From: Thomas Weißschuh linux@weissschuh.net
[ Upstream commit a231eed10ed5a290129fda36ad7bcc263c53ff7d ]
Let the power supply core register the attribute. This ensures that the attribute is created before the device is announced to userspace, avoid a race condition.
Signed-off-by: Thomas Weißschuh linux@weissschuh.net Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/battery.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index 969bf81e8d546..7f7ad94f22b91 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -678,12 +678,18 @@ static ssize_t acpi_battery_alarm_store(struct device *dev, return count; }
-static const struct device_attribute alarm_attr = { +static struct device_attribute alarm_attr = { .attr = {.name = "alarm", .mode = 0644}, .show = acpi_battery_alarm_show, .store = acpi_battery_alarm_store, };
+static struct attribute *acpi_battery_attrs[] = { + &alarm_attr.attr, + NULL +}; +ATTRIBUTE_GROUPS(acpi_battery); + /* * The Battery Hooking API * @@ -823,7 +829,10 @@ static void __exit battery_hook_exit(void)
static int sysfs_add_battery(struct acpi_battery *battery) { - struct power_supply_config psy_cfg = { .drv_data = battery, }; + struct power_supply_config psy_cfg = { + .drv_data = battery, + .attr_grp = acpi_battery_groups, + }; bool full_cap_broken = false;
if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) && @@ -868,7 +877,7 @@ static int sysfs_add_battery(struct acpi_battery *battery) return result; } battery_hook_add_battery(battery); - return device_create_file(&battery->bat->dev, &alarm_attr); + return 0; }
static void sysfs_remove_battery(struct acpi_battery *battery) @@ -879,7 +888,6 @@ static void sysfs_remove_battery(struct acpi_battery *battery) return; } battery_hook_remove_battery(battery); - device_remove_file(&battery->bat->dev, &alarm_attr); power_supply_unregister(battery->bat); battery->bat = NULL; mutex_unlock(&battery->sysfs_lock);
From: Thomas Weißschuh linux@weissschuh.net
[ Upstream commit 6bad28cfc30988a845fb3f59a99f4b8a4ce8fe95 ]
Let the power supply core register the attribute.
This ensures that the attribute is created before the device is announced to userspace, avoiding a race condition.
Signed-off-by: Thomas Weißschuh linux@weissschuh.net Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/sbs.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c index 94e3c000df2e1..fdeb46ed21d69 100644 --- a/drivers/acpi/sbs.c +++ b/drivers/acpi/sbs.c @@ -77,7 +77,6 @@ struct acpi_battery { u16 spec; u8 id; u8 present:1; - u8 have_sysfs_alarm:1; };
#define to_acpi_battery(x) power_supply_get_drvdata(x) @@ -462,12 +461,18 @@ static ssize_t acpi_battery_alarm_store(struct device *dev, return count; }
-static const struct device_attribute alarm_attr = { +static struct device_attribute alarm_attr = { .attr = {.name = "alarm", .mode = 0644}, .show = acpi_battery_alarm_show, .store = acpi_battery_alarm_store, };
+static struct attribute *acpi_battery_attrs[] = { + &alarm_attr.attr, + NULL +}; +ATTRIBUTE_GROUPS(acpi_battery); + /* -------------------------------------------------------------------------- Driver Interface -------------------------------------------------------------------------- */ @@ -518,7 +523,10 @@ static int acpi_battery_read(struct acpi_battery *battery) static int acpi_battery_add(struct acpi_sbs *sbs, int id) { struct acpi_battery *battery = &sbs->battery[id]; - struct power_supply_config psy_cfg = { .drv_data = battery, }; + struct power_supply_config psy_cfg = { + .drv_data = battery, + .attr_grp = acpi_battery_groups, + }; int result;
battery->id = id; @@ -548,10 +556,6 @@ static int acpi_battery_add(struct acpi_sbs *sbs, int id) goto end; }
- result = device_create_file(&battery->bat->dev, &alarm_attr); - if (result) - goto end; - battery->have_sysfs_alarm = 1; end: pr_info("%s [%s]: Battery Slot [%s] (battery %s)\n", ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device), @@ -563,11 +567,8 @@ static void acpi_battery_remove(struct acpi_sbs *sbs, int id) { struct acpi_battery *battery = &sbs->battery[id];
- if (battery->bat) { - if (battery->have_sysfs_alarm) - device_remove_file(&battery->bat->dev, &alarm_attr); + if (battery->bat) power_supply_unregister(battery->bat); - } }
static int acpi_charger_add(struct acpi_sbs *sbs)
From: Viresh Kumar viresh.kumar@linaro.org
[ Upstream commit 1c682593096a487fd9aebc079a307ff7a6d054a3 ]
irqfd_wakeup() gets EPOLLHUP, when it is called by eventfd_release() by way of wake_up_poll(&ctx->wqh, EPOLLHUP), which gets called under spin_lock_irqsave(). We can't use a mutex here as it will lead to a deadlock.
