Re: [PATCH 2/2] [MTD] Call bdi_init() and bdi_register()

[Jens Axboe <jens.axboe@oracle.com>]

On Tue, Apr 27 2010, Paolo Minazzi wrote:
> I have tried this patch.
> I have enabled LOGFS, but not mounted partition with it.
> /dev/mtdblock1 is my romfs root partition and it is OK.
> 
> The problem is that init cannot mount my /dev/mtdblock1 romfs root.
> 
> This is the fault :
> Platform: Cirrus Logic EDB9315A Board (ARM920T) Rev A
> Copyright (C) 2000, 2001, 2002, Red Hat, Inc.
>        |----------------------------------------------
> Raw file loaded 0x00080000-0x001dce6b, assumed entry at
> 0x00080000-----------------------------------------------------------
> RedBoot> exec -s 0x00b00000 -r 0x00a00000 -c "root=/dev/mtdblock1
> console=ttyAM console=tty1"--------------------------------
> ENTRY=0xc0008000-------------------------------------------------------------------------------------------------------------
> LENGTH=0x00300000------------------------------------------------------------------------------------------------------------
> BASE_ADDR=0x00080000---------------------------------------------------------------------------------------------------------
> Using base address 0x00080000 and length
> 0x00300000--------------------------------------------------------------------------
> Uncompressing Linux... done, booting the kernel.
> Linux version 2.6.34-rc5 (root@darkstar) (gcc version 3.4.3) #18 Tue
> Apr 27 10:55:55 CEST 2010
> CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c0007177
> CPU: VIVT data cache, VIVT instruction cache
> Machine: Cirrus Logic EDB9315A Evaluation Board
> Memory policy: ECC disabled, Data cache writeback
> Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 32512
> Kernel command line: root=/dev/mtdblock1 console=ttyAM console=tty1
> PID hash table entries: 512 (order: -1, 2048 bytes)
> Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
> Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
> Memory: 128MB = 128MB total
> Memory: 126928k/126928k available, 4144k reserved, 0K highmem
> Virtual kernel memory layout:
>     vector  : 0xffff0000 - 0xffff1000   (   4 kB)
>     fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
>     DMA     : 0xffc00000 - 0xffe00000   (   2 MB)
>     vmalloc : 0xc8800000 - 0xfe800000   ( 864 MB)
>     lowmem  : 0xc0000000 - 0xc8000000   ( 128 MB)
>     modules : 0xbf000000 - 0xc0000000   (  16 MB)
>       .init : 0xc0008000 - 0xc0036000   ( 184 kB)
>       .text : 0xc0036000 - 0xc02ab000   (2516 kB)
>       .data : 0xc02ac000 - 0xc02c4e00   ( 100 kB)
> SLUB: Genslabs=11, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> Hierarchical RCU implementation.
> NR_IRQS:120
> VIC @fefb0000: id 0x00041190, vendor 0x41
> VIC @fefc0000: id 0x00041190, vendor 0x41
> Console: colour dummy device 80x30
> console [tty1] enabled
> Calibrating delay loop... 99.73 BogoMIPS (lpj=498688)
> Mount-cache hash table entries: 512
> CPU: Testing write buffer coherency: ok
> NET: Registered protocol family 16
> ep93xx clock: PLL1 running at 200 MHz, PLL2 at 48 MHz
> ep93xx clock: FCLK 200 MHz, HCLK 100 MHz, PCLK 50 MHz
> ep93xx dma_m2p: M2P DMA subsystem initialized
> 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
> NET: Registered protocol family 2
> IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
> TCP established hash table entries: 4096 (order: 3, 32768 bytes)
> TCP bind hash table entries: 4096 (order: 2, 16384 bytes)
> TCP: Hash tables configured (established 4096 bind 4096)
> 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
> JFFS2 version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
> ***REGISTER LOGFS
> ***REGISTER LOGFS DONE ret=0
> ROMFS MTD (C) 2007 Red Hat, Inc.
> msgmni has been set to 247
