Linus saw it coming
Posted Feb 12, 2008 18:55 UTC (Tue) by eSk
In reply to: Linus saw it coming
Parent article: vmsplice(): the making of a local root exploit
Except that vmsplice() does not fall under the category of "VM games" since it does not actually go about modifying the page tables of the applications. Also Linus was referring to the performance downsides of playing "VM games". Considering that splice() and vmsplice() were added purely for performance reasons it would have been quite hypocritical to add vmsplice() to improve performance (if vmsplice() actually did play "VM games", that is). I'm not familiar with his criticism of vmsplice() from the performance standpoint that you refer to.
It should also be noted that Linus was in this quote quite wrong in his contempt for FreeBSD developers. FreeBSD developers were (and are) very much aware of the issues at hand. That's why the zero-copy socket option was disabled by default.
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