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2023-10-25regulator/core: Revert "fix kobject release warning and memory leak in ↵Michał Mirosław1-5/+1
regulator_register()" [ Upstream commit 6e800968f6a715c0661716d2ec5e1f56ed9f9c08 ] This reverts commit 5f4b204b6b8153923d5be8002c5f7082985d153f. Since rdev->dev now has a release() callback, the proper way of freeing the initialized device can be restored. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/d7f469f3f7b1f0e1d52f9a7ede3f3c5703382090.1695077303.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27regulator: core: Streamline debugfs operationsGeert Uytterhoeven1-17/+13
[ Upstream commit 08880713ceec023dd94d634f1e8902728c385939 ] If CONFIG_DEBUG_FS is not set: regulator: Failed to create debugfs directory ... regulator-dummy: Failed to create debugfs directory As per the comments for debugfs_create_dir(), errors returned by this function should be expected, and ignored: * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. * * NOTE: it's expected that most callers should _ignore_ the errors returned * by this function. Other debugfs functions handle the fact that the "dentry" * passed to them could be an error and they don't crash in that case. * Drivers should generally work fine even if debugfs fails to init anyway. Adhere to the debugfs spirit, and streamline all operations by: 1. Demoting the importance of the printed error messages to debug level, like is already done in create_regulator(), 2. Further ignoring any returned errors, as by design, all debugfs functions are no-ops when passed an error pointer. Fixes: 2bf1c45be3b8f3a3 ("regulator: Fix error checking for debugfs_create_dir") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/2f8bb6e113359ddfab7b59e4d4274bd4c06d6d0a.1685013051.git.geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27regulator: core: Fix more error checking for debugfs_create_dir()Geert Uytterhoeven1-1/+1
[ Upstream commit 2715bb11cfff964aa33946847f9527cfbd4874f5 ] In case of failure, debugfs_create_dir() does not return NULL, but an error pointer. Most incorrect error checks were fixed, but the one in create_regulator() was forgotten. Fix the remaining error check. Fixes: 2bf1c45be3b8f3a3 ("regulator: Fix error checking for debugfs_create_dir") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/ee980a108b5854dd8ce3630f8f673e784e057d17.1685013051.git.geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-21regulator: Fix error checking for debugfs_create_dirOsama Muhammad1-2/+2
[ Upstream commit 2bf1c45be3b8f3a3f898d0756c1282f09719debd ] This patch fixes the error checking in core.c in debugfs_create_dir. The correct way to check if an error occurred is 'IS_ERR' inline function. Signed-off-by: Osama Muhammad <osmtendev@gmail.com Suggested-by: Ivan Orlov <ivan.orlov0322@gmail.com Link: https://lore.kernel.org/r/20230515172938.13338-1-osmtendev@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17regulator: core: Avoid lockdep reports when resolving suppliesDouglas Anderson1-8/+83
[ Upstream commit cba6cfdc7c3f1516f0d08ddfb24e689af0932573 ] An automated bot told me that there was a potential lockdep problem with regulators. This was on the chromeos-5.15 kernel, but I see nothing that would be different downstream compared to upstream. The bot said: ============================================ WARNING: possible recursive locking detected 5.15.104-lockdep-17461-gc1e499ed6604 #1 Not tainted -------------------------------------------- kworker/u16:4/115 is trying to acquire lock: ffffff8083110170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: create_regulator+0x398/0x7ec but task is already holding lock: ffffff808378e170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: ww_mutex_trylock+0x3c/0x7b8 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(regulator_ww_class_mutex); lock(regulator_ww_class_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/u16:4/115: #0: ffffff808006a948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x520/0x1348 #1: ffffffc00e0a7cc0 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x55c/0x1348 #2: ffffff80828a2260 (&dev->mutex){....}-{3:3}, at: __device_attach_async_helper+0xd0/0x2a4 #3: ffffff808378e170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: ww_mutex_trylock+0x3c/0x7b8 stack backtrace: CPU: 2 PID: 115 Comm: kworker/u16:4 Not tainted 5.15.104-lockdep-17461-gc1e499ed6604 #1 9292e52fa83c0e23762b2b3aa1bacf5787a4d5da Hardware name: Google Quackingstick (rev0+) (DT) Workqueue: events_unbound async_run_entry_fn Call trace: dump_backtrace+0x0/0x4ec show_stack+0x34/0x50 dump_stack_lvl+0xdc/0x11c dump_stack+0x1c/0x48 __lock_acquire+0x16d4/0x6c74 lock_acquire+0x208/0x750 __mutex_lock_common+0x11c/0x11f8 ww_mutex_lock+0xc0/0x440 create_regulator+0x398/0x7ec regulator_resolve_supply+0x654/0x7c4 regulator_register_resolve_supply+0x30/0x120 class_for_each_device+0x1b8/0x230 regulator_register+0x17a4/0x1f40 devm_regulator_register+0x60/0xd0 reg_fixed_voltage_probe+0x728/0xaec platform_probe+0x150/0x1c8 really_probe+0x274/0xa20 __driver_probe_device+0x1dc/0x3f4 driver_probe_device+0x78/0x1c0 __device_attach_driver+0x1ac/0x2c8 bus_for_each_drv+0x11c/0x190 __device_attach_async_helper+0x1e4/0x2a4 async_run_entry_fn+0xa0/0x3ac process_one_work+0x638/0x1348 worker_thread+0x4a8/0x9c4 kthread+0x2e4/0x3a0 ret_from_fork+0x10/0x20 The problem was first reported soon after we made many of the regulators probe asynchronously, though nothing I've seen implies that the problems couldn't have also happened even without that. I haven't personally been able to reproduce the lockdep issue, but the issue does look somewhat legitimate. Specifically, it looks like in regulator_resolve_supply() we are holding a "rdev" lock while calling set_supply() -> create_regulator() which grabs the lock of a _different_ "rdev" (the one for our supply). This is not necessarily safe from a lockdep perspective since there is no documented ordering between these two locks. In reality, we should always be locking a regulator before the supplying regulator, so I don't expect there to be any real deadlocks in practice. However, the regulator framework in general doesn't express this to lockdep. Let's fix the issue by simply grabbing the two locks involved in the same way we grab multiple locks elsewhere in the regulator framework: using the "wound/wait" mechanisms. Fixes: eaa7995c529b ("regulator: core: avoid regulator_resolve_supply() race condition") Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230329143317.RFC.v2.2.I30d8e1ca10cfbe5403884cdd192253a2e063eb9e@changeid Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17regulator: core: Consistently set mutex_owner when using ww_mutex_lock_slow()Douglas Anderson1-0/+2
