Fwd: Re: Fwd: Mounting an lvm-backed device via FUSE: 100% cpu usage and memory exhaustion.

[Vladimir 'φ-coder/phcoder' Serbinenko]

-------- Original Message --------
Subject: 	Re: Fwd: Mounting an lvm-backed device via FUSE: 100% cpu 
usage and memory exhaustion.
Date:   Wed, 14 Dec 2011 13:03:06 +0100
From:   Paolo Pisati <address@hidden>
To:     Vladimir 'φ-coder/phcoder' Serbinenko <address@hidden>



On 12/13/2011 01:13 AM, Vladimir 'φ-coder/phcoder' Serbinenko wrote:
>  So first thing: I don't accept bugreports by private mail. Use
>  grub-devel or bug-grub.
>  Second thing: debian grub mount is based on old version of branch,
>  please use upstream.
>  Third thing I will need the output of grub-fstest /dev/sdXY ls -- -l and
>  a backtrace of a hang (of a version with symbols)

address@hidden grub]$ bzr log -l 1 | grep revno
revno: 3658

address@hidden grub]$ sudo ./grub-fstest /dev/sdd1 ls -- -l
Device loop0: Filesystem type ufs2 - Last modification time 2009-06-21
10:52:41 Sunday, UUID 49bcd83e59408510 - Total size 1953520002 sectors
Device host: Filesystem type hostfs - Total size 0 sectors
Device lvm/storage-storage: Filesystem type ext2 - Last modification
time 2011-12-14 08:06:06 Wednesday, UUID
b6df38ad-605c-4b9a-965c-71b8f4012684 - Total size 1953513472 sectors

ufs2? where does it come from?

address@hidden ~]$ sudo fdisk -l /dev/sdd

Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xa7591a3d

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1              63  1953520064   976760001   8e  Linux LVM

backtrace:


address@hidden grub]# ./grub-mount /dev/sdd1 /media/
address@hidden grub]# ps -auxwww | grep grub-mount
Warning: bad ps syntax, perhaps a bogus '-'? See
http://procps.sf.net/faq.html
root     15214  0.0  0.0  29660  1332 ?        Ss   12:39   0:00
./grub-mount /dev/sdd1 /media/
root     15216  0.0  0.0  14560   888 pts/2    S+   12:39   0:00 grep
grub-mount
address@hidden grub]# gdb ./grub-mount 15214

...

