Re: [PATCH] x86: efi: Replace GFP_ATOMIC with GFP_KERNEL in efi_query_variable_store
From: Ard Biesheuvel
Date: Tue Feb 13 2018 - 13:40:54 EST
On 13 February 2018 at 18:07, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
> * Jia-Ju Bai <baijiaju1990@xxxxxxxxx> wrote:
>
>> The function kzalloc here is not called in atomic context.
>> If nonblocking in efi_query_variable_store is true,
>> namely it is in atomic context, efi_query_variable_store will return before
>> this kzalloc is called.
>> Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.
>>
>> This is found by a static analysis tool named DCNS written by myself.
>>
>> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
>> ---
>> arch/x86/platform/efi/quirks.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
>> index 8a99a2e..b6dcb52 100644
>> --- a/arch/x86/platform/efi/quirks.c
>> +++ b/arch/x86/platform/efi/quirks.c
>> @@ -177,7 +177,7 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size,
>> * that by attempting to use more space than is available.
>> */
>> unsigned long dummy_size = remaining_size + 1024;
>> - void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
>> + void *dummy = kzalloc(dummy_size, GFP_KERNEL);
>
> Looks good to me!
>
> Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
>
Queued in linux-efi/next
Thanks all.