[ Upstream commit b83a1772be854f87602de14726737d3e5b06e1f4 ] When a codepath locks a rdev using ww_mutex_lock_slow() directly then that codepath is responsible for incrementing the "ref_cnt" and also setting the "mutex_owner" to "current". The regulator core consistently got that right for "ref_cnt" but didn't always get it right for "mutex_owner". Let's fix this. It's unlikely that this truly matters because the "mutex_owner" is only needed if we're going to do subsequent locking of the same rdev. However, even though it's not truly needed it seems less surprising if we consistently set "mutex_owner" properly. Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230329143317.RFC.v2.1.I4e9d433ea26360c06dd1381d091c82bb1a4ce843@changeid Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14regulator: core: fix deadlock on regulator enableJohan Hovold1-1/+1
commit cb3543cff90a4448ed560ac86c98033ad5fecda9 upstream. When updating the operating mode as part of regulator enable, the caller has already locked the regulator tree and drms_uA_update() must not try to do the same in order not to trigger a deadlock. The lock inversion is reported by lockdep as: ====================================================== WARNING: possible circular locking dependency detected 6.1.0-next-20221215 #142 Not tainted ------------------------------------------------------ udevd/154 is trying to acquire lock: ffffc11f123d7e50 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x280 but task is already holding lock: ffff80000e4c36e8 (regulator_ww_class_acquire){+.+.}-{0:0}, at: regulator_enable+0x34/0x80 which lock already depends on the new lock. ... Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(regulator_ww_class_acquire); lock(regulator_list_mutex); lock(regulator_ww_class_acquire); lock(regulator_list_mutex); *** DEADLOCK *** just before probe of a Qualcomm UFS controller (occasionally) deadlocks when enabling one of its regulators. Fixes: 9243a195be7a ("regulator: core: Change voltage setting path") Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") Cc: stable@vger.kernel.org # 5.0 Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20221215104646.19818-1-johan+linaro@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-14regulator: core: fix use_count leakage when handling boot-onRui Zhang1-1/+7
[ Upstream commit 0591b14ce0398125439c759f889647369aa616a0 ] I found a use_count leakage towards supply regulator of rdev with boot-on option. ┌───────────────────┐ ┌───────────────────┐ │ regulator_dev A │ │ regulator_dev B │ │ (boot-on) │ │ (boot-on) │ │ use_count=0 │◀──supply──│ use_count=1 │ │ │ │ │ └───────────────────┘ └───────────────────┘ In case of rdev(A) configured with `regulator-boot-on', the use_count of supplying regulator(B) will increment inside regulator_enable(rdev->supply). Thus, B will acts like always-on, and further balanced regulator_enable/disable cannot actually disable it anymore. However, B was also configured with `regulator-boot-on', we wish it could be disabled afterwards. Signed-off-by: Rui Zhang <zr.zhang@vivo.com> Link: https://lore.kernel.org/r/20221201033806.2567812-1-zr.zhang@vivo.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14regulator: core: fix resource leak in regulator_register()Yang Yingliang1-0/+1
[ Upstream commit ba62319a42c50e6254e98b3f316464fac8e77968 ] I got some resource leak reports while doing fault injection test: OF: ERROR: memory leak, expected refcount 1 instead of 100, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /i2c/pmic@64/regulators/buck1 unreferenced object 0xffff88810deea000 (size 512): comm "490-i2c-rt5190a", pid 253, jiffies 4294859840 (age 5061.046s) hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff a0 1e 00 a1 ff ff ff ff ................ backtrace: [<00000000d78541e2>] kmalloc_trace+0x21/0x110 [<00000000b343d153>] device_private_init+0x32/0xd0 [<00000000be1f0c70>] device_add+0xb2d/0x1030 [<00000000e3e6344d>] regulator_register+0xaf2/0x12a0 [<00000000e2f5e754>] devm_regulator_register+0x57/0xb0 [<000000008b898197>] rt5190a_probe+0x52a/0x861 [rt5190a_regulator] unreferenced object 0xffff88810b617b80 (size 32): comm "490-i2c-rt5190a", pid 253, jiffies 4294859904 (age 5060.983s) hex dump (first 32 bytes): 72 65 67 75 6c 61 74 6f 72 2e 32 38 36 38 2d 53 regulator.2868-S 55 50 50 4c 59 00 ff ff 29 00 00 00 2b 00 00 00 UPPLY...)...+... backtrace: [<000000009da9280d>] __kmalloc_node_track_caller+0x44/0x1b0 [<0000000025c6a4e5>] kstrdup+0x3a/0x70 [<00000000790efb69>] create_regulator+0xc0/0x4e0 [<0000000005ed203a>] regulator_resolve_supply+0x2d4/0x440 [<0000000045796214>] regulator_register+0x10b3/0x12a0 [<00000000e2f5e754>] devm_regulator_register+0x57/0xb0 [<000000008b898197>] rt5190a_probe+0x52a/0x861 [rt5190a_regulator] After calling regulator_resolve_supply(), the 'rdev->supply' is set by set_supply(), after this set, in the error path, the resources need be released, so call regulator_put() to avoid the leaks. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Fixes: 8a866d527ac0 ("regulator: core: Resolve supply name earlier to prevent double-init") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221202025111.496402-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14regulator: core: fix module refcount leak in set_supply()Yang Yingliang1-0/+1