grub_memmove (dest=0xcaadc0, src=0xbf9dd0, n=24244) at
grub-core/kern/misc.c:61
61              *--d = *--s;
(gdb) bt
#0  grub_memmove (dest=0xcaadc0, src=0xbf9dd0, n=24244) at
grub-core/kern/misc.c:61
#1  0x0000000000451ee3 in grub_memcpy (dest=0xcaadc0, src=0xbf9dd0,
n=32768) at ./include/grub/misc.h:62
#2  0x0000000000452eda in grub_disk_read (disk=0xb99c90,
sector=1953519424, offset=0, size=33792, buf=0xcaadc0) at
grub-core/kern/disk.c:550
#3  0x000000000043a21d in scan_disk (dev=0xb99ce0, data=0xb78b50,
original=1, inserted=0x7fff68b7a294) at grub-core/fs/zfs/zfs.c:917
#4  0x0000000000440d95 in zfs_mount (dev=0xb99ce0) at
grub-core/fs/zfs/zfs.c:3299
#5  0x0000000000441ee1 in grub_zfs_dir (device=0xb99ce0, path=0x474e14
"/") at grub-core/fs/zfs/zfs.c:3790
#6  0x0000000000454cc3 in grub_fs_probe (device=0xb99ce0) at
grub-core/kern/fs.c:55
#7  0x0000000000454998 in grub_file_open (name=0xb99c70 "//") at
grub-core/kern/file.c:96
#8  0x00000000004033e6 in call_fill (filename=0x7fff68b7a8e0 "",
info=0x7fff68b7a920) at util/grub-mount.c:292
#9  0x00000000004344dc in grub_ufs_dir (device=0xb77740, path=0xb776e0
"/", hook=0x7fff68b7aac8) at grub-core/fs/ufs.c:640
#10 0x000000000040358d in fuse_readdir (buf=0xb77660,
fill=0x7ff9bd932a05<fill_dir>, off=0, fi=0x7fff68b7ac40) at
util/grub-mount.c:314
#11 0x00007ff9bd92eaba in fuse_fs_readdir (fs=0xb98f20, path=0xb99450
"/", buf=0xb77660, filler=0x7ff9bd932a05<fill_dir>, off=0,
fi=0x7fff68b7ac40) at fuse.c:1401
#12 0x00007ff9bd932dc3 in readdir_fill (f=0xb98e20, req=0xb775d0, ino=1,
size=4096, off=0, dh=0xb77660, fi=0x7fff68b7ac40) at fuse.c:2754
#13 0x00007ff9bd932ed7 in fuse_lib_readdir (req=0xb775d0, ino=1,
size=4096, off=0, llfi=0x7fff68b7acb0) at fuse.c:2780
#14 0x00007ff9bd938a25 in do_readdir (req=0xb775d0, nodeid=1,
inarg=0x7ff9bdf5b038) at fuse_lowlevel.c:846
#15 0x00007ff9bd93a3dd in fuse_ll_process (data=0xb99090,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_lowlevel.c:1514
#16 0x00007ff9bd93c3c1 in fuse_session_process (se=0xb77700,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_session.c:80
#17 0x00007ff9bd935ffa in fuse_session_loop (se=0xb77700) at fuse_loop.c:33
#18 0x00007ff9bd934c05 in fuse_loop (f=0xb98e20) at fuse.c:3436
#19 0x00007ff9bd93dff1 in fuse_main_common (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0, compat=0) at helper.c:330
#20 0x00007ff9bd93e059 in fuse_main_real (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0) at helper.c:342
#21 0x00000000004037c3 in fuse_init () at util/grub-mount.c:384
#22 0x0000000000403f2e in main (argc=3, argv=0x7fff68b7b058) at
util/grub-mount.c:558
(gdb) c
Continuing.
^C
Program received signal SIGINT, Interrupt.
0x0000000000455552 in grub_memmove (dest=0xcb31c0, src=0xc12200,
n=23108) at grub-core/kern/misc.c:61
61              *--d = *--s;
(gdb) bt
#0  0x0000000000455552 in grub_memmove (dest=0xcb31c0, src=0xc12200,
n=23108) at grub-core/kern/misc.c:61
#1  0x0000000000451ee3 in grub_memcpy (dest=0xcb31c0, src=0xc12200,
n=31744) at ./include/grub/misc.h:62
#2  0x000000000045298f in grub_disk_read_small (disk=0xb99c90,
sector=1953519744, offset=1024, size=31744, buf=0xcb31c0) at
grub-core/kern/disk.c:414
#3  0x0000000000452dcf in grub_disk_read (disk=0xb99c90,
sector=1953519746, offset=0, size=131072, buf=0xcb31c0) at
grub-core/kern/disk.c:518
#4  0x000000000043a21d in scan_disk (dev=0xb99c50, data=0xb78b50,
original=1, inserted=0x7fff68b7a294) at grub-core/fs/zfs/zfs.c:917
#5  0x0000000000440d95 in zfs_mount (dev=0xb99c50) at
grub-core/fs/zfs/zfs.c:3299
#6  0x0000000000441ee1 in grub_zfs_dir (device=0xb99c50, path=0x474e14
"/") at grub-core/fs/zfs/zfs.c:3790
#7  0x0000000000454cc3 in grub_fs_probe (device=0xb99c50) at
grub-core/kern/fs.c:55
