diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 29 | ||||
| -rw-r--r-- | lib/Makefile | 1 | ||||
| -rw-r--r-- | lib/cpumask.c | 2 | ||||
| -rw-r--r-- | lib/devres.c | 28 | ||||
| -rw-r--r-- | lib/lockref.c | 3 | ||||
| -rw-r--r-- | lib/percpu-refcount.c | 86 | ||||
| -rw-r--r-- | lib/test_firmware.c | 117 |
7 files changed, 188 insertions, 78 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 24a26ad5c99d..1f630ad31fc2 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -835,7 +835,7 @@ config DEBUG_RT_MUTEXES config RT_MUTEX_TESTER bool "Built-in scriptable tester for rt-mutexes" - depends on DEBUG_KERNEL && RT_MUTEXES + depends on DEBUG_KERNEL && RT_MUTEXES && BROKEN help This option enables a rt-mutex tester. @@ -1131,20 +1131,6 @@ config PROVE_RCU_REPEATEDLY Say N if you are unsure. -config PROVE_RCU_DELAY - bool "RCU debugging: preemptible RCU race provocation" - depends on DEBUG_KERNEL && PREEMPT_RCU - default n - help - There is a class of races that involve an unlikely preemption - of __rcu_read_unlock() just after ->rcu_read_lock_nesting has - been set to INT_MIN. This feature inserts a delay at that - point to increase the probability of these races. - - Say Y to increase probability of preemption of __rcu_read_unlock(). - - Say N if you are unsure. - config SPARSE_RCU_POINTER bool "RCU debugging: sparse-based checks for pointer usage" default n @@ -1649,6 +1635,19 @@ config TEST_BPF If unsure, say N. +config TEST_FIRMWARE + tristate "Test firmware loading via userspace interface" + default n + depends on FW_LOADER + help + This builds the "test_firmware" module that creates a userspace + interface for testing firmware loading. This can be used to + control the triggering of firmware loading without needing an + actual firmware-using device. The contents can be rechecked by + userspace. + + If unsure, say N. + config TEST_UDELAY tristate "udelay test driver" default n diff --git a/lib/Makefile b/lib/Makefile index ba967a19edba..230b4b1456d6 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o obj-$(CONFIG_TEST_MODULE) += test_module.o obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o obj-$(CONFIG_TEST_BPF) += test_bpf.o +obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/cpumask.c b/lib/cpumask.c index c101230658eb..b6513a9f2892 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -191,7 +191,7 @@ int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp) i %= num_online_cpus(); - if (!cpumask_of_node(numa_node)) { + if (numa_node == -1 || !cpumask_of_node(numa_node)) { /* Use all online cpu's for non numa aware system */ cpumask_copy(mask, cpu_online_mask); } else { diff --git a/lib/devres.c b/lib/devres.c index bb632484a860..f4a195a6efe4 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -140,34 +140,6 @@ void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res) } EXPORT_SYMBOL(devm_ioremap_resource); -/** - * devm_request_and_ioremap() - Check, request region, and ioremap resource - * @dev: Generic device to handle the resource for - * @res: resource to be handled - * - * Takes all necessary steps to ioremap a mem resource. Uses managed device, so - * everything is undone on driver detach. Checks arguments, so you can feed - * it the result from e.g. platform_get_resource() directly. Returns the - * remapped pointer or NULL on error. Usage example: - * - * res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - * base = devm_request_and_ioremap(&pdev->dev, res); - * if (!base) - * return -EADDRNOTAVAIL; - */ -void __iomem *devm_request_and_ioremap(struct device *dev, - struct resource *res) -{ - void __iomem *dest_ptr; - - dest_ptr = devm_ioremap_resource(dev, res); - if (IS_ERR(dest_ptr)) - return NULL; - - return dest_ptr; -} -EXPORT_SYMBOL(devm_request_and_ioremap); - #ifdef CONFIG_HAS_IOPORT_MAP /* * Generic iomap devres diff --git a/lib/lockref.c b/lib/lockref.c index f07a40d33871..d2233de9a86e 100644 --- a/lib/lockref.c +++ b/lib/lockref.c @@ -1,6 +1,5 @@ #include <linux/export.h> #include <linux/lockref.h> -#include <linux/mutex.h> #if USE_CMPXCHG_LOCKREF @@ -29,7 +28,7 @@ if (likely(old.lock_count == prev.lock_count)) { \ SUCCESS; \ } \ - arch_mutex_cpu_relax(); \ + cpu_relax_lowlatency(); \ } \ } while (0) diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 963b7034a51b..fe5a3342e960 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -31,6 +31,11 @@ #define PCPU_COUNT_BIAS (1U << 31) +static unsigned __percpu *pcpu_count_ptr(struct percpu_ref *ref) +{ + return (unsigned __percpu *)(ref->pcpu_count_ptr & ~PCPU_REF_DEAD); +} + /** * percpu_ref_init - initialize a percpu refcount * @ref: percpu_ref to initialize @@ -46,8 +51,8 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release) { atomic_set(&ref->count, 1 + PCPU_COUNT_BIAS); - ref->pcpu_count = alloc_percpu(unsigned); - if (!ref->pcpu_count) + ref->pcpu_count_ptr = (unsigned long)alloc_percpu(unsigned); + if (!ref->pcpu_count_ptr) return -ENOMEM; ref->release = release; @@ -56,53 +61,71 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release) EXPORT_SYMBOL_GPL(percpu_ref_init); /** - * percpu_ref_cancel_init - cancel percpu_ref_init() - * @ref: percpu_ref to cancel init for + * percpu_ref_reinit - re-initialize a percpu refcount + * @ref: perpcu_ref to re-initialize * - * Once a percpu_ref is initialized, its destruction is initiated by - * percpu_ref_kill() and completes asynchronously, which can be painful to - * do when destroying a half-constructed object in init failure path. + * Re-initialize @ref so that it's in the same state as when it finished + * percpu_ref_init(). @ref must have been initialized successfully, killed + * and reached 0 but not exited. * - * This function destroys @ref without invoking @ref->release and the - * memory area containing it can be freed immediately on return. To - * prevent accidental misuse, it's required that @ref has finished - * percpu_ref_init(), whether successful or not, but never used. - * - * The weird name and usage restriction are to prevent people from using - * this function by mistake for normal shutdown instead of - * percpu_ref_kill(). + * Note that percpu_ref_tryget[_live]() are safe to perform on @ref while + * this function is in progress. */ -void percpu_ref_cancel_init(struct percpu_ref *ref) +void percpu_ref_reinit(struct percpu_ref *ref) { - unsigned __percpu *pcpu_count = ref->pcpu_count; + unsigned __percpu *pcpu_count = pcpu_count_ptr(ref); int cpu; - WARN_ON_ONCE(atomic_read(&ref->count) != 1 + PCPU_COUNT_BIAS); + BUG_ON(!pcpu_count); + WARN_ON(!percpu_ref_is_zero(ref)); + + atomic_set(&ref->count, 1 + PCPU_COUNT_BIAS); + + /* + * Restore per-cpu operation. smp_store_release() is paired with + * smp_read_barrier_depends() in __pcpu_ref_alive() and guarantees + * that the zeroing is visible to all percpu accesses which can see + * the following PCPU_REF_DEAD clearing. + */ + for_each_possible_cpu(cpu) + *per_cpu_ptr(pcpu_count, cpu) = 0; + + smp_store_release(&ref->pcpu_count_ptr, + ref->pcpu_count_ptr & ~PCPU_REF_DEAD); +} +EXPORT_SYMBOL_GPL(percpu_ref_reinit); + +/** + * percpu_ref_exit - undo percpu_ref_init() + * @ref: percpu_ref to exit + * + * This function exits @ref. The caller is responsible for ensuring that + * @ref is no longer in active use. The usual places to invoke this + * function from are the @ref->release() callback or in init failure path + * where percpu_ref_init() succeeded but other parts of the initialization + * of the embedding object failed. + */ +void percpu_ref_exit(struct percpu_ref *ref) +{ + unsigned __percpu *pcpu_count = pcpu_count_ptr(ref); if (pcpu_count) { - for_each_possible_cpu(cpu) - WARN_ON_ONCE(*per_cpu_ptr(pcpu_count, cpu)); - free_percpu(ref->pcpu_count); + free_percpu(pcpu_count); + ref->pcpu_count_ptr = PCPU_REF_DEAD; } } -EXPORT_SYMBOL_GPL(percpu_ref_cancel_init); +EXPORT_SYMBOL_GPL(percpu_ref_exit); static