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-rw-r--r--kernel/cgroup/cgroup.c5
-rw-r--r--kernel/cgroup/cpuset.c4
-rw-r--r--kernel/events/core.c21
-rw-r--r--kernel/power/process.c2
-rw-r--r--kernel/power/suspend.c29
-rw-r--r--kernel/printk/printk.c46
-rw-r--r--kernel/rcu/srcu.c5
-rw-r--r--kernel/rcu/srcutiny.c7
-rw-r--r--kernel/rcu/srcutree.c5
9 files changed, 51 insertions, 73 deletions
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index c3c9a0e1b3c9..8d4e85eae42c 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4265,6 +4265,11 @@ static void kill_css(struct cgroup_subsys_state *css)
{
lockdep_assert_held(&cgroup_mutex);
+ if (css->flags & CSS_DYING)
+ return;
+
+ css->flags |= CSS_DYING;
+
/*
* This must happen before css is disassociated with its cgroup.
* See seq_css() for details.
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index f6501f4f6040..ae643412948a 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -176,9 +176,9 @@ typedef enum {
} cpuset_flagbits_t;
/* convenient tests for these bits */
-static inline bool is_cpuset_online(const struct cpuset *cs)
+static inline bool is_cpuset_online(struct cpuset *cs)
{
- return test_bit(CS_ONLINE, &cs->flags);
+ return test_bit(CS_ONLINE, &cs->flags) && !css_is_dying(&cs->css);
}
static inline int is_cpu_exclusive(const struct cpuset *cs)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6e75a5c9412d..6c4e523dc1e2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7316,6 +7316,21 @@ int perf_event_account_interrupt(struct perf_event *event)
return __perf_event_account_interrupt(event, 1);
}
+static bool sample_is_allowed(struct perf_event *event, struct pt_regs *regs)
+{
+ /*
+ * Due to interrupt latency (AKA "skid"), we may enter the
+ * kernel before taking an overflow, even if the PMU is only
+ * counting user events.
+ * To avoid leaking information to userspace, we must always
+ * reject kernel samples when exclude_kernel is set.
+ */
+ if (event->attr.exclude_kernel && !user_mode(regs))
+ return false;
+
+ return true;
+}
+
/*
* Generic event overflow handling, sampling.
*/
@@ -7337,6 +7352,12 @@ static int __perf_event_overflow(struct perf_event *event,
ret = __perf_event_account_interrupt(event, throttle);
/*
+ * For security, drop the skid kernel samples if necessary.
+ */
+ if (!sample_is_allowed(event, regs))
+ return ret;
+
+ /*
* XXX event_limit might not quite work as expected on inherited
* events
*/
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 78672d324a6e..c7209f060eeb 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -132,7 +132,7 @@ int freeze_processes(void)
if (!pm_freezing)
atomic_inc(&system_freezing_cnt);
- pm_wakeup_clear(true);
+ pm_wakeup_clear();
pr_info("Freezing user space processes ... ");
pm_freezing = true;
error = try_to_freeze_tasks(true);
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index c0248c74d6d4..15e6baef5c73 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -72,8 +72,6 @@ static void freeze_begin(void)
static void freeze_enter(void)
{
- trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, true);
-
spin_lock_irq(&suspend_freeze_lock);
if (pm_wakeup_pending())
goto out;
@@ -100,27 +98,6 @@ static void freeze_enter(void)
out:
suspend_freeze_state = FREEZE_STATE_NONE;
spin_unlock_irq(&suspend_freeze_lock);
-
- trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, false);
-}
-
-static void s2idle_loop(void)
-{
- do {
- freeze_enter();
-
- if (freeze_ops && freeze_ops->wake)
- freeze_ops->wake();
-
- dpm_resume_noirq(PMSG_RESUME);
- if (freeze_ops && freeze_ops->sync)
- freeze_ops->sync();
-
- if (pm_wakeup_pending())
- break;
-
- pm_wakeup_clear(false);
- } while (!dpm_suspend_noirq(PMSG_SUSPEND));
}
void freeze_wake(void)
@@ -394,8 +371,10 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
* all the devices are suspended.
*/
if (state == PM_SUSPEND_FREEZE) {
- s2idle_loop();
- goto Platform_early_resume;
+ trace_suspend_resume(TPS("machine_suspend"), state, true);
+ freeze_enter();
+ trace_suspend_resume(TPS("machine_suspend"), state, false);
+ goto Platform_wake;
}
error = disable_nonboot_cpus();
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index a1aecf44ab07..a1db38abac5b 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -269,7 +269,6 @@ static struct console *exclusive_console;
#define MAX_CMDLINECONSOLES 8
static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES];
-static int console_cmdline_cnt;
static int preferred_console = -1;
int console_set_on_cmdline;
@@ -1906,25 +1905,12 @@ static int __add_preferred_console(char *name, int idx, char *options,
* See if this tty is not yet registered, and
* if we have a slot free.
*/
- for (i = 0, c = console_cmdline; i < console_cmdline_cnt; i++, c++) {
+ for (i = 0, c = console_cmdline;
+ i < MAX_CMDLINECONSOLES && c->name[0];
+ i++, c++) {
if (strcmp(c->name, name) == 0 && c->index == idx) {
- if (brl_options)
- return 0;
-
- /*
- * Maintain an invariant that will help to find if
- * the matching console is preferred, see
- * register_console():
- *
- * The last non-braille console is always
- * the preferred one.
