From 3fb3cb4350befc4f901c54e0cb4a2a47b1302e08 Mon Sep 17 00:00:00 2001 From: Andrey Vatoropin Date: Thu, 30 Jan 2025 09:00:34 +0000 Subject: [PATCH 1/3] power: supply: da9150-fg: fix potential overflow Size of variable sd_gain equals four bytes - DA9150_QIF_SD_GAIN_SIZE. Size of variable shunt_val equals two bytes - DA9150_QIF_SHUNT_VAL_SIZE. The expression sd_gain * shunt_val is currently being evaluated using 32-bit arithmetic. So during the multiplication an overflow may occur. As the value of type 'u64' is used as storage for the eventual result, put ULL variable at the first position of each expression in order to give the compiler complete information about the proper arithmetic to use. According to C99 the guaranteed width for a variable of type 'unsigned long long' >= 64 bits. Remove the explicit cast to u64 as it is meaningless. Just for the sake of consistency, perform the similar trick with another expression concerning 'iavg'. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: a419b4fd9138 ("power: Add support for DA9150 Fuel-Gauge") Signed-off-by: Andrey Vatoropin Link: https://lore.kernel.org/r/20250130090030.53422-1-a.vatoropin@crpt.ru Signed-off-by: Sebastian Reichel --- drivers/power/supply/da9150-fg.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/power/supply/da9150-fg.c b/drivers/power/supply/da9150-fg.c index 652c1f213af1..4f28ef1bba1a 100644 --- a/drivers/power/supply/da9150-fg.c +++ b/drivers/power/supply/da9150-fg.c @@ -247,9 +247,9 @@ static int da9150_fg_current_avg(struct da9150_fg *fg, DA9150_QIF_SD_GAIN_SIZE); da9150_fg_read_sync_end(fg); - div = (u64) (sd_gain * shunt_val * 65536ULL); + div = 65536ULL * sd_gain * shunt_val; do_div(div, 1000000); - res = (u64) (iavg * 1000000ULL); + res = 1000000ULL * iavg; do_div(res, div); val->intval = (int) res; From 64dd6edfc421479e416301c48b79cece8d0351fc Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Thu, 30 Jan 2025 15:00:35 +0100 Subject: [PATCH 2/3] power: supply: core: Fix extension related lockdep warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit 6037802bbae8 ("power: supply: core: implement extension API") there is the following ABBA deadlock (simplified) between the LED trigger code and the power-supply code: 1) When registering a power-supply class device, power_supply_register() calls led_trigger_register() from power_supply_create_triggers() in a scoped_guard(rwsem_read, &psy->extensions_sem) context. led_trigger_register() then in turn takes a LED subsystem lock. So here we have the following locking order: * Read-lock extensions_sem * Lock LED subsystem lock(s) 2) When registering a LED class device, with its default trigger set to a power-supply LED trigger (which has already been registered) The LED class code calls power_supply_led_trigger_activate() when setting up the default trigger. power_supply_led_trigger_activate() calls power_supply_get_property() to determine the initial value of to assign to the LED and that read-locks extensions_sem. So now we have the following locking order: * Lock LED subsystem lock(s) * Read-lock extensions_sem Fixing this is easy, there is no need to hold the extensions_sem when calling power_supply_create_triggers() since all triggers are always created rather then checking for the