[ Upstream commit da46ee19cbd8344d6860816b4827a7ce95764867 ] If create_regulator() fails in set_supply(), the module refcount needs be put to keep refcount balanced. Fixes: e2c09ae7a74d ("regulator: core: Increase refcount for regulator supply's module") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221201122706.4055992-2-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14regulator: core: use kfree_const() to free space conditionallyWang ShaoBo1-1/+1
[ Upstream commit dc8d006d15b623c1d80b90b45d6dcb6e890dad09 ] Use kfree_const() to free supply_name conditionally in create_regulator() as supply_name may be allocated from kmalloc() or directly from .rodata section. Fixes: 87fe29b61f95 ("regulator: push allocations in create_regulator() outside of lock") Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com> Link: https://lore.kernel.org/r/20221123034616.3609537-1-bobo.shaobowang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14regulator: core: fix unbalanced of node refcount in regulator_dev_lookup()Yang Yingliang1-0/+1
[ Upstream commit f2b41b748c19962b82709d9f23c6b2b0ce9d2f91 ] I got the the following report: OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /i2c/pmic@62/regulators/exten In of_get_regulator(), the node is returned from of_parse_phandle() with refcount incremented, after using it, of_node_put() need be called. Fixes: 69511a452e6d ("regulator: map consumer regulator based on device tree") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221115091508.900752-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02regulator: core: fix UAF in destroy_regulator()Yang Yingliang1-1/+1
[ Upstream commit 1f386d6894d0f1b7de8ef640c41622ddd698e7ab ] I got a UAF report as following: ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x935/0x2060 Read of size 8 at addr ffff88810e838220 by task python3/268 Call Trace: <TASK> dump_stack_lvl+0x67/0x83 print_report+0x178/0x4b0 kasan_report+0x90/0x190 __lock_acquire+0x935/0x2060 lock_acquire+0x156/0x400 _raw_spin_lock+0x2a/0x40 lockref_get+0x11/0x30 simple_recursive_removal+0x41/0x440 debugfs_remove.part.12+0x32/0x50 debugfs_remove+0x29/0x30 _regulator_put.cold.54+0x3e/0x27f regulator_put+0x1f/0x30 release_nodes+0x6a/0xa0 devres_release_all+0xf8/0x150 Allocated by task 37: kasan_save_stack+0x1c/0x40 kasan_set_track+0x21/0x30 __kasan_slab_alloc+0x5d/0x70 slab_post_alloc_hook+0x62/0x510 kmem_cache_alloc_lru+0x222/0x5a0 __d_alloc+0x31/0x440 d_alloc+0x30/0xf0 d_alloc_parallel+0xc4/0xd20 __lookup_slow+0x15e/0x2f0 lookup_one_len+0x13a/0x150 start_creating+0xea/0x190 debugfs_create_dir+0x1e/0x210 create_regulator+0x254/0x4e0 _regulator_get+0x2a1/0x467 _devm_regulator_get+0x5a/0xb0 regulator_virtual_probe+0xb9/0x1a0 Freed by task 30: kasan_save_stack+0x1c/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x50 __kasan_slab_free+0x102/0x190 kmem_cache_free+0xf6/0x600 rcu_core+0x54c/0x12b0 __do_softirq+0xf2/0x5e3 Last potentially related work creation: kasan_save_stack+0x1c/0x40 __kasan_record_aux_stack+0x98/0xb0 call_rcu+0x42/0x700 dentry_free+0x6c/0xd0 __dentry_kill+0x23b/0x2d0 dput.part.31+0x431/0x780 simple_recursive_removal+0xa9/0x440 debugfs_remove.part.12+0x32/0x50 debugfs_remove+0x29/0x30 regulator_unregister+0xe3/0x230 release_nodes+0x6a/0xa0 ================================================================== Here is how happened: processor A processor B regulator_register() rdev_init_debugfs() rdev->debugfs = debugfs_create_dir() devm_regulator_get() rdev = regulator_dev_lookup() create_regulator(rdev) // using rdev->debugfs as parent debugfs_create_dir(rdev->debugfs) mfd_remove_devices_fn() release_nodes() regulator_unregister() // free rdev->debugfs debugfs_remove_recursive(rdev->debugfs) release_nodes() destroy_regulator() debugfs_remove_recursive() <- causes UAF In devm_regulator_get(), after getting rdev, the refcount is get, so fix this by moving debugfs_remove_recursive() to regulator_dev_release(), then it can be proctected by the refcount, the 'rdev->debugfs' can not be freed until the refcount is 0. Fixes: 5de705194e98 ("regulator: Add basic per consumer debugfs") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221116033706.3595812-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02regulator: core: fix kobject release warning and memory leak in ↵Zeng Heng1-1/+5
regulator_register() [ Upstream commit 5f4b204b6b8153923d5be8002c5f7082985d153f ] Here is a warning report about lack of registered release() from kobject lib: Device '(null)' does not have a release() function, it is broken and must be fixed. WARNING: CPU: 0 PID: 48430 at drivers/base/core.c:2332 device_release+0x104/0x120 Call Trace: kobject_put+0xdc/0x180 put_device+0x1b/0x30 regulator_register+0x651/0x1170 devm_regulator_register+0x4f/0xb0 When regulator_register() returns fail and directly goto `clean` symbol, rdev->dev has not registered release() function yet (which is registered by regulator_class in the following), so rdev needs to be freed manually. If rdev->dev.of_node is not NULL, which means the of_node has gotten by regulator_of_get_init_data(), it needs to call of_node_put() to avoid refcount leak. Otherwise, only calling put_device() would lead memory leak of rdev in further: unreferenced object 0xffff88810d0b1000 (size 2048): comm "107-i2c-rtq6752", pid 48430, jiffies 4342258431 (age 1341.780s) backtrace: kmalloc_trace+0x22/0x110 regulator_register+0x184/0x1170 devm_regulator_register+0x4f/0xb0 When regulator_register() returns fail and goto `wash` symbol, rdev->dev has registered release() function, so directly call put_device() to cleanup everything. Fixes: d3c731564e09 ("regulator: plug of_node leak in regulator_register()'s error path") Signed-off-by: Zeng Heng <zengheng4@huawei.com> Link: https://lore.kernel.org/r/20221116074339.1024240-1-zengheng4@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26regulator: core: Prevent integer underflowPatrick Rudolph1-1/+1
