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 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
media-r820t-fix-r820t_write_reg-for-kasan.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 16c3ada89cff9a8c2a0eea34ffa1aa20af3f6008 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@xxxxxxxx>
Date: Thu, 30 Nov 2017 06:08:05 -0500
Subject: media: r820t: fix r820t_write_reg for KASAN
From: Arnd Bergmann <arnd@xxxxxxxx>
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@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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@xxxxxxxx are
queue-4.4/arm-spear600-add-missing-interrupt-parent-of-rtc.patch
queue-4.4/media-r820t-fix-r820t_write_reg-for-kasan.patch
queue-4.4/arm-dts-sti-add-gpio-polarity-for-hdmi-hpd-gpio-property.patch
queue-4.4/arm-spear13xx-fix-spics-gpio-controller-s-warning.patch
queue-4.4/x86-fix-build-warnign-with-32-bit-pae.patch
queue-4.4/mm-hide-a-warning-for-compile_test.patch
queue-4.4/arm-pxa-tosa-bt-add-module_license-tag.patch
queue-4.4/arm-dts-s5pv210-add-interrupt-parent-for-ohci.patch
queue-4.4/arm-spear13xx-fix-dmas-cells.patch