On Thu, Jun 28, 2012 at 02:34:29PM -0700, David Rientjes wrote: >On Thu, 28 Jun 2012, Gavin Shan wrote: > >> >> +{ >> >> + unsigned long size = SECTIONS_PER_ROOT * >> >> + sizeof(struct mem_section); >> >> + >> >> + if (!section) >> >> + return; >> >> + >> >> + if (slab_is_available()) >> >> + kfree(section); >> >> + else >> >> + free_bootmem_node(NODE_DATA(nid), >> >> + virt_to_phys(section), size); >> > >> >Did you check what happens here if !node_state(nid, N_HIGH_MEMORY)? >> > >> >> I'm sorry that I'm not catching your point. Please explain for more >> if necessary. >> > >I'm asking specifically about the free_bootmem_node(NODE_DATA(nid), ...). > Thanks for pointing it out, David. >If this section was allocated in sparse_index_alloc() before >slab_is_available() with alloc_bootmem_node() and nid is not in >N_HIGH_MEMORY, will alloc_bootmem_node() fallback to any node or return >NULL? > Yes, you're right that bootmem allocator will try other nodes if the specified node can't accomodate the memory allocation. So it's not safe to free memory by free_bootmem_node(). >If it falls back to any node, is it safe to try to free that section by >passing NODE_DATA(nid) here when it wasn't allocated on that nid? > I think free_bootmem() should be used here :-) Thanks, Gavin -- 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>