Hi I'm getting the following error message when I set the current_tracer to function_graph. Procedures: cd / sys/kernel/tracing echo function_graph > current_tracer Then I saw the following message in the console. Unable to handle kernel paging request at virtual address fffffffc ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/sched/core.c:7270 migrate_disable+0x104/0x114 Modules linked in: rtc_armada38x ts7800_v2_wdt spi_orion spi_gpio i2c_gpio i2c_algo_bit CPU: 0 PID: 0 Comm: Not tainted 4.19.249-rt111-llama-rt+ #36 Hardware name: Marvell Armada 380/385 (Device Tree) [<c011424c>] (unwind_backtrace) from [<c010e318>] (show_stack+0x18/0x1c) [<c010e318>] (show_stack) from [<c09da8ac>] (dump_stack+0x84/0x98) [<c09da8ac>] (dump_stack) from [<c0124bc8>] (__warn+0x100/0x118) [<c0124bc8>] (__warn) from [<c0124d0c>] (warn_slowpath_null+0x48/0x50) [<c0124d0c>] (warn_slowpath_null) from [<c015163c>] (migrate_disable+0x104/0x114) [<c015163c>] (migrate_disable) from [<c0182920>] (vprintk_emit+0x10c/0x1ec) [<c0182920>] (vprintk_emit) from [<c0182bc0>] (vprintk_default+0x28/0x30) [<c0182bc0>] (vprintk_default) from [<c09d5100>] (printk+0x38/0x5c) [<c09d5100>] (printk) from [<c09d4dc8>] (__do_kernel_fault.part.0+0x4c/0x7c) [<c09d4dc8>] (__do_kernel_fault.part.0) from [<c0118d84>] (do_page_fault+0x380/0x394) [<c0118d84>] (do_page_fault) from [<c0118f6c>] (do_DataAbort+0x50/0xf0) ---[ end trace 0000000000000002 ]--- pgd = 721da14e [fffffffc] *pgd=2fffd861, *pte=00000000, *ppte=00000000 Internal error: Oops: 37 [#1] PREEMPT SMP ARM Modules linked in: rtc_armada38x ts7800_v2_wdt spi_orion spi_gpio i2c_gpio i2c_algo_bit CPU: 0 PID: 0 Comm: Tainted: G W 4.19.249-rt111-llama-rt+ #36 Hardware name: Marvell Armada 380/385 (Device Tree) PC is at prepare_ftrace_return+0x20/0x48 LR is at ftrace_graph_caller+0x18/0x20 pc : [<c0112884>] lr : [<c0112540>] psr: 600f0193 sp : ef12a090 ip : 00000051 fp : 00000000 r10: e9c61d7c r9 : ef12a000 r8 : 00000001 r7 : ef12a19c r6 : ffffffff r5 : 600f0193 r4 : c0112884 r3 : 00000000 r2 : 00000000 r1 : c0118f28 r0 : fffffffc Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 29c7004a DAC: 00000051 Process (pid: 0, stack limit = 0x6b08bd12) Stack: (0xef12a090 to 0xef07651c) [<c0112884>] (prepare_ftrace_return) from [<c0112540>] (ftrace_graph_caller+0x18/0x20) Code: e5933010 e593366c e3530000 18bd8070 (e5905000) ---[ end trace 0000000000000003 ]--- Kernel panic - not syncing: Attempted to kill the idle task! SMP: failed to stop secondary CPUs What is going on? Am I doing something wrong? Thanks Danilo
