Re: [REGRESSION] 6.12.36+: usb: hub: post-resume delayed work triggers > uncorrected MCE / data fabric sync flood on Threadripper 7970X > (bisected to aec11e5f9c45)

On Tue, Aug 25, 2026 at 11:43:22PM +0200, Mathieu Fluhr wrote:
> The patch you sent makes the issue go away. I am now running the exact same
> scenario for 2 hours, without any crash.
That's good, thanks for confirming.

> However, I am not sure if this can qualify for a proper fix, since I
> do not have any
> external hub connected to my motherboard: All my USB devices are directly
> plugged into root hubs (and at the moment, there is only a keyboard and a
> mouse).
Yeah that's the point it only skips the 200ms hold for root hubs. The
external hubs still get their fair hold since a parent exists for them.
So external hubs are completely unaffected by this patch.

On 'proper fix', I think it is, even if we keep this bug seperate for a
moment, it makes sense to not give root hubs hold they don't need.

I'd love to hear more thoughts on the patch.

Regards,
Lovekesh