void percpu_ref_kill_rcu(struct rcu_head *rcu) { struct percpu_ref *ref = container_of(rcu, struct percpu_ref, rcu); - unsigned __percpu *pcpu_count = ref->pcpu_count; + unsigned __percpu *pcpu_count = pcpu_count_ptr(ref); unsigned count = 0; int cpu; - /* Mask out PCPU_REF_DEAD */ - pcpu_count = (unsigned __percpu *) - (((unsigned long) pcpu_count) & ~PCPU_STATUS_MASK); - for_each_possible_cpu(cpu) count += *per_cpu_ptr(pcpu_count, cpu); - free_percpu(pcpu_count); - pr_debug("global %i pcpu %i", atomic_read(&ref->count), (int) count); /* @@ -152,11 +175,10 @@ static void percpu_ref_kill_rcu(struct rcu_head *rcu) void percpu_ref_kill_and_confirm(struct percpu_ref *ref, percpu_ref_func_t *confirm_kill) { - WARN_ONCE(REF_STATUS(ref->pcpu_count) == PCPU_REF_DEAD, + WARN_ONCE(ref->pcpu_count_ptr & PCPU_REF_DEAD, "percpu_ref_kill() called more than once!\n"); - ref->pcpu_count = (unsigned __percpu *) - (((unsigned long) ref->pcpu_count)|PCPU_REF_DEAD); + ref->pcpu_count_ptr |= PCPU_REF_DEAD; ref->confirm_kill = confirm_kill; call_rcu_sched(&ref->rcu, percpu_ref_kill_rcu); diff --git a/lib/test_firmware.c b/lib/test_firmware.c new file mode 100644 index 000000000000..86374c1c49a4 --- /dev/null +++ b/lib/test_firmware.c @@ -0,0 +1,117 @@ +/* + * This module provides an interface to trigger and test firmware loading. + * + * It is designed to be used for basic evaluation of the firmware loading + * subsystem (for example when validating firmware verification). It lacks + * any extra dependencies, and will not normally be loaded by the system + * unless explicitly requested by name. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/printk.h> +#include <linux/firmware.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +static DEFINE_MUTEX(test_fw_mutex); +static const struct firmware *test_firmware; + +static ssize_t test_fw_misc_read(struct file *f, char __user *buf, + size_t size, loff_t *offset) +{ + ssize_t rc = 0; + + mutex_lock(&test_fw_mutex); + if (test_firmware) + rc = simple_read_from_buffer(buf, size, offset, + test_firmware->data, + test_firmware->size); + mutex_unlock(&test_fw_mutex); + return rc; +} + +static const struct file_operations test_fw_fops = { + .owner = THIS_MODULE, + .read = test_fw_misc_read, +}; + +static struct miscdevice test_fw_misc_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "test_firmware", + .fops = &test_fw_fops, +}; + +static ssize_t trigger_request_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int rc; + char *name; + + name = kzalloc(count + 1, GFP_KERNEL); + if (!name) + return -ENOSPC; + memcpy(name, buf, count); + + pr_info("loading '%s'\n", name); + + mutex_lock(&test_fw_mutex); + release_firmware(test_firmware); + test_firmware = NULL; + rc = request_firmware(&test_firmware, name, dev); + if (rc) + pr_info("load of '%s' failed: %d\n", name, rc); + pr_info("loaded: %zu\n", test_firmware ? test_firmware->size : 0); + mutex_unlock(&test_fw_mutex); + + kfree(name); + + return count; +} +static DEVICE_ATTR_WO(trigger_request); + +static int __init test_firmware_init(void) +{ + int rc; + + rc = misc_register(&test_fw_misc_device); + if (rc) { + pr_err("could not register misc device: %d\n", rc); + return rc; + } + rc = device_create_file(test_fw_misc_device.this_device, + &dev_attr_trigger_request); + if (rc) { + pr_err("could not create sysfs interface: %d\n", rc); + goto dereg; + } + + pr_warn("interface ready\n"); + + return 0; +dereg: + misc_deregister(&test_fw_misc_device); + return rc; +} + +module_init(test_firmware_init); + +static void __exit test_firmware_exit(void) +{ + release_firmware(test_firmware); + device_remove_file(test_fw_misc_device.this_device, + &dev_attr_trigger_request); + misc_deregister(&test_fw_misc_device); + pr_warn("removed interface\n"); +} + +module_exit(test_firmware_exit); + +MODULE_AUTHOR("Kees Cook <keescook@chromium.org>"); +MODULE_LICENSE("GPL"); |