Le 21/06/2022 à 20:47, Jason A. Donenfeld a écrit : > Hi Christophe, > > On Tue, Jun 21, 2022 at 06:33:11PM +0000, Christophe Leroy wrote: >> Le 21/06/2022 à 16:08, Jason A. Donenfeld a écrit : >>> The platform's RNG must be available before random_init() in order to be >>> useful for initial seeding, which in turn means that it needs to be >>> called from setup_arch(), rather than from an init call. Fortunately, >>> each platform already has a setup_arch function pointer, which means we >>> can wire it up that way. Complicating things, however, is that POWER8 >>> systems need some per-cpu state and kmalloc, which isn't available at >>> this stage. So we split things up into an early phase and a later >>> opportunistic phase. This commit also removes some noisy log messages >>> that don't add much. >> >> Regarding the kmalloc(), I have not looked at it in details, but usually >> you can use memblock_alloc() when kmalloc is not available yet. > > That seems a bit excessive, especially as those allocations are long > lived. And we don't even *need* it that early, but just before > random_init(). Michael is running this v5 on the test rig overnight, so > we'll learn in the Australian morning whether this finally did the trick > (I hope). > The fact that they are long lived make them a good candidate for memblock_alloc(). But fair enough, if they are not required that early then just do it later. Christophe
