#include <linux/cn_proc.h>
#include <linux/compiler.h>
#include <linux/posix-timers.h>
-#include <linux/livepatch.h>
#include <linux/cgroup.h>
#include <linux/audit.h>
void recalc_sigpending(void)
{
- if (!recalc_sigpending_tsk(current) && !freezing(current) &&
- !klp_patch_pending(current))
+ if (!recalc_sigpending_tsk(current) && !freezing(current))
clear_thread_flag(TIF_SIGPENDING);
}
* appropriate lock must be held to stop the target task from exiting
*/
static struct sigqueue *
-__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit)
+__sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags,
+ int override_rlimit, const unsigned int sigqueue_flags)
{
struct sigqueue *q = NULL;
struct user_struct *user;
rcu_read_unlock();
if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
- q = kmem_cache_alloc(sigqueue_cachep, flags);
+ /*
+ * Preallocation does not hold sighand::siglock so it can't
+ * use the cache. The lockless caching requires that only
+ * one consumer and only one producer run at a time.
+ */
+ q = READ_ONCE(t->sigqueue_cache);
+ if (!q || sigqueue_flags)
+ q = kmem_cache_alloc(sigqueue_cachep, gfp_flags);
+ else
+ WRITE_ONCE(t->sigqueue_cache, NULL);
} else {
print_dropped_signal(sig);
}
free_uid(user);
} else {
INIT_LIST_HEAD(&q->list);
- q->flags = 0;
+ q->flags = sigqueue_flags;
q->user = user;
}
return q;
}
+void exit_task_sigqueue_cache(struct task_struct *tsk)
+{
+ /* Race free because @tsk is mopped up */
+ struct sigqueue *q = tsk->sigqueue_cache;
+
+ if (q) {
+ tsk->sigqueue_cache = NULL;
+ /*
+ * Hand it back to the cache as the task might
+ * be self reaping which would leak the object.
+ */
+ kmem_cache_free(sigqueue_cachep, q);
+ }
+}
+
+static void sigqueue_cache_or_free(struct sigqueue *q)
+{
+ /*
+ * Cache one sigqueue per task. This pairs with the consumer side
+ * in __sigqueue_alloc() and needs READ/WRITE_ONCE() to prevent the
+ * compiler from store tearing and to tell KCSAN that the data race
+ * is intentional when run without holding current->sighand->siglock,
+ * which is fine as current obviously cannot run __sigqueue_free()
+ * concurrently.
+ */
+ if (!READ_ONCE(current->sigqueue_cache))
+ WRITE_ONCE(current->sigqueue_cache, q);
+ else
+ kmem_cache_free(sigqueue_cachep, q);
+}
+
static void __sigqueue_free(struct sigqueue *q)
{
if (q->flags & SIGQUEUE_PREALLOC)
return;
if (atomic_dec_and_test(&q->user->sigpending))
free_uid(q->user);
- kmem_cache_free(sigqueue_cachep, q);
+ sigqueue_cache_or_free(q);
}
void flush_sigqueue(struct sigpending *queue)
else
override_rlimit = 0;
- q = __sigqueue_alloc(sig, t, GFP_ATOMIC, override_rlimit);
+ q = __sigqueue_alloc(sig, t, GFP_ATOMIC, override_rlimit, 0);
+
if (q) {
list_add_tail(&q->list, &pending->list);
switch ((unsigned long) info) {
case SIL_TIMER:
case SIL_POLL:
case SIL_FAULT:
+ case SIL_FAULT_TRAPNO:
case SIL_FAULT_MCEERR:
case SIL_FAULT_BNDERR:
case SIL_FAULT_PKUERR:
+ case SIL_PERF_EVENT:
case SIL_SYS:
ret = false;
break;
}
#endif
+int force_sig_perf(void __user *addr, u32 type, u64 sig_data)
+{
+ struct kernel_siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = SIGTRAP;
+ info.si_errno = 0;
+ info.si_code = TRAP_PERF;
+ info.si_addr = addr;
+ info.si_perf_data = sig_data;
+ info.si_perf_type = type;
+
+ return force_sig_info(&info);
+}
+
/* For the crazy architectures that include trap information in
* the errno field, instead of an actual errno value.
