Question with make menuconfig

[aprideangel]

Hi,

I installed RHEL 6.2, then downloaded the 3.2.1 kernel source from kernel.org and unpacked it to /tmp/linux-3.2.1.

From /tmp/linux-3.2.1 directory, I issued the following commands to build and install this kernel:
- make mrproper
- make menuconfig => did not make any changes, just saved it
- make bzImage
- make modules
- make modules_install
- make install

After booting up with the 3.2.1 kernel, I went to /tmp/linux-3.21 directory and saved .config to .config_3.2.1. I then issued:
-make mrproper
-make menuconfig => did not make any changes, just saved it

When I compared .config with .config_3.2.1, I see differences. Does anyone know why?

Thanks for any help, greatly appreciate it!

[atreyu]

well, what are the differences? is there a timestamp in there? post the output of:

diff .config .config_3.2.1

if you want.

[Rubberman]

The difference is probably the time stamp, and possibly the kernel version. Here is an example of the .config header from one kernel that I have configured and built.

#
# Automatically generated make config: don't edit
# Linux kernel version: 2.6.32-131.17.1.el6.x86_64
# Wed Oct 5 17:17:39 2011
#

[aprideangel]

Thanks for the initial inputs. The differences are quite big. Here's a snippet of the sdiff -s output (27 lines out of 3198 lines):

                                                              > CONFIG_GENERIC_GPIO=y
CONFIG_HAVE_INTEL_TXT=y                                       <
# CONFIG_BSD_PROCESS_ACCT_V3 is not set                       | CONFIG_BSD_PROCESS_ACCT_V3=y
CONFIG_LOG_BUF_SHIFT=18                                       | CONFIG_LOG_BUF_SHIFT=19
# CONFIG_CGROUP_DEVICE is not set                             | CONFIG_CGROUP_DEVICE=y
# CONFIG_CGROUP_MEM_RES_CTLR is not set                       | CONFIG_CGROUP_MEM_RES_CTLR=y
# CONFIG_CGROUP_PERF is not set                               | CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y
                                                              > CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED=y
                                                              > CONFIG_CGROUP_PERF=y
# CONFIG_CFS_BANDWIDTH is not set                             | CONFIG_CFS_BANDWIDTH=y
# CONFIG_RT_GROUP_SCHED is not set                            | CONFIG_RT_GROUP_SCHED=y
# CONFIG_BLK_CGROUP is not set                                | CONFIG_BLK_CGROUP=y
                                                              > # CONFIG_DEBUG_BLK_CGROUP is not set
# CONFIG_SCHED_AUTOGROUP is not set                           | CONFIG_SCHED_AUTOGROUP=y
                                                              > CONFIG_MM_OWNER=y
# CONFIG_KALLSYMS_ALL is not set                              | CONFIG_KALLSYMS_ALL=y
# CONFIG_PERF_COUNTERS is not set                             | CONFIG_PERF_COUNTERS=y
CONFIG_SLUB_DEBUG=y                                           <
# CONFIG_SLAB is not set                                      | CONFIG_SLAB=y
CONFIG_SLUB=y                                                 | # CONFIG_SLUB is not set
# CONFIG_OPROFILE is not set                                  | CONFIG_OPROFILE=m
                                                              > CONFIG_OPROFILE_EVENT_MULTIPLEX=y
                                                              > CONFIG_USER_RETURN_NOTIFIER=y
# CONFIG_MODULE_FORCE_LOAD is not set                         | CONFIG_MODULE_FORCE_LOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y                                  | # CONFIG_MODULE_FORCE_UNLOAD is not set
# CONFIG_MODVERSIONS is not set                               | CONFIG_MODVERSIONS=y
# CONFIG_MODULE_SRCVERSION_ALL is not set                     | CONFIG_MODULE_SRCVERSION_ALL=y
... ...

or simply snippet of the diff output:

28a29
> CONFIG_GENERIC_GPIO=y
48d48
< CONFIG_HAVE_INTEL_TXT=y
83c83
< # CONFIG_BSD_PROCESS_ACCT_V3 is not set
---
> CONFIG_BSD_PROCESS_ACCT_V3=y
117c117
< CONFIG_LOG_BUF_SHIFT=18
---
> CONFIG_LOG_BUF_SHIFT=19
122c122
< # CONFIG_CGROUP_DEVICE is not set
---
> CONFIG_CGROUP_DEVICE=y
127,128c127,130
< # CONFIG_CGROUP_MEM_RES_CTLR is not set
< # CONFIG_CGROUP_PERF is not set
---
> CONFIG_CGROUP_MEM_RES_CTLR=y
> CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y
> CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED=y
> CONFIG_CGROUP_PERF=y
131,133c133,136
< # CONFIG_CFS_BANDWIDTH is not set
< # CONFIG_RT_GROUP_SCHED is not set
... ...