This is a note to let you know that I've just added the patch titled
media: r820t: fix r820t_write_reg for KASAN
to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: media-r820t-fix-r820t_write_reg-for-kasan.patch and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 16c3ada89cff9a8c2a0eea34ffa1aa20af3f6008 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann arnd@arndb.de Date: Thu, 30 Nov 2017 06:08:05 -0500 Subject: media: r820t: fix r820t_write_reg for KASAN
From: Arnd Bergmann arnd@arndb.de
commit 16c3ada89cff9a8c2a0eea34ffa1aa20af3f6008 upstream.
With CONFIG_KASAN, we get an overly long stack frame due to inlining the register access functions:
drivers/media/tuners/r820t.c: In function 'generic_set_freq.isra.7': drivers/media/tuners/r820t.c:1334:1: error: the frame size of 2880 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
This is caused by a gcc bug that has now been fixed in gcc-8. To work around the problem, we can pass the register data through a local variable that older gcc versions can optimize out as well.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Mauro Carvalho Chehab mchehab@s-opensource.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/media/tuners/r820t.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
--- a/drivers/media/tuners/r820t.c +++ b/drivers/media/tuners/r820t.c @@ -410,9 +410,11 @@ static int r820t_write(struct r820t_priv return 0; }
-static int r820t_write_reg(struct r820t_priv *priv, u8 reg, u8 val) +static inline int r820t_write_reg(struct r820t_priv *priv, u8 reg, u8 val) { - return r820t_write(priv, reg, &val, 1); + u8 tmp = val; /* work around GCC PR81715 with asan-stack=1 */ + + return r820t_write(priv, reg, &tmp, 1); }
static int r820t_read_cache_reg(struct r820t_priv *priv, int reg) @@ -425,17 +427,18 @@ static int r820t_read_cache_reg(struct r return -EINVAL; }
-static int r820t_write_reg_mask(struct r820t_priv *priv, u8 reg, u8 val, +static inline int r820t_write_reg_mask(struct r820t_priv *priv, u8 reg, u8 val, u8 bit_mask) { + u8 tmp = val; int rc = r820t_read_cache_reg(priv, reg);
if (rc < 0) return rc;
- val = (rc & ~bit_mask) | (val & bit_mask); + tmp = (rc & ~bit_mask) | (tmp & bit_mask);
- return r820t_write(priv, reg, &val, 1); + return r820t_write(priv, reg, &tmp, 1); }
static int r820t_read(struct r820t_priv *priv, u8 reg, u8 *val, int len)
Patches currently in stable-queue which might be from arnd@arndb.de are
queue-3.18/arm-spear600-add-missing-interrupt-parent-of-rtc.patch queue-3.18/media-r820t-fix-r820t_write_reg-for-kasan.patch queue-3.18/arm-spear13xx-fix-spics-gpio-controller-s-warning.patch queue-3.18/arm-dts-s5pv210-add-interrupt-parent-for-ohci.patch queue-3.18/arm-spear13xx-fix-dmas-cells.patch