presence of certain attributes as power_supply_add_hwmon_sysfs() does. Move power_supply_create_triggers() out of the guard block to fix this. Here is the lockdep report fixed by this change: [ 31.249343] ====================================================== [ 31.249378] WARNING: possible circular locking dependency detected [ 31.249413] 6.13.0-rc6+ #251 Tainted: G C E [ 31.249440] ------------------------------------------------------ [ 31.249471] (udev-worker)/553 is trying to acquire lock: [ 31.249501] ffff892adbcaf660 (&psy->extensions_sem){.+.+}-{4:4}, at: power_supply_get_property.part.0+0x22/0x150 [ 31.249574] but task is already holding lock: [ 31.249603] ffff892adbc0bad0 (&led_cdev->trigger_lock){+.+.}-{4:4}, at: led_trigger_set_default+0x34/0xe0 [ 31.249657] which lock already depends on the new lock. [ 31.249696] the existing dependency chain (in reverse order) is: [ 31.249735] -> #2 (&led_cdev->trigger_lock){+.+.}-{4:4}: [ 31.249778] down_write+0x3b/0xd0 [ 31.249803] led_trigger_set_default+0x34/0xe0 [ 31.249833] led_classdev_register_ext+0x311/0x3a0 [ 31.249863] input_leds_connect+0x1dc/0x2a0 [ 31.249889] input_attach_handler.isra.0+0x75/0x90 [ 31.249921] input_register_device.cold+0xa1/0x150 [ 31.249955] hidinput_connect+0x8a2/0xb80 [ 31.249982] hid_connect+0x582/0x5c0 [ 31.250007] hid_hw_start+0x3f/0x60 [ 31.250030] hid_device_probe+0x122/0x1f0 [ 31.250053] really_probe+0xde/0x340 [ 31.250080] __driver_probe_device+0x78/0x110 [ 31.250105] driver_probe_device+0x1f/0xa0 [ 31.250132] __device_attach_driver+0x85/0x110 [ 31.250160] bus_for_each_drv+0x78/0xc0 [ 31.250184] __device_attach+0xb0/0x1b0 [ 31.250207] bus_probe_device+0x94/0xb0 [ 31.250230] device_add+0x64a/0x860 [ 31.250252] hid_add_device+0xe5/0x240 [ 31.250279] usbhid_probe+0x4dc/0x620 [ 31.250303] usb_probe_interface+0xe4/0x2a0 [ 31.250329] really_probe+0xde/0x340 [ 31.250353] __driver_probe_device+0x78/0x110 [ 31.250377] driver_probe_device+0x1f/0xa0 [ 31.250404] __device_attach_driver+0x85/0x110 [ 31.250431] bus_for_each_drv+0x78/0xc0 [ 31.250455] __device_attach+0xb0/0x1b0 [ 31.250478] bus_probe_device+0x94/0xb0 [ 31.250501] device_add+0x64a/0x860 [ 31.250523] usb_set_configuration+0x606/0x8a0 [ 31.250552] usb_generic_driver_probe+0x3e/0x60 [ 31.250579] usb_probe_device+0x3d/0x120 [ 31.250605] really_probe+0xde/0x340 [ 31.250629] __driver_probe_device+0x78/0x110 [ 31.250653] driver_probe_device+0x1f/0xa0 [ 31.250680] __device_attach_driver+0x85/0x110 [ 31.250707] bus_for_each_drv+0x78/0xc0 [ 31.250731] __device_attach+0xb0/0x1b0 [ 31.250753] bus_probe_device+0x94/0xb0 [ 31.250776] device_add+0x64a/0x860 [ 31.250798] usb_new_device.cold+0x141/0x38f [ 31.250828] hub_event+0x1166/0x1980 [ 31.250854] process_one_work+0x20f/0x580 [ 31.250879] worker_thread+0x1d1/0x3b0 [ 31.250904] kthread+0xee/0x120 [ 31.250926] ret_from_fork+0x30/0x50 [ 31.250954] ret_from_fork_asm+0x1a/0x30 [ 31.250982] -> #1 (triggers_list_lock){++++}-{4:4}: [ 31.251022] down_write+0x3b/0xd0 [ 31.251045] led_trigger_register+0x40/0x1b0 [ 31.251074] power_supply_register_led_trigger+0x88/0x150 [ 31.251107] power_supply_create_triggers+0x55/0xe0 [ 31.251135] __power_supply_register.part.0+0x34e/0x4a0 [ 31.251164] devm_power_supply_register+0x70/0xc0 [ 31.251190] bq27xxx_battery_setup+0x1a1/0x6d0 [bq27xxx_battery] [ 31.251235] bq27xxx_battery_i2c_probe+0xe5/0x17f [bq27xxx_battery_i2c] [ 31.251272] i2c_device_probe+0x125/0x2b0 [ 31.251299] really_probe+0xde/0x340 [ 31.251324] __driver_probe_device+0x78/0x110 [ 31.251348] driver_probe_device+0x1f/0xa0 [ 31.251375] __driver_attach+0xba/0x1c0 [ 31.251398] bus_for_each_dev+0x6b/0xb0 [ 31.251421] bus_add_driver+0x111/0x1f0 [ 31.251445] driver_register+0x6e/0xc0 [ 31.251470] i2c_register_driver+0x41/0xb0 [ 31.251498] do_one_initcall+0x5e/0x3a0 [ 31.251522] do_init_module+0x60/0x220 [ 31.251550] __do_sys_init_module+0x15f/0x190 [ 31.251575] do_syscall_64+0x93/0x180 [ 31.251598] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 31.251629] -> #0 (&psy->extensions_sem){.+.+}-{4:4}: [ 31.251668] __lock_acquire+0x13ce/0x21c0 [ 31.251694] lock_acquire+0xcf/0x2e0 [ 31.251719] down_read+0x3e/0x170 [ 31.251741] power_supply_get_property.part.0+0x22/0x150 [ 31.251774] power_supply_update_leds+0x8d/0x230 [ 31.251804] power_supply_led_trigger_activate+0x18/0x20 [ 31.251837] led_trigger_set+0x1fc/0x300 [ 31.251863] led_trigger_set_default+0x90/0xe0 [ 31.251892] led_classdev_register_ext+0x311/0x3a0 [ 31.251921] devm_led_classdev_multicolor_register_ext+0x6e/0xb80 [led_class_multicolor] [ 31.251969] ktd202x_probe+0x464/0x5c0 [leds_ktd202x] [ 31.252002] i2c_device_probe+0x125/0x2b0 [ 31.252027] really_probe+0xde/0x340 [ 31.252052] __driver_probe_device+0x78/0x110 [ 31.252076] driver_probe_device+0x1f/0xa0 [ 31.252103] __driver_attach+0xba/0x1c0 [ 31.252125] bus_for_each_dev+0x6b/0xb0 [ 31.252148] bus_add_driver+0x111/0x1f0 [ 31.252172] driver_register+0x6e/0xc0 [ 31.252197] i2c_register_driver+0x41/0xb0 [ 31.252225] do_one_initcall+0x5e/0x3a0 [ 31.252248] do_init_module+0x60/0x220 [ 31.252274] __do_sys_init_module+0x15f/0x190 [ 31.253986] do_syscall_64+0x93/0x180 [ 31.255826] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 31.257614] other info that might help us debug this: [ 31.257619] Chain exists of: &psy->extensions_sem --> triggers_list_lock --> &led_cdev->trigger_lock [ 31.257630] Possible unsafe locking scenario: [ 31.257632] CPU0 CPU1 [ 31.257633] ---- ---- [ 31.257634] lock(&led_cdev->trigger_lock); [ 31.257637] lock(triggers_list_lock); [ 31.257640] lock(&led_cdev->trigger_lock); [ 31.257643] rlock(&psy->extensions_sem); [ 31.257646] *** DEADLOCK *** [ 31.289433] 4 locks held by (udev-worker)/553: [ 31.289443] #0: ffff892ad9658108 (&dev->mutex){....}-{4:4}, at: __driver_attach+0xaf/0x1c0 [ 31.289463] #1: ffff892adbc0bbc8 (&led_cdev->led_access){+.+.}-{4:4}, at: led_classdev_register_ext+0x1c7/0x3a0 [ 31.289476] #2: ffffffffad0e30b0 (triggers_list_lock){++++}-{4:4}, at: led_trigger_set_default+0x2c/0xe0 [ 31.289487] #3: ffff892adbc0bad0 (&led_cdev->trigger_lock){+.+.}-{4:4}, at: led_trigger_set_default+0x34/0xe0 Fixes: 6037802bbae8 ("power: supply: core: implement extension API") Cc: Thomas Weißschuh Cc: Armin Wolf Signed-off-by: Hans de Goede Reviewed-by: Thomas Weißschuh Link: https://lore.kernel.org/r/20250130140035.20636-1-hdegoede@redhat.com Signed-off-by: Sebastian Reichel --- drivers/power/supply/power_supply_core.