Re: XFS DMAPI implementation

[Aurelien DEGREMONT - Stagiaire <degremont@xxxxxxxxxxx>]

Dean Roehrich a écrit :
> It's all of the 2.6.10 kernel.  Is there something else you want?

No, in fact, i would like less features (no kdb, but it's not really 
important). The best solution will be to have a dmapi patch which could 
be used to build our own version of Kernel 2.6.10 tree.
Your CVS tree is not so bad, we just don't know, because its a cvs 
repository, which code is stable, which modification is not. 
Unfortunately, we're dependent of your kernel tree...

> It's used in production environments.  We don't make release snapshots for
> DMAPI.  I suppose we could, but there's never been a need to do so.

Presently, if we want to use dmapi, we must use it with your kernel tree .

> Are you using the kernel tree you got from oss.sgi.com?  I'd like to know what
> you're seeing.

In fact, i try to extract a kernel patch from your cvs tree against 
kernel 2.6 without the kdb patch, only the xfs/dmapi modification. Maybe 
 i missed something.

To reproduced it, i've just to
- load the dmapi module,
(DO NOT load the xfs module)
- unload the dmapi module. => modprobe segfault.
The module is still considered loaded (still in lsmod list), but not 
usable (the symbols aren't available).


OS : Red Hat Enterprise Linux AS release 3.90 (Nahant)
Arch : Itanium

Here is the kernel messages :
=======================================================
DMAPI assertion failed: dm_fsys_map, file: fs/dmapi/dmapi_mountinfo.c, 
line: 343
kernel BUG at fs/dmapi/dmapi_port.h:72!
modprobe[6149]: bugcheck! 0 [1]
Modules linked in: dmapi parport_pc lp parport autofs4 nfs lockd sunrpc 
vfat fat video button joydev md5 ipv6 uhci_hcd ehci_hcd

Pid: 6149, CPU 2, comm:             modprobe
psr : 0000101008126010 ifs : 800000000000030a ip  : [<a000000200228d50>] 
   Not tainted
ip is at dm_fsys_vector_free+0x130/0x160 [dmapi]
unat: 0000000000000000 pfs : 000000000000030a rsc : 0000000000000003
rnat: 0000000000000000 bsps: 0000000000000000 pr  : 0000000005569959
ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c8a70033f
csd : 0000000000000000 ssd : 0000000000000000
b0  : a000000200228d50 b6  : a000000100322600 b7  : a000000100174660
f6  : 0fffbccccccccc8c00000 f7  : 0ffdc8dc0000000000000
f8  : 10001e000000000000000 f9  : 10002a000000000000000
f10 : 0fffeb33333332fa80000 f11 : 1003e0000000000000000
r1  : a000000100a6e4f0 r2  : 0000000000003a14 r3  : a00000010086ea90
r8  : 0000000000000028 r9  : a0000001007b7b40 r10 : a0000001007b7b38
r11 : a00000010086e700 r12 : e0000004c9f3fdc0 r13 : e0000004c9f38000
r14 : 0000000000004000 r15 : a00000010080a7d8 r16 : 0000000000000001
r17 : a000000100884430 r18 : e0000003ffdc2680 r19 : a0000001008ea9c0
r20 : a0000001008ea990 r21 : a0000001008ea990 r22 : 0000000000000034
r23 : a0000001008bae09 r24 : 0000000000003a69 r25 : 0000000000003a69
r26 : 000000000000003e r27 : 0000001008126010 r28 : a0000001008bae0a
r29 : 0000000000003a6a r30 : 0000000000000000 r31 : a000000100883980

Call Trace:
 [<a000000100012320>] show_stack+0x80/0xa0
                                sp=e0000004c9f3f970 bsp=e0000004c9f38fa8
 [<a000000100012c30>] show_regs+0x890/0x8c0
                                sp=e0000004c9f3fb40 bsp=e0000004c9f38f60
 [<a0000001000386b0>] die+0x150/0x200
                                sp=e0000004c9f3fb60 bsp=e0000004c9f38f20
 [<a0000001000387a0>] die_if_kernel+0x40/0x60
                                sp=e0000004c9f3fb60 bsp=e0000004c9f38ef0
 [<a000000100038bf0>] ia64_bad_break+0x430/0x4c0
                                sp=e0000004c9f3fb60 bsp=e0000004c9f38ec8
 [<a00000010000ade0>] ia64_leave_kernel+0x0/0x260
                                sp=e0000004c9f3fbf0 bsp=e0000004c9f38ec8
 [<a000000200228d50>] dm_fsys_vector_free+0x130/0x160 [dmapi]
                                sp=e0000004c9f3fdc0 bsp=e0000004c9f38e78
 [<a000000200237960>] cleanup_module+0x120/0x140 [dmapi]
                                sp=e0000004c9f3fdc0 bsp=e0000004c9f38e60
 [<a0000001000ccee0>] sys_delete_module+0x320/0x640
                                sp=e0000004c9f3fdc0 bsp=e0000004c9f38de0
 [<a00000010000ac60>] ia64_ret_from_syscall+0x0/0x20
                                sp=e0000004c9f3fe30 bsp=e0000004c9f38de0
 [<a000000000010640>] 0xa000000000010640
                                sp=e0000004c9f40000 bsp=e0000004c9f38de0



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