I've been trying to get a Linux kernel to run that I've configured and compiled myself, but so far without success. The machine is an Apple Macbook (Intel Core 2 Duo, 64-bit) that has the free Libreboot firmware installed, with GRUB2 as a payload. I am trying to use this custom kernel to boot up a Linux From Scratch installation that I have built. I have Trisquel GNU/Linux (version 7) installed on another partition on the machine, which works fine, so I know it is possible to boot up GNU/Linux on this hardware/firmware configuration.
The kernel version is 4.13.1 (linux-libre) and it is the first time I've tried to compile my own kernel. When I try to boot it from the GRUB command prompt, the screen goes black and no output shows; however, it does write to the /var/log/kern.log file. In particular, I am puzzled by the following message at the start of the log file:
Oct 9 17:24:17 <lee_lfs> kernel: klogd 1.5.1, log source = /proc/kmsg started. Oct 9 17:24:17 <lee_lfs> kernel: Inspecting /boot/System.map Oct 9 17:24:17 <lee_lfs> kernel: Cannot find map file. Oct 9 17:24:17 <lee_lfs> kernel: Loaded 100800 symbols from 32 modules. Oct 9 17:24:17 <lee_lfs> kernel: [ 0.000000] random: get_random_bytes called from start_kernel+0x30/0x3bc with crng_init=0 Oct 9 17:24:17 <lee_lfs> kernel: [ 0.000000] Linux version 4.13.1-gnu (nobody@lee-LibreBook) (gcc version 7.2.0 (GCC)) #1 SMP PREEMPT Mon Oct 9 13:39:53 EDT 2017
The second line down there seems to indicate that it has found the /boot/System.map file; however, the following line suggests that the file is being rejected (which I suspect may be at least partly responsible for the failure of the kernel to fully boot up).
Does anyone have any idea of what might be causing this? I asked this question before on the Linux Questions site (link here); however, no-one there was able to figure it out. (That link contains some more background to the problem and things that have been suggested before).
Edit - to answer a suggestion that was made in the comments:
One user suggested that the 'Inspecting ...' line might not literally mean that klogd is accessing the file, but might just mean that it has started looking for it. However, I initially had forgotten to add a line in /etc/fstab for the /boot partition (in which case, it obviously wouldn't be able to find the file) and that 'Inspecting ...' line wasn't being printed. It was only after I fixed /etc/fstab that that line started to appear in the log, and with the correct path to the map file. This is why I suspect that klogd is finding the map file, but doesn't seem to be accepting it for some reason.