Subject: JFFS2 issue with v3.5.x and later on Atmel chips at least (was: Kernel oops since v3.5.x on Atmel chips)

From: [email-masked] (ludovic.desroches)
Date: Wed, 22 Aug 2012 15:00:16 -0000

Le 08/22/2012 12:28 PM, ludovic.desroches a ?crit :
> Hi,
>
> Doing some tests with the help of Lava (a Linaro tool), I get some
> kernel oops with 3.5.x on several chips at91sam9260, at91sam9261 and
> at91sam9m10g45.
>
> Most of the time the oops comes from the cascade BUG() call in
> kernel/timer.c but sometimes it comes from a bad PC value.
>
> With Lava, I got the crash each time. It happens after mounting a mtd
> partition, copying a file from it, removing this file from the flash
> memory and then unmounting the mtd partition.
>
> I couldn't reproduce manually this issue so maybe there is something
> related to time...
>
> Here I paste the usual oops and the one with the bad PC value:
>
> Starting kernel ...
>
> Uncompressing Linux... done, booting the kernel.
> Booting Linux on physical CPU 0
> Linux version 3.5.0 (ldesroches at ibiza) (gcc version 4.6.1 (Ubuntu/Linaro
> 4.6.1-9ubuntu3) ) #10 Wed Aug 22 09:17:23 CEST 2012
> CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
> CPU: VIVT data cache, VIVT instruction cache
> Machine: Atmel AT91SAM9260-EK
> Memory policy: ECC disabled, Data cache writeback
> AT91: Detected soc type: at91sam9260
> AT91: Detected soc subtype: Unknown
> AT91: sram at 0x2ff000 of 0x2000 mapped at 0xfef76000
> Clocks: CPU 198 MHz, master 99 MHz, main 18.432 MHz
> Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 16256
> Kernel command line: mem=64M console=ttyS0,115200
> mtdparts=atmel_nand:4M(bootstrap/uboot/kernel)ro,70M(rootfs),-(data)
> root=/dev/mtdblock1 rw rootfstype=jffs2 ip=192.168.1.16:::255.255.255.0:::
> PID hash table entries: 256 (order: -2, 1024 bytes)
> Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
> Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
> Memory: 64MB = 64MB total
> Memory: 60848k/60848k available, 4688k reserved, 0K highmem
> Virtual kernel memory layout:
>      vector  : 0xffff0000 - 0xffff1000   (   4 kB)
>      fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
>      vmalloc : 0xc4800000 - 0xff000000   ( 936 MB)
>      lowmem  : 0xc0000000 - 0xc4000000   (  64 MB)
>      modules : 0xbf000000 - 0xc0000000   (  16 MB)
>        .text : 0xc0008000 - 0xc039fee8   (3680 kB)
>        .init : 0xc03a0000 - 0xc03bd7c4   ( 118 kB)
>        .data : 0xc03be000 - 0xc03e8f00   ( 172 kB)
>         .bss : 0xc03e8f24 - 0xc03fb138   (  73 kB)
> NR_IRQS:192
> AT91: 96 gpio irqs in 3 banks
> sched_clock: 32 bits at 100 Hz, resolution 10000000ns, wraps every
> 4294967286ms
> Console: colour dummy device 80x30
> Calibrating delay loop... 98.71 BogoMIPS (lpj=493568)
> pid_max: default: 32768 minimum: 301
> Mount-cache hash table entries: 512
> CPU: Testing write buffer coherency: ok
> Setting up static identity map for 0x202af150 - 0x202af1a8
> devtmpfs: initialized
> NET: Registered protocol family 16
> AT91: Power Management (with slow clock mode)
> AT91: Starting after software reset
> bio: create slab <bio-0> at 0
> SCSI subsystem initialized
> usbcore: registered new interface driver usbfs
> usbcore: registered new interface driver hub
> usbcore: registered new device driver usb
> Advanced Linux Sound Architecture Driver Version 1.0.25.
> Switching to clocksource pit
> cfg80211: Calling CRDA to update world regulatory domain
> NET: Registered protocol family 2
> IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
> TCP established hash table entries: 2048 (order: 2, 16384 bytes)
> TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
> TCP: Hash tables configured (established 2048 bind 2048)
> TCP: reno registered
> UDP hash table entries: 256 (order: 0, 4096 bytes)
> UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
> NET: Registered protocol family 1
