From: Guenter Roeck > Sent: 22 March 2022 21:54 > > On 3/22/22 11:24, Mark Brown wrote: > > On Tue, Mar 22, 2022 at 08:58:20AM -0700, Guenter Roeck wrote: > > > >> 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. > > > > Just as a datapoint for debugging at least qemu/arm is getting coverage > > in CI systems (KernelCI is covering a bunch of different emulated > > machines and LKFT has at least one configuration as well, clang's tests > > have some wider architecture coverage as well I think) and they don't > > seem to be seeing any problems - there's some other variable in there. > > > > For example current basic boot tests for KernelCI are at: > > > > https://linux.kernelci.org/test/job/mainline/branch/master/kernel/v5.17-1442- > gb47d5a4f6b8d/plan/baseline/ > > > > for mainline and -next has: > > > > https://linux.kernelci.org/test/job/next/branch/master/kernel/next-20220322/plan/baseline/ > > > > These are with a buildroot based rootfs that has a "Saving random seed: " > > step in the boot process FWIW. > > I use buildroot 2021.02.3. I have not changed the buildroot code, and it > still seems to be the same in 2022.02. I don't see the problem with all > boot tests, only with the architectures mentioned above, and not with all > qemu machines on the affected platforms. For arm, mostly older machines > are affected (versatile, realview, pxa configurations, collie, integratorcp, > sx1, mps2-an385, vexpress-a9, cubieboard). I didn't check, but maybe > kernelci doesn't test those machines ? I was trying to fix the buildroot save/restore random seed of a system of mine. I thought I'd fixed it - needed to use a persistent filesystem. But I can't get rid of the 'uninitialised random read' messages. (Which I expected to go away after writing the seed.) But a quick look at the kernel code didn't seem to credit the write into the correct logic. I didn't check whether the data actually got used though. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)