On 10/21, Rabin Vincent wrote: > > On Wed, Oct 17, 2012 at 07:35:10PM +0200, Oleg Nesterov wrote: > > > > And, to clarify, I am not arguing. Just curious. > > > > So, is this like cmov on x86? And this patch allows to not report if > > the condition is not true? Or there are other issues on arm? > > Yes, I guess this is like CMOV on x86. In the ARM instruction set most > instructions can be conditionally executed. > > In order to set the probe on a conditional instruction, we use an > undefined instruction with the same condition as the instruction we > replace. However, it is implementation defined whether an undefined > instruction with a failing condition code will trigger an undefined > instruction exception or just be executed as a NOP. So for those > processor implementations where we do get the undefined instruction > exception even for a failing condition code, we have to ignore it in > order to provide consistent behaviour.
OK, I see, thanks for your explanation. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
