RE: [PATCH] dma-buf/heaps: c9e8440eca61 staging: ion: Fix overflow and list bugs in system heap:

[김재원 <jaewon31.kim@samsung.com>]

> 
> 
>--------- Original Message ---------
>Sender : John Stultz <jstultz@google.com>
>Date : 2023-03-29 03:26 (GMT+9)
>Title : Re: [PATCH] dma-buf/heaps: c9e8440eca61 staging: ion: Fix overflow and list bugs in system heap:
> 
>On Tue, Mar 28, 2023 at 5:58 AM Jaewon Kim <jaewon31.kim@samsung.com> wrote:
>>
>> Normal free:212600kB min:7664kB low:57100kB high:106536kB
>>   reserved_highatomic:4096KB active_anon:276kB inactive_anon:180kB
>>   active_file:1200kB inactive_file:0kB unevictable:2932kB
>>   writepending:0kB present:4109312kB managed:3689488kB mlocked:2932kB
>>   pagetables:13600kB bounce:0kB free_pcp:0kB local_pcp:0kB
>>   free_cma:200844kB
>> Out of memory and no killable processes...
>> Kernel panic - not syncing: System is deadlocked on memory
>>
>> An OoM panic was reported, there were only native processes which are
>> non-killable as OOM_SCORE_ADJ_MIN.
>>
>> After looking into the dump, I've found the dma-buf system heap was
>> trying to allocate a huge size. It seems to be a signed negative value.
>>
>> dma_heap_ioctl_allocate(inline)
>>     |  heap_allocation = 0xFFFFFFC02247BD38 -> (
>>     |    len = 0xFFFFFFFFE7225100,
>>
>> Actually the old ion system heap had policy which does not allow that
>> huge size with commit c9e8440eca61 ("staging: ion: Fix overflow and list
>> bugs in system heap"). We need this change again. Single allocation
>> should not be bigger than half of all memory.
>>
>> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
>
>Hey,
>  Thanks so much for sending this out! Looks reasonable to me, the
>only issue is the commit subject line could be a bit better.
>
>Maybe instead:
>  "dma-buf/heaps: system_heap: Avoid DoS by limiting single
>allocations to half of all memory"
>
>Otherwise,
>Acked-by: John Stultz <jstultz@google.com>
>
>thanks
>-john
>

Hello John

Thank you for your Acked. and the subject thing.
Maybe I was in a hurry, I did not check it.

I am going to take yours

"dma-buf/heaps: system_heap: Avoid DoS by limiting single
allocations to half of all memory"

By the way let me talk with T.J.

Thank you
Jaewon Kim