<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> Hi Josh, <div class=""><br class=""> </div> <div class="">Thanks for the information. We have two options here:</div> <div class=""><br class=""> </div> <div class="">1) staying with 3.4 kernel, back port ftrace and wherever needed, using gcc 4.9 to compile the kernel and KLMs</div> <div class="">2) migrating the kernel to 3.10 or 3.14, which is using the gcc 4.9</div> <div class=""><br class=""> </div> <div class="">Wondering from your point of view, which option is more efficient and less hassle?</div> <div class=""><br class=""> <div class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div class="">Thanks</div> <div class="">Michael</div> <div class=""><br class=""> </div> </div> <br class="Apple-interchange-newline"> <br class="Apple-interchange-newline"> </div> <br class=""> <div> <blockquote type="cite" class=""> <div class="">On Jan 20, 2016, at 7:39 AM, Josh Poimboeuf <<a href="mailto:jpoimboe@redhat.com" class="">jpoimboe@redhat.com</a>> wrote:</div> <br class="Apple-interchange-newline"> <div class="">On Tue, Jan 19, 2016 at 04:15:10PM +0000, Michael Liu (zuwliu) wrote:<br class=""> <blockquote type="cite" class="">I joined the member and try to send it again.<br class=""> <br class=""> Hello Kpatch,<br class=""> <br class=""> I’m in a project which requires running kpatch on our 3.4 kernel, wondering how much effort is needed to do so?<br class=""> <br class=""> We currently using GCC 4.6.3, but I think we can move to GCC 4.8 if needed. However we cannot move our kernel to 3.9.<br class=""> <br class=""> In 3.4 kernel I saw there is already ftrace, although there is no CONFIG_DYNAMIC_FTRACE_WITH_REGS feature. Wondering whether CONFIG_DYNAMIC_FTRACE_WITH_REGS is the only feature missing on 3.4 to support kpatch? Are there other things we need to backport to run kpatch on 3.4 kernel?<br class=""> <br class=""> Thank you for your time!<br class=""> </blockquote> <br class=""> Hi Michael,<br class=""> <br class=""> CONFIG_DYNAMIC_FTRACE_WITH_REGS is the biggest required feature I know<br class=""> about that's missing on 3.4.<br class=""> <br class=""> Also, there are at least some minor kernel API differences that affect<br class=""> the kpatch core module, described here:<br class=""> <br class=""> <a href="https://github.com/dynup/kpatch/issues/257" class="">https://github.com/dynup/kpatch/issues/257</a><br class=""> <br class=""> GCC 4.6 may have issues:<br class=""> <br class=""> <a href="https://github.com/dynup/kpatch/issues/246#issuecomment-46615292" class="">https://github.com/dynup/kpatch/issues/246#issuecomment-46615292</a><br class=""> <br class=""> Those are just the problems I know about. You might run into other<br class=""> issues...<br class=""> <br class=""> -- <br class=""> Josh<br class=""> </div> </blockquote> </div> <br class=""> </div> </body> </html>