• Hariom Panthi's avatar
    mm: vmalloc: dump page owner info if page is already mapped · 21e516b9
    Hariom Panthi authored
    In vmap_pte_range, BUG_ON is called when page is already mapped,
    It doesn't give enough information to debug further.
    Dumping page owner information alongwith BUG_ON will be more useful
    in case of multiple page mapping.
    
    Example:
    [   14.552875] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b923
    [   14.553440] flags: 0xbffff0000000000(node=0|zone=2|lastcpupid=0x3ffff)
    [   14.554001] page_type: 0xffffffff()
    [   14.554783] raw: 0bffff0000000000 0000000000000000 dead000000000122 0000000000000000
    [   14.555230] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
    [   14.555768] page dumped because: remapping already mapped page
    [   14.556172] page_owner tracks the page as allocated
    [   14.556482] page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 80, tgid 80 (insmod), ts 14552004992, free_ts 0
    [   14.557286]  prep_new_page+0xa8/0x10c
    [   14.558052]  get_page_from_freelist+0x7f8/0x1248
    [   14.558298]  __alloc_pages+0x164/0x2b4
    [   14.558514]  alloc_pages_mpol+0x88/0x230
    [   14.558904]  alloc_pages+0x4c/0x7c
    [   14.559157]  load_module+0x74/0x1af4
    [   14.559361]  __do_sys_init_module+0x190/0x1fc
    [   14.559615]  __arm64_sys_init_module+0x1c/0x28
    [   14.559883]  invoke_syscall+0x44/0x108
    [   14.560109]  el0_svc_common.constprop.0+0x40/0xe0
    [   14.560371]  do_el0_svc_compat+0x1c/0x34
    [   14.560600]  el0_svc_compat+0x2c/0x80
    [   14.560820]  el0t_32_sync_handler+0x90/0x140
    [   14.561040]  el0t_32_sync+0x194/0x198
    [   14.561329] page_owner free stack trace missing
    [   14.562049] ------------[ cut here ]------------
    [   14.562314] kernel BUG at mm/vmalloc.c:113!
    
    Link: https://lkml.kernel.org/r/20240424111838.3782931-2-hariom1.p@samsung.comSigned-off-by: default avatarHariom Panthi <hariom1.p@samsung.com>
    Cc: Christoph Hellwig <hch@infradead.org>
    Cc: Lorenzo Stoakes <lstoakes@gmail.com>
    Cc: Maninder Singh <maninder1.s@samsung.com>
    Cc: Oscar Salvador <osalvador@suse.de>
    Cc: Rohit Thapliyal <r.thapliyal@samsung.com>
    Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
    Cc: Vlastimil Babka <vbabka@suse.cz>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    21e516b9
vmalloc.c 131 KB