Ubuntu – Kernel doesn’t support PIC mode for compiling

compilinggcckernel

I've been trying to compile the latest Linux v4.8.9 kernel on Ubuntu 16.10 and this error keeps popping up after I've made the default .config, modified it with menuconfig and ran make by itself. I've also run make mrproper as soon as I untarred the file. This is the output right after I run make:

scripts/kconfig/conf  --silentoldconfig Kconfig
  SYSTBL  arch/x86/entry/syscalls/../../include/generated/asm/syscalls_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/asm/unistd_32_ia32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/asm/unistd_64_x32.h
  SYSTBL  arch/x86/entry/syscalls/../../include/generated/asm/syscalls_64.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_64.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_x32.h
  HOSTCC  arch/x86/tools/relocs_32.o
  HOSTCC  arch/x86/tools/relocs_64.o
  HOSTCC  arch/x86/tools/relocs_common.o
  HOSTLD  arch/x86/tools/relocs
  CHK     include/config/kernel.release
  UPD     include/config/kernel.release
  WRAP    arch/x86/include/generated/asm/clkdev.h
  WRAP    arch/x86/include/generated/asm/cputime.h
  WRAP    arch/x86/include/generated/asm/dma-contiguous.h
  WRAP    arch/x86/include/generated/asm/early_ioremap.h
  WRAP    arch/x86/include/generated/asm/mcs_spinlock.h
  WRAP    arch/x86/include/generated/asm/mm-arch-hooks.h
  CHK     include/generated/uapi/linux/version.h
  UPD     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  UPD     include/generated/utsrelease.h
  CC      kernel/bounds.s
kernel/bounds.c:1:0: error: code model kernel does not support PIC mode
 /*

Kbuild:45: recipe for target 'kernel/bounds.s' failed
make[1]: *** [kernel/bounds.s] Error 1
Makefile:1015: recipe for target 'prepare0' failed
make: *** [prepare0] Error 2

I've also tried compiling with the -no-pie option after the make command but it renders a set of new errors, constantly saying that there are "missing targets". I have gcc version 6.2.0. I also have gcc-5 installed because I assumed in the beginning it might be because gcc was too new but the same problem persists in gcc-5. Someone in the mailing lists or another forum mentioned that the problem was resolved by directly cloning from git but that didn't help in my scenario either.

I'm curious if anyone else has run into this problem and if so, what a possible fix might be?

NOTE:I'm running Ubuntu in Virtualbox on a Mac if that might be a possible source of problems.

Best Answer

The issue is with your gcc installation, in gcc 6+ versions PIE( position independent executables) is enabled by default. So in order to compile you need to disable it. Even gcc 5 has the issue. This is a known bug for gcc. Bug Link.

So far there is no official patch from gcc side, so the workaround is to patch the Makefile of kernel source.

If you are familiar with patching the source file use the codes from this link to create the patch file then try to compile.Patch File

Let me know if you are having difficulties installing the patch.

Setup once

$ cd ~
$ apt-get source linux-source-3.13.0

I am too lazy to copy the mvsas specific driver source files; just copy them all to your current working directory. If apt-get results in an error message about missing source URIs then see note #4 at the bottom.

$ cd linux-3.13.0
$ make oldconfig
$ make prepare
$ make scripts

This will prepare some files necessary to build a kernel module.

Each kernel version

$ apt-get install linux-headers-$(uname -r)

This will install headers and the Ubuntu kernel configuration file for that kernel version in /lib/modules.

$ cd ~/linux-3.13.0
$ cp -v /usr/src/linux-headers-$(uname -r)/Module.symvers .

This to prevent the message "no symbol version for module_layout" when loading the module with insmod or modprobe.

$ mv -v /lib/modules/$(uname -r)/kernel/drivers/scsi/mvsas/mvsas.ko /lib/modules/$(uname -r)/kernel/drivers/scsi/mvsas/mvsas.ko.backup

This will rename the original (Ubuntu build) kernel module to make sure that the custom patched one will load.

Each edit

$ cd ~/linux-3.13.0/drivers/scsi/mvsas
$ nano mv_sas.h
$ nano mv_sas.c

These are for the edits.

$ make -C /lib/modules/$(uname -r)/build M=$(pwd) modules

This will compile and build the kernel module .ko file using the kernel configuration from your stock Ubuntu distribution as stored in /lib/modules/$(uname -r)/.

$ make -C /lib/modules/$(uname -r)/build M=$(pwd) modules_install

This will install the kernel module in /lib/modules/$(uname -r)/extra/, not overwriting the distribution module in case you didn't rename the distribution kernel module file. In this mvsas case it will also run depmod.

$ lsmod | grep mvsas

If this results in any output, the mvsas module needs unloading with (modprobe -r mvsas) first.

$ sudo modprobe -v mvsas

This should load the new kernel module.

Check the output to verify that /lib/modules/.../extra/mvsas.ko is being loaded.

Modprobe error: could not insert

In some cases you might experience a modprobe: ERROR: could not insert 'xyz': Unknown symbol in module, or unknown parameter (see dmesg) while in the verbose modprobe output you see that insmod is trying to load the module from the kernel default location. For example:

# insmod /lib/modules/3.17.0-031700rc7-generic/kernel/drivers/scsi/pm8001/pm80xx.ko
modprobe: ERROR: could not insert 'pm80xx': Unknown symbol in module, or unknown parameter (see dmesg)

In that case you need to manually run depmod and try to load the module again:

# depmod
# sudo modprobe -v mvsas

Notes

It may be the case that the resulting .ko module files are much (for example 20 times) larger in size than the original module files as distributed by Ubuntu; in that case the make prepare step could have created a Linux developers debugging kernel configuration file and you are building from the source directory. Your -C param might not function as expected.
I have seen guides with other commands like make modules_prepare and make M=scripts/mod but I don't think these are necessary for this case.
You can use the Linux developers debug config by replacing -C /lib/modules/$(uname -r)/build with -C /usr/src/linux-headers-$(uname -r)
In a default setup, apt-get source linux-sources will return error E: You must put some 'source' URIs in your sources.list. To fix this issue you can modify file /etc/apt/sources.list by uncommenting (removing the leading # from) the first deb-src line. Example for Ubuntu 17.10: deb-src http://ie.archive.ubuntu.com/ubuntu/ artful main restricted. run sudo apt-get update, and then the command will deliver sources for you. See also this question where a GUI method for doing this is described too.

Ubuntu – Linux/autoconf.h not present

linux/autoconf.h has moved to generated/autoconf.h it seems in newer kernels. I don't know when this happened, but I had the same problem with a 3.2 kernel. I just renamed and this seemed to fix that specific problem. However there will probably be other changes so I suspect you will still need to port the driver to your required kernel.