On Thu, Sep 10, 2009 at 10:50:47PM -0400, Siarhei Liakh wrote: > This patch is a logical extension of the protection provided by > CONFIG_DEBUG_RODATA to LKMs. The protection is provided by splitting > module_core and module_init into three logical parts each and setting > appropriate page access permissions for each individual section: > > 1. Code: RO+X > 2. RO data: RO+NX > 3. RW data: RW+NX Hi Siarhei, I tried out this patch on 2.6.31, and got the following trace during bootup.. ------------[ cut here ]------------ WARNING: at kernel/trace/ftrace.c:1003 ftrace_bug+0x198/0x27e() (Not tainted) Hardware name: VGN-Z540N Modules linked in: output(+) Pid: 115, comm: modprobe Not tainted 2.6.31-23.fc12.x86_64 #1 Call Trace: [<ffffffff81064244>] warn_slowpath_common+0x95/0xc3 [<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output] [<ffffffff81064299>] warn_slowpath_null+0x27/0x3d [<ffffffff810d4a0e>] ftrace_bug+0x198/0x27e [<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output] [<ffffffff810d5c66>] ftrace_convert_nops+0x201/0x2b9 [<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output] [<ffffffff810d5d6a>] ftrace_module_notify+0x4c/0x7f [<ffffffff815099c5>] notifier_call_chain+0x72/0xba [<ffffffff81086db1>] ? __blocking_notifier_call_chain+0x4c/0x8e [<ffffffff81086dc8>] __blocking_notifier_call_chain+0x63/0x8e [<ffffffff81086e1a>] blocking_notifier_call_chain+0x27/0x3d [<ffffffff810a466a>] sys_init_module+0xb7/0x249 [<ffffffff81011f42>] system_call_fastpath+0x16/0x1b ---[ end trace 95b33ebf87286ae6 ]--- ftrace faulted on writing [<ffffffffa0000193>] video_output_register+0x11/0x10a [output] I guess ftrace is trying to NOP out something in the modules which are marked read-only ? Dave -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
