From: Haren Myneni Date: Mon, 12 Dec 2005 08:37:39 +0000 (-0800) Subject: [PATCH] fix in __alloc_bootmem_core() when there is no free page in first node's... X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=66d43e98ea6ff291cd4e524386bfb99105feb180;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [PATCH] fix in __alloc_bootmem_core() when there is no free page in first node's memory Hitting BUG_ON() in __alloc_bootmem_core() when there is no free page available in the first node's memory. For the case of kdump on PPC64 (Power 4 machine), the captured kernel is used two memory regions - memory for TCE tables (tce-base and tce-size at top of RAM and reserved) and captured kernel memory region (crashk_base and crashk_size). Since we reserve the memory for the first node, we should be returning from __alloc_bootmem_core() to search for the next node (pg_dat). Currently, find_next_zero_bit() is returning the n^th bit (eidx) when there is no free page. Then, test_bit() is failed since we set 0xff only for the actual size initially (init_bootmem_core()) even though rounded up to one page for bdata->node_bootmem_map. We are hitting the BUG_ON after failing to enter second "for" loop. Signed-off-by: Haren Myneni Cc: Andy Whitcroft Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/bootmem.c b/mm/bootmem.c index e8c567177dcf..16b9465eb4eb 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -204,6 +204,8 @@ restart_scan: unsigned long j; i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i); i = ALIGN(i, incr); + if (i >= eidx) + break; if (test_bit(i, bdata->node_bootmem_map)) continue; for (j = i + 1; j < i + areasize; ++j) {