Messages in this thread | | | Date | Mon, 6 Aug 2012 16:24:18 -0300 | From | Rafael Aquini <> | Subject | Re: [PATCH v5 1/3] mm: introduce compaction and migration for virtio ballooned pages |
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On Mon, Aug 06, 2012 at 03:06:49PM -0400, Rik van Riel wrote: > > Just a plain rename would work. > Ok, I will rename it.
> >+static inline bool is_balloon_page(struct page *page) > >+{ > >+ return (page->mapping && page->mapping == balloon_mapping); > >+} > > As an aside, since you are only comparing page->mapping and > not dereferencing it, it can be simplified to just: > > return (page->mapping == balloon_mapping); > We really need both comparisons to avoid potential NULL pointer dereferences at __isolate_balloon_page() & __putback_balloon_page() while running at bare metal with no balloon driver loaded, since balloon_mapping itself is a pointer which each balloon driver can set to its own structure.
Thanks, Rik, for taking the time to look at this patch and provide (always) valuable feedback.
I'll shortly respin a v6 with your suggestions.
-- Rafael
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