On 2016/3/31 17:30, Michal Hocko wrote: > On Thu 31-03-16 17:16:00, Xishi Qiu wrote: >> It triggers a lot of ooms, but there is enough memory(many large blocks). >> And at last "Kernel panic - not syncing: Out of memory and no killable processes..." >> >> I find almost the every call trace include "pagefault_out_of_memory" and "gfp_mask=0x0". >> If it does oom, why not it triger in mm core path? > > It seems that somebody in the page fault path has returned with > VM_FAULT_OOM without invoking the page allocator and kept returning the > same error until there is nothing killable and so the oom killer panics. > > [...] >> <4>[63651.040374s][pid:2912,cpu3,sh]DMA free:550600kB min:5244kB low:27580kB high:28892kB active_anon:343060kB inactive_anon:1224kB active_file:107596kB inactive_file:465156kB unevictable:1040kB isolated(anon):0kB isolated(file):0kB present:2016252kB managed:1720040kB mlocked:1040kB dirty:40kB writeback:0kB mapped:200420kB shmem:1312kB slab_reclaimable:27048kB slab_unreclaimable:73300kB kernel_stack:15248kB pagetables:14484kB unstable:0kB bounce:0kB free_cma:30896kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no > > This is rather weird. DMA zone with 2GB? What kind of architecture is > this? Hi Michal, It's arm64, so DMA is [0-4G], and Normal is [4G-] Is that something wrong with the RAM hardware, then trigger the problem? Thanks, Xishi Qiu -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>