Re: page_alloc bug in 2.4.17-pre8

[Hugh Dickins]

On Thu, 23 May 2002, Mike Black wrote:
> This machine had been up for 2-1/2 days and had run this backup (afio) twice successfully.
> 
> Here's line 108 of page_alloc.c:
>         if (PageLRU(page))
>                 BUG();
> 
> Hopefully this doesn't indicate a CPU problem?  The power supply on this thing blew Saturday but has run OK until now.
> 
> May 22 00:51:01 picard kernel: kernel BUG at page_alloc.c:108!
> May 22 00:51:01 picard kernel: invalid operand: 0000
> May 22 00:51:01 picard kernel: CPU:    1
> May 22 00:51:01 picard kernel: EIP:    0010:[swap_duplicate+82/192]    Not tainted

There were quite a number of reports of those PageLRU BUGs on 2.4.17.
No idea what fixed them, but 2.4.18 (and 2.4.19-pre) has seemed free
of them (Ben LaHaise made a plausible change, but closer analysis
suggested it couldn't really be the fix).  Suggest you upgrade.

Your oops report, by the way, must have been using the wrong System.map:
page_alloc.c:108 is in __free_pages_ok(), swap_duplicate() is over in
swapfile.c.  But no matter, page_alloc.c:108 identifies it well enough.

Hugh