Re: Linux 7.0-rc4: v4l2src0:src: page allocation failure - increased memory usage in 7.0?

Harry Yoo
2026-03-20T01:02:00Z

On Thu, Mar 19, 2026 at 01:18:18AM +0100, Marek Marczykowski-Górecki wrote:
> Hello,
>
> When testing 7.0-rc4 (and also got it with 7.0-rc1), I got page
> allocation failure in uvcvideo when using v4l2 camera in a VM. The setup
> is rather memory constrained - it's a HVM with just 300MB of memory
> running on Xen, with PCI passthrough of USB controllers (to which an USB
> camera is connected). But the very same setup works just fine with older
> kernel (last known good is 6.19.5, built with the same config).

Could you please share what /proc/meminfo looks like on v6.19, and
also enable memory allocation profiling feature [1] and see
what has changed between v6.19 and v7.0?

On v6.19, you should be able to see how much memory is allocated by
reading /proc/allocinfo.

On v7.0-rc4, warn_alloc() should let memory allocation profiling
print top users.

[1] https://docs.kernel.org/mm/allocation-profiling.html

--
Cheers,
Harry / Hyeonggon