sh: kprobes: Fix up race against probe point removal.

Handle a corner case where another CPU or debugger removes the probe
point from underneath us.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Paul Mundt 2008-09-08 18:15:55 +09:00
parent 247bc6d2ae
commit 734db3770d

View File

@ -252,6 +252,17 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
p = get_kprobe(addr);
if (!p) {
/* Not one of ours: let kernel handle it */
if (*(kprobe_opcode_t *)addr != BREAKPOINT_INSTRUCTION) {
/*
* The breakpoint instruction was removed right
* after we hit it. Another cpu has removed
* either a probepoint or a debugger breakpoint
* at this address. In either case, no further
* handling of this interrupt is appropriate.
*/
ret = 1;
}
goto no_kprobe;
}