Re: [PATCH] strict VM overcommit for stock 2.4
From: Robert Love <hidden>
Date: 2002-07-18 17:39:48
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On Thu, 2002-07-18 at 09:36, Szakacsits Szabolcs wrote:
This is what I would do first [make sure you don't hit any resource,
malloc, kernel memory mapping, etc limits -- this is a simulation that
must eat all available memory continually]:
main(){void *x;while(1)if(x=malloc(4096))memset(x,666,4096);}
When the above used up all the memory try to ssh/login to the box as
root and clean up the mess. Can you do it?Three points: - with strict overcommit and the "allocations must meet backing store" rule (policy #3) the above can never use all physical memory - if your point is that a rogue user can use all of the systems memory, then you need per-user resource accounting. - the point of this patch is to not use MORE memory than the system has. I say nothing else except that I am trying to avoid OOM and push the allocation failures into the allocations themselves. Assuming the accounting is correct (and it seems to be) then Alan and I have succeeded. Robert Love -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/