> RPC: Registered named UNIX socket transport module.
> RPC: Registered udp transport module.
> RPC: Registered tcp transport module.
> RPC: Registered tcp NFSv4.1 backchannel transport module.
> jffs2: version 2.2. (NAND) (SUMMARY)  ? 2001-2006 Red Hat, Inc.
> msgmni has been set to 118
> io scheduler noop registered (default)
> atmel_usart.0: ttyS0 at MMIO 0xfffff200 (irq = 1) is a ATMEL_SERIAL
> console [ttyS0] enabled
> atmel_usart.1: ttyS1 at MMIO 0xfffb0000 (irq = 6) is a ATMEL_SERIAL
> atmel_usart.2: ttyS2 at MMIO 0xfffb4000 (irq = 7) is a ATMEL_SERIAL
> brd: module loaded
> loop: module loaded
> atmel_nand: Use On Flash BBT
> atmel_nand atmel_nand: No DMA support for NAND access.
> NAND device: Manufacturer ID: 0xec, Chip ID: 0xda (Samsung NAND 256MiB
> 3,3V 8-bit), page size: 2048, OOB size: 64
> Bad block table found at page 131008, version 0x01
> Bad block table found at page 130944, version 0x01
> nand_read_bbt: bad block at 0x000009840000
> nand_read_bbt: bad block at 0x00000fb80000
> 3 cmdlinepart partitions found on MTD device atmel_nand
> Creating 3 MTD partitions on "atmel_nand":
> 0x000000000000-0x000000400000 : "bootstrap/uboot/kernel"
> 0x000000400000-0x000004a00000 : "rootfs"
> 0x000004a00000-0x000010000000 : "data"
> MACB_mii_bus: probed
> macb macb: eth0: Cadence MACB at 0xfffc4000 irq 21 (3a:1f:34:08:54:54)
> macb macb: eth0: attached PHY driver [Davicom DM9161A]
> (mii_bus:phy_addr=macb-ffffffff:00, irq=-1)
> ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> at91_ohci at91_ohci: can't request overcurrent gpio 0
> at91_ohci at91_ohci: AT91 OHCI
> at91_ohci at91_ohci: new USB bus registered, assigned bus number 1
> at91_ohci at91_ohci: irq 20, io mem 0x00500000
> usb usb1: New USB device found, idVendor=1d6b, idProduct=0001
> usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
> usb usb1: Product: AT91 OHCI
> usb usb1: Manufacturer: Linux 3.5.0 ohci_hcd
> usb usb1: SerialNumber: at91
> hub 1-0:1.0: USB hub found
> hub 1-0:1.0: 2 ports detected
> usbcore: registered new interface driver cdc_acm
> cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
> Initializing USB Mass Storage driver...
> usbcore: registered new interface driver usb-storage
> USB Mass Storage support registered.
> mousedev: PS/2 mouse device common for all mice
> TCP: cubic registered
> NET: Registered protocol family 17
> lib80211: common routines for IEEE802.11 drivers
> VFP support v0.3: not present
> input: gpio-keys as /devices/platform/gpio-keys/input/input0
> /home/ldesroches/workspace/linux/drivers/rtc/hctosys.c: unable to open
> rtc device (rtc0)
> IP-Config: Complete:
>       device=eth0, addr=192.168.1.16, mask=255.255.255.0,
> gw=255.255.255.255
>       host=192.168.1.16, domain=, nis-domain=(none)
>       bootserver=255.255.255.255, rootserver=255.255.255.255, rootpath=
> ALSA device list:
>    No soundcards found.
> macb macb: eth0: link up (100/Full)
> jffs2: Empty flash at 0x01fb1c68 ends at 0x01fb2000
> VFS: Mounted root (jffs2 filesystem) on device 31:1.
> devtmpfs: mounted
> Freeing init memory: 116K
> Starting logging: OK
> Populating  using udev: udevd[468]: starting version 182
> done
> Starting portmap: done
> Initializing random number generator... done.
> Starting network...
> ip: RTNETLINK answers: File exists
> Starting sshd: OK
>
> Welcome to Buildroot
> at91 login: root
> [root at at91 ~]#
> [root at at91 ~]#
> [root at at91 ~]# export PS1="$PS1 [rc=$(echo \$?)]: "
> [root at at91 ~]#  [rc=0]: mount -t jffs2 /dev/mtdblock2 /mnt/
> jffs2: Empty flash at 0x01fb1c68 ends at 0x01fb2000
> o_at91_lava/tmp [rc=0]: rm -rf /tmp/lava_results.tgz
> /tmp//srv/lava/instances/rf
> [root at at91 ~]#  [rc=0]: mkdir -p /tmp//srv/lava/instances/rfo_at91_lava/tmp
> tmp//srv/lava/instances/rfo_at91_lava/tmp/instances/rfo_at91_lava/tmp/*.bundle
> /
> eroot at at91 ~]#  [rc=0]: rm -f
> /mnt//srv/lava/instances/rfo_at91_lava/tmp/*.bundl