[ Upstream commit 8d8e16592022c9650df8aedfe6552ed478d7135b ] By using a ratio of delay to poll_enabled_time that is not integer time_remaining underflows and does not exit the loop as expected. As delay could be derived from DT and poll_enabled_time is defined in the driver this can easily happen. Use a signed iterator to make sure that the loop exits once the remaining time is negative. Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Link: https://lore.kernel.org/r/20220909125954.577669-1-patrick.rudolph@9elements.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15regulator: core: Clean up on enable failureAndrew Halaney1-2/+7
[ Upstream commit c32f1ebfd26bece77141257864ed7b4720da1557 ] If regulator_enable() fails, enable_count is incremented still. A consumer, assuming no matching regulator_disable() is necessary on failure, will then get this error message upon regulator_put() since enable_count is non-zero: [ 1.277418] WARNING: CPU: 3 PID: 1 at drivers/regulator/core.c:2304 _regulator_put.part.0+0x168/0x170 The consumer could try to fix this in their driver by cleaning up on error from regulator_enable() (i.e. call regulator_disable()), but that results in the following since regulator_enable() failed and didn't increment user_count: [ 1.258112] unbalanced disables for vreg_l17c [ 1.262606] WARNING: CPU: 4 PID: 1 at drivers/regulator/core.c:2899 _regulator_disable+0xd4/0x190 Fix this by decrementing enable_count upon failure to enable. With this in place, just the reason for failure to enable is printed as expected and developers can focus on the root cause of their issue instead of thinking their usage of the regulator consumer api is incorrect. For example, in my case: [ 1.240426] vreg_l17c: invalid input voltage found Fixes: 5451781dadf8 ("regulator: core: Only count load for enabled consumers") Signed-off-by: Andrew Halaney <ahalaney@redhat.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Brian Masney <bmasney@redhat.com> Link: https://lore.kernel.org/r/20220819194336.382740-1-ahalaney@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09regulator: core: Fix enable_count imbalance with EXCLUSIVE_GETZev Weiss1-2/+5
[ Upstream commit c3e3ca05dae37f8f74bb80358efd540911cbc2c8 ] Since the introduction of regulator->enable_count, a driver that did an exclusive get on an already-enabled regulator would end up with enable_count initialized to 0 but rdev->use_count initialized to 1. With that starting point the regulator is effectively stuck enabled, because if the driver attempted to disable it it would fail the enable_count underflow check in _regulator_handle_consumer_disable(). The EXCLUSIVE_GET path in _regulator_get() now initializes enable_count along with rdev->use_count so that the regulator can be disabled without underflowing the former. Signed-off-by: Zev Weiss <zev@bewilderbeest.net> Fixes: 5451781dadf85 ("regulator: core: Only count load for enabled consumers") Link: https://lore.kernel.org/r/20220505043152.12933-1-zev@bewilderbeest.net Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-08regulator: core: fix false positive in regulator_late_cleanup()Oliver Barta1-10/+3
[ Upstream commit 4e2a354e3775870ca823f1fb29bbbffbe11059a6 ] The check done by regulator_late_cleanup() to detect whether a regulator is on was inconsistent with the check done by _regulator_is_enabled(). While _regulator_is_enabled() takes the enable GPIO into account, regulator_late_cleanup() was not doing that. This resulted in a false positive, e.g. when a GPIO-controlled fixed regulator was used, which was not enabled at boot time, e.g. reg_disp_1v2: reg_disp_1v2 { compatible = "regulator-fixed"; regulator-name = "display_1v2"; regulator-min-microvolt = <1200000>; regulator-max-microvolt = <1200000>; gpio = <&tlmm 148 0>; enable-active-high; }; Such regulator doesn't have an is_enabled() operation. Nevertheless it's state can be determined based on the enable GPIO. The check in regulator_late_cleanup() wrongly assumed that the regulator is on and tried to disable it. Signed-off-by: Oliver Barta <oliver.barta@aptiv.com> Link: https://lore.kernel.org/r/20220208084645.8686-1-oliver.barta@aptiv.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-16regulator: core: resolve supply for boot-on/always-on regulatorsDmitry Baryshkov1-0/+6
commit 98e48cd9283dbac0e1445ee780889f10b3d1db6a upstream. For the boot-on/always-on regulators the set_machine_constrainst() is called before resolving rdev->supply. Thus the code would try to enable rdev before enabling supplying regulator. Enforce resolving supply regulator before enabling rdev. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Link: https://lore.kernel.org/r/20210519221224.2868496-1-dmitry.baryshkov@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04regulator: core: Avoid debugfs: Directory ... already present! errorHans de Goede1-3/+3
[ Upstream commit dbe954d8f1635f949a1d9a5d6e6fb749ae022b47 ] Sometimes regulator_get() gets called twice for the same supply on the same device. This may happen e.g. when a framework / library is used which uses the regulator; and the driver itself also needs to enable the regulator in some cases where the framework will not enable it. Commit ff268b56ce8c ("regulator: core: Don't spew backtraces on duplicate sysfs") already takes care of the backtrace which would trigger when creating a duplicate consumer symlink under /sys/class/regulator/regulator.%d in this scenario. Commit c33d442328f5 ("debugfs: make error message a bit more verbose") causes a new error to get logged in this scenario: [ 26.938425] debugfs: Directory 'wm5102-codec-MICVDD' with parent 'spi-WM510204:00-MICVDD' already present! There is no _nowarn variant of debugfs_create_dir(), but we can detect and avoid this problem by checking the return value of the earlier sysfs_create_link_nowarn() call. Add a check for the earlier sysfs_create_link_nowarn() failing with -EEXIST and skip the debugfs_create_dir() call in that case, avoiding this error getting logged. Fixes: c33d442328f5 ("debugfs: make error message a bit more verbose") Cc: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20210122183250.370571-1-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13regulator: Fix lockdep warning resolving suppliesMark Brown1-12/+17
