Hi Stephan, Thanks for quick reply, On 27-06-18, 08:43, Stephan Mueller wrote: > > On 27-06-18, 08:13, Stephan Mueller wrote: > > > The key is: > > > alg->base.cra_ctxsize = sizeof(struct drbg_state); > > > > > > during initialization since the kernel crypto API allocates that buffer > > > for > > > you and releases it during deallocation. > > > > The difference here is that memory is allocated by crypto and driver has > > no way to pass "it's" own data while doing registration. Ideally > > registration should accept a pointer/long and pass that back on a > > callbacks > > Looking at your code, it seems you do what makes sense: there is only one > instance of the driver, if at all. Thus, having qcom_rng_dev as static makes > sense. The kernel crypto API allows arbitrary instances of the RNG as well as > frequent allocations and deallocations. And this is why there must be a > disconnect between the one hardware-resource driver-instance data structure > and the (potentially) multiple crypto API RNG instances and their data > structures. For now it is true, but somehow doesn't make me happy to bank on that.. > > > > Currently am doing bunch of initialization in .probe (platform driver) > > and I think recommendation would be to move that to .cra_init, which seem > > plausible but I don't have pdev to read hw_resource etc.. so would still > > need to get that. > > It seems that your allocation during probe relates to the hardware resource > where you only have one in the system. Thus, doing the allocation here makes > sense. And, you do not want to perform probe or such resource allocation once > per crypto API RNG instance allocation. As said, there can be multiple or even > they can be allocated and deallocated frequently. This in particular applies > if your driver's "stdrng" has the highest prio which means that it will be > allocated and deallocated frequently. Right, that is how I visualized it. Is there a way where we can tweak the register API to pass hw_resource pointer and get that back? Would that work with the security model in crypto. I do not like globals and somehow don't feel that we should do it that way Thanks for the quick look on the code. ~Vinod
