Test kernel available - was: Re: 5.10.0-4-sparc64-smp #1 Debian 5.10.19-1 crashes on T2000

Test kernel available - was: Re: 5.10.0-4-sparc64-smp #1 Debian 5.10.19-1 crashes on T2000

[John Paul Adrian Glaubitz]

Hi Frank and Ricardo,

On Wed, 2022-02-02 at 15:27 +0100, Frank Scheiner wrote:
> I yesterday found the time to give Linux 5.15.0-3 a try on my T1000
> (UltraSPARC T1) and V210 (US IIIi), but the boot issue is still there -
> at least for my use case: The klibc based tools inside of the initramfs
> are not able to mount the root FS over NFS (details further below).
> 
> But it's still good to see that mounting an on-disk root FS seems to
> work now for your T2000, though the instabilities during runtime are not
> reassuring.
> 
> For me the last good Debian kernel - at least for booting, more on that
> shortly - is 5.9.0-5. Both T1000 and V210 boot fine with it (incl.
> mounting the root FS via NFS(v3 BTW)). But during operation (tested with
> `apt upgrade` on a root FS replicated multiple times for testing from
> the same tarball) the V210 crashes (=> kernel panic), the T1000 does
> not. For the V210 I also see that for 5.8.0-3. Doing the same with
> kernel 4.19.0-5 running on the V210, no problems are seen, not even the
> messages below.
> 
> The crash when running 5.9.0-5 or 5.8.0-3 is usually "announced" (or at
> least accompanied) by one or more occurrence(s) of the following messages:
> ```
> [...]
> [  360.489852] CPU[0]: Cheetah+ D-cache parity error at
> TPC[00000000005b28c8]
> [  360.580300] TPC<bpf_check+0x1f68/0x34e0>
> [...]
> ```
> ...which should be familiar for UltraSPARC IIIi users with newer kernels
> (see for example [1] which shows it for 4.16.x). According to [2] this
> error should be recoverable (otherwise it would be followed by a panic
> and "Irrecoverable Cheetah+ parity error."), which seems to happen,
> until it is no longer, but I don't see that second message, so something
> else must happen.
> 
> [1]: https://www.spinics.net/lists/sparclinux/msg21019.html
> 
> [2]:
> https://github.com/torvalds/linux/blob/master/arch/sparc/kernel/traps_64.c#L1767..L1799
> 
> Of course our CPU's caches don't go pop magically. There is something
> broken in the newer kernels (> 4.19.x) for UltraSPARC IIIi (and most
> likely all the other related processors, too), apart from the mounting
> issues for NFS (see [3] for processors affected by this, update to that:
> US II is not affected, too).
> 
> [3]: https://lists.debian.org/debian-sparc/2021/12/msg00004.html
> 
> If I find the time and mood I'll try to bisect this US IIIi specific
> issue in the hope that we will eventually get a fix for it, also still
> hoping for a fix for [4].
> 
> [4]: https://lists.debian.org/debian-sparc/2021/03/msg00045.html

Can either of you test the following kernel packages on your T1000 or T2000:

https://people.debian.org/~glaubitz/sparc64/

These contain a potential fix for the crash you are seeing.

If the kernel works for you, please reply to the following message with a
"Tested-by":

https://lore.kernel.org/all/20250826160312.2070-4-kernel@mkarcher.dialup.fu-berlin.de/

If you are not subscribed to the sparclinux kernel mailing list, you can reply
to the message by downloading the following mbox file and importing it into
your mail client of choice, then reply to the imported mail:

https://lore.kernel.org/all/20250826160312.2070-4-kernel@mkarcher.dialup.fu-berlin.de/raw

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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