On Friday 09 January 2015 11:29 PM, Oleg Nesterov wrote:
On 12/31, Pratyush Anand wrote:+int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, + unsigned long addr) +{ + probe_opcode_t insn; + + insn = *(probe_opcode_t *)(&auprobe->insn[0]); + + switch (arm_probe_decode_insn(insn, &auprobe->ainsn)) { + case INSN_REJECTED: + return -EINVAL; + + case INSN_GOOD_NO_SLOT: + auprobe->simulate = true; + if (auprobe->ainsn.prepare) + auprobe->ainsn.prepare(insn, &auprobe->ainsn); + break; + + case INSN_GOOD: + default: + break; + } + + return 0; +}forgot to mention... shouldn't it also check IS_ALIGNED(addr, AARCH64_INSN_SIZE) ? I do not know if unaligned insn address is valid on arm64 or not, but please
AARCH64 instructions are always of fixed lenght ie 4 bytes. I do not see possibility of addr being unaligned. Please let me know, if I am missing something.
note that at least it should not cross the page boundary, set_swbp() needs to write AARCH64_INSN_SIZE == UPROBE_SWBP_INSN bytes and it assumes that this should fit the single page.
So, again I do not see the possibility of crossing of page boundary for any instruction address.
~Pratyush -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
