Re: [PATCH] [v4] PM / hibernate: Fix hibernation panic caused by inconsistent e820 map

[Pavel Machek <pavel@ucw.cz>]

> v3:
>  - Adjust the logic to exclude the end_pfn boundary in pfn_mapped
>    when invoking mark_valid_pages, because the end_pfn is not
>    a mapped page frame, we should not regard it as a valid page.
> 
>    Move the sanity check of valid pages to a early stage in resuming
>    process(moved to mark_unsafe_pages), in this way, we can avoid
>    unnecessarily accessing these invalid pages in later stage(yes,
>    move to the original position Joey once introduced in:
>    Commit 84c91b7ae07c ("PM / hibernate: avoid unsafe pages in e820
>    reserved regions")
> 
>    With v3 patch applied, I did 30 cycles on my problematic platform,
>    no panic triggered anymore(50% reproducible before patched, by
>    plugging/unplugging memory peripheral during hibernation), and it
>    just warns of invalid pages.

NAK. Turning panic into data corruption is a bad idea.

> +	if (!swsusp_page_is_valid(pfn_to_page(pfn))) {
> +		pr_err(
> +		"PM: Hibernation failed, address %#010llx to restored not valid!\n",
> +			(unsigned long long) pfn << PAGE_SHIFT);

...and still bad english.

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html