-Return type of 'qe_muram_alloc' is 'unsigned long', That Was trying to
assigned in ucc_fast_tx_virtual_fifo_base_offset and
ucc_fast_rx_virtual_fifo_base_offset. It will work on 32-bit architectures
But data can be loss on 64-bit architectures if 'qe_muram_alloc' will
return greater then MAX value of 'unsigned int'.
-Passing value in IS_ERR_VALUE() is wrong, as they pass an 'unsigned int'
into a function, It will through this compilation warning.
"
include/linux/err.h:21:49: warning: cast to pointer from integer of different
size [-Wint-to-pointer-cast]
#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned
long)-MAX_ERRNO)
^
include/linux/compiler.h:170:42: note: in definition of macro ‘unlikely’
# define unlikely(x) __builtin_expect(!!(x), 0)
"
-Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'unsigned int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.
However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.
Signed-off-by: Arvind Yadav <arvind.yadav...@gmail.com>
---
drivers/soc/fsl/qe/ucc_fast.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/drivers/soc/fsl/qe/ucc_fast.c b/drivers/soc/fsl/qe/ucc_fast.c
index a768931..208b198 100644
--- a/drivers/soc/fsl/qe/ucc_fast.c
+++ b/drivers/soc/fsl/qe/ucc_fast.c
@@ -141,6 +141,7 @@ int ucc_fast_init(struct ucc_fast_info * uf_info, struct
ucc_fast_private ** ucc
struct ucc_fast __iomem *uf_regs;
u32 gumr;
int ret;
+ unsigned long ret_muram;
if (!uf_info)
return -EINVAL;
@@ -265,28 +266,34 @@ int ucc_fast_init(struct ucc_fast_info * uf_info, struct
ucc_fast_private ** ucc
gumr |= uf_info->mode;
out_be32(&uf_regs->gumr, gumr);
- /* Allocate memory for Tx Virtual Fifo */
- uccf->ucc_fast_tx_virtual_fifo_base_offset =
- qe_muram_alloc(uf_info->utfs, UCC_FAST_VIRT_FIFO_REGS_ALIGNMENT);
- if (IS_ERR_VALUE(uccf->ucc_fast_tx_virtual_fifo_base_offset)) {
+ ret_muram =
+ qe_muram_alloc(uf_info->utfs,
+ UCC_FAST_VIRT_FIFO_REGS_ALIGNMENT);
+
+ if (IS_ERR_VALUE(ret_muram)) {
printk(KERN_ERR "%s: cannot allocate MURAM for TX FIFO\n",
__func__);
uccf->ucc_fast_tx_virtual_fifo_base_offset = 0;
ucc_fast_free(uccf);
return -ENOMEM;
+ } else {
+ /* Allocate memory for Tx Virtual Fifo */
+ uccf->ucc_fast_tx_virtual_fifo_base_offset = (u32)ret_muram;
}
- /* Allocate memory for Rx Virtual Fifo */
- uccf->ucc_fast_rx_virtual_fifo_base_offset =
+ ret_muram =
qe_muram_alloc(uf_info->urfs +
UCC_FAST_RECEIVE_VIRTUAL_FIFO_SIZE_FUDGE_FACTOR,
UCC_FAST_VIRT_FIFO_REGS_ALIGNMENT);
- if (IS_ERR_VALUE(uccf->ucc_fast_rx_virtual_fifo_base_offset)) {
+ if (IS_ERR_VALUE(ret_muram)) {
printk(KERN_ERR "%s: cannot allocate MURAM for RX FIFO\n",
__func__);
uccf->ucc_fast_rx_virtual_fifo_base_offset = 0;
ucc_fast_free(uccf);
return -ENOMEM;
+ } else {
+ /* Allocate memory for Rx Virtual Fifo */
+ uccf->ucc_fast_rx_virtual_fifo_base_offset = (u32)ret_muram;
}
/* Set Virtual Fifo registers */
--
1.9.1