> [root at at91 ~]#  [rc=0]: umount /mnt/
> [root at at91 ~]#  [rc=0]: ------------[ cut here ]------------
> kernel BUG at /home/ldesroches/workspace/linux/kernel/timer.c:1091!
> Internal error: Oops - BUG: 0 [#1] ARM
> Modules linked in:
> CPU: 0    Not tainted  (3.5.0 #10)
> PC is at cascade+0x54/0x78
> LR is at cascade+0x60/0x78
> pc : [<c0023c80>]    lr : [<c0023c8c>]    psr: a0000093
> sp : c03bfec8  ip : ffffae00  fp : 00000000
> r10: c03ee540  r9 : 0000000a  r8 : 00000100
> r7 : c03bfec8  r6 : c03bfec8  r5 : 0000002e  r4 : c03ee6a0
> r3 : 00000000  r2 : 00000068  r1 : c3a60738  r0 : c03ee9ec
> Flags: NzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
> Control: 0005317f  Table: 23a58000  DAC: 00000017
> Process swapper (pid: 0, stack limit = 0xc03be270)
> Stack: (0xc03bfec8 to 0xc03c0000)
> fec0:                   c03faf70 c3a60738 0000002e c03ee6a0 c03be000
> 00000000
> fee0: c03ee560 c0023d98 c0145bc4 c3952ba0 00000000 00000000 c03cddf4
> 00000001
> ff00: 00000004 c03be000 c03ee560 00000100 c03ee540 c001f4b0 000027da
> c03cddf4
> ff20: 00000000 00000001 c03bff9c 00000001 00000000 fefff000 c03bff9c
> 20004000
> ff40: 41069265 203b834c 00000000 c001f890 fefff000 c000dfc8 c000e0cc
> c000e0e0
> ff60: a0000013 c000d398 00000000 0005317f 0005217f a0000013 c03be000
> c03c8f54
> ff80: c03e8fe8 c047c300 20004000 41069265 203b834c 00000000 a00000d3
> c03bffb0
> ffa0: c000e0cc c000e0e0 a0000013 ffffffff c000e0b4 c000e27c c03c60b0
> ffffffff
> ffc0: c03b9784 c03a070c ffffffff ffffffff c03a0274 00000000 00000000
> c03b9784
> ffe0: 00000000 00053175 c03c603c c03b9780 c03c8f4c 20008040 00000000
> 00000000
> [<c0023c80>] (cascade+0x54/0x78) from [<c0023d98>]
> (run_timer_softirq+0x68/0x1f4)
> [<c0023d98>] (run_timer_softirq+0x68/0x1f4) from [<c001f4b0>]
> (__do_softirq+0x7c/0x110)
> [<c001f4b0>] (__do_softirq+0x7c/0x110) from [<c001f890>]
> (irq_exit+0x40/0x4c)
> [<c001f890>] (irq_exit+0x40/0x4c) from [<c000dfc8>] (handle_IRQ+0x74/0x98)
> [<c000dfc8>] (handle_IRQ+0x74/0x98) from [<c000d398>] (__irq_svc+0x38/0x60)
> [<c000d398>] (__irq_svc+0x38/0x60) from [<c000e0e0>]
> (default_idle+0x2c/0x34)
> [<c000e0e0>] (default_idle+0x2c/0x34) from [<c000e27c>]
> (cpu_idle+0x78/0xd8)
> [<c000e27c>] (cpu_idle+0x78/0xd8) from [<c03a070c>]
> (start_kernel+0x280/0x2d0)
> Code: e591300c e3c33001 e1540003 0a000000 (e7f001f2)
> ---[ end trace 6105dc3872c7de5d ]---
> Kernel panic - not syncing: Fatal exception in interrupt
>
>
>
>
>
> Starting kernel ...
>
> Uncompressing Linux... done, booting the kernel.
> Booting Linux on physical CPU 0
> Linux version 3.5.0 (ldesroches at ibiza) (gcc version 4.6.1 (Ubuntu/Linaro
> 4.6.1-9ubuntu3) ) #10 Wed Aug 22 09:17:23 CEST 2012
> CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
> CPU: VIVT data cache, VIVT instruction cache
> Machine: Atmel AT91SAM9260-EK
> Memory policy: ECC disabled, Data cache writeback
> AT91: Detected soc type: at91sam9260
> AT91: Detected soc subtype: Unknown
> AT91: sram at 0x2ff000 of 0x2000 mapped at 0xfef76000
> Clocks: CPU 198 MHz, master 99 MHz, main 18.432 MHz
> Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 16256
> Kernel command line: mem=64M console=ttyS0,115200
> mtdparts=atmel_nand:4M(bootstrap/uboot/kernel)ro,70M(rootfs),-(data)
> root=/dev/mtdblock1 rw rootfstype=jffs2 ip=192.168.1.16:::255.255.255.0:::
> PID hash table entries: 256 (order: -2, 1024 bytes)
> Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
> Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
> Memory: 64MB = 64MB total
> Memory: 60848k/60848k available, 4688k reserved, 0K highmem
> Virtual kernel memory layout:
>      vector  : 0xffff0000 - 0xffff1000   (   4 kB)
>      fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
>      vmalloc : 0xc4800000 - 0xff000000   ( 936 MB)
>      lowmem  : 0xc0000000 - 0xc4000000   (  64 MB)
