summaryrefslogtreecommitdiff
path: root/kernel/kprobes.c
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-11-16 11:18:46 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-11-16 11:18:46 +0300
commit93c69b2d17372463ae33b79b3002c22a208945b3 (patch)
tree328d30d717710d830633337ada90a65d65095eda /kernel/kprobes.c
parentef84928cff589c6b42e16b3ef7d2d95469128c80 (diff)
parent09162bc32c880a791c6c0668ce0745cf7958f576 (diff)
downloadlinux-93c69b2d17372463ae33b79b3002c22a208945b3.tar.xz
Merge 5.10-rc4 into char-misc-next
We need the char/misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/kprobes.c')
-rw-r--r--kernel/kprobes.c25
1 files changed, 21 insertions, 4 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 8a12a25fa40d..41fdbb7953c6 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1249,7 +1249,13 @@ __acquires(hlist_lock)
*head = &kretprobe_inst_table[hash];
hlist_lock = kretprobe_table_lock_ptr(hash);
- raw_spin_lock_irqsave(hlist_lock, *flags);
+ /*
+ * Nested is a workaround that will soon not be needed.
+ * There's other protections that make sure the same lock
+ * is not taken on the same CPU that lockdep is unaware of.
+ * Differentiate when it is taken in NMI context.
+ */
+ raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi());
}
NOKPROBE_SYMBOL(kretprobe_hash_lock);
@@ -1258,7 +1264,13 @@ static void kretprobe_table_lock(unsigned long hash,
__acquires(hlist_lock)
{
raw_spinlock_t *hlist_lock = kretprobe_table_lock_ptr(hash);
- raw_spin_lock_irqsave(hlist_lock, *flags);
+ /*
+ * Nested is a workaround that will soon not be needed.
+ * There's other protections that make sure the same lock
+ * is not taken on the same CPU that lockdep is unaware of.
+ * Differentiate when it is taken in NMI context.
+ */
+ raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi());
}
NOKPROBE_SYMBOL(kretprobe_table_lock);
@@ -2028,7 +2040,12 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
/* TODO: consider to only swap the RA after the last pre_handler fired */
hash = hash_ptr(current, KPROBE_HASH_BITS);
- raw_spin_lock_irqsave(&rp->lock, flags);
+ /*
+ * Nested is a workaround that will soon not be needed.
+ * There's other protections that make sure the same lock
+ * is not taken on the same CPU that lockdep is unaware of.
+ */
+ raw_spin_lock_irqsave_nested(&rp->lock, flags, 1);
if (!hlist_empty(&rp->free_instances)) {
ri = hlist_entry(rp->free_instances.first,
struct kretprobe_instance, hlist);
@@ -2039,7 +2056,7 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
ri->task = current;
if (rp->entry_handler && rp->entry_handler(ri, regs)) {
- raw_spin_lock_irqsave(&rp->lock, flags);
+ raw_spin_lock_irqsave_nested(&rp->lock, flags, 1);
hlist_add_head(&ri->hlist, &rp->free_instances);
raw_spin_unlock_irqrestore(&rp->lock, flags);
return 0;