Re: [RFC PATCH linux dev-5.4 3/4] ARM: configs: aspeed-g5: Enable kprobes

[Andrew Jeffery]

On Thu, 14 May 2020, at 22:57, Andrew Jeffery wrote:
> Enable kprobes to improve the debugging experience on the AST2500 and
> later.
> 
> Setting CONFIG_KPROBES=y results in the following change in kernel size:
> 
> Before:
>          $ size vmlinux
>             text    data     bss     dec     hex filename
>          8240349 2388862  172304 10801515         a4d16b vmlinux
>          $ stat --printf '%s\n' *.zImage
>          3458368
> 
> After:
>          $ size vmlinux
>             text    data     bss     dec     hex filename
>          8279214 2399530  176912 10855656         a5a4e8 vmlinux
>          $ stat --printf '%s\n' *.zImage
>          3471880
> 
> This gives a 54,141 byte increase to vmlinux and a 13,512 byte increase
> to the size of the compressed kernel image. In the most constrained BMC
> flash layout (arch/arm/boot/dts/openbmc-flash-layout.dtsi) this change
> decreases the free space in the kernel partition from 998,080 bytes to
> 984,568 bytes.

Just realised I should be measuring the FIT not the zImage so ignore the
free-space numbers for the moment.

Andrew