diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2017-11-30 06:08:05 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-22 15:43:56 +0100 |
| commit | 08e4d04569874f79963a40890e790d2b4c33ed30 (patch) | |
| tree | 434a294e4cbdb2db875dd2e29e8a6aaf2a6e51c8 | |
| parent | 30c68fb6582728657000627af186a99280c50721 (diff) | |
media: r820t: fix r820t_write_reg for KASAN
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>
| -rw-r--r-- | drivers/media/tuners/r820t.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/media/tuners/r820t.c b/drivers/media/tuners/r820t.c index 08dca40356d2..006dac6e8940 100644 --- a/drivers/media/tuners/r820t.c +++ b/drivers/media/tuners/r820t.c @@ -396,9 +396,11 @@ static int r820t_write(struct r820t_priv *priv, u8 reg, const u8 *val, 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) @@ -411,17 +413,18 @@ static int r820t_read_cache_reg(struct r820t_priv *priv, int reg) 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) |