From 683058e315f00a216fd6c79df4f63bc9945ca434 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 3 May 2013 00:26:16 +0200 Subject: ACPI / hotplug: Use device offline/online for graceful hot-removal Modify the generic ACPI hotplug code to be able to check if devices scheduled for hot-removal may be gracefully removed from the system using the device offline/online mechanism introduced previously. Namely, make acpi_scan_hot_remove() handling device hot-removal call device_offline() for all physical companions of the ACPI device nodes involved in the operation and check the results. If any of the device_offline() calls fails, the function will not progress to the removal phase (which cannot be aborted), unless its (new) force argument is set (in case of a failing offline it will put the devices offlined by it back online). In support of 'forced' device hot-removal, add a new sysfs attribute 'force_remove' that will reside under /sys/firmware/acpi/hotplug/. Signed-off-by: Rafael J. Wysocki Reviewed-by: Toshi Kani --- drivers/acpi/sysfs.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'drivers/acpi/sysfs.c') diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index fcae5fa2e1b3..5c5d1624fa2c 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -780,6 +780,33 @@ void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug, pr_err(PREFIX "Unable to add hotplug profile '%s'\n", name); } +static ssize_t force_remove_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", !!acpi_force_hot_remove); +} + +static ssize_t force_remove_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t size) +{ + bool val; + int ret; + + ret = strtobool(buf, &val); + if (ret < 0) + return ret; + + lock_device_hotplug(); + acpi_force_hot_remove = val; + unlock_device_hotplug(); + return size; +} + +static const struct kobj_attribute force_remove_attr = + __ATTR(force_remove, S_IRUGO | S_IWUSR, force_remove_show, + force_remove_store); + int __init acpi_sysfs_init(void) { int result; @@ -789,6 +816,10 @@ int __init acpi_sysfs_init(void) return result; hotplug_kobj = kobject_create_and_add("hotplug", acpi_kobj); + result = sysfs_create_file(hotplug_kobj, &force_remove_attr.attr); + if (result) + return result; + result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr); return result; } -- cgit v1.2.3 From 096a8aac6bf4a5a0b2ef812ad76d056bbf3fb2af Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Jul 2013 15:04:55 -0700 Subject: clean up scary strncpy(dst, src, strlen(src)) uses Fix various weird constructions of strncpy(dst, src, strlen(src)). Length limits should be about the space available in the destination, not repurposed as a method to either always include or always exclude a trailing NULL byte. Either the NULL should always be copied (using strlcpy), or it should not be copied (using something like memcpy). Readable code should not depend on the weird behavior of strncpy when it hits the length limit. Better to avoid the anti-pattern entirely. [akpm@linux-foundation.org: revert getdelays.c part due to missing bsd/string.h] Signed-off-by: Kees Cook Acked-by: Greg Kroah-Hartman [staging] Acked-by: Rafael J. Wysocki [acpi] Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Ursula Braun Cc: Frank Blaschka Cc: Richard Weinberger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/acpi/sysfs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/acpi/sysfs.c') diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index fcae5fa2e1b3..193745d96fcc 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -677,10 +677,9 @@ void acpi_irq_stats_init(void) else sprintf(buffer, "bug%02X", i); - name = kzalloc(strlen(buffer) + 1, GFP_KERNEL); + name = kstrdup(buffer, GFP_KERNEL); if (name == NULL) goto fail; - strncpy(name, buffer, strlen(buffer) + 1); sysfs_attr_init(&counter_attrs[i].attr); counter_attrs[i].attr.name = name; -- cgit v1.2.3