No, Pi3B+ fails with RCU-related issues in the DWC driver. The focus is on whether PREEMPT_RT is a useful kernel to support on Pi5 and Pi4, Pi5 has more memory bandwidth which should help.@timg236,
Here's a screen capture of the -v8-rt kernel on a Raspberry Pi 3B+:
IMG_0048.jpg
Are you (or anyone else) successful running on a Raspberry Pi 3B+?
Example Pi3B+ panic
Code:
[ 1.988791] mmc1: new high speed SDIO card at address 0001[ 2.038769] ------------[ cut here ]------------[ 2.038776] Voluntary context switch within RCU read-side critical section![ 2.038795] WARNING: CPU: 1 PID: 93 at kernel/rcu/tree_plugin.h:331 rcu_note_context_switch+0x504/0x550[ 2.038816] Modules linked in:[ 2.038824] CPU: 1 UID: 0 PID: 93 Comm: irq/74-dwc_otg Not tainted 6.12.30-v8-rt+ #1[ 2.038831] Hardware name: Raspberry Pi 3 Model B Plus Rev 1.4 (DT)[ 2.038835] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)[ 2.038841] pc : rcu_note_context_switch+0x504/0x550[ 2.038849] lr : rcu_note_context_switch+0x504/0x550[ 2.038857] sp : ffffffc080b5bbb0[ 2.038860] x29: ffffffc080b5bbb0 x28: ffffffd036326aa8 x27: ffffff8003b7d400[ 2.038870] x26: ffffff8003a1c280 x25: ffffffd0379d9780 x24: ffffffd036f9cb3c[ 2.038878] x23: 0000000000000000 x22: ffffff8003a1c280 x21: ffffffd037c09ef0[ 2.038887] x20: 0000000000000000 x19: ffffff803b199a00 x18: ffffffffffffffff[ 2.038895] x17: 0000000000000000 x16: 000000005bca3b63 x15: ffffffc080c23810[ 2.038903] x14: 0000000000000001 x13: 216e6f6974636573 x12: 206c616369746972[ 2.038911] x11: 6320656469732d64 x10: 6165722055435220 x9 : ffffffd03631fbdc[ 2.038920] x8 : 6863746977732074 x7 : 7865746e6f632079 x6 : 7261746e756c6f56[ 2.038928] x5 : ffffff803b185408 x4 : 0000000000000000 x3 : 0000000000000027[ 2.038936] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffff8003a1c280[ 2.038945] Call trace:[ 2.038947] rcu_note_context_switch+0x504/0x550[ 2.038956] __schedule+0xac/0xb60[ 2.038963] schedule+0x3c/0x148[ 2.038969] __synchronize_irq+0x90/0xc8[ 2.038976] disable_irq+0x44/0x60[ 2.038981] local_fiq_disable+0x28/0x40[ 2.038989] dwc_otg_handle_common_intr+0x488/0x16b0[ 2.039000] dwc_otg_common_irq+0x1c/0x38[ 2.039009] irq_forced_thread_fn+0x44/0xd8[ 2.039014] irq_thread+0x184/0x278[ 2.039020] kthread+0x118/0x128[ 2.039027] ret_from_fork+0x10/0x20Statistics: Posted by timg236 — Wed Jun 04, 2025 8:57 am