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-rw-r--r--kernel/Kconfig.locks2
-rw-r--r--kernel/auditsc.c27
-rw-r--r--kernel/pm_qos_params.c2
-rw-r--r--kernel/sysctl.c12
-rw-r--r--kernel/watchdog.c52
5 files changed, 57 insertions, 38 deletions
diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks
index 88c92fb4461..5068e2a4e75 100644
--- a/kernel/Kconfig.locks
+++ b/kernel/Kconfig.locks
@@ -199,4 +199,4 @@ config INLINE_WRITE_UNLOCK_IRQRESTORE
def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
config MUTEX_SPIN_ON_OWNER
- def_bool SMP && !DEBUG_MUTEXES && !HAVE_DEFAULT_NO_SPIN_MUTEXES
+ def_bool SMP && !DEBUG_MUTEXES
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index b33513a08be..00d79df03e7 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -443,17 +443,25 @@ static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
/* Determine if any context name data matches a rule's watch data */
/* Compare a task_struct with an audit_rule. Return 1 on match, 0
- * otherwise. */
+ * otherwise.
+ *
+ * If task_creation is true, this is an explicit indication that we are
+ * filtering a task rule at task creation time. This and tsk == current are
+ * the only situations where tsk->cred may be accessed without an rcu read lock.
+ */
static int audit_filter_rules(struct task_struct *tsk,
struct audit_krule *rule,
struct audit_context *ctx,
struct audit_names *name,
- enum audit_state *state)
+ enum audit_state *state,
+ bool task_creation)
{
- const struct cred *cred = get_task_cred(tsk);
+ const struct cred *cred;
int i, j, need_sid = 1;
u32 sid;
+ cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
+
for (i = 0; i < rule->field_count; i++) {
struct audit_field *f = &rule->fields[i];
int result = 0;
@@ -637,10 +645,8 @@ static int audit_filter_rules(struct task_struct *tsk,
break;
}
- if (!result) {
- put_cred(cred);
+ if (!result)
return 0;
- }
}
if (ctx) {
@@ -656,7 +662,6 @@ static int audit_filter_rules(struct task_struct *tsk,
case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
}
- put_cred(cred);
return 1;
}
@@ -671,7 +676,8 @@ static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
rcu_read_lock();
list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
- if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
+ if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
+ &state, true)) {
if (state == AUDIT_RECORD_CONTEXT)
*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
rcu_read_unlock();
@@ -705,7 +711,7 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
list_for_each_entry_rcu(e, list, list) {
if ((e->rule.mask[word] & bit) == bit &&
audit_filter_rules(tsk, &e->rule, ctx, NULL,
- &state)) {
+ &state, false)) {
rcu_read_unlock();
ctx->current_state = state;
return state;
@@ -743,7 +749,8 @@ void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
list_for_each_entry_rcu(e, list, list) {
if ((e->rule.mask[word] & bit) == bit &&
- audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
+ audit_filter_rules(tsk, &e->rule, ctx, n,
+ &state, false)) {
rcu_read_unlock();
ctx->current_state = state;
return;
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 0da058bff8e..beb184689af 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -385,7 +385,7 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf,
s32 value;
unsigned long flags;
struct pm_qos_object *o;
- struct pm_qos_request_list *pm_qos_req = filp->private_data;;
+ struct pm_qos_request_list *pm_qos_req = filp->private_data;
if (!pm_qos_req)
return -EINVAL;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index c0bb32414b1..3dd0c46fa3b 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -730,14 +730,16 @@ static struct ctl_table kern_table[] = {
.data = &watchdog_enabled,
.maxlen = sizeof (int),
.mode = 0644,
- .proc_handler = proc_dowatchdog_enabled,
+ .proc_handler = proc_dowatchdog,
