Dear Akemi, I'm really ashamed, in "https://wiki.centos.org/HowTos/I_need_the_Kernel_Source" I've missed the last 5 lines following the CentOS5 section. All is now clear for me on the process to follow to build a new kernel from source rpm and the CONFIG_NUMA_EMU option is active. I've set it with make menuconfig to avoid some additional mistakes in the config file. However, with this CONFIG_NUMA_EMU option , the compiler returns an error and compilation fails. arch/x86/mm/srat_64.c: In function 'acpi_fake_nodes': arch/x86/mm/srat_64.c:469: error: implicit declaration of function '__acpi_map_pxm_to_node' make[2]: *** [arch/x86/mm/srat_64.o] Error 1 make[1]: *** [arch/x86/mm] Error 2 make: *** [arch/x86] Error 2 make: *** Waiting for unfinished jobs.... error: Bad exit status from /var/tmp/rpm-tmp.VkJ805 (%build) Bad exit status from /var/tmp/rpm-tmp.VkJ805 (%build) Without CONFIG_NUMA_EMU option, compilation is successfull. It is the CentOSplus kernel from kernel-2.6.32-573.el6.centos.plus.src.rpm as yous suggested. Thank for your patience Patrick Akemi Yagi wrote: > On Tue, Mar 29, 2016 at 2:27 AM, Patrick Begou < > Patrick.Begou at legi.grenoble-inp.fr> wrote: > >> Akemi Yagi wrote: >> >>> I recommend you follows the instructions in this CentOS wiki article: >>> >>> https://wiki.centos.org/HowTos/Custom_Kernel >>> >>> If you encounter any issue, please let us know here. >>> >>> Akemi >>> >>> Thanks for answering Akemi . Indeed I tried using this howto before >> posting but something is wrong in this tutorial. >> >> I installed the prerequisites and downloaded the kernel sources as >> detailed in section 2 of >> https://wiki.centos.org/HowTos/I_need_the_Kernel_Source. >> >> But on https://wiki.centos.org/HowTos/Custom_Kernel, section 2, all goes >> wrong! >> My ~/rpmbuild/BUILD directory is empty! >> No configs directory too. >> No ~/rpmbuild/BUILD/kernel-*/linux-*/ available, all configs files are in >> ~/rpmbuild/SOURCES >> > The referenced wiki article should work for building CentOS-6 kernels (not > quite ready for CentOS-7). You really have to dot the i's and cross the > t's. If you miss a step or command in there, chances are it will fail. > > >> Since this I try to modify ~/rpmbuild/SOURCES/config-x86-generic because >> it was the only file containing the CONFIG_ACPI_NUMA flag. No success, the >> build does not take account of my changes as the >> ~/rpmbuild/BUILD/kernel-2.6.32-573.22.1.el6/linux-2.6.32-573.22.1.el6.numa.x86_64/.config >> created file with: >> rpmbuild -bb --without xen --without debug --without debuginfo >> --target=x86_64 ./SPECS/kernel.spec >> says "# CONFIG_NUMA_EMU is not set" >> >> So I change this file with an editor and rebuild the rpm package of the >> kernel with the same command. The .config file is overwriten. >> > As you found out, editing the existing config-x86-generic file would not > work because the final config file is created on the fly. This is why the > wiki instructions tell you to create your customized config file and show > you how to get that config file to be used during the build process. > > I have another suggestion for you. Get the srpm for the CentOSPlus kernel > instead of the distro kernel. The plus kernel is a customized kernel. It > has kernel-xx-config files that you can directly edit. They will not be > overwritten. Perhaps this method is easier. > > But if you wish to go for the original method, just be extremely precise > not to skip any step. > > Hope this helps, > > Akemi > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos > -- =================================================================== | Equipe M.O.S.T. | | | Patrick BEGOU | mailto:Patrick.Begou at grenoble-inp.fr | | LEGI | | | BP 53 X | Tel 04 76 82 51 35 | | 38041 GRENOBLE CEDEX | Fax 04 76 82 52 71 | ===================================================================