On Fri, Jan 18, 2019 at 6:45 PM Zenghui Yu <zenghuiyu96@xxxxxxxxx> wrote: > > Hi, All! > > I compiled the latest kernel and installed it on my old laptop (Hardware name: > Hewlett-Packard HP ProBook 440 G2/2247, BIOS M74 Ver. 01.02 06/17/2014). But > when I tried to enable function tracer via debugfs, the system went _hung_! > Compared with the last kernel compiling process, the only change I have made > is that I enabled KASAN configuration this time. > > Reproducing this issue is simple as below: > > 0. `uname -a` shows: > Linux ubuntuu 5.0.0-rc2+ #9 SMP Fri Jan 18 03:04:01 CST 2019 > x86_64 x86_64 x86_64 GNU/Linux > > 1. `make menuconfig` to enable KASAN configuration: > Kernel hacking ---> Memory Debugging ---> > KASAN: runtime memory debugger > > compile, install, reboot, then `dmesg | grep kasan` shows: > [ 0.342882] kasan: KernelAddressSanitizer initialized > > 2. enable function tracer > `echo function > /sys/kernel/debug/tracing/current_tracer` > (then my poor laptop was locked and didn't respond to me ...) > > What's more, enabling function graph tracer will suffer from the same problem. > I have no idea about what wrong thing had happened inside kernel -- > about ftrace, > or about KASAN? So I report it to you and waiting for your solution! > > I have provided my *.config* file as attachment for those who're interested in > this issue. But sorry for that I can't provide any useful call trace > because the > system went down so quickly. > > P.S. I'm a newcomer for KASAN. If any mis-configuration or > mis-understand, please > fix me up and let me know :). Hi Zenghui, I've tried to reproduce this, but kernel crashes during boot with this config for me. I am commit 2339e91d0e6609e17943a0ab3c3c8c4044760c05, the config is basically yours but updated for newer compiler and with builtin modules: https://gist.githubusercontent.com/dvyukov/9af234617749aa4eada67ba8c2e4f46c/raw/d0e09ddf255962313a82bb552c3fc0d832fa6844/gistfile1.txt TITLE: WARNING in note_page MAINTAINERS: [dave.hansen@xxxxxxxxxxxxxxx luto@xxxxxxxxxx peterz@xxxxxxxxxxxxx tglx@xxxxxxxxxxxxx mingo@xxxxxxxxxx bp@xxxxxxxxx hpa@xxxxxxxxx x86@xxxxxxxxxx linux-kernel@xxxxxxxxxxxxxxx] ------------[ cut here ]------------ x86/mm: Found insecure W+X mapping at address native_usergs_sysret64+0x0/0x10 WARNING: CPU: 3 PID: 1 at arch/x86/mm/dump_pagetables.c:263 note_wx arch/x86/mm/dump_pagetables.c:262 [inline] WARNING: CPU: 3 PID: 1 at arch/x86/mm/dump_pagetables.c:263 note_page+0x800/0xaf0 arch/x86/mm/dump_pagetables.c:302 Kernel panic - not syncing: panic_on_warn set ... CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc2+ #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x7b/0xb5 lib/dump_stack.c:113 panic+0x18e/0x351 kernel/panic.c:214 __warn+0x13c/0x140 kernel/panic.c:571 report_bug+0xd7/0x140 lib/bug.c:186 fixup_bug.part.11+0x2d/0x60 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/include/asm/paravirt.h:776 [inline] do_error_trap+0xb6/0xc0 arch/x86/kernel/traps.c:271 do_invalid_op+0x3b/0x50 arch/x86/kernel/traps.c:290 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 RIP: 0010:note_wx arch/x86/mm/dump_pagetables.c:262 [inline] RIP: 0010:note_page+0x800/0xaf0 arch/x86/mm/dump_pagetables.c:302 Code: 4d 32 00 4c 89 7b 28 48 c7 43 30 00 00 00 00 e9 46 fc ff ff 4c 89 ee 48 c7 c7 a0 35 c5 ae c6 05 02 81 1e 02 01 e8 50 93 01 00 <0f> 0b 48 8b 7d 90 e8 75 4c 32 00 48 8b 43 20 48 89 45 c8 e9 72 f9 RSP: 0000:ffff88805d5c7d18 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88805d5c7e58 RCX: ffffffffae7f11db RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000246 RBP: ffff88805d5c7da0 R08: ffffed100bab8f5c R09: ffffed100bab8f5c R10: 0000000000000002 R11: ffffed100bab8f5c R12: 0000000000000000 R13: ffffffffae800000 R14: 0000000000000004 R15: 0000000000000000 walk_pmd_level arch/x86/mm/dump_pagetables.c:428 [inline] walk_pud_level arch/x86/mm/dump_pagetables.c:459 [inline] walk_p4d_level arch/x86/mm/dump_pagetables.c:484 [inline] ptdump_walk_pgd_level_core+0x566/0x6e0 arch/x86/mm/dump_pagetables.c:552 ptdump_walk_user_pgd_level_checkwx+0x4e/0x50 arch/x86/mm/dump_pagetables.c:600 pti_finalize+0x27/0xaf arch/x86/mm/pti.c:682 kernel_init+0x3e/0x130 init/main.c:1066 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352 Kernel Offset: 0x2c800000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Rebooting in 86400 seconds..
