Re: [PATCH] mm/vmalloc: warn only once when vmalloc detect invalid gfp flags

David Heidelberg
2025-11-18T00:51:25Z

On 18/11/2025 01:34, Vishal Moola (Oracle) wrote:
> On Tue, Nov 18, 2025 at 01:05:57AM +0100, David Heidelberg via B4 Relay wrote:
>> From: David Heidelberg <david@ixit.cz>
>>
>> Without WARN_ONCE, the logs get spammed immediately after the boot,
>> on devices as OnePlus 6T (Snapdragon 845).
>
> Do you have any snippets of the logs? There'll be a particularly helpful
> section that says "Unexpected gfp:"...

I didn't save it, thou I'll run the kernel with all logs again tomorrow,
what I remember it was "__GFP_ACCOUNT" in unexpected section.

>
>> Fixes: 7179b2256315 ("mm/vmalloc: warn on invalid vmalloc gfp flags")
>
> For some context, this patch begins enforcing the gfp flags passed into
> vmalloc(). If the logs are getting spammed, that means the device is
> calling vmalloc() with some unsupported gfp flag, many many times.

Yes, it was full dmesg buffer just after the boot and I think ongoing.
>
>> Signed-off-by: David Heidelberg <david@ixit.cz>
>> ---
>> I'm not 100% sure this is the right solution, but having WARN_ONCE or
>> rate limited warnings here helps a lot on devices as OnePlus 6 (sdm845).
>
> Can you check if it still happens on today's mm-new?
> I just sent a new version earlier today that also masks off
> __GFP_ACCOUNT, and had an iteration earlier that added
> __GFP_HARDWALL.

I can try tomorrow, any chance it'll bubble into next-20251118?

Thank you
David

--
David Heidelberg