On Thu, 1 Nov 2012 15:03:00 -0400 Nick Bowler <[email protected]> wrote:
> There is absolutely no reason to crash the kernel when we have a > perfectly good return value already available to use for conveying > failure status. Yes, I suppose that's true. I don't see a case for BUGging the kernel here. > Let's return an error code instead of crashing the kernel: that sounds > like a much better plan. > > Signed-off-by: Nick Bowler <[email protected]> > --- > lib/scatterlist.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/lib/scatterlist.c b/lib/scatterlist.c > index 3675452b23ca..11ecaf000696 100644 > --- a/lib/scatterlist.c > +++ b/lib/scatterlist.c > @@ -248,7 +248,8 @@ int __sg_alloc_table(struct sg_table *table, unsigned int > nents, > unsigned int left; > > #ifndef ARCH_HAS_SG_CHAIN > - BUG_ON(nents > max_ents); > + if (WARN_ON_ONCE(nents > max_ents)) > + return -E2BIG; > #endif OK, pet peeve: if this E2BIG gets returned to userspace, our poor user will look it up and see "Argument list too long; used when the arguments passed to a new program being executed with one of the exec functions occupy too much memory space". He then gets to spend half a day reviewing his code's exec() callsites! See? Although the error's name sounds like a nice match to the internal state, it isn't really a match at all and our use of it is misleading. Unfortunately there is no EKERNELSCREWEDUP, so we usually use EINVAL. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
