Hi David, On 27/04/16 19:52, David Long wrote: > From: "David A. Long" <dave.l...@linaro.org> > > This patchset is heavily based on Sandeepa Prabhu's ARM v8 kprobes patches, > first seen in October 2013. This version attempts to address concerns raised > by > reviewers and also fixes problems discovered during testing. > > This patchset adds support for kernel probes(kprobes), jump probes(jprobes) > and return probes(kretprobes) support for ARM64. > > The kprobes mechanism makes use of software breakpoint and single stepping > support available in the ARM v8 kernel.
I applied this series on v4.6-rc7, and built the sample kprobes. They work fine, unless I throw ftrace into the mix too. I enabled the function_graph tracer, then tried to load the jprobe example module: -------------------------%<------------------------- root@ubuntu:/sys/kernel/debug/tracing# insmod /root/jprobe_example.ko Planted jprobe at ffffff80080c8f20, handler addr ffffff8000bb3000 root@ubuntu:/sys/kernel/debug/tracing# jprobe: clone_flags = 0x1200011, stack_st art = 0x0 stack_size = 0x0 Bad mode in Synchronous Abort handler detected, code 0x86000005 -- IABT (current EL) CPU: 5 PID: 1047 Comm: systemd-udevd Not tainted 4.6.0-rc7+ #4064 Hardware name: ARM Juno development board (r1) (DT) task: ffffffc975948300 ti: ffffffc974e4c000 task.ti: ffffffc974e4c000 PC is at 0x0 LR is at 0x0 pc : [<0000000000000000>] lr : [<0000000000000000>] pstate: 60000145 sp : ffffffc974e4ff00 x29: 0000000001200011 x28: ffffffc974e4c000 x27: ffffff80088d0000 x26: 00000000000000dc x25: 0000000000000120 x24: 0000000000000015 x23: 0000000060000000 x22: 0000007fa1b40e60 x21: 0000007fa1ce70d0 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000a03 x17: 0000007fa1b40d90 x16: ffffff80080c9708 x15: 003b9aca00000000 x14: 0000007fddb7e5c0 x13: 0000007fa1b40e2c x12: 0000000000d00ff0 x11: ffffff8009c4d000 x10: ffffff800920c000 x9 : ffffff8008f5c000 x8 : ffffffc976c06800 x7 : 000000000006daf2 x6 : 0000000000000015 x5 : 0000000000000004 x4 : ffffffc96e8690a0 x3 : 0000001ed7cbab74 x2 : ffffffc96e869000 x1 : 0000000000000000 x0 : 0000000000000000 Internal error: Oops - bad mode: 0 [#1] PREEMPT SMP Modules linked in: jprobe_example CPU: 5 PID: 1047 Comm: systemd-udevd Not tainted 4.6.0-rc7+ #4064 Hardware name: ARM Juno development board (r1) (DT) task: ffffffc975948300 ti: ffffffc974e4c000 task.ti: ffffffc974e4c000 PC is at 0x0 LR is at 0x0 pc : [<0000000000000000>] lr : [<0000000000000000>] pstate: 60000145 sp : ffffffc974e4ff00 x29: 0000000001200011 x28: ffffffc974e4c000 x27: ffffff80088d0000 x26: 00000000000000dc x25: 0000000000000120 x24: 0000000000000015 x23: 0000000060000000 x22: 0000007fa1b40e60 x21: 0000007fa1ce70d0 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000a03 x17: 0000007fa1b40d90 x16: ffffff80080c9708 x15: 003b9aca00000000 x14: 0000007fddb7e5c0 x13: 0000007fa1b40e2c x12: 0000000000d00ff0 x11: ffffff8009c4d000 x10: ffffff800920c000 x9 : ffffff8008f5c000 x8 : ffffffc976c06800 x7 : 000000000006daf2 x6 : 0000000000000015 x5 : 0000000000000004 x4 : ffffffc96e8690a0 x3 : 0000001ed7cbab74 x2 : ffffffc96e869000 x1 : 0000000000000000 x0 : 0000000000000000 Process systemd-udevd (pid: 1047, stack limit = 0xffffffc974e4c020) Stack: (0xffffffc974e4ff00 to 0xffffffc974e50000) ff00: 0000000000000417 0000007fa1ce76f0 00000000000000dc 0000000000000417 ff20: 00000000ffffffff 0000007fddb7ecf8 0000000000000005 ffffffffffffffff ff40: 00000000ff000001 003b9aca00000000 000000555b3868b0 0000007fa1b40d90 ff60: 0000000000000a03 0000007fddb7e5c0 0000000000000000 0000007fddb7e5e0 ff80: 000000555b358000 000000558f56f0e0 0000000000000000 000000558f574f00 ffa0: 000000558f574f00 00000000000004fa 000000558f56f010 0000007fddb7e600 ffc0: 0000007fa1b40e2c 0000007fddb7e5c0 0000007fa1b40e60 0000000060000000 ffe0: 0000000001200011 00000000000000dc 0004000084000200 0800000002000000 Call trace: [< (null)>] (null) Code: bad PC value ---[ end trace 35d24aad799c2941 ]--- -------------------------%<------------------------- Thanks, James