[ Upstream commit 14a71d509ac809dcf56d7e3ca376b15d17bd0ddd ] With commit eaa7995c529b54 (regulator: core: avoid regulator_resolve_supply() race condition) we started holding the rdev lock while resolving supplies, an operation that requires holding the regulator_list_mutex. This results in lockdep warnings since in other places we take the list mutex then the mutex on an individual rdev. Since the goal is to make sure that we don't call set_supply() twice rather than a concern about the cost of resolution pull the rdev lock and check for duplicate resolution down to immediately before we do the set_supply() and drop it again once the allocation is done. Fixes: eaa7995c529b54 (regulator: core: avoid regulator_resolve_supply() race condition) Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20210122132042.10306-1-broonie@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13regulator: core: avoid regulator_resolve_supply() race conditionDavid Collins1-11/+28
[ Upstream commit eaa7995c529b54d68d97a30f6344cc6ca2f214a7 ] The final step in regulator_register() is to call regulator_resolve_supply() for each registered regulator (including the one in the process of being registered). The regulator_resolve_supply() function first checks if rdev->supply is NULL, then it performs various steps to try to find the supply. If successful, rdev->supply is set inside of set_supply(). This procedure can encounter a race condition if two concurrent tasks call regulator_register() near to each other on separate CPUs and one of the regulators has rdev->supply_name specified. There is currently nothing guaranteeing atomicity between the rdev->supply check and set steps. Thus, both tasks can observe rdev->supply==NULL in their regulator_resolve_supply() calls. This then results in both creating a struct regulator for the supply. One ends up actually stored in rdev->supply and the other is lost (though still present in the supply's consumer_list). Here is a kernel log snippet showing the issue: [ 12.421768] gpu_cc_gx_gdsc: supplied by pm8350_s5_level [ 12.425854] gpu_cc_gx_gdsc: supplied by pm8350_s5_level [ 12.429064] debugfs: Directory 'regulator.4-SUPPLY' with parent '17a00000.rsc:rpmh-regulator-gfxlvl-pm8350_s5_level' already present! Avoid this race condition by holding the rdev->mutex lock inside of regulator_resolve_supply() while checking and setting rdev->supply. Signed-off-by: David Collins <collinsd@codeaurora.org> Link: https://lore.kernel.org/r/1610068562-4410-1-git-send-email-collinsd@codeaurora.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-13regulator: workaround self-referent regulatorsMichał Mirosław1-1/+4
Workaround regulators whose supply name happens to be the same as its own name. This fixes boards that used to work before the early supply resolving was removed. The error message is left in place so that offending drivers can be detected. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Cc: stable@vger.kernel.org Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1 Link: https://lore.kernel.org/r/d703acde2a93100c3c7a81059d716c50ad1b1f52.1605226675.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-13regulator: avoid resolve_supply() infinite recursionMichał Mirosław1-0/+6
When a regulator's name equals its supply's name the regulator_resolve_supply() recurses indefinitely. Add a check so that debugging the problem is easier. The "fixed" commit just exposed the problem. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Cc: stable@vger.kernel.org Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1 Link: https://lore.kernel.org/r/c6171057cfc0896f950c4d8cb82df0f9f1b89ad9.1605226675.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-13regulator: fix memory leak with repeated set_machine_constraints()Michał Mirosław1-16/+13
Fixed commit introduced a possible second call to set_machine_constraints() and that allocates memory for rdev->constraints. Move the allocation to the caller so it's easier to manage and done once. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Cc: stable@vger.kernel.org Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # stpmic1 Link: https://lore.kernel.org/r/78c3d4016cebc08d441aad18cb924b4e4d9cf9df.1605226675.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-10regulator: core: don't disable regulator if is_enabled return error.Pi-Hsun Shih1-2/+3
In regulator_late_cleanup when is_enabled failed, don't try to disable the regulator since it would likely to fail too and causing confusing error messages. Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org> Link: https://lore.kernel.org/r/20201106064817.3290927-1-pihsun@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-03regulator: defer probe when trying to get voltage from unresolved supplyMichał Mirosław1-0/+2
regulator_get_voltage_rdev() is called in regulator probe() when applying machine constraints. The "fixed" commit exposed the problem that non-bypassed regulators can forward the request to its parent (like bypassed ones) supply. Return -EPROBE_DEFER when the supply is expected but not resolved yet. Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator") Cc: stable@vger.kernel.org Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reported-by: Ondřej Jirman <megous@megous.com> Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com> Tested-by: Ondřej Jirman <megous@megous.com> Link: https://lore.kernel.org/r/a9041d68b4d35e4a2dd71629c8a6422662acb5ee.1604351936.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-10-05Merge remote-tracking branch 'regulator/for-5.10' into regulator-nextMark Brown1-96/+143
