5t618 *rn5t618 = dev_get_drvdata(pdev->dev.parent); struct rn5t618_wdt *wdt; int min_timeout, max_timeout; wdt = devm_kzalloc(&pdev->dev, sizeof(struct rn5t618_wdt), GFP_KERNEL); if (!wdt) return -ENOMEM; min_timeout = rn5t618_wdt_map[0].time; max_timeout = rn5t618_wdt_map[ARRAY_SIZE(rn5t618_wdt_map) - 1].time; wdt->rn5t618 = rn5t618; wdt->wdt_dev.info = &rn5t618_wdt_info; wdt->wdt_dev.ops = &rn5t618_wdt_ops; wdt->wdt_dev.min_timeout = min_timeout; wdt->wdt_dev.max_timeout = max_timeout; wdt->wdt_dev.timeout = max_timeout; wdt->wdt_dev.parent = &pdev->dev; watchdog_set_drvdata(&wdt->wdt_dev, wdt); watchdog_init_timeout(&wdt->wdt_dev, timeout, &pdev->dev); watchdog_set_nowayout(&wdt->wdt_dev, nowayout); platform_set_drvdata(pdev, wdt); return watchdog_register_device(&wdt->wdt_dev); } static int rn5t618_wdt_remove(struct platform_device *pdev) { struct rn5t618_wdt *wdt = platform_get_drvdata(pdev); watchdog_unregister_device(&wdt->wdt_dev); return 0; } static struct platform_driver rn5t618_wdt_driver = { .probe = rn5t618_wdt_probe, .remove = rn5t618_wdt_remove, .driver = { .name = DRIVER_NAME, }, }; module_platform_driver(rn5t618_wdt_driver); MODULE_AUTHOR("Beniamino Galvani "); MODULE_DESCRIPTION("RN5T618 watchdog driver"); MODULE_LICENSE("GPL v2"); et-next.git/commit/include/dt-bindings/gpio?h=nds-private-remove&id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch) tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /include/dt-bindings/gpio 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 'include/dt-bindings/gpio')