Fix it by switching over to a spin lock.
Reported-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Viresh Kumar viresh.kumar@linaro.org Reviewed-by: Juergen Gross jgross@suse.com Link: https://lore.kernel.org/r/a66d7a7a9001424d432f52a9fc3931a1f345464f.171870366... Signed-off-by: Juergen Gross jgross@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/xen/privcmd.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index da88173bac432..923f064c7e3e9 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -841,7 +841,7 @@ static long privcmd_ioctl_mmap_resource(struct file *file, #ifdef CONFIG_XEN_PRIVCMD_IRQFD /* Irqfd support */ static struct workqueue_struct *irqfd_cleanup_wq; -static DEFINE_MUTEX(irqfds_lock); +static DEFINE_SPINLOCK(irqfds_lock); static LIST_HEAD(irqfds_list);
struct privcmd_kernel_irqfd { @@ -905,9 +905,11 @@ irqfd_wakeup(wait_queue_entry_t *wait, unsigned int mode, int sync, void *key) irqfd_inject(kirqfd);
if (flags & EPOLLHUP) { - mutex_lock(&irqfds_lock); + unsigned long flags; + + spin_lock_irqsave(&irqfds_lock, flags); irqfd_deactivate(kirqfd); - mutex_unlock(&irqfds_lock); + spin_unlock_irqrestore(&irqfds_lock, flags); }
return 0; @@ -925,6 +927,7 @@ irqfd_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) { struct privcmd_kernel_irqfd *kirqfd, *tmp; + unsigned long flags; __poll_t events; struct fd f; void *dm_op; @@ -964,18 +967,18 @@ static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) init_waitqueue_func_entry(&kirqfd->wait, irqfd_wakeup); init_poll_funcptr(&kirqfd->pt, irqfd_poll_func);
- mutex_lock(&irqfds_lock); + spin_lock_irqsave(&irqfds_lock, flags);
list_for_each_entry(tmp, &irqfds_list, list) { if (kirqfd->eventfd == tmp->eventfd) { ret = -EBUSY; - mutex_unlock(&irqfds_lock); + spin_unlock_irqrestore(&irqfds_lock, flags); goto error_eventfd; } }
list_add_tail(&kirqfd->list, &irqfds_list); - mutex_unlock(&irqfds_lock); + spin_unlock_irqrestore(&irqfds_lock, flags);
/* * Check if there was an event already pending on the eventfd before we @@ -1007,12 +1010,13 @@ static int privcmd_irqfd_deassign(struct privcmd_irqfd *irqfd) { struct privcmd_kernel_irqfd *kirqfd; struct eventfd_ctx *eventfd; + unsigned long flags;
eventfd = eventfd_ctx_fdget(irqfd->fd); if (IS_ERR(eventfd)) return PTR_ERR(eventfd);
- mutex_lock(&irqfds_lock); + spin_lock_irqsave(&irqfds_lock, flags);
list_for_each_entry(kirqfd, &irqfds_list, list) { if (kirqfd->eventfd == eventfd) { @@ -1021,7 +1025,7 @@ static int privcmd_irqfd_deassign(struct privcmd_irqfd *irqfd) } }
- mutex_unlock(&irqfds_lock); + spin_unlock_irqrestore(&irqfds_lock, flags);
eventfd_ctx_put(eventfd);
@@ -1069,13 +1073,14 @@ static int privcmd_irqfd_init(void) static void privcmd_irqfd_exit(void) { struct privcmd_kernel_irqfd *kirqfd, *tmp; + unsigned long flags;
- mutex_lock(&irqfds_lock); + spin_lock_irqsave(&irqfds_lock, flags);
list_for_each_entry_safe(kirqfd, tmp, &irqfds_list, list) irqfd_deactivate(kirqfd);
- mutex_unlock(&irqfds_lock); + spin_unlock_irqrestore(&irqfds_lock, flags);
destroy_workqueue(irqfd_cleanup_wq); }
linux-stable-mirror@lists.linaro.org
-
Sasha Levin