Re: [PATCH] swap: Check nrexceptional of swap cache before being freed

[Huang, Ying]

Matthew Wilcox <willy@xxxxxxxxxxxxx> writes:

> On Wed, Jan 20, 2021 at 03:27:11PM +0800, Huang Ying wrote:
>> To catch the error in updating the swap cache shadow entries or their count.
>
> I just resent a patch that removes nrexceptional tracking.
>
> Can you use !mapping_empty() instead?

Sure.  Will use that in the next version.

Best Regards,
Huang, Ying

>>  void exit_swap_address_space(unsigned int type)
>>  {
>> -	kvfree(swapper_spaces[type]);
>> +	int i;
>> +	struct address_space *spaces = swapper_spaces[type];
>> +
>> +	for (i = 0; i < nr_swapper_spaces[type]; i++)
>> +		VM_BUG_ON(spaces[i].nrexceptional);
>> +	kvfree(spaces);
>>  	nr_swapper_spaces[type] = 0;
>>  	swapper_spaces[type] = NULL;
>>  }
>> -- 
>> 2.29.2
>> 
>>