>      modules : 0xbf000000 - 0xc0000000   (  16 MB)
>        .text : 0xc0008000 - 0xc039fee8   (3680 kB)
>        .init : 0xc03a0000 - 0xc03bd7c4   ( 118 kB)
>        .data : 0xc03be000 - 0xc03e8f00   ( 172 kB)
>         .bss : 0xc03e8f24 - 0xc03fb138   (  73 kB)
> NR_IRQS:192
> AT91: 96 gpio irqs in 3 banks
> sched_clock: 32 bits at 100 Hz, resolution 10000000ns, wraps every
> 4294967286ms
> Console: colour dummy device 80x30
> Calibrating delay loop... 98.71 BogoMIPS (lpj=493568)
> pid_max: default: 32768 minimum: 301
> Mount-cache hash table entries: 512
> CPU: Testing write buffer coherency: ok
> Setting up static identity map for 0x202af150 - 0x202af1a8
> devtmpfs: initialized
> NET: Registered protocol family 16
> AT91: Power Management (with slow clock mode)
> AT91: Starting after software reset
> bio: create slab <bio-0> at 0
> SCSI subsystem initialized
> usbcore: registered new interface driver usbfs
> usbcore: registered new interface driver hub
> usbcore: registered new device driver usb
> Advanced Linux Sound Architecture Driver Version 1.0.25.
> Switching to clocksource pit
> cfg80211: Calling CRDA to update world regulatory domain
> NET: Registered protocol family 2
> IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
> TCP established hash table entries: 2048 (order: 2, 16384 bytes)
> TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
> TCP: Hash tables configured (established 2048 bind 2048)
> TCP: reno registered
> UDP hash table entries: 256 (order: 0, 4096 bytes)
> UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
> NET: Registered protocol family 1
> RPC: Registered named UNIX socket transport module.
> RPC: Registered udp transport module.
> RPC: Registered tcp transport module.
> RPC: Registered tcp NFSv4.1 backchannel transport module.
> jffs2: version 2.2. (NAND) (SUMMARY)  ? 2001-2006 Red Hat, Inc.
> msgmni has been set to 118
> io scheduler noop registered (default)
> atmel_usart.0: ttyS0 at MMIO 0xfffff200 (irq = 1) is a ATMEL_SERIAL
> console [ttyS0] enabled
> atmel_usart.1: ttyS1 at MMIO 0xfffb0000 (irq = 6) is a ATMEL_SERIAL
> atmel_usart.2: ttyS2 at MMIO 0xfffb4000 (irq = 7) is a ATMEL_SERIAL
> brd: module loaded
> loop: module loaded
> atmel_nand: Use On Flash BBT
> atmel_nand atmel_nand: No DMA support for NAND access.
> NAND device: Manufacturer ID: 0xec, Chip ID: 0xda (Samsung NAND 256MiB
> 3,3V 8-bit), page size: 2048, OOB size: 64
> Bad block table found at page 131008, version 0x01
> Bad block table found at page 130944, version 0x01
> nand_read_bbt: bad block at 0x000009840000
> nand_read_bbt: bad block at 0x00000fb80000
> 3 cmdlinepart partitions found on MTD device atmel_nand
> Creating 3 MTD partitions on "atmel_nand":
> 0x000000000000-0x000000400000 : "bootstrap/uboot/kernel"
> 0x000000400000-0x000004a00000 : "rootfs"
> 0x000004a00000-0x000010000000 : "data"
> MACB_mii_bus: probed
> macb macb: eth0: Cadence MACB at 0xfffc4000 irq 21 (3a:1f:34:08:54:54)
> macb macb: eth0: attached PHY driver [Davicom DM9161A]
> (mii_bus:phy_addr=macb-ffffffff:00, irq=-1)
> ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> at91_ohci at91_ohci: can't request overcurrent gpio 0
> at91_ohci at91_ohci: AT91 OHCI
> at91_ohci at91_ohci: new USB bus registered, assigned bus number 1
> at91_ohci at91_ohci: irq 20, io mem 0x00500000
> usb usb1: New USB device found, idVendor=1d6b, idProduct=0001
> usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
> usb usb1: Product: AT91 OHCI
> usb usb1: Manufacturer: Linux 3.5.0 ohci_hcd
> usb usb1: SerialNumber: at91
> hub 1-0:1.0: USB hub found
> hub 1-0:1.0: 2 ports detected
> usbcore: registered new interface driver cdc_acm
> cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
> Initializing USB Mass Storage driver...
> usbcore: registered new interface driver usb-storage
> USB Mass Storage support registered.
> mousedev: PS/2 mouse device common for all mice
