From dbe7208c6c4aec083571f2ec742870a0d0edbea3 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Sun, 7 Apr 2019 11:12:48 -0700 Subject: power: supply: cpcap-battery: Fix division by zero If called fast enough so samples do not increment, we can get division by zero in kernel: __div0 cpcap_battery_cc_raw_div cpcap_battery_get_property power_supply_get_property.part.1 power_supply_get_property power_supply_show_property power_supply_uevent Fixes: 874b2adbed12 ("power: supply: cpcap-battery: Add a battery driver") Signed-off-by: Tony Lindgren Acked-by: Pavel Machek Signed-off-by: Sebastian Reichel --- drivers/power/supply/cpcap-battery.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c index 08d5037fd052..6887870ba32c 100644 --- a/drivers/power/supply/cpcap-battery.c +++ b/drivers/power/supply/cpcap-battery.c @@ -221,6 +221,9 @@ static int cpcap_battery_cc_raw_div(struct cpcap_battery_ddata *ddata, int avg_current; u32 cc_lsb; + if (!divider) + return 0; + sample &= 0xffffff; /* 24-bits, unsigned */ offset &= 0x7ff; /* 10-bits, signed */ -- cgit From 349ced9984ff540ce74ca8a0b2e9b03dc434b9dd Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Wed, 24 Apr 2019 00:16:10 -0700 Subject: power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG Fix a similar endless event loop as was done in commit 8dcf32175b4e ("i2c: prevent endless uevent loop with CONFIG_I2C_DEBUG_CORE"): The culprit is the dev_dbg printk in the i2c uevent handler. If this is activated (for instance by CONFIG_I2C_DEBUG_CORE) it results in an endless loop with systemd-journald. This happens if user-space scans the system log and reads the uevent file to get information about a newly created device, which seems fair use to me. Unfortunately reading the "uevent" file uses the same function that runs for creating the uevent for a new device, generating the next syslog entry Both CONFIG_I2C_DEBUG_CORE and CONFIG_POWER_SUPPLY_DEBUG were reported in https://bugs.freedesktop.org/show_bug.cgi?id=76886 but only former seems to have been fixed. Drop debug prints as it was done in I2C subsystem to resolve the issue. Signed-off-by: Andrey Smirnov Cc: Chris Healy Cc: linux-pm@vger.kernel.org Signed-off-by: Sebastian Reichel --- drivers/power/supply/power_supply_sysfs.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/power/supply/power_supply_sysfs.c b/drivers/power/supply/power_supply_sysfs.c index dce24f596160..5358a80d854f 100644 --- a/drivers/power/supply/power_supply_sysfs.c +++ b/drivers/power/supply/power_supply_sysfs.c @@ -383,15 +383,11 @@ int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env) char *prop_buf; char *attrname; - dev_dbg(dev, "uevent\n"); - if (!psy || !psy->desc) { dev_dbg(dev, "No power supply yet\n"); return ret; } - dev_dbg(dev, "POWER_SUPPLY_NAME=%s\n", psy->desc->name); - ret = add_uevent_var(env, "POWER_SUPPLY_NAME=%s", psy->desc->name); if (ret) return ret; @@ -427,8 +423,6 @@ int power_supply_uevent(struct device *dev, struct kobj_uevent_env *env) goto out; } - dev_dbg(dev, "prop %s=%s\n", attrname, prop_buf); - ret = add_uevent_var(env, "POWER_SUPPLY_%s=%s", attrname, prop_buf); kfree(attrname); if (ret) -- cgit