+ .extra1 = &zero,
+ .extra2 = &one,
},
{
.procname = "watchdog_thresh",
- .data = &softlockup_thresh,
+ .data = &watchdog_thresh,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dowatchdog_thresh,
+ .proc_handler = proc_dowatchdog,
.extra1 = &neg_one,
.extra2 = &sixty,
},
@@ -755,7 +757,9 @@ static struct ctl_table kern_table[] = {
.data = &watchdog_enabled,
.maxlen = sizeof (int),
.mode = 0644,
- .proc_handler = proc_dowatchdog_enabled,
+ .proc_handler = proc_dowatchdog,
+ .extra1 = &zero,
+ .extra2 = &one,
},
#endif
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 14733d4d156..6e63097fa73 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -28,7 +28,7 @@
#include <linux/perf_event.h>
int watchdog_enabled = 1;
-int __read_mostly softlockup_thresh = 60;
+int __read_mostly watchdog_thresh = 10;
static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts);
static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog);
@@ -91,6 +91,17 @@ static int __init nosoftlockup_setup(char *str)
__setup("nosoftlockup", nosoftlockup_setup);
/* */
+/*
+ * Hard-lockup warnings should be triggered after just a few seconds. Soft-
+ * lockups can have false positives under extreme conditions. So we generally
+ * want a higher threshold for soft lockups than for hard lockups. So we couple
+ * the thresholds with a factor: we make the soft threshold twice the amount of
+ * time the hard threshold is.
+ */
+static int get_softlockup_thresh()
+{
+ return watchdog_thresh * 2;
+}
/*
* Returns seconds, approximately. We don't need nanosecond
@@ -105,12 +116,12 @@ static unsigned long get_timestamp(int this_cpu)
static unsigned long get_sample_period(void)
{
/*
- * convert softlockup_thresh from seconds to ns
+ * convert watchdog_thresh from seconds to ns
* the divide by 5 is to give hrtimer 5 chances to
* increment before the hardlockup detector generates
* a warning
*/
- return softlockup_thresh / 5 * NSEC_PER_SEC;
+ return get_softlockup_thresh() * (NSEC_PER_SEC / 5);
}
/* Commands for resetting the watchdog */
@@ -182,7 +193,7 @@ static int is_softlockup(unsigned long touch_ts)
unsigned long now = get_timestamp(smp_processor_id());
/* Warn about unreasonable delays: */
- if (time_after(now, touch_ts + softlockup_thresh))
+ if (time_after(now, touch_ts + get_softlockup_thresh()))
return now - touch_ts;
return 0;
@@ -359,7 +370,7 @@ static int watchdog_nmi_enable(int cpu)
/* Try to register using hardware perf events */
wd_attr = &wd_hw_attr;
- wd_attr->sample_period = hw_nmi_get_sample_period();
+ wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh);
event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback);
if (!IS_ERR(event)) {
printk(KERN_INFO "NMI watchdog enabled, takes one hw-pmu counter.\n");
@@ -501,28 +512,25 @@ static void watchdog_disable_all_cpus(void)
/* sysctl functions */
#ifdef CONFIG_SYSCTL
/*
- * proc handler for /proc/sys/kernel/nmi_watchdog
+ * proc handler for /proc/sys/kernel/nmi_watchdog,watchdog_thresh
*/
-int proc_dowatchdog_enabled(struct ctl_table *table, int write,
- void __user *buffer, size_t *length, loff_t *ppos)
+int proc_dowatchdog(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
- proc_dointvec(table, write, buffer, length, ppos);
+ int ret;
- if (write) {
- if (watchdog_enabled)
- watchdog_enable_all_cpus();
- else
- watchdog_disable_all_cpus();
- }
- return 0;
-}
+ ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+ if (ret || !write)
+ goto out;
-int proc_dowatchdog_thresh(struct ctl_table *table, int write,
- void __user *buffer,
- size_t *lenp, loff_t *ppos)
-{
- return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+ if (watchdog_enabled && watchdog_thresh)
+ watchdog_enable_all_cpus();
+ else
+ watchdog_disable_all_cpus();
+
+out:
+ return ret;
}
#endif /* CONFIG_SYSCTL */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-06 16:21:28 +0000