From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Date: Sat, 28 Dec 2013 17:06:28 +0100 Subject: [U-Boot] [PATCH 1/3] mtd: onenand: Fix unaligned access In-Reply-To: <201312280007.42883.marex@denx.de> References: <1388016086-20293-1-git-send-email-marex@denx.de> <201312280007.42883.marex@denx.de> Message-ID: <20131228170628.5040ef54@jawa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Marek, > On Thursday, December 26, 2013 at 01:01:24 AM, Marek Vasut wrote: > > Fix unaligned access in OneNAND core. The problem is that the > > ffchars[] array is an array of "unsigned char", but in > > onenand_write_ops_nolock() can be passed to the memcpy_16() > > function. The memcpy_16() function will treat the buffer as an > > array of "unsigned short", thus triggering unaligned access if the > > compiler decided ffchars[] to be not aligned. > > > > I managed to trigger the problem with regular ELDK 5.4 GCC compiler. > > > > Signed-off-by: Marek Vasut > > Cc: Albert Aribaud > > Cc: Scott Wood > > Cc: Tom Rini > > --- > > drivers/mtd/onenand/onenand_base.c | 8 +++++++- > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/mtd/onenand/onenand_base.c > > b/drivers/mtd/onenand/onenand_base.c index 979e4af..e33e8d3 100644 > > --- a/drivers/mtd/onenand/onenand_base.c > > +++ b/drivers/mtd/onenand/onenand_base.c > > @@ -91,7 +91,13 @@ static struct nand_ecclayout onenand_oob_32 = { > > .oobfree = { {2, 3}, {14, 2}, {18, 3}, {30, 2} } > > }; > > > > -static const unsigned char ffchars[] = { > > +/* > > + * Warning! This array is used with the memcpy_16() function, thus > > + * it must be aligned to 2 bytes. GCC can make this array unaligned > > + * as the array is made of unsigned char, which memcpy16() doesn't > > + * like and will cause unaligned access. > > + */ > > +static const unsigned char __aligned(2) ffchars[] = { > > 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > > 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* > > 16 */ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > > Lukasz, can you please review this one? No problem, I will review the patch when I come back to the office (and be able to test it on the proper HW). > > Best regards, > Marek Vasut Best regards, Lukasz -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: not available URL: