I have a zynq 7020 embedded board running openwrt with 5.15.118 kernel. When I do a power cycle test, the board generally boots up but occasionally fails with following logs. [ 0.730000] 8<--- cut here --- [ 0.740000] Unable to handle kernel paging request at virtual address ffffffff [ 0.740000] pgd = (ptrval) [ 0.750000] [ffffffff] *pgd=200f6861, *pte=00000000, *ppte=00000000 [ 0.750000] Internal error: Oops: 37 [#1] SMP ARM [ 0.750000] Modules linked in: [ 0.750000] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.118 #0 [ 0.750000] Hardware name: Xilinx Zynq Platform [ 0.750000] PC is at internal_create_group+0x94/0x3ac [ 0.750000] LR is at internal_create_group+0x78/0x3ac [ 0.750000] pc : [<c02b68f0>] lr : [<c02b68d4>] psr: a0000053 [ 0.750000] sp : c0055e30 ip : 00000000 fp : 00000000 [ 0.750000] r10: c083efe0 r9 : c0f88d68 r8 : c0fc0044 [ 0.750000] r7 : 00000000 r6 : c097d3f4 r5 : ffffffff r4 : c0fc0000 [ 0.750000] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : c0f88d68 [ 0.750000] Flags: NzCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment none [ 0.750000] Control: 18c5387d Table: 0020404a DAC: 00000051 [ 0.750000] Register r0 information: slab kernfs_node_cache start c0f88d68 pointer offset 0 [ 0.750000] Register r1 information: NULL pointer [ 0.750000] Register r2 information: NULL pointer [ 0.750000] Register r3 information: NULL pointer [ 0.750000] Register r4 information: slab request_queue start c0fc0000 pointer offset 0 [ 0.750000] Register r5 information: non-paged memory [ 0.750000] Register r6 information: non-slab/vmalloc memory [ 0.750000] Register r7 information: NULL pointer [ 0.750000] Register r8 information: slab request_queue start c0fc0000 pointer offset 68 [ 0.750000] Register r9 information: slab kernfs_node_cache start c0f88d68 pointer offset 0 [ 0.750000] Register r10 information: non-slab/vmalloc memory [ 0.750000] Register r11 information: NULL pointer [ 0.750000] Register r12 information: NULL pointer [ 0.750000] Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) [ 0.750000] Stack: (0xc0055e30 to 0xc0056000) [ 0.750000] 5e20: c097e580 c097e580 c0fc0044 00000000 [ 0.750000] 5e40: 00000000 00000000 00000000 00000000 c0a40368 c0fc0000 00000000 c0a40368 [ 0.750000] 5e60: c0fc0044 c0fc0470 c0a40368 c083efe0 00000000 c0368e58 c0f55240 c0a40340 [ 0.750000] 5e80: c0a40340 c09c58d0 00000000 c0a40368 c083efe0 c037a9e4 c0f55240 00000004 [ 0.750000] 5ea0: c0f5f5c0 00000000 c0f5524c c0995020 c083efe0 c043ffcc c0a10b28 306d6172 [ 0.750000] 5ec0: c0753000 c0253348 c0a12220 c0a10b28 c0a12220 c0334360 c0995008 7450f831 [ 0.750000] 5ee0: c0983f70 c09c6e68 00000001 c0983f78 c083701c c081eec8 c0995008 c081edf8 [ 0.750000] 5f00: ffffe000 00000000 c083701c c01017ec c01751d0 00000000 00000081 00000000 [ 0.750000] 5f20: c003f2e0 c003f2e6 c07c305c 00000080 00000081 c013ca18 c0761f90 00000000 [ 0.750000] 5f40: 00000006 00000006 c003f2e6 00000000 c083ec44 00000081 c003f280 7450f831 [ 0.750000] 5f60: 00000006 00000081 c003f280 c083703c 00000006 c08013d0 00000006 00000006 [ 0.750000] 5f80: 00000000 c0800524 00000000 c0669474 00000000 00000000 00000000 00000000 [ 0.750000] 5fa0: 00000000 c0669488 00000000 c0100130 00000000 00000000 00000000 00000000 [ 0.750000] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 0.750000] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [ 0.750000] [<c02b68f0>] (internal_create_group) from [<c0368e58>] (blk_register_queue+0x5c/0x194) [ 0.750000] [<c0368e58>] (blk_register_queue) from [<c037a9e4>] (device_add_disk+0x1a4/0x3f0) [ 0.750000] [<c037a9e4>] (device_add_disk) from [<c043ffcc>] (brd_alloc+0x220/0x2a8) [ 0.750000] [<c043ffcc>] (brd_alloc) from [<c081eec8>] (brd_init+0xd0/0x150) [ 0.750000] [<c081eec8>] (brd_init) from [<c01017ec>] (do_one_initcall+0x54/0x1f4) [ 0.750000] [<c01017ec>] (do_one_initcall) from [<c08013d0>] (kernel_init_freeable+0x228/0x27c) [ 0.750000] [<c08013d0>] (kernel_init_freeable) from [<c0669488>] (kernel_init+0x14/0x124) [ 0.750000] [<c0669488>] (kernel_init) from [<c0100130>] (ret_from_fork+0x14/0x24) [ 0.750000] Exception stack(0xc0055fb0 to 0xc0055ff8) [ 0.750000] 5fa0: 00000000 00000000 00000000 00000000 [ 0.750000] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 0.750000] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 0.750000] Code: e3550000 e59d301c e58d3010 0a000042 (e5953000) [ 0.760000] ---[ end trace a4ae197d2ac7d4bd ]--- [ 0.770000] Kernel panic - not syncing: Fatal exception [ 0.770000] Rebooting in 1 seconds.. [ 0.770000] Reboot failed -- System halted If I move to the 6.1.55 kernel, I have a similar failure at internal_create_group but the path is a bit different. [ 0.790000] internal_create_group from internal_create_groups+0x48/0x8c [ 0.790000] internal_create_groups from device_add+0x2a0/0x7a8 [ 0.790000] device_add from __mdiobus_register+0xb8/0x340 [ 0.790000] __mdiobus_register from fixed_mdio_bus_init+0xc0/0xec [ 0.790000] fixed_mdio_bus_init from do_one_initcall+0x48/0x244 [ 0.790000] do_one_initcall from kernel_init_freeable+0x208/0x25c [ 0.790000] kernel_init_freeable from kernel_init+0x1c/0x12c [ 0.790000] kernel_init from ret_from_fork+0x14/0x28 [ 0.790000] Exception stack(0xc005bfb0 to 0xc005bff8) What might be the issue?
