1. 11 Jul, 2023 1 commit
    • gaoming's avatar
      exfat: use kvmalloc_array/kvfree instead of kmalloc_array/kfree · daf60d6c
      gaoming authored
      The call stack shown below is a scenario in the Linux 4.19 kernel.
      Allocating memory failed where exfat fs use kmalloc_array due to
      system memory fragmentation, while the u-disk was inserted without
      recognition.
      Devices such as u-disk using the exfat file system are pluggable and
      may be insert into the system at any time.
      However, long-term running systems cannot guarantee the continuity of
      physical memory. Therefore, it's necessary to address this issue.
      
      Binder:2632_6: page allocation failure: order:4,
       mode:0x6040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null)
      Call trace:
      [242178.097582]  dump_backtrace+0x0/0x4
      [242178.097589]  dump_stack+0xf4/0x134
      [242178.097598]  warn_alloc+0xd8/0x144
      [242178.097603]  __alloc_pages_nodemask+0x1364/0x1384
      [242178.097608]  kmalloc_order+0x2c/0x510
      [242178.097612]  kmalloc_order_trace+0x40/0x16c
      [242178.097618]  __kmalloc+0x360/0x408
      [242178.097624]  load_alloc_bitmap+0x160/0x284
      [242178.097628]  exfat_fill_super+0xa3c/0xe7c
      [242178.097635]  mount_bdev+0x2e8/0x3a0
      [242178.097638]  exfat_fs_mount+0x40/0x50
      [242178.097643]  mount_fs+0x138/0x2e8
      [242178.097649]  vfs_kern_mount+0x90/0x270
      [242178.097655]  do_mount+0x798/0x173c
      [242178.097659]  ksys_mount+0x114/0x1ac
      [242178.097665]  __arm64_sys_mount+0x24/0x34
      [242178.097671]  el0_svc_common+0xb8/0x1b8
      [242178.097676]  el0_svc_handler+0x74/0x90
      [242178.097681]  el0_svc+0x8/0x340
      
      By analyzing the exfat code,we found that continuous physical memory
      is not required here,so kvmalloc_array is used can solve this problem.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatargaoming <gaoming20@hihonor.com>
      Signed-off-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
      daf60d6c
  2. 09 Jul, 2023 10 commits
  3. 08 Jul, 2023 29 commits