Hi Jörn, I'm running some flash filesystem benchmarks for CELF, and I'm facing kernel segfaults when I try to umount my logfs filesystem. This happens with both 2.6.35 and 2.6.36-rc7. See the below trace. Has anyone else faced the same kind of issue? Don't hesitate to get back to me if you need more details or if there are commands you would like me to run. Thank you in advance for your help, Cheers, Michael. root@calao:~# cat /proc/cmdline console=ttyS0,115200n8 root=/dev/nfs ip=192.168.2.100 nfsroot=192.168.2.1:/home/mike/work/celf/RFS mtdparts=atmel_nand:128m(Main) root@calao:~# flash_eraseall /dev/mtd0 Erasing 128 Kibyte @ 8000000 -- 100 % complete. root@calao:~# mkfs.logfs /dev/mtdblock0 Will create filesystem with the following details: hex: decimal: fssize= 8000000 134217728 segsize= 40000 262144 blocksize= 1000 4096 writesize= 1 1 Do you wish to continue (yes/no) yes Finished generating LogFS root@calao:~# mount -t logfs /dev/mtdblock0 /mnt/flash/ root@calao:~# cp -rf /fs/8m/* /mnt/flash/ eth0: TX underrun, resetting buffers eth0: TX underrun, resetting buffers root@calao:~# umount /mnt/flash/ kernel BUG at fs/logfs/segment.c:858! Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c14a4000 [00000000] *pgd=23a3c031, *pte=00000000, *ppte=00000000 Internal error: Oops: 817 [#1] last sysfs file: /sys/devices/virtual/vc/vcs6/uevent Modules linked in: logfs zlib_deflate zlib_inflate CPU: 0 Not tainted (2.6.36-rc7 #1) PC is at __bug+0x18/0x24 LR is at __bug+0x14/0x24 pc : [<c0025764>] lr : [<c0025760>] psr: 20000013 sp : c2d91e18 ip : 00000000 fp : c2d91e84 r10: c03c3b80 r9 : 00000009 r8 : 00000000 r7 : c2d91e60 r6 : c3601d58 r5 : c3601d58 r4 : c03c3b80 r3 : 00000000 r2 : c033e368 r1 : 60000013 r0 : 0000002c Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 0005317f Table: 214a4000 DAC: 00000015 Process umount (pid: 1292, stack limit = 0xc2d90270) Stack: (0xc2d91e18 to 0xc2d92000) 1e00: bf022620 bf022630 1e20: bf022620 c0078360 ffffffff c0078a04 ffffffff c3601d58 c2d91e60 00000000 1e40: 0000000e 00000081 ffffffff c3601d58 c2d91e60 c0078b2c 00000000 00000000 1e60: 0000000e 00000000 c03e01a0 c03e01c0 c03e01e0 c03df100 c03df120 c03df140 1e80: c03df160 c03df180 c03df1a0 c03c3b80 c03986c0 c0398e40 c03c3ba0 c03c3bc0 1ea0: ffffffff ffffffff ffffffff 00000000 c2c1f800 c2d90000 c380dc60 c380dc78 1ec0: 00000000 c0078d70 ffffffff ffffffff c3601760 c3601cb8 c2c1f800 bf022104 1ee0: c3691830 c3601760 c035e708 c3601cb8 c035e708 c2c1f800 c035e848 c2d90000 1f00: c380dc60 c380dc78 00000000 c00a90f4 c3601cb8 c00a99b8 c2c1f800 c2d90000 1f20: bf0272e4 c035e848 c2d90000 c0098d04 c2c1f800 c3a7b000 c380dc60 bf0248e4 1f40: c2c1f800 bf028228 c380dc60 c0097f70 00000000 c2d91f68 c380dc60 c00ad3ac 1f60: 4003a000 c380dc78 c2d91f68 c2d91f68 c2d91f70 c2d91f70 c380dc60 c35fbab8 1f80: c2d90000 0001c530 0001aa1c 0001c518 00000034 c0021fe8 c2d90000 00000000 1fa0: 0001bab4 c0021e40 0001c530 0001aa1c 0001c530 00000000 00000048 00000000 1fc0: 0001c530 0001aa1c 0001c518 00000034 00000000 00000000 00000000 0001bab4 1fe0: 0001c560 be983c08 402c1c5c 402c1c7c 60000010 0001c530 e7d82003 e7c12007 [<c0025764>] (__bug+0x18/0x24) from [<bf022630>] (map_invalidatepage+0x10/0x18 [logfs]) [<bf022630>] (map_invalidatepage+0x10/0x18 [logfs]) from [<c0078360>] (do_invalidatepage+0x20/0x28) [<c0078360>] (do_invalidatepage+0x20/0x28) from [<c0078a04>] (truncate_inode_page+0xd4/0xe4) [<c0078a04>] (truncate_inode_page+0xd4/0xe4) from [<c0078b2c>] (truncate_inode_pages_range+0x118/0x344) [<c0078b2c>] (truncate_inode_pages_range+0x118/0x344) from [<c0078d70>] (truncate_inode_pages+0x18/0x20) [<c0078d70>] (truncate_inode_pages+0x18/0x20) from [<bf022104>] (logfs_evict_inode+0x40/0x188 [logfs]) [<bf022104>] (logfs_evict_inode+0x40/0x188 [logfs]) from [<c00a90f4>] (evict+0x20/0xb0) [<c00a90f4>] (evict+0x20/0xb0) from [<c00a99b8>] (iput+0x178/0x254) [<c00a99b8>] (iput+0x178/0x254) from [<c0098d04>] (generic_shutdown_super+0x78/0xe4) [<c0098d04>] (generic_shutdown_super+0x78/0xe4) from [<bf0248e4>] (logfs_kill_sb+0x40/0xf8 [logfs]) [<bf0248e4>] (logfs_kill_sb+0x40/0xf8 [logfs]) from [<c0097f70>] (deactivate_locked_super+0x44/0x58) [<c0097f70>] (deactivate_locked_super+0x44/0x58) from [<c00ad3ac>] (sys_umount+0x6c/0x33c) [<c00ad3ac>] (sys_umount+0x6c/0x33c) from [<c0021e40>] (ret_fast_syscall+0x0/0x2c) Code: e1a01000 e59f000c eb096367 e3a03000 (e5833000) ---[ end trace f09ed3af1a44d711 ]--- ------------[ cut here ]------------ WARNING: at kernel/exit.c:899 do_exit+0x5d4/0x624() Modules linked in: logfs zlib_deflate zlib_inflate [<c0027ae8>] (unwind_backtrace+0x0/0xf4) from [<c003a310>] (warn_slowpath_common+0x4c/0x64) [<c003a310>] (warn_slowpath_common+0x4c/0x64) from [<c003a344>] (warn_slowpath_null+0x1c/0x24) [<c003a344>] (warn_slowpath_null+0x1c/0x24) from [<c003e0a4>] (do_exit+0x5d4/0x624) [<c003e0a4>] (do_exit+0x5d4/0x624) from [<c0025c90>] (die+0x188/0x1c0) [<c0025c90>] (die+0x188/0x1c0) from [<c0029044>] (__do_kernel_fault+0x64/0x84) [<c0029044>] (__do_kernel_fault+0x64/0x84) from [<c0029198>] (do_page_fault+0x134/0x1d8) [<c0029198>] (do_page_fault+0x134/0x1d8) from [<c00212e4>] (do_DataAbort+0x34/0x98) [<c00212e4>] (do_DataAbort+0x34/0x98) from [<c0021a6c>] (__dabt_svc+0x4c/0x60) Exception stack(0xc2d91dd0 to 0xc2d91e18) 1dc0: 0000002c 60000013 c033e368 00000000 1de0: c03c3b80 c3601d58 c3601d58 c2d91e60 00000000 00000009 c03c3b80 c2d91e84 1e00: 00000000 c2d91e18 c0025760 c0025764 20000013 ffffffff [<c0021a6c>] (__dabt_svc+0x4c/0x60) from [<c0025764>] (__bug+0x18/0x24) [<c0025764>] (__bug+0x18/0x24) from [<bf022630>] (map_invalidatepage+0x10/0x18 [logfs]) [<bf022630>] (map_invalidatepage+0x10/0x18 [logfs]) from [<c0078360>] (do_invalidatepage+0x20/0x28) [<c0078360>] (do_invalidatepage+0x20/0x28) from [<c0078a04>] (truncate_inode_page+0xd4/0xe4) [<c0078a04>] (truncate_inode_page+0xd4/0xe4) from [<c0078b2c>] (truncate_inode_pages_range+0x118/0x344) [<c0078b2c>] (truncate_inode_pages_range+0x118/0x344) from [<c0078d70>] (truncate_inode_pages+0x18/0x20) [<c0078d70>] (truncate_inode_pages+0x18/0x20) from [<bf022104>] (logfs_evict_inode+0x40/0x188 [logfs]) [<bf022104>] (logfs_evict_inode+0x40/0x188 [logfs]) from [<c00a90f4>] (evict+0x20/0xb0) [<c00a90f4>] (evict+0x20/0xb0) from [<c00a99b8>] (iput+0x178/0x254) [<c00a99b8>] (iput+0x178/0x254) from [<c0098d04>] (generic_shutdown_super+0x78/0xe4) [<c0098d04>] (generic_shutdown_super+0x78/0xe4) from [<bf0248e4>] (logfs_kill_sb+0x40/0xf8 [logfs]) [<bf0248e4>] (logfs_kill_sb+0x40/0xf8 [logfs]) from [<c0097f70>] (deactivate_locked_super+0x44/0x58) [<c0097f70>] (deactivate_locked_super+0x44/0x58) from [<c00ad3ac>] (sys_umount+0x6c/0x33c) [<c00ad3ac>] (sys_umount+0x6c/0x33c) from [<c0021e40>] (ret_fast_syscall+0x0/0x2c) ---[ end trace f09ed3af1a44d712 ]--- Segmentation fault -- Michael Opdenacker, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com + 33 621 604 642 -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to 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