#8  0x0000000000454998 in grub_file_open (name=0xb99ce0 "//") at
grub-core/kern/file.c:96
#9  0x00000000004033e6 in call_fill (filename=0x7fff68b7a8e0 "",
info=0x7fff68b7a920) at util/grub-mount.c:292
#10 0x00000000004344dc in grub_ufs_dir (device=0xb77740, path=0xb776e0
"/", hook=0x7fff68b7aac8) at grub-core/fs/ufs.c:640
#11 0x000000000040358d in fuse_readdir (buf=0xb77660,
fill=0x7ff9bd932a05<fill_dir>, off=0, fi=0x7fff68b7ac40) at
util/grub-mount.c:314
#12 0x00007ff9bd92eaba in fuse_fs_readdir (fs=0xb98f20, path=0xb99450
"/", buf=0xb77660, filler=0x7ff9bd932a05<fill_dir>, off=0,
fi=0x7fff68b7ac40) at fuse.c:1401
#13 0x00007ff9bd932dc3 in readdir_fill (f=0xb98e20, req=0xb775d0, ino=1,
size=4096, off=0, dh=0xb77660, fi=0x7fff68b7ac40) at fuse.c:2754
#14 0x00007ff9bd932ed7 in fuse_lib_readdir (req=0xb775d0, ino=1,
size=4096, off=0, llfi=0x7fff68b7acb0) at fuse.c:2780
#15 0x00007ff9bd938a25 in do_readdir (req=0xb775d0, nodeid=1,
inarg=0x7ff9bdf5b038) at fuse_lowlevel.c:846
#16 0x00007ff9bd93a3dd in fuse_ll_process (data=0xb99090,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_lowlevel.c:1514
#17 0x00007ff9bd93c3c1 in fuse_session_process (se=0xb77700,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_session.c:80
#18 0x00007ff9bd935ffa in fuse_session_loop (se=0xb77700) at fuse_loop.c:33
#19 0x00007ff9bd934c05 in fuse_loop (f=0xb98e20) at fuse.c:3436
#20 0x00007ff9bd93dff1 in fuse_main_common (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0, compat=0) at helper.c:330
#21 0x00007ff9bd93e059 in fuse_main_real (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0) at helper.c:342
#22 0x00000000004037c3 in fuse_init () at util/grub-mount.c:384
#23 0x0000000000403f2e in main (argc=3, argv=0x7fff68b7b058) at
util/grub-mount.c:558
(gdb) c
Continuing.
...
^C
Program received signal SIGINT, Interrupt.
0x0000000000455555 in grub_memmove (dest=0xc8adb0, src=0xbf9dd0, n=9575)
at grub-core/kern/misc.c:61
61              *--d = *--s;
(gdb) bt
#0  0x0000000000455555 in grub_memmove (dest=0xc8adb0, src=0xbf9dd0,
n=9575) at grub-core/kern/misc.c:61
#1  0x0000000000451ee3 in grub_memcpy (dest=0xc8adb0, src=0xbf9dd0,
n=32768) at ./include/grub/misc.h:62
#2  0x0000000000452eda in grub_disk_read (disk=0xb99c90,
sector=1953519424, offset=0, size=33792, buf=0xc8adb0) at
grub-core/kern/disk.c:550
#3  0x000000000043a21d in scan_disk (dev=0xb99c70, data=0xb78b50,
original=1, inserted=0x7fff68b7a294) at grub-core/fs/zfs/zfs.c:917
#4  0x0000000000440d95 in zfs_mount (dev=0xb99c70) at
grub-core/fs/zfs/zfs.c:3299
#5  0x0000000000441ee1 in grub_zfs_dir (device=0xb99c70, path=0x474e14
"/") at grub-core/fs/zfs/zfs.c:3790
#6  0x0000000000454cc3 in grub_fs_probe (device=0xb99c70) at
grub-core/kern/fs.c:55
#7  0x0000000000454998 in grub_file_open (name=0xb99c50 "//") at
grub-core/kern/file.c:96
#8  0x00000000004033e6 in call_fill (filename=0x7fff68b7a8e0 "",
info=0x7fff68b7a920) at util/grub-mount.c:292
#9  0x00000000004344dc in grub_ufs_dir (device=0xb77740, path=0xb776e0
"/", hook=0x7fff68b7aac8) at grub-core/fs/ufs.c:640
#10 0x000000000040358d in fuse_readdir (buf=0xb77660,
fill=0x7ff9bd932a05<fill_dir>, off=0, fi=0x7fff68b7ac40) at
util/grub-mount.c:314
#11 0x00007ff9bd92eaba in fuse_fs_readdir (fs=0xb98f20, path=0xb99450
"/", buf=0xb77660, filler=0x7ff9bd932a05<fill_dir>, off=0,
fi=0x7fff68b7ac40) at fuse.c:1401
#12 0x00007ff9bd932dc3 in readdir_fill (f=0xb98e20, req=0xb775d0, ino=1,
size=4096, off=0, dh=0xb77660, fi=0x7fff68b7ac40) at fuse.c:2754
#13 0x00007ff9bd932ed7 in fuse_lib_readdir (req=0xb775d0, ino=1,
size=4096, off=0, llfi=0x7fff68b7acb0) at fuse.c:2780
#14 0x00007ff9bd938a25 in do_readdir (req=0xb775d0, nodeid=1,
inarg=0x7ff9bdf5b038) at fuse_lowlevel.c:846