> TCP: cubic registered
> NET: Registered protocol family 17
> lib80211: common routines for IEEE802.11 drivers
> VFP support v0.3: not present
> input: gpio-keys as /devices/platform/gpio-keys/input/input0
> /home/ldesroches/workspace/linux/drivers/rtc/hctosys.c: unable to open
> rtc device (rtc0)
> IP-Config: Complete:
>       device=eth0, addr=192.168.1.16, mask=255.255.255.0,
> gw=255.255.255.255
>       host=192.168.1.16, domain=, nis-domain=(none)
>       bootserver=255.255.255.255, rootserver=255.255.255.255, rootpath=
> ALSA device list:
>    No soundcards found.
> macb macb: eth0: link up (100/Full)
> jffs2: Empty flash at 0x01fb1c68 ends at 0x01fb2000
> VFS: Mounted root (jffs2 filesystem) on device 31:1.
> devtmpfs: mounted
> Freeing init memory: 116K
> Starting logging: OK
> Populating  using udev: done
> udevd[468]: starting version 182
> Starting portmap: done
> Initializing random number generator... done.
> Starting network...
> ip: RTNETLINK answers: File exists
> Starting sshd: OK
>
> Welcome to Buildroot
> at91 login: root
> [root at at91 ~]#
> [root at at91 ~]#
> [root at at91 ~]# export PS1="$PS1 [rc=$(echo \$?)]: "
> [root at at91 ~]#  [rc=0]: mount -t jffs2 /dev/mtdblock2 /mnt/
> jffs2: Empty flash at 0x01fb1c68 ends at 0x01fb2000
> o_at91_lava/tmp [rc=0]: rm -rf /tmp/lava_results.tgz
> /tmp//srv/lava/instances/rf
> [root at at91 ~]#  [rc=0]: mkdir -p /tmp//srv/lava/instances/rfo_at91_lava/tmp
> tmp//srv/lava/instances/rfo_at91_lava/tmp/instances/rfo_at91_lava/tmp/*.bundle
> /
> eroot at at91 ~]#  [rc=0]: rm -f
> /mnt//srv/lava/instances/rfo_at91_lava/tmp/*.bundl
> [root at at91 ~]#  [rc=0]: umount /mnt/
> [root at at91 ~]#  [rc=0]: Unable to handle kernel paging request at
> virtual address 0d0c951c
> pgd = c0004000
> [0d0c951c] *pgd=00000000
> Internal error: Oops: 80000005 [#1] ARM
> Modules linked in:
> CPU: 0    Not tainted  (3.5.0 #10)
> PC is at 0xd0c951c
> LR is at run_timer_softirq+0x144/0x1f4
> pc : [<0d0c951c>]    lr : [<c0023e74>]    psr: 20000013
> sp : c03bfee8  ip : 00200200  fp : 00000000
> r10: 0d0c951c  r9 : 0000000a  r8 : c03bfef0
> r7 : c03ee560  r6 : 00000100  r5 : c03be000  r4 : c03ee6a0
> r3 : 20000013  r2 : 00000000  r1 : c03bfef0  r0 : b5a01535
> Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
> Control: 0005317f  Table: 23a58000  DAC: 00000017
> Process swapper (pid: 0, stack limit = 0xc03be270)
> Stack: (0xc03bfee8 to 0xc03c0000)
> fee0:                   c0145bc4 c396dba0 c03bfef0 c03bfef0 c03cddf4
> 00000001
> ff00: 00000004 c03be000 c03ee560 00000100 c03ee540 c001f4b0 00002870
> c03cddf4
> ff20: 00000000 00000001 c03bff9c 00000001 00000000 fefff000 c03bff9c
> 20004000
> ff40: 41069265 203b834c 00000000 c001f890 fefff000 c000dfc8 c000e0cc
> c000e0e0
> ff60: a0000013 c000d398 00000000 0005317f 0005217f a0000013 c03be000
> c03c8f54
> ff80: c03e8fe8 c047c300 20004000 41069265 203b834c 00000000 a00000d3
> c03bffb0
> ffa0: c000e0cc c000e0e0 a0000013 ffffffff c000e0b4 c000e27c c03c60b0
> ffffffff
> ffc0: c03b9784 c03a070c ffffffff ffffffff c03a0274 00000000 00000000
> c03b9784
> ffe0: 00000000 00053175 c03c603c c03b9780 c03c8f4c 20008040 00000000
> 00000000
> [<c0023e74>] (run_timer_softirq+0x144/0x1f4) from [<c001f4b0>]
> (__do_softirq+0x7c/0x110)
> [<c001f4b0>] (__do_softirq+0x7c/0x110) from [<c001f890>]
> (irq_exit+0x40/0x4c)
> [<c001f890>] (irq_exit+0x40/0x4c) from [<c000dfc8>] (handle_IRQ+0x74/0x98)
> [<c000dfc8>] (handle_IRQ+0x74/0x98) from [<c000d398>] (__irq_svc+0x38/0x60)
> [<c000d398>] (__irq_svc+0x38/0x60) from [<c000e0e0>]
> (default_idle+0x2c/0x34)
> [<c000e0e0>] (default_idle+0x2c/0x34) from [<c000e27c>]
> (cpu_idle+0x78/0xd8)
> [<c000e27c>] (cpu_idle+0x78/0xd8) from [<c03a070c>]
> (start_kernel+0x280/0x2d0)
> Code: bad PC value
> ---[ end trace f65db9c681fbd6e3 ]---
> Kernel panic - not syncing: Fatal exception in interrupt
>
>
>
> Regards
>
> Ludovic
>
>

