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An unexpected perf feature
LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
PostgreSQL 9.3 beta: Federated databases and more
LWN.net Weekly Edition for May 9, 2013
i think for most people (esp. kernel devs) modify = patch, and not 'reconfigure'. but for all i care, i got the point across :).
> but I was thinking that userspace had the added protection of segments to protect against accessing the kernel.
even if the default segments were set up this way, there's modify_ldt and TLS to get around them.
> Are you saying that since Linux uses a flat segment space that the bugs happen for both i386 and x86_64?
yes (if 'happen' = 'are exploitable'). UDEREF on i386 uses segmentation to prevent exactly this class of bugs from becoming exploitable beyond DoS.
Quotes of the week
Posted Jun 14, 2012 16:38 UTC (Thu) by nevets (subscriber, #11875)
Which goes back to my original point. Why run vanilla Linux i386 on x86_64. It's better to just run x86_64 kernel with a i386 userspace, then an i386 kernel if you have extended RAM.
Posted Jun 14, 2012 18:11 UTC (Thu) by PaXTeam (subscriber, #24616)
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