Kernel Warnings at fs/debugfs/file.c 90

Kernel Warnings at fs/debugfs/file.c 90

[Venkat Rao Bagalkote]

Greetings!!!


Observing Kernel Warnings on kernel 6.13.0-rc6-next-20250109, while 
running fstests ext4/001.


Traces:

[  433.607975] ------------[ cut here ]------------
[  433.607984] WARNING: CPU: 2 PID: 32051 at fs/debugfs/file.c:90 
__debugfs_file_get+0xcc/0x274
[  433.608002] Modules linked in: ext4 mbcache jbd2 loop dm_mod 
nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet 
nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat 
nf_conntrack bonding nf_defrag_ipv6 nf_defrag_ipv4 tls ip_set rfkill 
nf_tables nfnetlink pseries_rng aes_gcm_p10_crypto crypto_simd 
vmx_crypto xfs sr_mod cdrom sd_mod sg ibmvscsi ibmveth 
scsi_transport_srp fuse
[  433.608065] CPU: 2 UID: 0 PID: 32051 Comm: check Kdump: loaded Not 
tainted 6.13.0-rc6-next-20250109 #1
[  433.608072] Hardware name: IBM,8375-42A POWER9 (architected) 0x4e0202 
0xf000005 of:IBM,FW950.80 (VL950_131) hv:phyp pSeries
[  433.608078] NIP:  c00000000073ce70 LR: c00000000073e69c CTR: 
c00000000073e658
[  433.608083] REGS: c00000000d367720 TRAP: 0700   Not tainted 
(6.13.0-rc6-next-20250109)
[  433.608089] MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 
44248802  XER: 20040000
[  433.608102] CFAR: c00000000073cdec IRQMASK: 0
[  433.608102] GPR00: c00000000073e69c c00000000d3679c0 c000000001644500 
c0000000040a4f80
[  433.608102] GPR04: 0000000000000000 0000000000000007 0000000000040004 
c00000000302a800
[  433.608102] GPR08: 0000000000400000 0000000000000001 0000000000000000 
0000000000002000
[  433.608102] GPR12: c00000000073e658 c00000000f7cdf00 0000000000000000 
0000000000000000
[  433.608102] GPR16: 0000000000000000 0000000000000000 0000000000000000 
0000000000000000
[  433.608102] GPR20: 0000000000000000 0000000000000000 0000000000000000 
0000000000000000
[  433.608102] GPR24: c000000002b92dc8 c0000000953af100 0000000000000002 
c0000000953af140
[  433.608102] GPR28: 0000000000000000 c0000000016148b9 c0000000953af100 
c0000000040a4f80
[  433.608161] NIP [c00000000073ce70] __debugfs_file_get+0xcc/0x274
[  433.608168] LR [c00000000073e69c] open_proxy_open+0x44/0x1c4
[  433.608175] Call Trace:
[  433.608178] [c00000000d367a10] [c0000000007a10b4] 
selinux_file_open+0xdc/0x110
[  433.608186] [c00000000d367aa0] [c00000000060b640] 
do_dentry_open+0x2ec/0x720
[  433.608195] [c00000000d367af0] [c00000000060d370] vfs_open+0x44/0x128
[  433.608201] [c00000000d367b20] [c000000000628e8c] do_open+0x354/0x4fc
[  433.608208] [c00000000d367b80] [c00000000062fc60] path_openat+0x16c/0x344
[  433.608215] [c00000000d367c00] [c00000000062fef4] do_filp_open+0xbc/0x19c
[  433.608222] [c00000000d367d40] [c00000000060da20] 
do_sys_openat2+0x100/0x150
[  433.608229] [c00000000d367db0] [c00000000060de20] sys_openat+0x84/0xe0
[  433.608235] [c00000000d367e10] [c0000000000337e8] 
system_call_exception+0x138/0x330
[  433.608244] [c00000000d367e50] [c00000000000d05c] 
system_call_vectored_common+0x15c/0x2ec
[  433.608252] --- interrupt: 3000 at 0x7fff899ad0c4
[  433.608259] NIP:  00007fff899ad0c4 LR: 00007fff899ad0c4 CTR: 
0000000000000000
[  433.608264] REGS: c00000000d367e80 TRAP: 3000   Not tainted 
(6.13.0-rc6-next-20250109)
[  433.608269] MSR:  800000000280f033 
<SF,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE>  CR: 44248404  XER: 00000000
[  433.608284] IRQMASK: 0
[  433.608284] GPR00: 000000000000011e 00007fffce9eecd0 00007fff89ac7200 
ffffffffffffff9c
[  433.608284] GPR04: 000001003b659d40 0000000000000241 00000000000001b6 
0000000000000000
[  433.608284] GPR08: 0000000000000020 0000000000000000 0000000000000000 
0000000000000000
[  433.608284] GPR12: 0000000000000000 00007fff89beab20 000001003b661f30 
0000000121cd87b8
[  433.608284] GPR16: 0000000121cd89bc 0000000121cd8a50 0000000000000004 
0000000121cd89b8
[  433.608284] GPR20: 0000000000000241 00007fff89be3b30 000001003b659d40 
0000000000000000
[  433.608284] GPR24: 0000000000000241 00007fffce9eee50 0000000000000001 
0000000000000003
[  433.608284] GPR28: 0000000000000000 0000000121cd8260 000001003b5d6480 
00007fffce9eed10
[  433.608342] NIP [00007fff899ad0c4] 0x7fff899ad0c4
[  433.608346] LR [00007fff899ad0c4] 0x7fff899ad0c4
[  433.608349] --- interrupt: 3000
[  433.608352] Code: 38600000 38210050 7c6307b4 eba1ffe8 ebe1fff8 
4e800020 60000000 60000000 7c890034 fb810030 7c9c2378 5529d97e 
<0b090000> 2c240000 41820188 7c0802a6
[  433.608372] ---[ end trace 0000000000000000 ]---


This issue got introduced by the commit: 
f8f25893a477a4da4414c3e40ddd51d77fac9cfc.


Reverting the above commit, test case passes with out warnings.


Regards,

Venkat.

Re: Kernel Warnings at fs/debugfs/file.c 90

[Greg KH]

On Fri, Jan 10, 2025 at 12:14:13PM +0530, Venkat Rao Bagalkote wrote:
> Greetings!!!
> 
> 
> Observing Kernel Warnings on kernel 6.13.0-rc6-next-20250109, while running
> fstests ext4/001.

What is fstests doing in debugfs?

> Traces:
> 
> [  433.607975] ------------[ cut here ]------------
> [  433.607984] WARNING: CPU: 2 PID: 32051 at fs/debugfs/file.c:90
> __debugfs_file_get+0xcc/0x274

This is an assertion firing, Johannes, any ideas?

thanks,

greg k-h

Re: Kernel Warnings at fs/debugfs/file.c 90

[Greg KH]

On Fri, Jan 10, 2025 at 09:34:52AM +0100, Greg KH wrote:
> On Fri, Jan 10, 2025 at 12:14:13PM +0530, Venkat Rao Bagalkote wrote:
> > Greetings!!!
> > 
> > 
> > Observing Kernel Warnings on kernel 6.13.0-rc6-next-20250109, while running
> > fstests ext4/001.
> 
> What is fstests doing in debugfs?
> 
> > Traces:
> > 
> > [  433.607975] ------------[ cut here ]------------
> > [  433.607984] WARNING: CPU: 2 PID: 32051 at fs/debugfs/file.c:90
> > __debugfs_file_get+0xcc/0x274
> 
> This is an assertion firing, Johannes, any ideas?

Oh nevermind, you already sent me a fix for this, thanks!

greg k-h