#15 0x00007ff9bd93a3dd in fuse_ll_process (data=0xb99090,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_lowlevel.c:1514
#16 0x00007ff9bd93c3c1 in fuse_session_process (se=0xb77700,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_session.c:80
#17 0x00007ff9bd935ffa in fuse_session_loop (se=0xb77700) at fuse_loop.c:33
#18 0x00007ff9bd934c05 in fuse_loop (f=0xb98e20) at fuse.c:3436
#19 0x00007ff9bd93dff1 in fuse_main_common (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0, compat=0) at helper.c:330
#20 0x00007ff9bd93e059 in fuse_main_real (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0) at helper.c:342
#21 0x00000000004037c3 in fuse_init () at util/grub-mount.c:384
#22 0x0000000000403f2e in main (argc=3, argv=0x7fff68b7b058) at
util/grub-mount.c:558
(gdb)
#0  0x0000000000455555 in grub_memmove (dest=0xc8adb0, src=0xbf9dd0,
n=9575) at grub-core/kern/misc.c:61
#1  0x0000000000451ee3 in grub_memcpy (dest=0xc8adb0, src=0xbf9dd0,
n=32768) at ./include/grub/misc.h:62
#2  0x0000000000452eda in grub_disk_read (disk=0xb99c90,
sector=1953519424, offset=0, size=33792, buf=0xc8adb0) at
grub-core/kern/disk.c:550
#3  0x000000000043a21d in scan_disk (dev=0xb99c70, data=0xb78b50,
original=1, inserted=0x7fff68b7a294) at grub-core/fs/zfs/zfs.c:917
#4  0x0000000000440d95 in zfs_mount (dev=0xb99c70) at
grub-core/fs/zfs/zfs.c:3299
#5  0x0000000000441ee1 in grub_zfs_dir (device=0xb99c70, path=0x474e14
"/") at grub-core/fs/zfs/zfs.c:3790
#6  0x0000000000454cc3 in grub_fs_probe (device=0xb99c70) at
grub-core/kern/fs.c:55
#7  0x0000000000454998 in grub_file_open (name=0xb99c50 "//") at
grub-core/kern/file.c:96
#8  0x00000000004033e6 in call_fill (filename=0x7fff68b7a8e0 "",
info=0x7fff68b7a920) at util/grub-mount.c:292
#9  0x00000000004344dc in grub_ufs_dir (device=0xb77740, path=0xb776e0
"/", hook=0x7fff68b7aac8) at grub-core/fs/ufs.c:640
#10 0x000000000040358d in fuse_readdir (buf=0xb77660,
fill=0x7ff9bd932a05<fill_dir>, off=0, fi=0x7fff68b7ac40) at
util/grub-mount.c:314
#11 0x00007ff9bd92eaba in fuse_fs_readdir (fs=0xb98f20, path=0xb99450
"/", buf=0xb77660, filler=0x7ff9bd932a05<fill_dir>, off=0,
fi=0x7fff68b7ac40) at fuse.c:1401
#12 0x00007ff9bd932dc3 in readdir_fill (f=0xb98e20, req=0xb775d0, ino=1,
size=4096, off=0, dh=0xb77660, fi=0x7fff68b7ac40) at fuse.c:2754
#13 0x00007ff9bd932ed7 in fuse_lib_readdir (req=0xb775d0, ino=1,
size=4096, off=0, llfi=0x7fff68b7acb0) at fuse.c:2780
#14 0x00007ff9bd938a25 in do_readdir (req=0xb775d0, nodeid=1,
inarg=0x7ff9bdf5b038) at fuse_lowlevel.c:846
#15 0x00007ff9bd93a3dd in fuse_ll_process (data=0xb99090,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_lowlevel.c:1514
#16 0x00007ff9bd93c3c1 in fuse_session_process (se=0xb77700,
buf=0x7ff9bdf5b010 "P", len=80, ch=0xb98dd0) at fuse_session.c:80
#17 0x00007ff9bd935ffa in fuse_session_loop (se=0xb77700) at fuse_loop.c:33
#18 0x00007ff9bd934c05 in fuse_loop (f=0xb98e20) at fuse.c:3436
#19 0x00007ff9bd93dff1 in fuse_main_common (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0, compat=0) at helper.c:330
#20 0x00007ff9bd93e059 in fuse_main_real (argc=3, argv=0xb750c0,
op=0x68c3e0, op_size=328, user_data=0x0) at helper.c:342
#21 0x00000000004037c3 in fuse_init () at util/grub-mount.c:384
#22 0x0000000000403f2e in main (argc=3, argv=0x7fff68b7b058) at
util/grub-mount.c:558
(gdb)

what i found really odd are these:

#5  0x0000000000441ee1 in grub_zfs_dir (device=0xb99c70, path=0x474e14
"/") at grub-core/fs/zfs/zfs.c:3790
...
#9  0x00000000004344dc in grub_ufs_dir (device=0xb77740, path=0xb776e0
"/", hook=0x7fff68b7aac8) at grub-core/fs/ufs.c:640

first it thinks it's a ufs partition, and then tries zfs: WTF?!?!?
btw, i've been a freebsd user so this disk might have been formatted as
ufs in the past but it's lvm+ext3 only now.

--
bye,
p.