Re: [PATCH 7/8] initramfs: proide a generic free_initrd_mem implementation

From: Mike Rapoport
Date: Wed Feb 13 2019 - 13:54:29 EST


On Wed, Feb 13, 2019 at 06:46:20PM +0100, Christoph Hellwig wrote:
> For most architectures free_initrd_mem just expands to the same
> free_reserved_area call. Provide that as a generic implementation
> marked __weak.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> arch/alpha/mm/init.c | 8 --------
> arch/arc/mm/init.c | 7 -------
> arch/c6x/mm/init.c | 7 -------

csky seems to open-code free_reserved_page with the only
difference that it's also increments totalram_pages for the freed pages,
which doesn't seem correct anyway...

That said, I suppose arch/csky can be also added to the party.

> arch/h8300/mm/init.c | 8 --------
> arch/m68k/mm/init.c | 7 -------
> arch/microblaze/mm/init.c | 7 -------
> arch/nds32/mm/init.c | 7 -------
> arch/nios2/mm/init.c | 7 -------
> arch/openrisc/mm/init.c | 7 -------
> arch/parisc/mm/init.c | 7 -------
> arch/powerpc/mm/mem.c | 7 -------
> arch/sh/mm/init.c | 7 -------
> arch/um/kernel/mem.c | 7 -------
> arch/unicore32/mm/init.c | 7 -------
> init/initramfs.c | 5 +++++
> 15 files changed, 5 insertions(+), 100 deletions(-)

...

> diff --git a/init/initramfs.c b/init/initramfs.c
> index cf8bf014873f..f3aaa58ac63d 100644
> --- a/init/initramfs.c
> +++ b/init/initramfs.c
> @@ -527,6 +527,11 @@ extern unsigned long __initramfs_size;
> #include <linux/initrd.h>
> #include <linux/kexec.h>
>
> +void __weak free_initrd_mem(unsigned long start, unsigned long end)
> +{
> + free_reserved_area((void *)start, (void *)end, -1, "initrd");

Some architectures have pr_info("Freeing initrd memory..."), I'd add it for
the generic version as well.

Another thing that I was thinking of is that x86 has all those memory
protection calls in its free_initrd_mem, maybe it'd make sense to have them
in the generic version as well?

> +}
> +
> #ifdef CONFIG_KEXEC_CORE
> static bool kexec_free_initrd(void)
> {
> --
> 2.20.1
>

--
Sincerely yours,
Mike.