Messages in this thread |  | | Date | Thu, 11 Jan 2001 19:47:53 +0000 | From | "Stephen C. Tweedie" <> | Subject | Re: Subtle MM bug |
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Hi,
On Thu, Jan 11, 2001 at 02:03:48PM -0500, Alexander Viro wrote: > On Thu, 11 Jan 2001, Stephen C. Tweedie wrote: > > > On Thu, Jan 11, 2001 at 02:12:05PM +0100, Trond Myklebust wrote: > > > > > > What's wrong with copy-on-write style semantics? IOW, anyone who > > > wants to change the credentials needs to make a private copy of the > > > existing structure first. > > > > Because COW only solves the problem if each task is only changing its > > own, local, private copy of the credentials. Posix threads demand > > that one thread changing credentials also affects all the other > > threads immediately, and making your own local private copy won't help > > you to change the other tasks' credentials safely. > > And how is that different from the current situation?
It's not, which is the point I was making: COW doesn't actually solve the pthreads problem. Far better to do it in user space.
--Stephen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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