Messages in this thread | | | From | Rabin Vincent <> | Date | Sat, 17 Sep 2011 11:37:26 +0530 | Subject | Re: [PATCH] ARM: BUG() dies silently |
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On Fri, Apr 1, 2011 at 01:45, Omar Ramirez Luna <omar.ramirez@ti.com> wrote: > There are some cases where the code generated for BUG() results > into an infinite while loop without causing a null dereference, > this ends on a kernel being stuck on a loop and the user without > a clue of what happened. > > E.g.: lib/scatterlist.c : __sg_alloc_table > > BUG_ON(nents > max_ents); > 438: 9a000000 bls 440 <__sg_alloc_table+0x20> > 43c: eafffffe b 43c <__sg_alloc_table+0x1c> > > Adding volatile makes the compiler to avoid optimizations on this > code, which makes the panic to occur: > > BUG_ON(nents > max_ents); > 438: 9a000002 bls 448 <__sg_alloc_table+0x28> > 43c: e3a03000 mov r3, #0 > 440: e5833000 str r3, [r3] > 444: eafffffc b 43c <__sg_alloc_table+0x1c> > > Seen with gnu/linux cs arm-2010q1-202 and arm2010.09-50. > > Signed-off-by: Omar Ramirez Luna <omar.ramirez@ti.com>
If the "Use generic BUG() handler" patch is only scheduled for the next merge window and not for 3.1, can this patch be merged instead for 3.1 and -stable? This problem is easily seen with GCC 4.6. -- 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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