Messages in this thread | | | Date | Mon, 12 Aug 2002 17:45:30 +1000 | From | Rusty Russell <> | Subject | Re: [patch 6/12] hold atomic kmaps across generic_file_read |
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On Fri, 9 Aug 2002 18:33:09 -0700 (PDT) Linus Torvalds <torvalds@transmeta.com> wrote:
> repeat: > kmap_atomic(..); // this increments preempt count > nr = copy_from_user(..);
Please please please use a different name for "I know I'm not preemptible but I can handle it" or a flag or something.
That leaves us with the possibility of a BUG() in the "normal" copy_to/from_user for all those "I'm holding a spinlock while copying to userspace wheeee!" bugs. Very common mistake for new kernel authors.
With the preempt count we have an easy way of detecting this at runtime: I'd like to keep that.
Rusty. -- there are those who do and those who hang on and you don't see too many doers quoting their contemporaries. -- Larry McVoy - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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