On 2017/1/24 18:23, Michal Hocko wrote:
> On Mon 23-01-17 20:07:00, zhongjiang wrote:
>> From: zhong jiang <zhongjiang@xxxxxxxxxx>
>>
>> Recently, I've found cases in which ioremap_page_range was used
>> incorrectly, in external modules, leading to crashes. This can be
>> partly attributed to the fact that ioremap_page_range is lower-level,
>> with fewer protections, as compared to the other functions that an
>> external module would typically call. Those include:
>>
>> ioremap_cache
>> ioremap_nocache
>> ioremap_prot
>> ioremap_uc
>> ioremap_wc
>> ioremap_wt
>>
>> ...each of which wraps __ioremap_caller, which in turn provides a
>> safer way to achieve the mapping.
>>
>> Therefore, stop EXPORT-ing ioremap_page_range.
>>
>> Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
>> Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
>> Suggested-by: John Hubbard <jhubbard@xxxxxxxxxx>
> git grep says that there are few direct users of this API in the tree.
> Have you checked all of them? The export has been added by 81e88fdc432a
> ("ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification
> type support").
I have checked more than one times. and John also have looked through the whole own kernel.
Thanks
zhongjiang
> Other than that this looks reasonably to me.
>
>> ---
>> lib/ioremap.c | 1 -
>> 1 file changed, 1 deletion(-)
>>
>> diff --git a/lib/ioremap.c b/lib/ioremap.c
>> index 86c8911..a3e14ce 100644
>> --- a/lib/ioremap.c
>> +++ b/lib/ioremap.c
>> @@ -144,4 +144,3 @@ int ioremap_page_range(unsigned long addr,
>>
>> return err;
>> }
>> -EXPORT_SYMBOL_GPL(ioremap_page_range);
>> --
>> 1.8.3.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
