Messages in this thread | | | Date | Mon, 17 Nov 2008 16:00:03 +1100 | From | Paul Mackerras <> | Subject | Re: [PATCH 5/7] ftrace, PPC64: handle module trampolines for dyn ftrace |
| |
Steven Rostedt writes:
> + if (!rec->arch.mod) { > + if (!mod) { > + printk(KERN_ERR "No module loaded addr=%lx\n", > + addr); > + return -EFAULT; > + } > + rec->arch.mod = mod; > + } else if (mod) { > + printk(KERN_ERR > + "Record mod %p not equal to passed in mod %p\n", > + rec->arch.mod, mod); > + return -EINVAL;
That looks wrong; surely you need an if (mod != rec->arch.mod) somewhere here?
> + /* Make sure that that this is still a 24bit jump */ > + if ((*op & 0xff000000) != 0x48000000) { > + printk(KERN_ERR "Not expected bl: opcode is %x\n", *op); > + return -EINVAL; > + }
Needs to be
if ((*op & 0xfc000003) != 0x48000001)
since the major opcode is the top 6 bits, and the bottom 2 bits are the link bit and the absolute address bit.
> + /* lets find where the pointer goes */ > + offset = (*op & 0x03fffffc); > + /* make it signed */ > + if (offset & 0x02000000) > + offset |= 0xfe000000;
but you got that right... :)
> + /* get the address this jumps too */ > + tramp = mod->arch.toc + offset + 32;
Why + 32?
Paul.
| |