The default SDK gives the entire MSMC to C7x as SRAM(Barring 128KB for ATF and 64KB for DMSC). The user may wants to share MSMC between C7x(as SRAM) & A72(L3 Cache).

With this setup: C7x is continuously running application in the background & in parallel the
iperf3 is run on the A72 side. There is a crash around 20-30 minutes. This can be reproduced on CPSW2G & CPSW9G as well.

Logs:

root@j7-evm:/opt/vision_apps# ./run_app_c7x.sh
APP: Init ... !!!
MEM: Init ... !!!
MEM: Initialized DMA HEAP (fd=4) !!!
MEM: Init ... Done !!!
IPC: Init ... !!!
IPC: Init ... Done !!!
REMOTE_SERVICE: Init ... !!!
REMOTE_SERVICE: Init ... Done !!!
50160.837722 s: GTC Frequency = 200 MHz
APP: Init ... Done !!!
50160.849033 s: VX_ZONE_INIT:Enabled
50160.849043 s: VX_ZONE_ERROR:Enabled
50160.849056 s: VX_ZONE_WARNING:Enabled
50160.852523 s: VX_ZONE_INIT:[tivxInitLocal:130] Initialization Done !!!
50160.852724 s: VX_ZONE_INIT:[tivxHostInitLocal:86] Initialization Done for HOST !!!
[C7x_1 ] 50160.877972 s: — umap src_desc0_target_ptr 0xb8000000 0.054932 MB
[C7x_1 ] 50160.877999 s: — umap src_desc1_target_ptr 0xb8010000 7.000000 MB
[C7x_1 ] 50160.878023 s: — umap dst_desc_target_ptr 0xb8710000 7.000000 MB
[ 999.745257] ----------[ cut here ]----------
[ 999.749868] kernel BUG at lib/genalloc.c:507!
[ 999.754210] Internal error: Oops - BUG: 0 1 PREEMPT SMP
[ 999.759678] Modules linked in: xt_conntrack xt_MASQUERADE xt_addrtype iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ip6
[ 999.839972] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 5.10.100-g7a7a3af903 #8
[ 999.848472] Hardware name: Texas Instruments K3 J721E SoC (DT)
[ 999.854288] pstate: 00000005 (nzcv daif PAN UAO -TCO BTYPE=)
[ 999.860282] pc : gen_pool_free_owner+0xf4/0x170
[ 999.864797] lr : gen_pool_free_owner+0xa8/0x170
[ 999.869310] sp : ffff80001138fcd0
[ 999.872610] x29: ffff80001138fcd0 x28: 0000000000000000
[ 999.877907] x27: ffff80001138fe30 x26: ffff000824122108
[ 999.883203] x25: ffff00082404e000 x24: 0000000000000007
[ 999.888498] x23: ffff0008245b007f x22: 0000000000000000
[ 999.893794] x21: 0000000000000001 x20: ffff00082426b600
[ 999.899089] x19: ffff0008245b0000 x18: ffff00082a3b1914
[ 999.904385] x17: 0000000000000000 x16: 0000000000000000
[ 999.909681] x15: ffff00082a3b1904 x14: 00000000000002dd
[ 999.914977] x13: 0000000000000000 x12: ffff800011d20000
[ 999.920272] x11: 0000000000000001 x10: 0000000000000000
[ 999.925568] x9 : 0000000000000040 x8 : 0000000000000001
[ 999.930863] x7 : ffff800011d20038 x6 : 0000000000000000
[ 999.936158] x5 : fffffffffffffffe x4 : 0000000000000001
[ 999.941453] x3 : ffff800011d20038 x2 : 0000000000000001
[ 999.946749] x1 : 0000000000000002 x0 : 0000000000000001
[ 999.952044] Call trace:
[ 999.954481] gen_pool_free_owner+0xf4/0x170
[ 999.958651] k3_cppi_desc_pool_free+0x1c/0x28
[ 999.962992] am65_cpsw_nuss_xmit_free+0xf8/0x128
[ 999.967593] am65_cpsw_nuss_tx_compl_packet+0x50/0xa0
[ 999.972627] am65_cpsw_nuss_tx_poll+0x1a8/0x3a8
[ 999.977143] net_rx_action+0x118/0x380
[ 999.980878] efi_header_end+0x120/0x268
[ 999.984699] irq_exit+0xc0/0xe0
[ 999.987827] __handle_domain_irq+0x68/0xc0
[ 999.991909] gic_handle_irq+0x58/0x128
[ 999.995643] el1_irq+0xcc/0x180
[ 999.998772] arch_cpu_idle+0x18/0x28
[ 1000.002334] default_idle_call+0x20/0x68
[ 1000.006242] do_idle+0xc0/0x128
[ 1000.009370] cpu_startup_entry+0x28/0x60
[ 1000.013278] rest_init+0xd4/0xe4
[ 1000.016493] arch_call_rest_init+0x10/0x1c
[ 1000.020574] start_kernel+0x48c/0x4c4
[ 1000.024224] Code: d65f03c0 1400001c 17fffff5 d4210000 (d4210000)
[ 1000.030304] -[ end trace 00385cdf2f07788f ]-
[ 1000.034905] Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt
[ 1000.042279] SMP: stopping secondary CPUs
[ 1000.046195] Kernel Offset: disabled
[ 1000.049669] CPU features: 0x0040022,20006008
[ 1000.053923] Memory Limit: none

[ 1000.056966] -[ end Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt ]-