Re: [GIT PULL] Please pull powerpc/linux.git powerpc-6.1-1 tag

From: Jason A. Donenfeld
Date: Wed Oct 12 2022 - 12:46:03 EST


On Wed, Oct 12, 2022 at 09:49:26AM -0600, Jason A. Donenfeld wrote:
> On Wed, Oct 12, 2022 at 07:18:27AM -0700, Guenter Roeck wrote:
> > NIP [c000000000031630] .replay_soft_interrupts+0x60/0x300
> > LR [c000000000031964] .arch_local_irq_restore+0x94/0x1c0
> > Call Trace:
> > [c000000007df3870] [c000000000031964] .arch_local_irq_restore+0x94/0x1c0 (unreliable)
> > [c000000007df38f0] [c000000000f8a444] .__schedule+0x664/0xa50
> > [c000000007df39d0] [c000000000f8a8b0] .schedule+0x80/0x140
> > [c000000007df3a50] [c00000000092f0dc] .try_to_generate_entropy+0x118/0x174
> > [c000000007df3b40] [c00000000092e2e4] .urandom_read_iter+0x74/0x140
> > [c000000007df3bc0] [c0000000003b0044] .vfs_read+0x284/0x2d0
> > [c000000007df3cd0] [c0000000003b0d2c] .ksys_read+0xdc/0x130
> > [c000000007df3d80] [c00000000002a88c] .system_call_exception+0x19c/0x330
> > [c000000007df3e10] [c00000000000c1d4] system_call_common+0xf4/0x258
>
> Obviously the first couple lines of this concern me a bit. But I think
> actually this might just be a catalyst for another bug. You could view
> that function as basically just:
>
> while (something)
> schedule();
>
> And I guess in the process of calling the scheduler a lot, which toggles
> interrupts a lot, something got wedged.
>
> Curious, though, I did try to reproduce this, to no avail. My .config is
> https://xn--4db.cc/rBvHWfDZ . What's yours?

I also just tried using your github linux-build-test scripts as a guide
for construction a config -- https://xn--4db.cc/B0HpEQDQ -- and loaded
up your rootfs over sdhci and such, and still couldn't manage to
reproduce. I tried commenting out the line "if (!bits)" in
_credit_init_bits(), so that the rng would never initialize, so that the
schedule() loop would just keep on running indefinitely, but still no
dice.

But also, I'm running Linus' tree. From your log, I see
"6.0.0-rc2-00163-ga5edf9815dd7". So maybe these bugs got fixed
elsewhere?

Jason