On Tue, Mar 28, 2023 at 5:58 AM Jaewon Kim <jaewon31.kim@xxxxxxxxxxx> 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@xxxxxxxxxxx> 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@xxxxxxxxxx> thanks -john