linux 2.2.18pre17 + VM-global -7 = `Negative d_count' oops

Andrea Arcangeli writes ("Re: linux 2.2.18-pre17: "Kernel panic: LRU list corrupted""):

I've been having apparently VM-related `pauses' with 2.2.17 [1], so I thought I'd try 2.2.18pre17 with that patch. The results weren't
good: I get many instances of

Negative d_count (-805538369) for [binary garbage]/<NULL>

followed by an oops. Kernel logfile extract below, uuencoded.

I'm sure I'd be able to reproduce this, but I'd rather not because this is a production system. ver_linux reports:

chiark:linux-2.2.17-chiark> sh scripts/ver_linux
-- Versions installed: (if some fields are empty or looks -- unusual then possibly you have very old versions) Linux chiark 2.2.17 #2 Thu Oct 26 10:57:45 BST 2000 i586 unknown

Kernel modules         2.3.11
Gnu C                  2.95.2
Binutils               2.9.5.0.37
Linux C Library        2.1.3
Dynamic linker         ldd: version 1.9.11
Procps                 2.0.6
Mount                  2.10f
Net-tools              2.05
Kbd                    0.99
Sh-utils               2.0

cat: /proc/modules: No such file or directory
Modules Loaded
chiark:linux-2.2.17-chiark>

I don't know why it says `Kernel modules 2.3.11', since I have disabled kernel modules completely. My CPU is:

processor : 0
vendor_id : AuthenticAMD
cpu family : 5
model : 8
model name : AMD-K6(tm) 3D processor
stepping : 0
cpu MHz : 350.808
cache size : 64 KB
fdiv_bug : no
hlt_bug : no
sep_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr mce cx8 sep mmx 3dnow
bogomips : 699.60

REPORTING-BUGS wanted me to include /proc/scsi/scsi, so here it is:

Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: IBM Model: DCAS-34330 Rev: S65A
Type: Direct-Access ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 02 Lun: 00
Vendor: IBM Model: DCAS-34330 Rev: S65A
Type: Direct-Access ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 04 Lun: 00
Vendor: HP Model: T20 Rev: 3.01
Type: Sequential-Access ANSI SCSI revision: 02
Host: scsi1 Channel: 00 Id: 00 Lun: 00
Vendor: IBM Model: DNES-318350W Rev: SA30
Type: Direct-Access ANSI SCSI revision: 03

It might be relevant that a large part of the system's job is to be a shell account server, and users log in with a variety of mechanisms, most often OpenSSH (Debian 1.2.3-9). I've not had any reports from users about sessions randomly dropping, which I might have expected; however, I did have a number of background cron jobs die in very strange ways suggesting killing of processes at random.

The system as a whole is largely Debian 2.2, and has 256Mb of RAM and about 400Mb of swap. It usually runs with about 50-100Mb of swap used and at a load of somewhere around 1ish during busy periods.

[1] VM lockup problem:

I believe that this is a known problem with the 2.2.x VM ? The symptoms I have are that under reasonably high but not excessive VM and/or disk load, the system will freeze for around 10-15 minutes. Most often this seems to have beeen provoked by a moderately large (20Mb or so) Emacs doing an auto-save during an otherwise-busy time.

During the lockup network packets are processed - pings receive replies, and TCP connection attempts succeed, but there is no evidence of any user-mode executing. After the lockup the system apparently just resumes where it left off. Sometimes afterwards there is a message like `VM: do_try_to_free_pages failed for emacs...' but more often there isn't.

Thanks for your attention,

Ian.

begin 664 chiark-oops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`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`O,C1=(%M? M7V9P=70K-C(O-S)=(%MF<'5T*S(S+S<R72!;;&]A9%]E;&9?8FEN87)Y*S$Y M,S,O,CDW,ET@6V1O7V=E;F5R:6-?9FEL95]R96%D*S$T.3(O,34P-%T@6W)E M861?97AE8RLS-C,O,S@P72!;<V5A<F-H7V)I;F%R>5]H86YD;&5R*S<Q+S$X M.%T@"D]C="R-2Q.#HP-SHP-R!C:&EA<FL@:V5R;F5L.B@("@("@6V1O M7V5X96-V92LT,C4O-#DR72!;<WES7V5X96-V92LT-R\Y,ET@6W-Y<W1E;5]C M86QL*S4R+S4V72*3V-T(#(U(#$X.CW.CW(&-H:6%R:R!K97)N96PZ($-O M9&4Z(&,W(#U(#P(#P(#P(#P(#P(#P(#P(#P(#@S(&,T(#$P(#5B 4(#5E(&,S(#@Y(&8V(#4S(#AB(H`
`
end
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected]
Please read the FAQ at http://www.tux.org/lkml/