diff options
author | Lan Tianyu <tianyu.lan@intel.com> | 2011-06-30 11:34:12 +0800 |
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committer | Len Brown <len.brown@intel.com> | 2011-07-14 00:06:19 -0400 |
commit | 9c921c22a7f33397a6774d7fa076db9b6a0fd669 (patch) | |
tree | ca32ce369889d8a2f0b2e5f242dd0dd670ca3376 | |
parent | 6e17fb6aa1a67afa1827ae317c3594040f055730 (diff) | |
download | lwn-9c921c22a7f33397a6774d7fa076db9b6a0fd669.tar.gz lwn-9c921c22a7f33397a6774d7fa076db9b6a0fd669.zip |
ACPI / Battery: Resolve the race condition in the sysfs_remove_battery()
Use battery->lock in sysfs_remove_battery() to make
checking, removing, and clearing bat.dev atomic.
This is necessary because sysfs_remove_battery() may
be invoked concurrently from different paths.
https://bugzilla.kernel.org/show_bug.cgi?id=35642
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
-rw-r--r-- | drivers/acpi/battery.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index 4ba339d0ea19..40bf01d42cc3 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -573,11 +573,16 @@ static int sysfs_add_battery(struct acpi_battery *battery) static void sysfs_remove_battery(struct acpi_battery *battery) { - if (!battery->bat.dev) + mutex_lock(&battery->lock); + if (!battery->bat.dev) { + mutex_unlock(&battery->lock); return; + } + device_remove_file(battery->bat.dev, &alarm_attr); power_supply_unregister(&battery->bat); battery->bat.dev = NULL; + mutex_unlock(&battery->lock); } /* |