> io scheduler noop registered
> io scheduler deadline registered
> io scheduler cfq registered (default)
> Console: switching to colour frame buffer device 100x37
> graphics fb0: registered. Mode = 800x600-16
> Serial: AMBA driver
> apb:uart1: ttyAM0 at MMIO 0x808c0000 (irq = 52) is a AMBA
> console [ttyAM0] enabled
> apb:uart2: ttyAM1 at MMIO 0x808d0000 (irq = 54) is a AMBA
> apb:uart3: ttyAM2 at MMIO 0x808e0000 (irq = 55) is a AMBA
> dev->num_resources=1
> physmap platform flash device: 02000000 at 60000000
> physmap-flash.0: Found 1 x16 devices at 0x0 in 16-bit bank
> physmap-flash.0: Found 1 x16 devices at 0x1000000 in 16-bit bank
>  Intel/Sharp Extended Query Table at 0x0031
>  Intel/Sharp Extended Query Table at 0x0031
> Using buffer write method
> cfi_cmdset_0001: Erase suspend on write enabled
> cmdlinepart partition parsing not available
> Searching for RedBoot partition table in physmap-flash.0 at offset 0x1fe0000
> 6 RedBoot partitions found on MTD device physmap-flash.0
> Creating 6 MTD partitions on "physmap-flash.0":
> 0x000000000000-0x000000040000 : "RedBoot"
> 0x000000040000-0x000000b40000 : "ramdisk"
> 0x000000b40000-0x000000e40000 : "zImage"
> 0x000000e40000-0x000001fc0000 : "jffs2"
> 0x000001fc0000-0x000001fe0000 : "RedBoot config"
> 0x000001fe0000-0x000002000000 : "FIS directory"
> PPP generic driver version 2.4.2
> PPP Deflate Compression module registered
> PPP BSD Compression module registered
> ep93xx-eth version 0.1 loading
> eth0: ep93xx on-chip ethernet, IRQ 39, 00:00:11:22:33:36
> ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> ep93xx-ohci ep93xx-ohci: EP93xx OHCI
> ep93xx-ohci ep93xx-ohci: new USB bus registered, assigned bus number 1
> ep93xx-ohci ep93xx-ohci: irq 56, io mem 0x80020000
> hub 1-0:1.0: USB hub found
> hub 1-0:1.0: 3 ports detected
> usbcore: registered new interface driver cdc_acm
> cdc_acm: v0.26: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.
> ep93xx-rtc ep93xx-rtc: rtc core: registered ep93xx-rtc as rtc0
> usbcore: registered new interface driver usbhid
> usbhid: USB HID core driver
> TCP cubic registered
> NET: Registered protocol family 17
> Last power-down at UTC 08:47:16 on 27/04/2010
> ep93xx-rtc ep93xx-rtc: setting system clock to 2010-04-27 08:47:16 UTC
> (1272358036)
> VFS: Cannot open root device "mtdblock1" or unknown-block(31,1)
> Please append a correct "root=" boot option; here are the available partitions:
> 1f00             256 mtdblock0 (driver?)
> 1f01           11264 mtdblock1 (driver?)
> 1f02            3072 mtdblock2 (driver?)
> 1f03           17920 mtdblock3 (driver?)
> 1f04             128 mtdblock4 (driver?)
> 1f05             128 mtdblock5 (driver?)
> Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,1)
> Backtrace:
> [<c003a3dc>] (dump_backtrace+0x0/0x12c) from [<c003a520>] (dump_stack+0x18/0x1c)
>  r7:c7c11000 r6:fffffffb r5:c7c11000 r4:00000000
> [<c003a508>] (dump_stack+0x0/0x1c) from [<c0046628>] (panic+0x3c/0xc4)
> [<c00465ec>] (panic+0x0/0xc4) from [<c0008d58>] (mount_block_root+0x110/0x2e8)
>  r3:00000000 r2:20000013 r1:c7c27f58 r0:c0276b44
> [<c0008c48>] (mount_block_root+0x0/0x2e8) from [<c0008f84>]
> (mount_root+0x54/0x6c)
> [<c0008f30>] (mount_root+0x0/0x6c) from [<c0009094>]
> (prepare_namespace+0xf8/0x194)
>  r5:c001a56c r4:c001a570
> [<c0008f9c>] (prepare_namespace+0x0/0x194) from [<c0008aa4>]
> (kernel_init+0x114/0x15c)
>  r6:c0019b0c r5:c0019d5c r4:c02c4e18
> [<c0008990>] (kernel_init+0x0/0x15c) from [<c0048e98>] (do_exit+0x0/0x628)
>  r6:00000000 r5:00000000 r4:00000000
> 
> 
> 
> If I disable logfs, my root /dev/mtdblock1 is mounted correclty.

So this issue looks unrelated, but a bug none the less (if just enabling
logfs breaks the mount).

-- 
Jens Axboe