[ Sorry to spam all ] The following error/warning noticed on arm beagleboard x15 running linux next and linux mainline. [ 0.000000] Linux version 5.6.0-rc1 (oe-user@oe-host) (gcc version 7.3.0 (GCC)) #1 SMP Fri Feb 14 21:54:55 UTC 2020 [ 0.000000] CPU: ARMv7 Processor [412fc0f2] revision 2 (ARMv7), cr=30c5387d ... [ 0.000000] random: get_random_bytes called from start_kernel+0x5d0/0x798 with crng_init=0 [ 0.000000] OF: ERROR: Bad of_node_put() on /ocp/interconnect@4a000000/segment@0/target-module@8000/cm_core@0/l4per-cm@1700/l4per-clkctrl@28 [ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 5.6.0-rc1 #1 [ 0.000000] Hardware name: Generic DRA74X (Flattened Device Tree) [ 0.000000] Backtrace: [ 0.000000] [<c040fabc>] (dump_backtrace) from [<c040fdf0>] (show_stack+0x20/0x24) [ 0.000000] r7:c23f1460 r6:00000000 r5:600000d3 r4:c23f1460 [ 0.000000] [<c040fdd0>] (show_stack) from [<c13e0cf0>] (dump_stack+0xe8/0x114) [ 0.000000] [<c13e0c08>] (dump_stack) from [<c1127c0c>] (of_node_release+0xb4/0xcc) [ 0.000000] r10:efca9a44 r9:00000001 r8:00000000 r7:00000000 r6:c23d1250 r5:efca9a44 [ 0.000000] r4:efca9a70 r3:aac0aa55 [ 0.000000] [<c1127b58>] (of_node_release) from [<c13e6448>] (kobject_put+0x11c/0x23c) [ 0.000000] r5:c2421020 r4:efca9a70 [ 0.000000] [<c13e632c>] (kobject_put) from [<c1126ed8>] (of_node_put+0x24/0x28) [ 0.000000] r7:e98f6940 r6:c2201ef4 r5:00000000 r4:e98f6900 [ 0.000000] [<c1126eb4>] (of_node_put) from [<c2047540>] (of_clk_init+0x1a4/0x248) [ 0.000000] [<c204739c>] (of_clk_init) from [<c20141bc>] (omap_clk_init+0x4c/0x68) [ 0.000000] r10:efc8b8c0 r9:c243129c r8:00000000 r7:c2208700 r6:00000066 r5:c20daf64 [ 0.000000] r4:c2432740 [ 0.000000] [<c2014170>] (omap_clk_init) from [<c2014bdc>] (omap4_sync32k_timer_init+0x18/0x3c) [ 0.000000] r5:c20daf64 r4:c2431240 [ 0.000000] [<c2014bc4>] (omap4_sync32k_timer_init) from [<c2014ec8>] (omap5_realtime_timer_init+0x1c/0x258) [ 0.000000] [<c2014eac>] (omap5_realtime_timer_init) from [<c2005a38>] (time_init+0x30/0x44) [ 0.000000] r9:c243129c r8:00000000 r7:c2208700 r6:00000066 r5:c20daf64 r4:c2431240 [ 0.000000] [<c2005a08>] (time_init) from [<c20013bc>] (start_kernel+0x604/0x798) [ 0.000000] [<c2000db8>] (start_kernel) from [<00000000>] (0x0) [ 0.000000] r10:30c5387d r9:412fc0f2 r8:8ffdc000 r7:00000000 r6:30c0387d r5:00000000 [ 0.000000] r4:c2000330 [ 0.000000] OMAP clockevent source: timer1 at 32786 Hz [ 0.000000] arch_timer: cp15 timer(s) running at 6.14MHz (phys). [ 0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x16af5adb9, max_idle_ns: 440795202250 ns [ 0.000006] sched_clock: 56 bits at 6MHz, resolution 162ns, wraps every 4398046511023ns [ 