[PATCH 02/30] powerpc: Use kmemdup rather than duplicating its implementation

[PATCH 02/30] powerpc: Use kmemdup rather than duplicating its implementation

[Fuqian Huang]

kmemdup is introduced to duplicate a region of memory in a neat way.
Rather than kmalloc/kzalloc + memset, which the programmer needs to
write the size twice (sometimes lead to mistakes), kmemdup improves
readability, leads to smaller code and also reduce the chances of mistakes.
Suggestion to use kmemdup rather than using kmalloc/kzalloc + memset.

Add an allocation failure check.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
---
 arch/powerpc/platforms/pseries/dlpar.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 437a74173db2..20fe7b79e09e 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -383,9 +383,10 @@ void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog)
 	struct pseries_hp_work *work;
 	struct pseries_hp_errorlog *hp_errlog_copy;
 
-	hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog),
+	hp_errlog_copy = kmemdup(hp_errlog, sizeof(struct pseries_hp_errorlog),
 				 GFP_KERNEL);
-	memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog));
+	if (!hp_errlog_copy)
+		return;
 
 	work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL);
 	if (work) {
-- 
2.11.0

Re: [PATCH 02/30] powerpc: Use kmemdup rather than duplicating its implementation

[Christophe Leroy]

Le 03/07/2019 à 15:13, Fuqian Huang a écrit :
> kmemdup is introduced to duplicate a region of memory in a neat way.
> Rather than kmalloc/kzalloc + memset, which the programmer needs to
> write the size twice (sometimes lead to mistakes), kmemdup improves
> readability, leads to smaller code and also reduce the chances of mistakes.
> Suggestion to use kmemdup rather than using kmalloc/kzalloc + memset.

s/memset/memcpy/

> 
> Add an allocation failure check.

Shouldn't this be in another patch ?

Christophe

> 
> Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
> ---
>   arch/powerpc/platforms/pseries/dlpar.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
> index 437a74173db2..20fe7b79e09e 100644
> --- a/arch/powerpc/platforms/pseries/dlpar.c
> +++ b/arch/powerpc/platforms/pseries/dlpar.c
> @@ -383,9 +383,10 @@ void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog)
>   	struct pseries_hp_work *work;
>   	struct pseries_hp_errorlog *hp_errlog_copy;
>   
> -	hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog),
> +	hp_errlog_copy = kmemdup(hp_errlog, sizeof(struct pseries_hp_errorlog),
>   				 GFP_KERNEL);
> -	memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog));
> +	if (!hp_errlog_copy)
> +		return;
>   
>   	work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL);
>   	if (work) {
>