media: saa7146: avoid high stack usage with clang
authorArnd Bergmann <arnd@arndb.de>
Tue, 19 Feb 2019 17:01:56 +0000 (12:01 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 31 May 2019 13:46:33 +0000 (06:46 -0700)
[ Upstream commit 03aa4f191a36f33fce015387f84efa0eee94408e ]

Two saa7146/hexium files contain a construct that causes a warning
when built with clang:

drivers/media/pci/saa7146/hexium_orion.c:210:12: error: stack frame size of 2272 bytes in function 'hexium_probe'
      [-Werror,-Wframe-larger-than=]
static int hexium_probe(struct saa7146_dev *dev)
           ^
drivers/media/pci/saa7146/hexium_gemini.c:257:12: error: stack frame size of 2304 bytes in function 'hexium_attach'
      [-Werror,-Wframe-larger-than=]
static int hexium_attach(struct saa7146_dev *dev, struct saa7146_pci_extension_data *info)
           ^

This one happens regardless of KASAN, and the problem is that a
constructor to initialize a dynamically allocated structure leads
to a copy of that structure on the stack, whereas gcc initializes
it in place.

Link: https://bugs.llvm.org/show_bug.cgi?id=40776
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: fix checkpatch warnings]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/media/pci/saa7146/hexium_gemini.c
drivers/media/pci/saa7146/hexium_orion.c

index 5817d9c..6d8e4af 100644 (file)
@@ -270,9 +270,8 @@ static int hexium_attach(struct saa7146_dev *dev, struct saa7146_pci_extension_d
        /* enable i2c-port pins */
        saa7146_write(dev, MC1, (MASK_08 | MASK_24 | MASK_10 | MASK_26));
 
-       hexium->i2c_adapter = (struct i2c_adapter) {
-               .name = "hexium gemini",
-       };
+       strscpy(hexium->i2c_adapter.name, "hexium gemini",
+               sizeof(hexium->i2c_adapter.name));
        saa7146_i2c_adapter_prepare(dev, &hexium->i2c_adapter, SAA7146_I2C_BUS_BIT_RATE_480);
        if (i2c_add_adapter(&hexium->i2c_adapter) < 0) {
                DEB_S("cannot register i2c-device. skipping.\n");
index 0a05176..a794f9e 100644 (file)
@@ -231,9 +231,8 @@ static int hexium_probe(struct saa7146_dev *dev)
        saa7146_write(dev, DD1_STREAM_B, 0x00000000);
        saa7146_write(dev, MC2, (MASK_09 | MASK_25 | MASK_10 | MASK_26));
 
-       hexium->i2c_adapter = (struct i2c_adapter) {
-               .name = "hexium orion",
-       };
+       strscpy(hexium->i2c_adapter.name, "hexium orion",
+               sizeof(hexium->i2c_adapter.name));
        saa7146_i2c_adapter_prepare(dev, &hexium->i2c_adapter, SAA7146_I2C_BUS_BIT_RATE_480);
        if (i2c_add_adapter(&hexium->i2c_adapter) < 0) {
                DEB_S("cannot register i2c-device. skipping.\n");