Re: Boot failure on Arndale with next-20131105

[Jens Axboe <axboe@kernel.dk>]

On 11/05/2013 04:49 AM, Tushar Behera wrote:
> Hi,
> 
> We are having a boot-time kernel panic on Samsung's Exynos5250-based
> Arndale board with next-20131105. Bisect points to following commit.
> 
> <<<
> commit febca1baea1cfe2d7a0271385d89b03d5fb34f94
> Author: Chris Mason <chris.mason@fusionio.com>
> Date:   Thu Oct 31 13:32:42 2013 -0600
> 
>     block: setup bi_vcnt on clones
> 
>     commit 9fc6286f347d changed the cloning code to make clones cheaper for
>     the case where we don't need to clone the iovec array.  But,
>     the new clone needs the bi_vnct from the original.
> 
>     Signed-off-by: Chris Mason <chris.mason@fusionio.com>
>     Signed-off-by: Jens Axboe <axboe@kernel.dk>
>>>>
> 
> Reverting above commit, Arndale is able to boot again.
> 
> Excerpts from the boot log (just in case, it helps in debugging).
> 
> [    1.972062] Unable to handle kernel paging request at virtual
> address 025e63a0
> [    1.981164] pgd = c0004000
> [    1.982375] [025e63a0] *pgd=00000000
> [    1.985875] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
> [    1.991086] Modules linked in:
> [    1.994076] CPU: 0 PID: 1178 Comm: mmcqd/0 Not tainted
> 3.12.0-rc5-00051-gfebca1b #21
> [    2.001683] task: ef3530c0 ti: ee82e000 task.ti: ee82e000
> [    2.006981] PC is at dma_cache_maint_page+0x84/0x174
> [    2.011842] LR is at 0x6
> 
> [    2.043532] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM
> Segment kernel
> [    2.050708] Control: 10c5387d  Table: 4000406a  DAC: 00000015
> [    2.056342] Process mmcqd/0 (pid: 1178, stack limit = 0xee82e240)
> [    2.062321] Stack: (0xee82fd58 to 0xee830000)
> 
> [ ... ]
> 
> [    2.275352] [<c0015768>] (dma_cache_maint_page+0x84/0x174) from
> [<c0015880>] (__dma_page_cpu_to_dev+0x28/0xa0)
> [    2.285170] [<c0015880>] (__dma_page_cpu_to_dev+0x28/0xa0) from
> [<c00159a4>] (arm_dma_map_page+0x6c/0x70)
> [    2.294565] [<c00159a4>] (arm_dma_map_page+0x6c/0x70) from
> [<c0015d28>] (arm_dma_map_sg+0x74/0xec)
> [    2.303366] [<c0015d28>] (arm_dma_map_sg+0x74/0xec) from
> [<c02bf534>] (dw_mci_pre_dma_transfer.isra.16+0x124/0x15c)
> [    2.313614] [<c02bf534>]
> (dw_mci_pre_dma_transfer.isra.16+0x124/0x15c) from [<c02bf8d4>]
> (dw_mci_pre_req+0x44/0x50)
> [    2.323863] [<c02bf8d4>] (dw_mci_pre_req+0x44/0x50) from
> [<c02a8970>] (mmc_start_req+0x3c/0x39c)
> [    2.332486] [<c02a8970>] (mmc_start_req+0x3c/0x39c) from
> [<c02b606c>] (mmc_blk_issue_rw_rq+0xbc/0xa9c)
> [    2.341625] [<c02b606c>] (mmc_blk_issue_rw_rq+0xbc/0xa9c) from
> [<c02b6c14>] (mmc_blk_issue_rq+0x1c8/0x498)
> [    2.351106] [<c02b6c14>] (mmc_blk_issue_rq+0x1c8/0x498) from
> [<c02b75d4>] (mmc_queue_thread+0xa4/0x144)
> [    2.360331] [<c02b75d4>] (mmc_queue_thread+0xa4/0x144) from
> [<c0038614>] (kthread+0xb4/0xb8)
> [    2.368616] [<c0038614>] (kthread+0xb4/0xb8) from [<c000e2f8>]
> (ret_from_fork+0x14/0x3c)
> [    2.376556] Code: 17e81051 10822181 e592c000 e3ccc003 (e79c2007)
> [    2.382570] ---[ end trace df06b64b1b7fa443 ]---
> 
> [ ... ]
> 
> Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done.
> Gave up waiting for root device.  Common problems:
>  - Boot args (cat /proc/cmdline)
>    - Check rootdelay= (did the system wait long enough?)
>    - Check root= (did the system wait for the right device?)
>  - Missing modules (cat /proc/modules; ls /dev)
> ALERT!  /dev/mmcblk1p3 does not exist.  Dropping to a shell!
> FATAL: Could not load
> /lib/modules/3.12.0-rc5-00051-gfebca1b/modules.dep: No such file or
> directory
> FATAL: Could not load
> /lib/modules/3.12.0-rc5-00051-gfebca1b/modules.dep: No such file or
> directory

Very weird! What file system is being used?

-- 
Jens Axboe