Merge "[REFACTOR] Buffer: move getting next queue element into separate function"

[kernel/swap-modules.git] / uprobe / arch / asm-x86 / swap_uprobes.c

diff --git a/uprobe/arch/asm-x86/swap_uprobes.c b/uprobe/arch/asm-x86/swap_uprobes.c
index 2b9635b..2ec59ac 100644 (file)
--- a/uprobe/arch/asm-x86/swap_uprobes.c
+++ b/uprobe/arch/asm-x86/swap_uprobes.c
@@ -75,10 +75,16 @@ int arch_prepare_uprobe(struct uprobe *up)
        struct kprobe *p = up2kp(up);
        struct task_struct *task = up->task;
        u8 *tramp = up->atramp.tramp;
+       enum { call_relative_opcode = 0xe8 };
 
        if (!read_proc_vm_atomic(task, (unsigned long)p->addr,
                                 tramp, MAX_INSN_SIZE))
                panic("failed to read memory %p!\n", p->addr);
+       /* TODO: this is a workaround */
+       if (tramp[0] == call_relative_opcode) {
+               printk("cannot install probe: 1st instruction is call\n");
+               return -1;
+       }
 
        tramp[UPROBES_TRAMP_RET_BREAK_IDX] = BREAKPOINT_INSTRUCTION;
 
@@ -369,7 +375,7 @@ static int uprobe_exceptions_notify(struct notifier_block *self, unsigned long v
        struct die_args *args = (struct die_args *)data;
        int ret = NOTIFY_DONE;
 
-       if (args->regs && !user_mode_vm(args->regs))
+       if (args->regs == NULL || !user_mode_vm(args->regs))
                return ret;
 
        switch (val) {