2020-10-05regulator: Make constraint debug processing conditional on DEBUGGeert Uytterhoeven1-1/+12
If debugging is disabled, print_constraints() does not print the actual constraints, but still performs some processing and string formatting, only to throw away the result later. Fix this by moving all constraint debug processing to a separate function, and replacing it by a dummy when debugging is disabled. This reduces kernel size by almost 800 bytes (on arm/arm64). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20201005131546.22448-1-geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org>
2020-10-01regulator: core: Enlarge max OF property name length to 64 charsAngeloGioacchino Del Regno1-2/+2
Some regulator drivers may be defining very long names: this is the case with the qcom_smd and qcom_spmi regulators, where we need to parse the regulator parents from DT. For clarity, this is an example: { "l13a", QCOM_SMD_RPM_LDOA, 13, &pm660_ht_lvpldo, "vdd_l8_l9_l10_l11_l12_l13_l14" }, pm660-regulators { ... vdd_l8_l9_l10_l11_l12_l13_l14-supply = <&vreg_s4a_2p04> ... }; Now, with a 32 characters limit, the function is trying to parse, exactly, "vdd_l8_l9_l10_l11_l12_l13_l14-s" (32 chars) instead of the right one, which is 37 chars long in this specific case. ... And this is not only the case with PM660/PM660L, but also with PMA8084, PM8916, PM8950 and others that are not implemented yet. The length of 64 chars was chosen based on the longest parsed property name that I could find, which is in PM8916, and would be 53 characters long. At that point, rounding that to 64 looked like being the best idea. Signed-off-by: AngeloGioacchino Del Regno <kholk11@gmail.com> Link: https://lore.kernel.org/r/20200926125549.13191-2-kholk11@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-28regulator: resolve supply after creating regulatorMichał Mirosław1-8/+13
When creating a new regulator its supply cannot create the sysfs link because the device is not yet published. Remove early supply resolving since it will be done later anyway. This makes the following error disappear and the symlinks get created instead. DCDC_REG1: supplied by VSYS VSYS: could not add device link regulator.3 err -2 Note: It doesn't fix the problem for bypassed regulators, though. Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/ba09e0a8617ffeeb25cb4affffe6f3149319cef8.1601155770.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-28regulator: print symbolic errors in kernel messagesMichał Mirosław1-45/+49
Change all error-printing messages to include error name via %pe instead of numeric error or nothing. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/1dcf25f39188882eb56918a9aa281ab17b792aa5.1601155770.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-28regulator: print state at bootMichał Mirosław1-2/+7
Make the initial state of the regulator shown when debugging. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/53c4f3d394d68f0989174f89e3b0882cebbbd787.1601155770.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-22regulator: fix indentation issueColin Ian King1-1/+1
There is a return statement that is indented with an extra space, fix this by removing it. Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20200920142454.33352-1-colin.king@canonical.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-21regulator: unexport regulator_lock/unlock()Michał Mirosław1-4/+2
regulator_lock/unlock() was used only to guard regulator_notifier_call_chain(). As no users remain, make the functions internal. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/d3381aabd2632aff5e7b839d55868bec6e85c811.1600550732.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-17Merge series "Support ROHM BD9576MUF and BD9573MUF PMICs" from Matti ↵Mark Brown1-1/+1
Vaittinen <matti.vaittinen@fi.rohmeurope.com>: Initial support for ROHM BD9576MUF and BD9573MUF PMICs. These PMICs are primarily intended to be used to power the R-Car family processors. BD9576MUF includes some additional safety features the BD9573MUF does not have. This initial version of drivers does not utilize these features and for now the SW behaviour is identical. Please note that this version of drivers is only tested on BD9576MUF but according to the data-sheets the relevant parts of registers should be same so drivers should also work on BD9573MUF. This patch series includes MFD, watchdog and regulator drivers with basic functionality such as: - Enabling and pinging the watchdog - configuring watchog timeout / window from device-tree - reading regulator states/voltages - enabling/disabling VOUT1 (VD50) when control mode B is used. This patch series does not bring interrupt support. BD9576MUF and BD9573MUF are designed to keep the IRQ line low for whole duration of error condition. IRQ can't be 'acked'. So proper IRQ support would require some IRQ limiter implementation (delayed unmask?) in order to not hog the CPU. --- Matti Vaittinen (6): dt_bindings: mfd: Add ROHM BD9576MUF and BD9573MUF PMICs dt_bindings: regulator: Add ROHM BD9576MUF and BD9573MUF PMICs mfd: Support ROHM BD9576MUF and BD9573MUF wdt: Support wdt on ROHM BD9576MUF and BD9573MUF regulator: Support ROHM BD9576MUF and BD9573MUF MAINTAINERS: Add ROHM BD9576MUF and BD9573MUF drivers .../bindings/mfd/rohm,bd9576-pmic.yaml | 129 +++++++ .../regulator/rohm,bd9576-regulator.yaml | 33 ++ MAINTAINERS | 4 + drivers/mfd/Kconfig | 11 + drivers/mfd/Makefile | 1 + drivers/mfd/rohm-bd9576.c | 130 +++++++ drivers/regulator/Kconfig | 10 + drivers/regulator/Makefile | 1 + drivers/regulator/bd9576-regulator.c | 