Re: [RFC PATCH 0/2] improve vmalloc allocation

From: Shuah Khan
Date: Tue Oct 23 2018 - 16:50:58 EST


On 10/23/2018 02:09 PM, Matthew Wilcox wrote:
> On Tue, Oct 23, 2018 at 01:48:32PM -0600, Shuah Khan wrote:
>> On 10/23/2018 01:30 PM, Joel Fernandes wrote:
>>> On Tue, Oct 23, 2018 at 11:13:36AM -0600, Shuah Khan wrote:
>>>> I like this proposal. I think we will open up lot of test opportunities with
>>>> this approach.
>>>>
>>>> Maybe we can use this stress test as a pilot and see where it takes us.
>>>
>>> I am a bit worried that such an EXPORT_SYMBOL_KSELFTEST mechanism can be abused by
>>> out-of-tree module writers to call internal functionality.
>>
>> That is valid concern to consider before we go forward with the proposal.
>>
>> We could wrap EXPORT_SYMBOL_KSELFTEST this in an existing debug option. This could
>> be fine grained for each sub-system for its debug option. We do have a few of these
>> now
>
> This all seems far more complicated than my proposed solution.
>

Not sure if it that complicated. But it is more involved. It dies have the
advantage of fitting in with the rest of the debug/test type framework we
already have.

The option you proposed sounds simpler, however it sounds a bit adhoc to me.

In any case I went looking for EXPORT_SYMBOL defines and found them in

tools/include/asm/export.h
tools/include/linux/export.h
tools/virtio/linux/export.h

selftests/powerpc/copyloops/asm/export.h
selftests/powerpc/stringloops/asm/export.h

thanks,
-- Shuah