Re: [PATCH v2] sparc64: increase kernel thread stack size to 32K

[Tony Rodriguez]

Hi Stian,

No problem at all, and I appreciate your honesty and for reaching out. 
It’s best to get this addressed as soon as possible if you have the time 
to work on it—I’m currently swamped with other tasks. Overall, I don’t 
mind if you take over these patches, and truly appreciate your 
assistance to the sparc64 community. Just please continue to give me a 
mention in any patches related to this work, since I spent a 
considerable amount of time debugging, researching, and validating the 
fixes.

When I last tested on 7.0 and 7.1, both of my patches worked:

A)    sparc64: increase kernel thread stack size to 32K

B)    sparc64: Fix comparator problem with timer interrupts

I was able to debug and validate these issues on S7‑2 and T7‑1 hardware. 
I’m not sure if others have reported similar problems on T4 or T5 systems.

Regarding:

STACKTRACE: hub_event():entry: 31856 bytes used
STACKTRACE: hub_activate():entry: 31680 bytes used
STACKTRACE: usb_control_msg():entry: 30768 bytes used

This was a set of debugging code inserted into function hot spots and 
scripts to measure stack usage at runtime. It helped me identify trouble 
spots and gave me a better idea of where stack consumption was highest. 
At the time, I wondered whether it might be possible to reduce the stack 
size of usbcore and the Nvidia mlx5 functions on sparc64, but that would 
be a significantly more time‑consuming task. I may have updated my stack 
monitoring script since then as well.  It’s also been a few months, so 
I’d need to refresh my memory on the details.

If you have a quicker or better methodology for reviewing stack usage—or 
any general suggestions—I’m definitely open to seeing them, along with 
your config and exact procedure. And if you need help validating against 
S7‑2 and T7‑1 hardware, I can try to allocate some time to assist.

Best regards,
Tony

On 8/31/26 11:54 AM, Stian Halseth wrote:
> Hi Tony,
>
> You're welcome.
>
> I saw it was stuck, and wanted to push it along. Looks to me like a
> proper fix that should be included.
>
> PS: Don't want to take any credit, this is 100% your fix. If you rather
> want to handle it yourself, let me know :)