net: qla3xxx: Remove overflowing shift statement
authorNathan Chancellor <natechancellor@gmail.com>
Sat, 13 Oct 2018 02:14:58 +0000 (19:14 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 13 Nov 2018 19:16:48 +0000 (11:16 -0800)
[ Upstream commit 8c3bf9b62b667456a57aefcf1689e826df146159 ]

Clang currently warns:

drivers/net/ethernet/qlogic/qla3xxx.c:384:24: warning: signed shift
result (0xF00000000) requires 37 bits to represent, but 'int' only has
32 bits [-Wshift-overflow]
                    ((ISP_NVRAM_MASK << 16) | qdev->eeprom_cmd_data));
                      ~~~~~~~~~~~~~~ ^  ~~
1 warning generated.

The warning is certainly accurate since ISP_NVRAM_MASK is defined as
(0x000F << 16) which is then shifted by 16, resulting in 64424509440,
well above UINT_MAX.

Given that this is the only location in this driver where ISP_NVRAM_MASK
is shifted again, it seems likely that ISP_NVRAM_MASK was originally
defined without a shift and during the move of the shift to the
definition, this statement wasn't properly removed (since ISP_NVRAM_MASK
is used in the statenent right above this). Only the maintainers can
confirm this since this statment has been here since the driver was
first added to the kernel.

Link: https://github.com/ClangBuiltLinux/linux/issues/127
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/net/ethernet/qlogic/qla3xxx.c

index b09a6b80d10719c967994ed54618c50e25fdec0f..355c5fb802cd71e10474f8dc2c4334cc5e3471a0 100644 (file)
@@ -380,8 +380,6 @@ static void fm93c56a_select(struct ql3_adapter *qdev)
 
        qdev->eeprom_cmd_data = AUBURN_EEPROM_CS_1;
        ql_write_nvram_reg(qdev, spir, ISP_NVRAM_MASK | qdev->eeprom_cmd_data);
-       ql_write_nvram_reg(qdev, spir,
-                          ((ISP_NVRAM_MASK << 16) | qdev->eeprom_cmd_data));
 }
 
 /*