Subject: Re: [PATCH]->[PATCH v2] kgdb: Removed kmalloc returned value cast

From: "tiejun.chen" <[email-masked]>
Date: Mon, 11 Mar 2013 18:14:29 +0800

On 03/11/2013 09:33 AM, tiejun.chen wrote:
> On 03/11/2013 06:39 AM, Alex Grad wrote:
>> While at it, check kmalloc return value.
>>
>> Signed-off-by: Alex Grad <[email-masked]>
>> ---
>>   arch/powerpc/kernel/kgdb.c |    5 ++++-
>>   1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
>> index 5ca82cd..9e81dd8 100644
>> --- a/arch/powerpc/kernel/kgdb.c
>> +++ b/arch/powerpc/kernel/kgdb.c
>> @@ -159,7 +159,10 @@ static int kgdb_singlestep(struct pt_regs *regs)
>>       if (user_mode(regs))
>>           return 0;
>>
>> -    backup_current_thread_info = (struct thread_info *)kmalloc(sizeof(struct
>> thread_info), GFP_KERNEL);
>> +    backup_current_thread_info = kmalloc(sizeof(struct thread_info),
>> GFP_KERNEL);
>> +    if (!backup_current_thread_info)
>> +        return -ENOMEM;
>
> I already send a kgdb patchset in "[v3][PATCH 6/6] powerpc/kgdb: remove copying
> the thread_info" to remove these stuff since its unnecessary to copy current
> thread_info now.

I guess that patchset needs to be reviewed with more time and I also think I can 
leave this copying to be compatible for other platforms in the future, but we 
really should fix this problem I introduced right now. So I'd like to fix this 
with DEFINE_PER_CPU.

I send a patch, "powerpc/kgdb: use DEFINE_PER_CPU to allocate kgdb's 
thread_info", so please take a look at if that version is fine to every one.

Any comments are appreciated.

BTW, I will update that kgdb patchset with this change to resend.

Tiejun