Hi,
The summary is allocated using the vmalloc
c->summary->sum_buf = vmalloc(c->sector_size);
The same buffer is using and passed to the under layer in the

jffs2_sum_write_data:
  vecs[0].iov_base = &isum;

        vecs[0].iov_len = sizeof(isum);

        vecs[1].iov_base = c->summary->sum_buf;

        vecs[1].iov_len = datasize;
        sum_ofs = jeb->offset + c->sector_size - jeb->free_size;
        dbg_summary("JFFS2: writing out data to flash to pos : 0x%08x\n",

                    sum_ofs);
        ret = jffs2_flash_writev(c, vecs, 2, sum_ofs, &retlen, 0);
So maybe it can't be directly mapped using a dma_map_sync.
Unable to handle kernel NULL pointer dereference at virtual address 00000000

pgd = c0004000

[00000000] *pgd=00000000

Internal error: Oops: 817 [#1]

Modules linked in:

CPU: 0    Not tainted  (2.6.23.14 #26)

PC is at consistent_sync+0x60/0xe4

LR is at 0xc0221be4

pc : [<c0027540>]    lr : [<c0221be4>]    psr: 60000013

sp : c1b29bb8  ip : c0221be4  fp : c1b29bd0

r10: 00000000  r9 : c024c5f8  r8 : 00000001

r7 : c024c610  r6 : 00000001  r5 : c286f4d0  r4 : c286f0b0

r3 : 00000000  r2 : 00000001  r1 : 00000001  r0 : 00000028

Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel

Control: c000717f  Table: 21cf0000  DAC: 00000017

Process pdflush (pid: 64, stack limit = 0xc1b28258)

Stack: (0xc1b29bb8 to 0xc1b2a000)

9ba0:                                                       2286f0b0

c2860000

9bc0: c02f9500 c1b29bfc c1b29bd4 c01078c4 c00274f0 0000efc0 c1cff440

00000420

9be0: 00000000 00002100 00000000 c141a680 c1b29c0c c1b29c00 c0129e38

c01077d0

9c00: c1b29c5c c1b29c10 c012a38c c0129df4 00000004 c286f0b0 00000420

c0329800

9c20: 00000420 00001df8 c286f0b0 00000000 c0329800 00000000 00557700

00000000

9c40: 00557700 00000000 00000000 00002100 c1b29c80 c1b29c60 c0124e9c

c012a1e4

9c60: c1b29cb4 c286f0b0 00002100 000041b0 c1a81e00 c1b29ce0 c1b29c84

c00cfde8

9c80: c0124e04 c1b29cb4 c286f0b0 0...
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