On Thursday, July 10, 2014 at 01:05:39 AM, Dmitry Kasatkin wrote: > On 10 July 2014 00:00, Marek Vasut <marex@xxxxxxx> wrote: > > On Tuesday, July 08, 2014 at 10:07:16 AM, Dmitry Kasatkin wrote: > > [...] > > > >> > Right, but my concern is not about unloading the kernel module, but > >> > about the IMA module parameters left initialized. The existing code > >> > will continue using ahash (software version), even though the kernel > >> > module was unloaded, not shash. My question is about the software > >> > implementations of ahash vs. shash performance. > >> > > >> > Mimi > >> > >> If HW driver will not be available, ahash loads generic driver which is > >> using shash. > >> Performance of that will be the same as for using shash directly. > > > > Hi Dmitry, I think Mimi is concerned about the crypto accelerator dying > > mid- flight. > > > > Imagine a situation where you have a hardware crypto accelerator > > connected via USB. You happily use IMA with this setup for days and then > > someone comes around and pulls the USB cable out. Will this be able to > > cope with such situation, for example by switching to software > > operations or such in some sane way ? > > > > I presume that's the concern here. > > > > Best regards, > > Marek Vasut > > Hi Marek, Hi! > Nice to here from you. How was your rest stay at Japan? Thanks for asking, not sure there is a super-positive ultra-awesome word to express that, so in short, I had the time of my life. Love that country ;-) > I have not seen any expression of such concern. All right, that was my understanding of the entire discussion -- an accelerator dying mid-way and what will IMA do about that. > But as we fallback to early allocated shash, which is not USB yet, > then there is no problem. > ahash itself does not bring any other additional problem than shash itself. > They are compiled builtin together. Sure, I understood that. But what will happen if the ahash accelerator stops working mid-flight, will IMA also go bonkers or is there some graceful stop? Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