0.000028] Switching to timer-based delay loop, resolution 162ns [ 0.005242] clocksource: 32k_counter: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 58327039986419 ns [ 0.005261] OMAP clocksource: 32k_counter at 32768 Hz [ 0.012808] ------------[ cut here ]------------ [ 0.012814] WARNING: CPU: 0 PID: 0 at /usr/src/kernel/lib/refcount.c:25 refcount_warn_saturate+0x108/0x174 [ 0.012818] refcount_t: addition on 0; use-after-free. [ 0.012821] Modules linked in: [ 0.012828] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc1 #1 [ 0.012831] Hardware name: Generic DRA74X (Flattened Device Tree) [ 0.012834] Backtrace: [ 0.012841] [<c040fabc>] (dump_backtrace) from [<c040fdf0>] (show_stack+0x20/0x24) [ 0.012844] r7:c23f1460 r6:00000000 r5:600000d3 r4:c23f1460 [ 0.012848] [<c040fdd0>] (show_stack) from [<c13e0cf0>] (dump_stack+0xe8/0x114) [ 0.012852] [<c13e0c08>] (dump_stack) from [<c04595d0>] (__warn+0x100/0x118) [ 0.012856] r10:efca9a50 r9:c09577c8 r8:00000019 r7:c1c1c6c0 r6:00000009 r5:00000000 [ 0.012859] r4:c2201b7c r3:aac0aa55 [ 0.012862] [<c04594d0>] (__warn) from [<c045966c>] (warn_slowpath_fmt+0x84/0xc0) [ 0.012866] r9:00000009 r8:c09577c8 r7:00000019 r6:c1c1c6c0 r5:c1c1c6e0 r4:c2208708 [ 0.012870] [<c04595ec>] (warn_slowpath_fmt) from [<c09577c8>] (refcount_warn_saturate+0x108/0x174) [ 0.012873] r9:c2a34254 r8:c2a33e96 r7:c2a33e96 r6:00000007 r5:efca9a50 r4:efca9a70 [ 0.012877] [<c09576c0>] (refcount_warn_saturate) from [<c13e6250>] (kobject_get+0xa8/0xac) [ 0.012881] [<c13e61a8>] (kobject_get) from [<c1126eac>] (of_node_get+0x24/0x2c) [ 0.012884] r4:efca9a44 [ 0.012887] [<c1126e88>] (of_node_get) from [<c1125d3c>] (of_fwnode_get+0x44/0x50) [ 0.012890] r5:efca9a50 r4:00000007 [ 0.012894] [<c1125cf8>] (of_fwnode_get) from [<c0cbc270>] (fwnode_get_nth_parent+0x3c/0x6c) [ 0.012898] [<c0cbc234>] (fwnode_get_nth_parent) from [<c13f4e44>] (fwnode_full_name_string+0x3c/0xa8) [ 0.012901] r7:c2a33e96 r6:c1c4d59d r5:c189ae2c r4:00000007 [ 0.012904] [<c13f4e08>] (fwnode_full_name_string) from [<c13f686c>] (device_node_string+0x48c/0x4ec) [ 0.012908] r10:ffffffff r9:c1bd7a4c r8:efca9a44 r7:c2a33e96 r6:c1c4d59d r5:c2a34254 [ 0.012911] r4:c2208708 [ 0.012915] [<c13f63e4>] (device_node_string) from [<c13f843c>] (pointer+0x43c/0x4e0) [ 0.012918] r10:c2a34254 r9:c2201d3c r8:c2201e90 r7:00000002 r6:00000000 r5:c2a34254 [ 0.012921] r4:c2a33e96 [ 0.012925] [<c13f8000>] (pointer) from [<c13f86a8>] (vsnprintf+0x1c8/0x414) [ 0.012928] r7:00000002 r6:c1d5476c r5:c1d5476a r4:c2a33e96 [ 0.012931] [<c13f84e0>] (vsnprintf) from [<c13f8908>] (vscnprintf+0x14/0x2c) [ 0.012935] r10:00000000 r9:00000000 r8:ffffffff r7:c2a33528 r6:00000028 