*/
*/
struct sigqueue *sigqueue_alloc(void)
{
- struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0);
-
- if (q)
- q->flags |= SIGQUEUE_PREALLOC;
-
- return q;
+ return __sigqueue_alloc(-1, current, GFP_KERNEL, 0, SIGQUEUE_PREALLOC);
}
void sigqueue_free(struct sigqueue *q)
{
switch (siginfo_layout(ksig->sig, ksig->info.si_code)) {
case SIL_FAULT:
+ case SIL_FAULT_TRAPNO:
case SIL_FAULT_MCEERR:
case SIL_FAULT_BNDERR:
case SIL_FAULT_PKUERR:
+ case SIL_PERF_EVENT:
ksig->info.si_addr = arch_untagged_si_addr(
ksig->info.si_addr, ksig->sig, ksig->info.si_code);
break;
#ifdef SEGV_PKUERR
else if ((sig == SIGSEGV) && (si_code == SEGV_PKUERR))
layout = SIL_FAULT_PKUERR;
+#endif
+ else if ((sig == SIGTRAP) && (si_code == TRAP_PERF))
+ layout = SIL_PERF_EVENT;
+#ifdef __ARCH_SI_TRAPNO
+ else if (layout == SIL_FAULT)
+ layout = SIL_FAULT_TRAPNO;
#endif
}
else if (si_code <= NSIGPOLL)
break;
case SIL_FAULT:
to->si_addr = ptr_to_compat(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
+ break;
+ case SIL_FAULT_TRAPNO:
+ to->si_addr = ptr_to_compat(from->si_addr);
to->si_trapno = from->si_trapno;
-#endif
break;
case SIL_FAULT_MCEERR:
to->si_addr = ptr_to_compat(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_addr_lsb = from->si_addr_lsb;
break;
case SIL_FAULT_BNDERR:
to->si_addr = ptr_to_compat(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_lower = ptr_to_compat(from->si_lower);
to->si_upper = ptr_to_compat(from->si_upper);
break;
case SIL_FAULT_PKUERR:
to->si_addr = ptr_to_compat(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_pkey = from->si_pkey;
break;
+ case SIL_PERF_EVENT:
+ to->si_addr = ptr_to_compat(from->si_addr);
+ to->si_perf_data = from->si_perf_data;
+ to->si_perf_type = from->si_perf_type;
+ break;
case SIL_CHLD:
to->si_pid = from->si_pid;
to->si_uid = from->si_uid;
break;
case SIL_FAULT:
to->si_addr = compat_ptr(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
+ break;
+ case SIL_FAULT_TRAPNO:
+ to->si_addr = compat_ptr(from->si_addr);
to->si_trapno = from->si_trapno;
-#endif
break;
case SIL_FAULT_MCEERR:
to->si_addr = compat_ptr(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_addr_lsb = from->si_addr_lsb;
break;
case SIL_FAULT_BNDERR:
to->si_addr = compat_ptr(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_lower = compat_ptr(from->si_lower);
to->si_upper = compat_ptr(from->si_upper);
break;
case SIL_FAULT_PKUERR:
to->si_addr = compat_ptr(from->si_addr);
-#ifdef __ARCH_SI_TRAPNO
- to->si_trapno = from->si_trapno;
-#endif
to->si_pkey = from->si_pkey;
break;
+ case SIL_PERF_EVENT:
+ to->si_addr = compat_ptr(from->si_addr);
+ to->si_perf_data = from->si_perf_data;
+ to->si_perf_type = from->si_perf_type;
+ break;
case SIL_CHLD:
to->si_pid = from->si_pid;
to->si_uid = from->si_uid;
/* sigfault */
CHECK_OFFSET(si_addr);
+ CHECK_OFFSET(si_trapno);
CHECK_OFFSET(si_addr_lsb);
CHECK_OFFSET(si_lower);
CHECK_OFFSET(si_upper);
CHECK_OFFSET(si_pkey);
+ CHECK_OFFSET(si_perf_data);
+ CHECK_OFFSET(si_perf_type);
/* sigpoll */
CHECK_OFFSET(si_band);
projects / linux-2.6-microblaze.git / blobdiff