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Diffstat (limited to 'arch/ia64/kernel/kprobes.c')
-rw-r--r--arch/ia64/kernel/kprobes.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 82a41ac2938..4b1bd539ec4 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -554,6 +554,38 @@ static void __kprobes prepare_ss(struct kprobe *p, struct pt_regs *regs)
ia64_psr(regs)->ss = 1;
}
+static int __kprobes is_ia64_break_inst(struct pt_regs *regs)
+{
+ unsigned int slot = ia64_psr(regs)->ri;
+ unsigned int template, major_opcode;
+ unsigned long kprobe_inst;
+ unsigned long *kprobe_addr = (unsigned long *)regs->cr_iip;
+ bundle_t bundle;
+
+ memcpy(&bundle, kprobe_addr, sizeof(bundle_t));
+ template = bundle.quad0.template;
+
+ /* Move to slot 2, if bundle is MLX type and kprobe slot is 1 */
+ if (slot == 1 && bundle_encoding[template][1] == L)
+ slot++;
+
+ /* Get Kprobe probe instruction at given slot*/
+ get_kprobe_inst(&bundle, slot, &kprobe_inst, &major_opcode);
+
+ /* For break instruction,
+ * Bits 37:40 Major opcode to be zero
+ * Bits 27:32 X6 to be zero
+ * Bits 32:35 X3 to be zero
+ */
+ if (major_opcode || ((kprobe_inst >> 27) & 0x1FF) ) {
+ /* Not a break instruction */
+ return 0;
+ }
+
+ /* Is a break instruction */
+ return 1;
+}
+
static int __kprobes pre_kprobes_handler(struct die_args *args)
{
struct kprobe *p;
@@ -601,6 +633,19 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
p = get_kprobe(addr);
if (!p) {
unlock_kprobes();
+ if (!is_ia64_break_inst(regs)) {
+ /*
+ * 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;
+
+ }
+
+ /* Not one of our break, let kernel handle it */
goto no_kprobe;
}