Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"A kprobes and a perf compat ioctl fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Handle compat ioctl
kprobes: Skip kretprobe hit in NMI context to avoid deadlock
+34
-2
+22
-1
kernel/events/core.c
+22
-1
kernel/events/core.c
···
41
41
#include <linux/cgroup.h>
42
42
#include <linux/module.h>
43
43
#include <linux/mman.h>
44
+
#include <linux/compat.h>
44
45
45
46
#include "internal.h"
46
47
···
3718
3717
return 0;
3719
3718
}
3720
3719
3720
+
#ifdef CONFIG_COMPAT
3721
+
static long perf_compat_ioctl(struct file *file, unsigned int cmd,
3722
+
unsigned long arg)
3723
+
{
3724
+
switch (_IOC_NR(cmd)) {
3725
+
case _IOC_NR(PERF_EVENT_IOC_SET_FILTER):
3726
+
case _IOC_NR(PERF_EVENT_IOC_ID):
3727
+
/* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */
3728
+
if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
3729
+
cmd &= ~IOCSIZE_MASK;
3730
+
cmd |= sizeof(void *) << IOCSIZE_SHIFT;
3731
+
}
3732
+
break;
3733
+
}
3734
+
return perf_ioctl(file, cmd, arg);
3735
+
}
3736
+
#else
3737
+
# define perf_compat_ioctl NULL
3738
+
#endif
3739
+
3721
3740
int perf_event_task_enable(void)
3722
3741
{
3723
3742
struct perf_event *event;
···
4243
4222
.read = perf_read,
4244
4223
.poll = perf_poll,
4245
4224
.unlocked_ioctl = perf_ioctl,
4246
-
.compat_ioctl = perf_ioctl,
4225
+
.compat_ioctl = perf_compat_ioctl,
4247
4226
.mmap = perf_mmap,
4248
4227
.fasync = perf_fasync,
4249
4228
};
+12
-1
kernel/kprobes.c
+12
-1
kernel/kprobes.c
···
1778
1778
unsigned long hash, flags = 0;
1779
1779
struct kretprobe_instance *ri;
1780
1780
1781
-
/*TODO: consider to only swap the RA after the last pre_handler fired */
1781
+
/*
1782
+
* To avoid deadlocks, prohibit return probing in NMI contexts,
1783
+
* just skip the probe and increase the (inexact) 'nmissed'
1784
+
* statistical counter, so that the user is informed that
1785
+
* something happened:
1786
+
*/
1787
+
if (unlikely(in_nmi())) {
1788
+
rp->nmissed++;
1789
+
return 0;
1790
+
}
1791
+
1792
+
/* TODO: consider to only swap the RA after the last pre_handler fired */
1782
1793
hash = hash_ptr(current, KPROBE_HASH_BITS);
1783
1794
raw_spin_lock_irqsave(&rp->lock, flags);
1784
1795
if (!hlist_empty(&rp->free_instances)) {