337 ++++++++++++++++++ drivers/watchdog/Kconfig | 13 + drivers/watchdog/Makefile | 1 + drivers/watchdog/bd9576_wdt.c | 295 +++++++++++++++ include/linux/mfd/rohm-bd957x.h | 61 ++++ include/linux/mfd/rohm-generic.h | 2 + 14 files changed, 1028 insertions(+) create mode 100644 Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml create mode 100644 Documentation/devicetree/bindings/regulator/rohm,bd9576-regulator.yaml create mode 100644 drivers/mfd/rohm-bd9576.c create mode 100644 drivers/regulator/bd9576-regulator.c create mode 100644 drivers/watchdog/bd9576_wdt.c create mode 100644 include/linux/mfd/rohm-bd957x.h base-commit: f4d51dffc6c01a9e94650d95ce0104964f8ae822 -- 2.21.0 -- Matti Vaittinen, Linux device drivers ROHM Semiconductors, Finland SWDC Kiviharjunlenkki 1E 90220 OULU FINLAND ~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~ Simon says - in Latin please. ~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~ Thanks to Simon Glass for the translation =]
2020-09-11Merge tag 'regulator-fix-v5.9-rc4' of ↵Linus Torvalds1-83/+96
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator fixes from Mark Brown: "The biggest set of fixes here is those from Michał Mirosław fixing some locking issues with coupled regulators that are triggered in cases where a coupled regulator is used by a device involved in fs_reclaim like eMMC storage. These are relatively serious for the affected systems, though the circumstances where they trigger are very rare" * tag 'regulator-fix-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: pwm: Fix machine constraints application regulator: core: Fix slab-out-of-bounds in regulator_unlock_recursive() regulator: remove superfluous lock in regulator_resolve_coupling() regulator: cleanup regulator_ena_gpio_free() regulator: plug of_node leak in regulator_register()'s error path regulator: push allocation in set_consumer_device_supply() out of lock regulator: push allocations in create_regulator() outside of lock regulator: push allocation in regulator_ena_gpio_request() out of lock regulator: push allocation in regulator_init_coupling() outside of lock regulator: fix spelling mistake "Cant" -> "Can't" regulator: cros-ec-regulator: Add NULL test for devm_kmemdup call
2020-09-07regulator: don't require mutex for regulator_notifier_call_chain()Michał Mirosław1-4/+1
Since 3801b86aa482 ("regulator: Refactor supply implementation to work as regular consumers") we no longer cascade notifications and so notifier head's built-in rwsem is enough to protect the notifier chain. Remove the requirement to fix one case where rdev->mutex might be forced to be taken recursively. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/5a0da9017c69a4dbc3f9b50f44476fce80a73387.1597032945.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-01regulator: core: Fix slab-out-of-bounds in regulator_unlock_recursive()Dmitry Osipenko1-6/+9
The recent commit 7d8196641ee1 ("regulator: Remove pointer table overallocation") changed the size of coupled_rdevs and now KASAN is able to detect slab-out-of-bounds problem in regulator_unlock_recursive(), which is a legit problem caused by a typo in the code. The recursive unlock function uses n_coupled value of a parent regulator for unlocking supply regulator, while supply's n_coupled should be used. In practice problem may only affect platforms that use coupled regulators. Cc: stable@vger.kernel.org # 5.0+ Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/20200831204335.19489-1-digetx@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-1/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-18Merge series "regulator: fix deadlock vs memory reclaim" from Michał ↵Mark Brown1-73/+87
Mirosław <mirq-linux@rere.qmqm.pl>: For systems that have eg. eMMC storage using voltage regulator, memory reclaim path might call back into regulator subsystem. This means we have to make sure no allocations happen with a regulator or regulator list locked. After this series I see no more lockdep complaints on my test system, but please review and test further. First four patches move allocations out of locked regions, next three came as a drive-by cleanups. --- v2: fix bug in patch #4 spotted by kernel test robot reworded commit #7 description Michał Mirosław (7): regulator: push allocation in regulator_init_coupling() outside of lock regulator: push allocation in regulator_ena_gpio_request() out of lock regulator: push allocations in create_regulator() outside of lock regulator: push allocation in set_consumer_device_supply() out of lock regulator: plug of_node leak in regulator_register()'s error path regulator: cleanup regulator_ena_gpio_free() regulator: remove superfluous lock in regulator_resolve_coupling() drivers/regulator/core.c | 164 +++++++++++++++++++++------------------ 1 file changed, 87 insertions(+), 77 deletions(-) -- 2.20.1
2020-08-18regulator: Remove pointer table overallocationMichał Mirosław1-5/+5
The code allocates sizeof(regulator_dev) for a pointer. Make it less generous. Let kcalloc() calculate the size, while at it. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/407fbd06a02caf038a9ba3baa51c7d6d47cd6517.1597000795.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-18regulator: Avoid grabbing regulator lock during suspend/resumeStephen Boyd1-24/+51
I see it takes about 5us per regulator to grab the lock, check that this regulator isn't going to do anything for suspend, and then release the lock. When that is combined with PMICs that have dozens of regulators we get into a state where we spend a few miliseconds doing a bunch of locking operations synchronously to figure out that there's nothing to do. Let's reorganize the code here a bit so that we don't grab the lock until we're actually going to do something so that suspend is a little faster. Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200804070837.1084024-1-swboyd@chromium.org Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: remove superfluous lock in regulator_resolve_coupling()Michał Mirosław1-4/+0
