0001-cfi_flash-do-not-reset-flash-when-probe-fails.patch

   1 From 14c7476b1cc961931e587aecae832f0c6e3edba1 Mon Sep 17 00:00:00 2001
   2 From: Mike Frysinger <vapier@gentoo.org>
   3 Date: Thu, 2 Oct 2008 01:47:55 -0400
   4 Subject: [PATCH] cfi_flash: do not reset flash when probe fails
   5
   6 The CFI flash driver starts at flash_init() which calls down into
   7 flash_get_size().  This starts by calling flash_detect_cfi().  If said
   8 function fails, flash_get_size() finishes by attempting to reset the
   9 flash.  Unfortunately, it does this with an info->portwidth set to 0x10
  10 which filters down into flash_make_cmd() and that happily smashes the
  11 stack by sticking info->portwidth bytes into a cfiword_t variable that
  12 lives on the stack.  On a 64bit system you probably won't notice, but
  13 killing the last 8 bytes on a 32bit system usually leads to a corrupt
  14 return address.  Which is what happens on a Blackfin system.
  15
  16 Signed-off-by: Mike Frysinger <vapier@gentoo.org>
  17 ---
  18  drivers/mtd/cfi_flash.c |    3 ++-
  19  1 files changed, 2 insertions(+), 1 deletions(-)
  20
  21 diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
  22 index 0d1ee8a..72d063a 100644
  23 --- a/drivers/mtd/cfi_flash.c
  24 +++ b/drivers/mtd/cfi_flash.c
  25 @@ -1932,9 +1932,10 @@ ulong flash_get_size (ulong base, int banknum)
  26                         /* XXX - Need to test on x8/x16 in parallel. */
  27                         info->portwidth >>= 1;
  28                 }
  29 +
  30 +               flash_write_cmd (info, 0, 0, info->cmd_reset);
  31         }
  32
  33 -       flash_write_cmd (info, 0, 0, info->cmd_reset);
  34         return (info->size);
  35  }
  36
  37 --
  38 1.6.0.2
  39