swap_dup/swap_free: Bad swap file entry
What do these messages mean? That something is terribly hosed?
swap_dup: Bad swap file entry 1842b040
VM: killing process cc1swap_free: Bad swap file entry 1dab3064swap_free: Bad swap file entry 1842b040swap_free: Bad swap file entry 18429040swap_free: Bad swap file entry 31d7303cswap_free: Bad swap offset entry 31d71000
(This is from a UP 2.4.18 kernel with XFS 1.1 patches.)
Is this caused by a hardware defect (broken IDE interface, maybe; in our case VIA vt8233)?
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Florian Weimer [email protected] University of Stuttgart http://CERT.Uni-Stuttgart.DE/people/fw/ RUS-CERT +49-711-685-5973/fax +49-711-685-5898
Quoted 1 line · Florian Weimer
What do these messages mean? That something is terribly hosed?
I'm afraid so.
Quoted 7 lines
swap_dup: Bad swap file entry1842b040
VM: killing process cc1swap_free: Bad swap file entry1dab3064swap_free: Bad swap file entry1842b040swap_free: Bad swap file entry 18429040swap_free: Bad swap file entry31d7303cswap_free: Bad swap offset entry31d71000
They mean that junk (corruption) has been found in your pagetables
- and the swap dup/free code was the first to notice. Of course, it could sometimes mean that the swap allocation code has gone wrong, but from the numbers here (userspace pointers?) I'd guess not.
The worry is not so much the bad entries identified by these messages, as the possible entries not reported, which looked like present page table entries, and may have led to the wrong pages being freed (but if all the corruption was userspace pointers, good chance that they all looked more like even swap entries than odd page table entries:
I'm presuming x86).
Quoted 4 lines
(This is from a UP 2.4.18 kernel with XFS 1.1 patches.)
Is this caused by a hardware defect (broken IDE interface, maybe; in our case VIA vt8233)?
That I can't judge. I'd wonder about the XFS patches, but I've no good grounds for that suspicion.
It looks as if a page is being used for two purposes (one of as your pagetable) at the same time, but how that comes about I don't know - though once it starts happening, the freeing of wrong pages as above an multiply the effect. It's always worth giving memtest86 a go in such cases, but there's nothing here that particularly suggests bad memory as the culprit.
Hugh