[PATCH v3] mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems

[PATCH v3] mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems

[Daniel Golle]

A compiler warning related to sizeof(int) != 8 when calling do_div()
is triggered when building on 32-bit platforms.
Address this by using integer types having a well-defined size.

Fixes: 3ce485803da1 ("mtd: ubi: provide NVMEM layer over UBI volumes")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
v3: use size_t also for 'to_read' variable to avoid truncation
    (no problem in practise beyond the compiler warning)
v2: use size_t for 'bytes_left' variable to match parameter type

 drivers/mtd/ubi/nvmem.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/nvmem.c b/drivers/mtd/ubi/nvmem.c
index b7a93c495d172..8aeb9c428e510 100644
--- a/drivers/mtd/ubi/nvmem.c
+++ b/drivers/mtd/ubi/nvmem.c
@@ -23,9 +23,12 @@ struct ubi_nvmem {
 static int ubi_nvmem_reg_read(void *priv, unsigned int from,
 			      void *val, size_t bytes)
 {
-	int err = 0, lnum = from, offs, bytes_left = bytes, to_read;
+	size_t to_read, bytes_left = bytes;
 	struct ubi_nvmem *unv = priv;
 	struct ubi_volume_desc *desc;
+	uint32_t offs;
+	uint64_t lnum = from;
+	int err = 0;
 
 	desc = ubi_open_volume(unv->ubi_num, unv->vol_id, UBI_READONLY);
 	if (IS_ERR(desc))
-- 
2.44.0

Re: [PATCH v3] mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems

[Zhihao Cheng]

在 2024/2/29 11:47, Daniel Golle 写道:
> A compiler warning related to sizeof(int) != 8 when calling do_div()
> is triggered when building on 32-bit platforms.
> Address this by using integer types having a well-defined size.
> 
> Fixes: 3ce485803da1 ("mtd: ubi: provide NVMEM layer over UBI volumes")
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> ---
> v3: use size_t also for 'to_read' variable to avoid truncation
>      (no problem in practise beyond the compiler warning)
> v2: use size_t for 'bytes_left' variable to match parameter type
> 
>   drivers/mtd/ubi/nvmem.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 

Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
> diff --git a/drivers/mtd/ubi/nvmem.c b/drivers/mtd/ubi/nvmem.c
> index b7a93c495d172..8aeb9c428e510 100644
> --- a/drivers/mtd/ubi/nvmem.c
> +++ b/drivers/mtd/ubi/nvmem.c
> @@ -23,9 +23,12 @@ struct ubi_nvmem {
>   static int ubi_nvmem_reg_read(void *priv, unsigned int from,
>   			      void *val, size_t bytes)
>   {
> -	int err = 0, lnum = from, offs, bytes_left = bytes, to_read;
> +	size_t to_read, bytes_left = bytes;
>   	struct ubi_nvmem *unv = priv;
>   	struct ubi_volume_desc *desc;
> +	uint32_t offs;
> +	uint64_t lnum = from;
> +	int err = 0;
>   
>   	desc = ubi_open_volume(unv->ubi_num, unv->vol_id, UBI_READONLY);
>   	if (IS_ERR(desc))
> 

Re: [PATCH v3] mtd: ubi: fix NVMEM over UBI volumes on 32-bit systems

[Randy Dunlap]

On 2/28/24 19:47, Daniel Golle wrote:
> A compiler warning related to sizeof(int) != 8 when calling do_div()
> is triggered when building on 32-bit platforms.
> Address this by using integer types having a well-defined size.
> 
> Fixes: 3ce485803da1 ("mtd: ubi: provide NVMEM layer over UBI volumes")
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> ---
> v3: use size_t also for 'to_read' variable to avoid truncation
>     (no problem in practise beyond the compiler warning)
> v2: use size_t for 'bytes_left' variable to match parameter type
> 
>  drivers/mtd/ubi/nvmem.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 

Works for me. Thanks.

Tested-by: Randy Dunlap <rdunlap@infradead.org>

-- 
#Randy