Messages in this thread | | | Date | Wed, 23 Nov 2011 14:25:56 +0100 | From | Stanislaw Gruszka <> | Subject | Re: [PATCH v2 1/3] mm: more intensive memory corruption debug |
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On Tue, Nov 22, 2011 at 01:56:08PM -0800, Andrew Morton wrote: > On Fri, 18 Nov 2011 17:25:05 +0100 > Stanislaw Gruszka <sgruszka@redhat.com> wrote: > I added this: > > The default value of debug_guardpage_minorder is zero: no change > from current behaviour. > > correct? Yes,
> > +static inline void clear_page_guard_flg(struct page *page) > > +{ > > + __clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); > > +} > > Why is it safe to use the non-atomic bitops here. Clearing/setting flag is done only in __free_one_page()/expand(), so operations are protected by zone->lock.
> Please verify that CONFIG_WANT_PAGE_DEBUG_FLAGS is always reliably > enabled when this feature is turned on. Change in mm/Kconfig.debug assures that CONFIG_WANT_PAGE_DEBUG_FLAGS is set whenever CONFIG_DEBUG_PAGEALLOC is.
> Some changes I made - please review. Look good, thanks Andrew!
Stanislaw
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