more random patches. who knows.

[patches.git] / 0001-cfi_flash-do-not-reset-flash-when-probe-fails.patch

From 14c7476b1cc961931e587aecae832f0c6e3edba1 Mon Sep 17 00:00:00 2001
From: Mike Frysinger <vapier@gentoo.org>
Date: Thu, 2 Oct 2008 01:47:55 -0400
Subject: [PATCH] cfi_flash: do not reset flash when probe fails

The CFI flash driver starts at flash_init() which calls down into
flash_get_size().  This starts by calling flash_detect_cfi().  If said
function fails, flash_get_size() finishes by attempting to reset the
flash.  Unfortunately, it does this with an info->portwidth set to 0x10
which filters down into flash_make_cmd() and that happily smashes the
stack by sticking info->portwidth bytes into a cfiword_t variable that
lives on the stack.  On a 64bit system you probably won't notice, but
killing the last 8 bytes on a 32bit system usually leads to a corrupt
return address.  Which is what happens on a Blackfin system.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
 drivers/mtd/cfi_flash.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index 0d1ee8a..72d063a 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -1932,9 +1932,10 @@ ulong flash_get_size (ulong base, int banknum)
 			/* XXX - Need to test on x8/x16 in parallel. */
 			info->portwidth >>= 1;
 		}
+
+		flash_write_cmd (info, 0, 0, info->cmd_reset);
 	}
 
-	flash_write_cmd (info, 0, 0, info->cmd_reset);
 	return (info->size);
 }
 
-- 
1.6.0.2