Re: [PATCH v2 09/16] PM / hibernate: Reserve hibernation key and erase footprints

joeyli
2015-08-13T14:34:22Z

On Tue, Aug 11, 2015 at 02:16:29PM +0800, Lee, Chun-Yi wrote:
> Add handler to parse the setup data that carrying hibernation key, it
> reserves hibernation key by memblock then copies key to a allocated page
> in later initcall stage.
>
[...snip]
> diff --git a/arch/x86/power/hibernate_keys.c b/arch/x86/power/hibernate_keys.c
> new file mode 100644
> index 0000000..357dc0e
> --- /dev/null
> +++ b/arch/x86/power/hibernate_keys.c
> @@ -0,0 +1,78 @@
> +/* Hibernation keys handler
> + *
[...snip]
> +static int __init init_hibernation_keys(void)
> +{
> + struct hibernation_keys *keys;
> + int ret = 0;
> +
> + if (!keys_phys_addr)
> + return -ENODEV;
> +
> + keys = early_memremap(keys_phys_addr, sizeof(struct hibernation_keys));
> +
> + /* Copy hibernation keys to a allocated page */
> + hibernation_keys = (struct hibernation_keys *)get_zeroed_page(GFP_KERNEL);
> + if (hibernation_keys) {
> + *hibernation_keys = *keys;
> + } else {
> + pr_err("PM: Allocate hibernation keys page failed\n");
> + ret = -ENOMEM;
> + }
> +
> + /* Erase keys data no matter copy success or failed */
> + memset(keys, 0, sizeof(struct hibernation_keys));
> + early_memunmap(keys, sizeof(struct hibernation_keys));
> + memblock_free(keys_phys_addr, sizeof(struct hibernation_keys));
> + keys_phys_addr = 0;
> +
> + return ret;
> +}
> +
> +late_initcall(init_hibernation_keys);

Yu's reviewing triggered me rethinking...

I afraid that's too late in late_initcall stage for copying key data that
reserved by memblock. I will try to move this copy action to setup_arch().

Regards
Joey Lee