Re: [Patch v5] kdumpctl: adjust the boot dir if kernel is put in sub dir of /boot

[Vivek Goyal]

On Thu, Jan 29, 2015 at 06:09:11PM +0800, Baoquan He wrote:

[..]
>  +check_boot_dir()
>  +{
>  +	local _boot_dir
>  +	#If user specify a boot dir for kdump kernel, let's use it. Otherwise
>  +	#assume it's in the same place as 1st kernel.
>  +	#The BOOT_IMAGE is number like 0,1,.. , for now not handle it.
>  +	[ -n "$KDUMP_BOOTDIR" ] && return
>  +	[ "$(uname -m)" = "s390x" ] && return
>  +	_boot_dir=$(cat /proc/cmdline | grep "BOOT_IMAGE")
>  +	if [ -z "$_boot_dir" ]; then
>  +		KDUMP_BOOTDIR="/boot"
>  +	else
>  +		eval $(echo "$_boot_dir" | cut -d' ' -f1)
>  +		KDUMP_BOOTDIR="/boot"$(dirname $BOOT_IMAGE)
>  +	fi 
I think a better way to code this is following.

if user_specified_boot;
   use_it; return;
else if is_it_atomic_system;
   look for boot_image on /proc/cmdline; return
else
  use /boot
fi

That way you don't have to hardcode things for s390. And behavior will
remain unchanged for systems which are not atomic.

And you can grep for ostree= on /proc/cmdline to figure out if you are
booting on atomic system or not.

Thanks
Vivek