r5:600000d3 [ 0.012938] r4:000003e0 [ 0.012942] [<c13f88f4>] (vscnprintf) from [<c04db308>] (vprintk_store+0x44/0x220) [ 0.012945] r5:600000d3 r4:c2a33528 [ 0.012949] [<c04db2c4>] (vprintk_store) from [<c04db8a8>] (vprintk_emit+0xa0/0x2fc) [ 0.012953] r10:00000001 r9:ffffffff r8:00000000 r7:00000000 r6:00000028 r5:600000d3 [ 0.012956] r4:c2a33528 [ 0.012959] [<c04db808>] (vprintk_emit) from [<c04dbb34>] (vprintk_default+0x30/0x38) [ 0.012963] r10:efca9a44 r9:00000001 r8:00000000 r7:ffffe000 r6:c2201e8c r5:c1d54748 [ 0.012966] r4:c21a8590 [ 0.012970] [<c04dbb04>] (vprintk_default) from [<c04dc9dc>] (vprintk_func+0xe0/0x168) [ 0.012974] [<c04dc8fc>] (vprintk_func) from [<c04dc1f4>] (printk+0x40/0x5c) [ 0.012977] r7:00000000 r6:c23d1250 r5:efca9a44 r4:c2208708 [ 0.012981] [<c04dc1b4>] (printk) from [<c1127c08>] (of_node_release+0xb0/0xcc) [ 0.012984] r3:00000008 r2:00000000 r1:efca9a44 r0:c1d54748 [ 0.012987] r4:efca9a70 [ 0.012991] [<c1127b58>] (of_node_release) from [<c13e6448>] (kobject_put+0x11c/0x23c) [ 0.012994] r5:c2421020 r4:efca9a70 [ 0.012998] [<c13e632c>] (kobject_put) from [<c1126ed8>] (of_node_put+0x24/0x28) [ 0.013001] r7:e98f6940 r6:c2201ef4 r5:00000000 r4:e98f6900 [ 0.013005] [<c1126eb4>] (of_node_put) from [<c2047540>] (of_clk_init+0x1a4/0x248) [ 0.013009] [<c204739c>] (of_clk_init) from [<c20141bc>] (omap_clk_init+0x4c/0x68) [ 0.013013] r10:efc8b8c0 r9:c243129c r8:00000000 r7:c2208700 r6:00000066 r5:c20daf64 [ 0.013016] r4:c2432740 [ 0.013020] [<c2014170>] (omap_clk_init) from [<c2014bdc>] (omap4_sync32k_timer_init+0x18/0x3c) [ 0.013023] r5:c20daf64 r4:c2431240 [ 0.013027] [<c2014bc4>] (omap4_sync32k_timer_init) from [<c2014ec8>] (omap5_realtime_timer_init+0x1c/0x258) [ 0.013031] [<c2014eac>] (omap5_realtime_timer_init) from [<c2005a38>] (time_init+0x30/0x44) [ 0.013034] r9:c243129c r8:00000000 r7:c2208700 r6:00000066 r5:c20daf64 r4:c2431240 [ 0.013038] [<c2005a08>] (time_init) from [<c20013bc>] (start_kernel+0x604/0x798) [ 0.013042] [<c2000db8>] (start_kernel) from [<00000000>] (0x0) [ 0.013045] r10:30c5387d r9:412fc0f2 r8:8ffdc000 r7:00000000 r6:30c0387d r5:00000000 [ 0.013048] r4:c2000330 [ 0.013051] irq event stamp: 0 [ 0.013055] hardirqs last enabled at (0): [<00000000>] 0x0 [ 0.013058] hardirqs last disabled at (0): [<00000000>] 0x0 [ 0.013062] softirqs last enabled at (0): [<00000000>] 0x0 [ 0.013065] softirqs last disabled at (0): [<00000000>] 0x0 [ 0.013069] ---[ end trace dc03abb39d272e33 ]--- [ 0.013072] ------------[ cut here ]------------ ref: https://qa-reports.linaro.org/lkft/linux-mainline-oe/build/v5.6-rc1-186-g2019fc96af22/testrun/1221060/log -- Linaro LKFT https://lkft.linaro.org