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authorbibo,mao <bibo.mao@intel.com>2006-10-02 02:17:35 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-10-02 07:57:16 -0700
commit99219a3fbc2dcf2eaa954f7b2ac27299fd7894cd (patch)
tree895abde156c9fbeea9c5a87cfaaa411d4ad175c6 /arch/s390/kernel
parentf2aa85a0ccd90110e76c6375535adc3ae358f971 (diff)
[PATCH] kretprobe spinlock deadlock patch
kprobe_flush_task() possibly calls kfree function during holding kretprobe_lock spinlock, if kfree function is probed by kretprobe that will incur spinlock deadlock. This patch moves kfree function out scope of kretprobe_lock. Signed-off-by: bibo, mao <bibo.mao@intel.com> Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/s390/kernel')
-rw-r--r--arch/s390/kernel/kprobes.c9
1 files changed, 7 insertions, 2 deletions
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index ca28fb0b379..4d9ff5ce4cb 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -369,11 +369,12 @@ void __kprobes kretprobe_trampoline_holder(void)
int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kretprobe_instance *ri = NULL;
- struct hlist_head *head;
+ struct hlist_head *head, empty_rp;
struct hlist_node *node, *tmp;
unsigned long flags, orig_ret_address = 0;
unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline;
+ INIT_HLIST_HEAD(&empty_rp);
spin_lock_irqsave(&kretprobe_lock, flags);
head = kretprobe_inst_table_head(current);
@@ -399,7 +400,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
ri->rp->handler(ri, regs);
orig_ret_address = (unsigned long)ri->ret_addr;
- recycle_rp_inst(ri);
+ recycle_rp_inst(ri, &empty_rp);
if (orig_ret_address != trampoline_address) {
/*
@@ -417,6 +418,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
spin_unlock_irqrestore(&kretprobe_lock, flags);
preempt_enable_no_resched();
+ hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
+ hlist_del(&ri->hlist);
+ kfree(ri);
+ }
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we don't want the post_handler