- */
- if (i != console_cmdline_cnt - 1)
- swap(console_cmdline[i],
- console_cmdline[console_cmdline_cnt - 1]);
-
- preferred_console = console_cmdline_cnt - 1;
-
+ if (!brl_options)
+ preferred_console = i;
return 0;
}
}
@@ -1937,7 +1923,6 @@ static int __add_preferred_console(char *name, int idx, char *options,
braille_set_options(c, brl_options);
c->index = idx;
- console_cmdline_cnt++;
return 0;
}
/*
@@ -2477,23 +2462,12 @@ void register_console(struct console *newcon)
}
/*
- * See if this console matches one we selected on the command line.
- *
- * There may be several entries in the console_cmdline array matching
- * with the same console, one with newcon->match(), another by
- * name/index:
- *
- * pl011,mmio,0x87e024000000,115200 -- added from SPCR
- * ttyAMA0 -- added from command line
- *
- * Traverse the console_cmdline array in reverse order to be
- * sure that if this console is preferred then it will be the first
- * matching entry. We use the invariant that is maintained in
- * __add_preferred_console().
+ * See if this console matches one we selected on
+ * the command line.
*/
- for (i = console_cmdline_cnt - 1; i >= 0; i--) {
- c = console_cmdline + i;
-
+ for (i = 0, c = console_cmdline;
+ i < MAX_CMDLINECONSOLES && c->name[0];
+ i++, c++) {
if (!newcon->match ||
newcon->match(newcon, c->name, c->index, c->options) != 0) {
/* default matching */
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index 584d8a983883..dea03614263f 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -263,7 +263,7 @@ EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
/*
* Counts the new reader in the appropriate per-CPU element of the
- * srcu_struct. Must be called from process context.
+ * srcu_struct.
* Returns an index that must be passed to the matching srcu_read_unlock().
*/
int __srcu_read_lock(struct srcu_struct *sp)
@@ -271,7 +271,7 @@ int __srcu_read_lock(struct srcu_struct *sp)
int idx;
idx = READ_ONCE(sp->completed) & 0x1;
- __this_cpu_inc(sp->per_cpu_ref->lock_count[idx]);
+ this_cpu_inc(sp->per_cpu_ref->lock_count[idx]);
smp_mb(); /* B */ /* Avoid leaking the critical section. */
return idx;
}
@@ -281,7 +281,6 @@ EXPORT_SYMBOL_GPL(__srcu_read_lock);
* Removes the count for the old reader from the appropriate per-CPU
* element of the srcu_struct. Note that this may well be a different
* CPU than that which was incremented by the corresponding srcu_read_lock().
- * Must be called from process context.
*/
void __srcu_read_unlock(struct srcu_struct *sp, int idx)
{
diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c
index 36e1f82faed1..32798eb14853 100644
--- a/kernel/rcu/srcutiny.c
+++ b/kernel/rcu/srcutiny.c
@@ -97,8 +97,9 @@ EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
/*
* Counts the new reader in the appropriate per-CPU element of the
- * srcu_struct. Must be called from process context.
- * Returns an index that must be passed to the matching srcu_read_unlock().
+ * srcu_struct. Can be invoked from irq/bh handlers, but the matching
+ * __srcu_read_unlock() must be in the same handler instance. Returns an
+ * index that must be passed to the matching srcu_read_unlock().
*/
int __srcu_read_lock(struct srcu_struct *sp)
{
@@ -112,7 +113,7 @@ EXPORT_SYMBOL_GPL(__srcu_read_lock);
/*
* Removes the count for the old reader from the appropriate element of
- * the srcu_struct. Must be called from process context.
+ * the srcu_struct.
*/
void __srcu_read_unlock(struct srcu_struct *sp, int idx)
{
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 3ae8474557df..157654fa436a 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -357,7 +357,7 @@ EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
/*
* Counts the new reader in the appropriate per-CPU element of the
- * srcu_struct. Must be called from process context.
+ * srcu_struct.
* Returns an index that must be passed to the matching srcu_read_unlock().
*/
int __srcu_read_lock(struct srcu_struct *sp)
@@ -365,7 +365,7 @@ int __srcu_read_lock(struct srcu_struct *sp)
int idx;
idx = READ_ONCE(sp->srcu_idx) & 0x1;
- __this_cpu_inc(sp->sda->srcu_lock_count[idx]);
+ this_cpu_inc(sp->sda->srcu_lock_count[idx]);
smp_mb(); /* B */ /* Avoid leaking the critical section. */
return idx;
}
@@ -375,7 +375,6 @@ EXPORT_SYMBOL_GPL(__srcu_read_lock);
* Removes the count for the old reader from the appropriate per-CPU
* element of the srcu_struct. Note that this may well be a different
* CPU than that which was incremented by the corresponding srcu_read_lock().
- * Must be called from process context.
*/
void __srcu_read_unlock(struct srcu_struct *sp, int idx)
{
generated by cgit (git 2.34.1) at 2024-05-10 18:50:50 +0000