Re: [PATCH] mtd: gpmi-nand: Fix kernel crash due to missing verify_buf

Marek Vasut
2012-08-10T22:58:07Z

Dear Fabio Estevam,

> From: Fabio Estevam <fabio.estevam@freescale.com>
>
> When selecting CONFIG_MTD_NAND_VERIFY_WRITE=y and doing simple write tests
> the following kernel crash happens:
>
> root@freescale /$ dd if=/dev/zero of=/dev/mtd0 bs=128k count=1
> [ 41.070000] Unable to handle kernel NULL pointer dereference at virtual
> addr0 [ 41.080000] pgd = c77ac000
> [ 41.080000] [00000000] *pgd=4773c831, *pte=00000000, *ppte=00000000
> [ 41.090000] Internal error: Oops: 17 [#1] ARM
> [ 41.090000] Modules linked in:
> [ 41.090000] CPU: 0 Not tainted
> (3.6.0-rc1-next-20120809-00002-ga25d017-d) [ 41.090000] PC is at
> nand_verify_buf+0x18/0x5c
> [ 41.090000] LR is at nand_write_page+0xc0/0x140
> [ 41.090000] pc : [<c023e7d4>] lr : [<c023fcfc>] psr: 20000013
> [ 41.090000] sp : c7779de4 ip : 00000000 fp : c6e60000
> [ 41.090000] r10: 00000000 r9 : 00020000 r8 : 00000000
> [ 41.090000] r7 : 00000000 r6 : c6e60000 r5 : c762cb10 r4 : 00000000
> [ 41.090000] r3 : c762c8a8 r2 : 00000800 r1 : c6e60000 r0 : 00000000
> [ 41.090000] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment
> user [ 41.090000] Control: 0005317f Table: 477ac000 DAC: 00000015
> [ 41.090000] Process dd (pid: 427, stack limit = 0xc7778270)
> [ 41.090000] Stack: (0xc7779de4 to 0xc777a000)
> ...
>
> The NULL pointer dereference that happens in nand_verify_buf() is due to
> the missing gpmi_verify_buf implementation in the gpmi-nand driver.
>
> Implement gpmi_verify_buf() to prevent this crash.
[...]

Acked-by: Marek Vasut <marex@denx.de>

Definitelly should go for stable too.

Best regards,
Marek Vasut