After bisection the commit causing this issue is:

commit 8bdc81c5069e43755d6e59e5e990e21ca200e8e2
Author: Artem Bityutskiy <[email-masked]>
Date:   Mon May 7 19:56:53 2012 +0300

     jffs2: get rid of jffs2_sync_super

     Currently JFFS2 file-system maps the VFS "superblock" abstraction 
to the
     write-buffer. Namely, it uses VFS services to synchronize the 
write-buffer
     periodically.

     The whole "superblock write-out" VFS infrastructure is served by the
     'sync_supers()' kernel thread, which wakes up every 5 (by default) 
seconds and
     writes out all dirty superblock using the '->write_super()' 
call-back. But the
     problem with this thread is that it wastes power by waking up the 
system every
     5 seconds no matter what. So we want to kill it completely and 
thus, we need to
     make file-systems to stop using the '->write_super' VFS service, 
and then
     remove it together with the kernel thread.

     This patch switches the JFFS2 write-buffer management from
     '->write_super()'/'->s_dirt' to a delayed work. Instead of setting 
the 's_dirt'
     flag we just schedule a delayed work for synchronizing the 
write-buffer.

     Signed-off-by: Artem Bityutskiy <[email-masked]>
     Signed-off-by: Al Viro <[email-masked]>

Once reverted my issue disappeared. Tests have been done on at91sam9m10g45.

Regards

Ludovic