Re: kernel BUG at page_alloc.c:92! & page allocation failure. order:0,

[Andrew Morton]

Andrea Arcangeli wrote:
> 
> On Tue, Jul 23, 2002 at 12:24:04PM -0700, Andrew Morton wrote:
> > David F Barrera wrote:
> > >
> > > I have experienced the following errors while running a test suite (LTP
> > > test suite)  on the 2.4.26 kernel.  Has anybody seen this problem, and, if
> > > so, is there a patch for it?  Thanks.
> > >
> > > kernel BUG at page_alloc.c:92!
> >
> > Could you please replace the put_page(page) in
> > kernel/ptrace.c:access_process_vm() with page_cache_release(page)
> > and retest?
> 
> I prefer to drop page_cache_release and to have __free_pages_ok to deal
> with the lru pages like it's been fixed in 2.4.

That would fix it too.  But a __free_pages_ok call from interrupt
context can deadlock the box.

The removal of pages from the LRU is rather a mess.  It's getting
better, and we can fix up some more of this if/when pagemap_lru_lock
becomes an interrupt-safe lock.

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