[PATCH v2] powerpc/config: powernv_defconfig updates

[Balbir Singh]

On Wed, Apr 11, 2018 at 7:12 PM, Nicholas Piggin <npiggin at gmail.com> wrote:
> For consideration:
>
> * Add IPv6 support built in + additional modules - Because it's 2018 maan.
> * Add DEFERRED_STRUCT_PAGE_INIT - Let's see what breaks.

We did not find any benefits with this on a P8 in terms of boot time
with large memory. May be worth reinvestigating

> * Add PPC_MEMTRACE - Small powernv debugfs driver for getting hardware traces.
> * Add MEMORY_FAILURE - Machine check exceptions can now drive memory failure.
> * Turn on FANOTIFY - This is the current filesystem notification feature.
> * Turn on SCOM_DEBUGFS - Handy for hardware/firmware debugging, security risk?

Yep, should not be in defconfig, IMHO

> * Turn on async SCSI scanning - Let's see what breaks.
>
> * Make a bunch of USB hid drivers modules.
> * Make SCSI SG, SR, and FC modules - FC is huge.
> * Make video drivers (except AST GPU) modules - Also huge.
> * Add MLX5 driver as a module - Popular demand.
> * Make PCI serial driver a module - Uncommon?
>
> * Get rid of /dev/port - Not used.
> * Remove legacy BSD ttys - Long dead.
> * Remove IDE - Deprecated and replaced with ATA.
> * Remove WIRELESS - Until we get POWER9 laptops.
> * Remove RAW - Long deprecated in favour of direct IO.
> * Remove floppy, parport, and PS2 input devices - not supported.
> * Remove virtio drivers, ballooning - We're host only.

I still think its good to have them, may be as modules? Should I
switch to powerpc64le_defconfig for a single config with everything --
same kernel as guest and bare metal?

> * Remove PPP - Sorry Paulus.
> * Make more things modules, NFS FS, RAM disk, netconsole, MS-DOS fs.
>
> This does not disable FTRACE options, that's just an optimisation the
> defconfig target made. make powernv_defconfig adds those to .config.
>
> This results in a significantly smaller vmlinux:
>
>    text    data     bss     dec     hex filename
> 13121779        5284224 1383776 19789779        12df7d3 vmlinux
> 12126273        4771930 1341464 18239667        11650b3 vmlinux
>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---

Balbir Singh.