On Mon, Dec 18, 2023 at 10:16:23PM +0900, Masami Hiramatsu (Google) wrote: > From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> > > This allows fprobes to be available with CONFIG_DYNAMIC_FTRACE_WITH_ARGS > instead of CONFIG_DYNAMIC_FTRACE_WITH_REGS, then we can enable fprobe > on arm64. > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> > Acked-by: Florent Revest <revest@xxxxxxxxxxxx> this change breaks kprobe multi bpf tests (crash below), which are partially fixed by [1] later on, but I think we have to keep bisecting crash free it looks like the rethook will get wrong pointer.. I'm still trying to digest the whole thing, so I might have some updates later ;-) jirka [1] fprobe: Rewrite fprobe on function-graph tracer --- Dec 19 13:50:04 qemu kernel: BUG: kernel NULL pointer dereference, address: 0000000000000098 Dec 19 13:50:04 qemu kernel: #PF: supervisor read access in kernel mode Dec 19 13:50:04 qemu kernel: #PF: error_code(0x0000) - not-present page Dec 19 13:50:04 qemu kernel: PGD 10955f067 P4D 10955f067 PUD 103113067 PMD 0 Dec 19 13:50:04 qemu kernel: Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN NOPTI Dec 19 13:50:04 qemu kernel: CPU: 1 PID: 747 Comm: test_progs Tainted: G B OE 6.7.0-rc3+ #194 85bc8297edbc7f21acfc743dabbd52cac073a6bf Dec 19 13:50:04 qemu kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38 04/01/2014 Dec 19 13:50:04 qemu kernel: RIP: 0010:arch_rethook_prepare+0x18/0x60 Dec 19 13:50:04 qemu kernel: Code: 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 55 41 54 55 48 89 f5 53 48 89 fb 48 8d be 98 00 00 00 e8 68 8f 59 > Dec 19 13:50:04 qemu kernel: RSP: 0018:ffff888125f97a88 EFLAGS: 00010286 Dec 19 13:50:04 qemu kernel: RAX: 0000000000000001 RBX: ffff88818a231410 RCX: ffffffff812190b6 Dec 19 13:50:04 qemu kernel: RDX: fffffbfff0c42e95 RSI: 0000000000000008 RDI: ffffffff862174a0 Dec 19 13:50:04 qemu kernel: RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff0c42e94 Dec 19 13:50:04 qemu kernel: R10: ffffffff862174a7 R11: 0000000000000000 R12: ffff88818a231420 Dec 19 13:50:04 qemu kernel: R13: ffffffff8283ee8e R14: ffff88818a231410 R15: fffffffffffffff7 Dec 19 13:50:04 qemu kernel: FS: 00007ff8a16cfd00(0000) GS:ffff88842c600000(0000) knlGS:0000000000000000 Dec 19 13:50:05 qemu kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Dec 19 13:50:05 qemu kernel: CR2: 0000000000000098 CR3: 000000010633c005 CR4: 0000000000770ef0 Dec 19 13:50:05 qemu kernel: PKRU: 55555554 Dec 19 13:50:05 qemu kernel: Call Trace: Dec 19 13:50:05 qemu kernel: <TASK> Dec 19 13:50:05 qemu kernel: ? __die+0x1f/0x70 Dec 19 13:50:05 qemu kernel: ? page_fault_oops+0x215/0x620 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: ? __pfx_page_fault_oops+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? asm_sysvec_apic_timer_interrupt+0x16/0x20 Dec 19 13:50:05 qemu kernel: ? do_user_addr_fault+0x4b3/0x910 Dec 19 13:50:05 qemu kernel: ? exc_page_fault+0x77/0x130 Dec 19 13:50:05 qemu kernel: ? asm_exc_page_fault+0x22/0x30 Dec 19 13:50:05 qemu kernel: ? bpf_prog_test_run_tracing+0x1ce/0x2d0 Dec 19 13:50:05 qemu kernel: ? add_taint+0x26/0x90 Dec 19 13:50:05 qemu kernel: ? arch_rethook_prepare+0x18/0x60 Dec 19 13:50:05 qemu kernel: ? arch_rethook_prepare+0x18/0x60 Dec 19 13:50:05 qemu kernel: ? bpf_prog_test_run_tracing+0x1ce/0x2d0 Dec 19 13:50:05 qemu kernel: rethook_hook+0x1e/0x50 Dec 19 13:50:05 qemu kernel: ? __pfx_bpf_fentry_test1+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? bpf_prog_test_run_tracing+0x1ce/0x2d0 Dec 19 13:50:05 qemu kernel: fprobe_handler+0x1ca/0x350 Dec 19 13:50:05 qemu kernel: ? __pfx_bpf_fentry_test1+0x10/0x10 Dec 19 13:50:05 qemu kernel: arch_ftrace_ops_list_func+0x143/0x2e0 Dec 19 13:50:05 qemu kernel: ? bpf_prog_test_run_tracing+0x1ce/0x2d0 Dec 19 13:50:05 qemu kernel: ftrace_call+0x5/0x44 Dec 19 13:50:05 qemu kernel: ? __pfx_lock_release+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: ? bpf_prog_test_run_tracing+0xcd/0x2d0 Dec 19 13:50:05 qemu kernel: ? bpf_fentry_test1+0x5/0x10 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: bpf_fentry_test1+0x5/0x10 Dec 19 13:50:05 qemu kernel: bpf_prog_test_run_tracing+0x1ce/0x2d0 Dec 19 13:50:05 qemu kernel: ? __pfx_lock_release+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? __pfx_bpf_prog_test_run_tracing+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? __pfx_lock_release+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? __fget_light+0xdf/0x100 Dec 19 13:50:05 qemu kernel: ? __bpf_prog_get+0x107/0x150 Dec 19 13:50:05 qemu kernel: __sys_bpf+0x552/0x2ef0 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: ? __pfx___sys_bpf+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? __pfx_lock_release+0x10/0x10 Dec 19 13:50:05 qemu kernel: ? vfs_write+0x1fa/0x740 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: ? rcu_is_watching+0x34/0x60 Dec 19 13:50:05 qemu kernel: ? lockdep_hardirqs_on_prepare+0xe/0x250 Dec 19 13:50:05 qemu kernel: ? seqcount_lockdep_reader_access.constprop.0+0x105/0x120 Dec 19 13:50:05 qemu kernel: ? seqcount_lockdep_reader_access.constprop.0+0xb2/0x120 Dec 19 13:50:05 qemu kernel: __x64_sys_bpf+0x44/0x60 Dec 19 13:50:05 qemu kernel: do_syscall_64+0x3f/0xf0 Dec 19 13:50:05 qemu kernel: entry_SYSCALL_64_after_hwframe+0x6e/0x76 Dec 19 13:50:05 qemu kernel: RIP: 0033:0x7ff8a1897b4d Dec 19 13:50:05 qemu kernel: Code: c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f > Dec 19 13:50:05 qemu kernel: RSP: 002b:00007fff34f7d158 EFLAGS: 00000206 ORIG_RAX: 0000000000000141 Dec 19 13:50:05 qemu kernel: RAX: ffffffffffffffda RBX: 00007ff8a19aa000 RCX: 00007ff8a1897b4d Dec 19 13:50:05 qemu kernel: RDX: 0000000000000050 RSI: 00007fff34f7d190 RDI: 000000000000000a Dec 19 13:50:05 qemu kernel: RBP: 00007fff34f7d170 R08: 0000000000000000 R09: 00007fff34f7d190 Dec 19 13:50:05 qemu kernel: R10: 0000000000000064 R11: 0000000000000206 R12: 0000000000000004 Dec 19 13:50:05 qemu kernel: R13: 0000000000000000 R14: 00007ff8a19df000 R15: 0000000000e56db0 Dec 19 13:50:05 qemu kernel: </TASK> Dec 19 13:50:05 qemu kernel: Modules linked in: bpf_testmod(OE) intel_rapl_msr intel_rapl_common crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_inte> Dec 19 13:50:05 qemu kernel: CR2: 0000000000000098 Dec 19 13:50:05 qemu kernel: ---[ end trace 0000000000000000 ]---
