Currently we always execute all insns out-of-line, including relative jmp's and call's. This assumes that even if regs->ip points to nowhere after the single-step, default_post_xol_op(UPROBE_FIX_IP) logic will update it correctly. However, this doesn't work if this regs->ip == xol_vaddr + insn_offset is not canonical. In this case CPU generates #GP and general_protection() kills the task which tries to execute this insn out-of-line. Now that we have uprobe_xol_ops we can teach uprobes to emulate these insns and solve the problem. This patch adds branch_xol_ops which has a single branch_emulate_op() hook, so far it can only handle rel8/32 relative jmp's. TODO: move ->fixup into the union along with rip_rela_target_address. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Jonathan Lebon <jlebon@redhat.com> Reviewed-by: Jim Keniston <jkenisto@us.ibm.com> |
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| .. | ||
| boot | ||
| configs | ||
| crypto | ||
| ia32 | ||
| include | ||
| kernel | ||
| kvm | ||
| lguest | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| pci | ||
| platform | ||
| power | ||
| realmode | ||
| syscalls | ||
| tools | ||
| um | ||
| vdso | ||
| video | ||
| xen | ||
| .gitignore | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.cpu | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile.um | ||
| Makefile_32.cpu | ||