Bisecting is pointing to the below commit and reverting it fixes the above issues ...
# first bad commit: [26c5e136ba4e94ad708333c9bd34039a1de397b0] net: stmmac: protect updates of 64-bit statistics counters
Thanks for bisecting. 6.1 is missing a prerequisite for that backport.
38cc3c6dcc09 ("net: stmmac: protect updates of 64-bit statistics counters") allocates priv->xstats.pcpu_stats in stmmac_dvr_probe(). 6.1 does not have 2eb85b750512 ("net: stmmac: don't clear network statistics in .ndo_open()"), so the memset() of priv->xstats in __stmmac_open() zeroes that pointer on every ifup, and the first DMA interrupt on a dwmac4 device (Tegra186/194 EQOS) dereferences a NULL percpu pointer.
Greg has queued a revert of the backport for 6.1, so this goes away in the next 6.1 release. 38cc3c6dcc09 can come back to 6.1 later together with 2eb85b750512.
Could you test if adding in 2eb85b750512 fixes the issue?