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c index d0bb52a7a036..76c340b38015 100644 --- a/drivers/power/supply/power_supply_core.c +++ b/drivers/power/supply/power_supply_core.c @@ -1592,11 +1592,11 @@ __power_supply_register(struct device *parent, if (rc) goto register_thermal_failed; - scoped_guard(rwsem_read, &psy->extensions_sem) { - rc = power_supply_create_triggers(psy); - if (rc) - goto create_triggers_failed; + rc = power_supply_create_triggers(psy); + if (rc) + goto create_triggers_failed; + scoped_guard(rwsem_read, &psy->extensions_sem) { rc = power_supply_add_hwmon_sysfs(psy); if (rc) goto add_hwmon_sysfs_failed; From 98380110bd48fbfd6a798ee11fffff893d36062c Mon Sep 17 00:00:00 2001 From: Chris Morgan Date: Fri, 31 Jan 2025 17:14:51 -0600 Subject: [PATCH 3/3] power: supply: axp20x_battery: Fix fault handling for AXP717 Correct the fault handling for the AXP717 by changing the i2c write from regmap_update_bits() to regmap_write_bits(). The update bits function does not work properly on a RW1C register where we must write a 1 back to an existing register to clear it. Additionally, as part of this testing I confirmed the behavior of errors reappearing, so remove comment about assumptions. Fixes: 6625767049c2 ("power: supply: axp20x_battery: add support for AXP717") Signed-off-by: Chris Morgan Reviewed-by: Chen-Yu Tsai Link: https://lore.kernel.org/r/20250131231455.153447-2-macroalpha82@gmail.com Signed-off-by: Sebastian Reichel --- drivers/power/supply/axp20x_battery.c | 31 +++++++++++++-------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/power/supply/axp20x_battery.c b/drivers/power/supply/axp20x_battery.c index fa27195f074e..3c3158f31a48 100644 --- a/drivers/power/supply/axp20x_battery.c +++ b/drivers/power/supply/axp20x_battery.c @@ -466,10 +466,9 @@ static int axp717_battery_get_prop(struct power_supply *psy, /* * If a fault is detected it must also be cleared; if the - * condition persists it should reappear (This is an - * assumption, it's actually not documented). A restart was - * not sufficient to clear the bit in testing despite the - * register listed as POR. + * condition persists it should reappear. A restart was not + * sufficient to clear the bit in testing despite the register + * listed as POR. */ case POWER_SUPPLY_PROP_HEALTH: ret = regmap_read(axp20x_batt->regmap, AXP717_PMU_FAULT, @@ -480,26 +479,26 @@ static int axp717_battery_get_prop(struct power_supply *psy, switch (reg & AXP717_BATT_PMU_FAULT_MASK) { case AXP717_BATT_UVLO_2_5V: val->intval = POWER_SUPPLY_HEALTH_DEAD; - regmap_update_bits(axp20x_batt->regmap, - AXP717_PMU_FAULT, - AXP717_BATT_UVLO_2_5V, - AXP717_BATT_UVLO_2_5V); + regmap_write_bits(axp20x_batt->regmap, + AXP717_PMU_FAULT, + AXP717_BATT_UVLO_2_5V, + AXP717_BATT_UVLO_2_5V); return 0; case AXP717_BATT_OVER_TEMP: val->intval = POWER_SUPPLY_HEALTH_HOT; - regmap_update_bits(axp20x_batt->regmap, - AXP717_PMU_FAULT, - AXP717_BATT_OVER_TEMP, - AXP717_BATT_OVER_TEMP); + regmap_write_bits(axp20x_batt->regmap, + AXP717_PMU_FAULT, + AXP717_BATT_OVER_TEMP, + AXP717_BATT_OVER_TEMP); return 0; case AXP717_BATT_UNDER_TEMP: val->intval = POWER_SUPPLY_HEALTH_COLD; - regmap_update_bits(axp20x_batt->regmap, - AXP717_PMU_FAULT, - AXP717_BATT_UNDER_TEMP, - AXP717_BATT_UNDER_TEMP); + regmap_write_bits(axp20x_batt->regmap, + AXP717_PMU_FAULT, + AXP717_BATT_UNDER_TEMP, + AXP717_BATT_UNDER_TEMP); return 0; default: