Re: Ideas for v2.1

Alan Cox (alan@cymru.net)
Tue, 11 Jun 1996 14:10:52 +0100 (BST)


> for a request of, say, 2k (as something previosuly lied that the
> block being freeing was 2k...). This would corrupt the allocator even
> more, leading to a panic in a _totally_ unrelated area.

Im used to this with the net code and current stuff. Thats why I use the
magic numbers.

> I'm not fond of the idea that a central kernel service doesn't
> validate itself.

Scribbling a magic number in the first long word of a free block wouldnt be
too bad a hit for basic sanity checks. Since you can get memory tramples
from stuff like stale TLB entries that are far harder to find Im less
concerned.

The TLB one is likely to be even nastier as people go to stuff like DMA
to/from user space and do things like creating windows for interrupts to
occur between the set_pte() and the mmu reload or tlb flush.

Werner - I don't think you handle this yet for the ATM code do you ?

Alan