The code modifies rdev, but locks c_rdev instead. Remove the lock as this is held together by regulator_list_mutex taken in the caller. Fixes: f9503385b187 ("regulator: core: Mutually resolve regulators coupling") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/25eb81cefb37a646f3e44eaaf1d8ae8881cfde52.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: cleanup regulator_ena_gpio_free()Michał Mirosław1-12/+12
Since only regulator_ena_gpio_request() allocates rdev->ena_pin, and it guarantees that same gpiod gets same pin structure, it is enough to compare just the pointers. Also we know there can be only one matching entry on the list. Rework the code take advantage of the facts. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/3ff002c7aa3bd774491af4291a9df23541fcf892.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: plug of_node leak in regulator_register()'s error pathMichał Mirosław1-9/+4
By calling device_initialize() earlier and noting that kfree(NULL) is ok, we can save a bit of code in error handling and plug of_node leak. Fixed commit already did part of the work. Fixes: 9177514ce349 ("regulator: fix memory leak on error path of regulator_register()") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Acked-by: Vladimir Zapolskiy <vz@mleia.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/f5035b1b4d40745e66bacd571bbbb5e4644d21a1.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: push allocation in set_consumer_device_supply() out of lockMichał Mirosław1-20/+26
Pull regulator_list_mutex into set_consumer_device_supply() and keep allocations outside of it. Fourth of the fs_reclaim deadlock case. Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/f0380bdb3d60aeefa9693c4e234d2dcda7e56747.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: push allocations in create_regulator() outside of lockMichał Mirosław1-25/+28
Move all allocations outside of the regulator_lock()ed section. ====================================================== WARNING: possible circular locking dependency detected 5.7.13+ #535 Not tainted ------------------------------------------------------ f2fs_discard-179:7/702 is trying to acquire lock: c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0 but task is already holding lock: cb95b080 (&dcc->cmd_lock){+.+.}-{3:3}, at: __issue_discard_cmd+0xec/0x5f8 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: [...] -> #3 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire.part.11+0x40/0x50 fs_reclaim_acquire+0x24/0x28 __kmalloc_track_caller+0x54/0x218 kstrdup+0x40/0x5c create_regulator+0xf4/0x368 regulator_resolve_supply+0x1a0/0x200 regulator_register+0x9c8/0x163c [...] other info that might help us debug this: Chain exists of: regulator_list_mutex --> &sit_i->sentry_lock --> &dcc->cmd_lock [...] Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/6eebc99b2474f4ffaa0405b15178ece0e7e4f608.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: push allocation in regulator_ena_gpio_request() out of lockMichał Mirosław1-5/+14
Move another allocation out of regulator_list_mutex-protected region, as reclaim might want to take the same lock. WARNING: possible circular locking dependency detected 5.7.13+ #534 Not tainted ------------------------------------------------------ kswapd0/383 is trying to acquire lock: c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0 but task is already holding lock: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire.part.11+0x40/0x50 fs_reclaim_acquire+0x24/0x28 kmem_cache_alloc_trace+0x40/0x1e8 regulator_register+0x384/0x1630 devm_regulator_register+0x50/0x84 reg_fixed_voltage_probe+0x248/0x35c [...] other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(regulator_list_mutex); lock(fs_reclaim); lock(regulator_list_mutex); *** DEADLOCK *** [...] 2 locks held by kswapd0/383: #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 #1: cb70e5e0 (hctx->srcu){....}-{0:0}, at: hctx_lock+0x60/0xb8 [...] Fixes: 541d052d7215 ("regulator: core: Only support passing enable GPIO descriptors") [this commit only changes context] Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") [this is when the regulator_list_mutex was introduced in reclaim locking path] Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Link: https://lore.kernel.org/r/41fe6a9670335721b48e8f5195038c3d67a3bf92.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
2020-08-17regulator: push allocation in regulator_init_coupling() outside of lockMichał Mirosław1-2/+3
Allocating memory with regulator_list_mutex held makes lockdep unhappy when memory pressure makes the system do fs_reclaim on eg. eMMC using a regulator. Push the lock inside regulator_init_coupling() after the allocation. ====================================================== WARNING: possible circular locking dependency detected 5.7.13+ #533 Not tainted ------------------------------------------------------ kswapd0/383 is trying to acquire lock: cca78ca4 (&sbi->write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154 but task is already holding lock: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire.part.11+0x40/0x50 fs_reclaim_acquire+0x24/0x28 __kmalloc+0x54/0x218 regulator_register+0x860/0x1584 dummy_regulator_probe+0x60/0xa8 [...] other info that might help us debug this: Chain exists of: &sbi->write_io[i][j].io_rwsem --> regulator_list_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(regulator_list_mutex); lock(fs_reclaim); lock(&sbi->write_io[i][j].io_rwsem); *** DEADLOCK *** 1 lock held by kswapd0/383: #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 [...] Fixes: d8ca7d184b33 ("regulator: core: Introduce API for regulators coupling customization") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
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