Good Morning,
I have been trying to track down a bug that has been causing my Tegra3
device to reboot while compiling.
I finally managed to catch the offender, the details are below:
The offending code is a triggered bug in dget_parent, the code is:
rcu_read_unlock();
BUG_ON(!ret->d_lockref.count);
ret->d_lockref.count++;
Thanks,
Peter Geis
[ 6399.677492] ------------[ cut here ]------------
[ 6399.682136] kernel BUG at fs/dcache.c:899!
[ 6399.686228] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
[ 6399.692072] Modules linked in: cpufreq_userspace cpufreq_powersave
cpufreq_conservative snd_soc_tegr4
[ 6399.732443] CPU: 1 PID: 18614 Comm: fixdep Not tainted
4.18.0-rc4-next-20180710-00059-g52ccdc95b9c6 2
[ 6399.741927] Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
[ 6399.748220] PC is at dget_parent+0xac/0xb0
[ 6399.752315] LR is at dget_parent+0x78/0xb0
[ 6399.756416] pc : [<c033a5d4>] lr : [<c033a5a0>] psr: 600d0013
[ 6399.762675] sp : d52abcf0 ip : d52abcf0 fp : d52abd0c
[ 6399.767908] r10: c1004dc8 r9 : c12ed6c0 r8 : c12ed6c0
[ 6399.773144] r7 : ccf55518 r6 : ccf554c8 r5 : ccf55550 r4 : ccf554c8
[ 6399.779662] r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 : 00000000
[ 6399.786193] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM
Segment none
[ 6399.793330] Control: 10c5387d Table: ab03c04a DAC: 00000051
[ 6399.799092] Process fixdep (pid: 18614, stack limit = 0x51488b23)
[ 6399.805203] Stack: (0xd52abcf0 to 0xd52ac000)
[ 6399.809558] bce0: c12ed6c0
ed626e30 ed626e30 ecc6c000
[ 6399.817746] bd00: d52abd34 d52abd10 c037e92c c033a534 d52abd48
d52abd60 00000002 c1004dc8
[ 6399.825934] bd20: ecc6d800 ed626e30 d52abdc4 d52abd38 c03cc0fc
c037e8f8 e3b07ce7 00000009
[ 6399.834123] bd40: d52abd9c d52abd50 c032b938 c032c4c0 ed624ee8
00000081 00000000 2f2f2f2f
[ 6399.842290] bd60: 00000000 e3b07ce7 d52abd9c d52abd78 c032c4c0
c032c2e4 d52abe90 c032b630
[ 6399.850482] bd80: d52abe98 a833ed19 d52abdc8 c001402d c12ed6c8
aaf19945 c12ed6c8 c12ed6c0
[ 6399.858668] bda0: ed626e30 c12ed6c8 c03cc0a0 00020000 c12ed6c0
c1004dc8 d52abdec d52abdc8
[ 6399.866857] bdc0: c031ab54 c03cc0ac d52abe90 00000000 00000000
00000000 00020000 c12ed6c0
[ 6399.875053] bde0: d52abdfc d52abdf0 c031bec0 c031a990 d52abe8c
d52abe00 c032f3dc c031be90
[ 6399.883251] be00: efdc7e90 c12ed780 d52abe94 d52abe18 c02a2d8c
c033f1bc c0d18774 aaf19945
[ 6399.891420] be20: 00000165 006000c0 ffffe000 00000041 c1004dc8
00000000 00000004 ccf554c8
[ 6399.899606] be40: 00000002 ed626e30 ee7a8b10 ccf55550 00000165
00000000 00000165 aaf19945
[ 6399.907795] be60: c0324ac8 c1004dc8 c1004dc8 d52abe90 d52abf50
00000001 d52aa000 00000142
[ 6399.915984] be80: d52abf44 d52abe90 c033169c c032f0b0 ee7a8b10
ccf55550 a833ed19 0000000f
[ 6399.924174] bea0: c001402d d52abeb0 00000000 c05590a4 ed626e30
00000101 00000002 00005084
[ 6399.932342] bec0: 00000000 00000000 00000000 d52abed0 ffffff9c
00000003 e751d800 c0a0da8c
[ 6399.940532] bee0: d52abefc d52abef0 c0a0da8c c0161d1c d52abf34
d52abf00 c0340ea8 c0a0da64
[ 6399.948726] bf00: c0014000 00000000 00020000 00020000 ffffff9c
ffffff9c c0014000 aaf19945
[ 6399.956920] bf20: d52aa000 00000003 c1004dc8 ffffff9c c0014000
fffff000 d52abf94 d52abf48
[ 6399.965105] bf40: c031c20c c0331624 d52abf64 d52abf58 00020000
c0160000 00000004 00000100
[ 6399.973290] bf60: 00000001 aaf19945 c0101204 b6fc2000 b6fee968
b6fee968 00000142 c0101204
[ 6399.981458] bf80: d52aa000 00000142 d52abfa4 d52abf98 c031c2d8
c031c088 00000000 d52abfa8
[ 6399.989644] bfa0: c0101000 c031c2c8 b6fc2000 b6fee968 ffffff9c
00a76b09 00020000 00000000
[ 6399.997844] bfc0: b6fc2000 b6fee968 b6fee968 00000142 00a76b34
0000002c 00000020 00a78f50
[ 6400.006037] bfe0: 00000142 becd9210 b6f5a709 b6ee5206 200d0030
ffffff9c 00000000 00000000
[ 6400.014257] [<c033a5d4>] (dget_parent) from [<c037e92c>]
(fscrypt_file_open+0x40/0xe0)
[ 6400.022183] [<c037e92c>] (fscrypt_file_open) from [<c03cc0fc>]
(ext4_file_open+0x5c/0x1dc)
[ 6400.030520] [<c03cc0fc>] (ext4_file_open) from [<c031ab54>]
(do_dentry_open.constprop.4+0x1d0/0x3d0)
[ 6400.039715] [<c031ab54>] (do_dentry_open.constprop.4) from
[<c031bec0>] (vfs_open+0x3c/0x40)
[ 6400.048200] [<c031bec0>] (vfs_open) from [<c032f3dc>]
(path_openat+0x338/0x139c)
[ 6400.055624] [<c032f3dc>] (path_openat) from [<c033169c>]
(do_filp_open+0x84/0xf0)
[ 6400.063138] [<c033169c>] (do_filp_open) from [<c031c20c>]
(do_sys_open+0x190/0x214)
[ 6400.070825] [<c031c20c>] (do_sys_open) from [<c031c2d8>]
(sys_openat+0x1c/0x20)
[ 6400.078202] [<c031c2d8>] (sys_openat) from [<c0101000>]
(ret_fast_syscall+0x0/0x54)
[ 6400.085890] Exception stack(0xd52abfa8 to 0xd52abff0)
[ 6400.090970] bfa0: b6fc2000 b6fee968 ffffff9c
00a76b09 00020000 00000000
[ 6400.099150] bfc0: b6fc2000 b6fee968 b6fee968 00000142 00a76b34
0000002c 00000020 00a78f50
[ 6400.107313] bfe0: 00000142 becd9210 b6f5a709 b6ee5206
[ 6400.112385] Code: e1a00007 eb1b4d22 ebf9dba1 eaffffe9 (e7f001f2)
[ 6400.118529] ---[ end trace 8a2c7cc18f454ac3 ]---
