On Fri, Apr 22, 2022 at 03:42:46PM +0200, Jason A. Donenfeld wrote: > Hey Guenter, > > On Tue, Mar 22, 2022 at 6:56 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > > On 3/22/22 10:09, Jason A. Donenfeld wrote: > > > Hey Guenter, > > > > > > On Tue, Mar 22, 2022 at 08:58:20AM -0700, Guenter Roeck wrote: > > >> On Thu, Feb 17, 2022 at 05:28:48PM +0100, Jason A. Donenfeld wrote: > > >>> This topic has come up countless times, and usually doesn't go anywhere. > > >>> This time I thought I'd bring it up with a slightly narrower focus, > > >>> updated for some developments over the last three years: we finally can > > >>> make /dev/urandom always secure, in light of the fact that our RNG is > > >>> now always seeded. > > >>> > > >> > > >> [ ... ] > > >> > > >> This patch (or a later version of it) made it into mainline and causes a > > >> large number of qemu boot test failures for various architectures (arm, > > >> m68k, microblaze, sparc32, xtensa are the ones I observed). Common > > >> denominator is that boot hangs at "Saving random seed:". A sample bisect > > >> log is attached. Reverting this patch fixes the problem. > > > > > > As Linus said, it was worth a try, but I guess it just didn't work. For > > > my own curiosity, though, do you have a link to those QEMU VMs you could > > > share? I'd sort of like to poke around, and if we do ever reattempt this > > > sometime down the road, it seems like understanding everything about why > > > the previous time failed might be a good idea. > > > > > > > Everything - including the various root file systems - is at > > git@xxxxxxxxxx:groeck/linux-build-test.git. Look into rootfs/ for the > > various boot tests. I'll be happy to provide some qemu command lines > > if needed. > > I've been playing with a few things, and I'm wondering how close I am > to making this problem go away. I just made this branch: > https://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git/log/?h=jd/for-guenter > > Any interest in setting your tests on that and seeing if it still > breaks? Or, perhaps better, do you have a single script that runs all I applied your branch to my 'testing' branch. It will build tonight. We should have results by tomorrow morning. > your various tests and does all the toolchain things right, so I can > just point it at that tree and iterate? > Sorry, my system isn't that fancy. I don't mind running tests like this one, though. Guenter
