releases/4.14.93/genwqe-fix-size-check.patch

   1 From fdd669684655c07dacbdb0d753fd13833de69a33 Mon Sep 17 00:00:00 2001
   2 From: Christian Borntraeger <borntraeger@de.ibm.com>
   3 Date: Wed, 12 Dec 2018 14:45:18 +0100
   4 Subject: genwqe: Fix size check
   5
   6 From: Christian Borntraeger <borntraeger@de.ibm.com>
   7
   8 commit fdd669684655c07dacbdb0d753fd13833de69a33 upstream.
   9
  10 Calling the test program genwqe_cksum with the default buffer size of
  11 2MB triggers the following kernel warning on s390:
  12
  13 WARNING: CPU: 30 PID: 9311 at mm/page_alloc.c:3189 __alloc_pages_nodemask+0x45c/0xbe0
  14 CPU: 30 PID: 9311 Comm: genwqe_cksum Kdump: loaded Not tainted 3.10.0-957.el7.s390x #1
  15 task: 00000005e5d13980 ti: 00000005e7c6c000 task.ti: 00000005e7c6c000
  16 Krnl PSW : 0704c00180000000 00000000002780ac (__alloc_pages_nodemask+0x45c/0xbe0)
  17            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
  18 Krnl GPRS: 00000000002932b8 0000000000b73d7c 0000000000000010 0000000000000009
  19            0000000000000041 00000005e7c6f9b8 0000000000000001 00000000000080d0
  20            0000000000000000 0000000000b70500 0000000000000001 0000000000000000
  21            0000000000b70528 00000000007682c0 0000000000277df2 00000005e7c6f9a0
  22 Krnl Code: 000000000027809e: de7195001000       ed      1280(114,%r9),0(%r1)
  23            00000000002780a4: a774fead           brc     7,277dfe
  24           #00000000002780a8: a7f40001           brc     15,2780aa
  25           >00000000002780ac: 92011000           mvi     0(%r1),1
  26            00000000002780b0: a7f4fea7           brc     15,277dfe
  27            00000000002780b4: 9101c6b6           tm      1718(%r12),1
  28            00000000002780b8: a784ff3a           brc     8,277f2c
  29            00000000002780bc: a7f4fe2e           brc     15,277d18
  30 Call Trace:
  31 ([<0000000000277df2>] __alloc_pages_nodemask+0x1a2/0xbe0)
  32  [<000000000013afae>] s390_dma_alloc+0xfe/0x310
  33  [<000003ff8065f362>] __genwqe_alloc_consistent+0xfa/0x148 [genwqe_card]
  34  [<000003ff80658f7a>] genwqe_mmap+0xca/0x248 [genwqe_card]
  35  [<00000000002b2712>] mmap_region+0x4e2/0x778
  36  [<00000000002b2c54>] do_mmap+0x2ac/0x3e0
  37  [<0000000000292d7e>] vm_mmap_pgoff+0xd6/0x118
  38  [<00000000002b081c>] SyS_mmap_pgoff+0xdc/0x268
  39  [<00000000002b0a34>] SyS_old_mmap+0x8c/0xb0
  40  [<000000000074e518>] sysc_tracego+0x14/0x1e
  41  [<000003ffacf87dc6>] 0x3ffacf87dc6
  42
  43 turns out the check in __genwqe_alloc_consistent uses "> MAX_ORDER"
  44 while the mm code uses ">= MAX_ORDER". Fix genwqe.
  45
  46 Cc: stable@vger.kernel.org
  47 Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
  48 Signed-off-by: Frank Haverkamp <haver@linux.vnet.ibm.com>
  49 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  50
  51 ---
  52  drivers/misc/genwqe/card_utils.c |    2 +-
  53  1 file changed, 1 insertion(+), 1 deletion(-)
  54
  55 --- a/drivers/misc/genwqe/card_utils.c
  56 +++ b/drivers/misc/genwqe/card_utils.c
  57 @@ -217,7 +217,7 @@ u32 genwqe_crc32(u8 *buff, size_t len, u
  58  void *__genwqe_alloc_consistent(struct genwqe_dev *cd, size_t size,
  59                                dma_addr_t *dma_handle)
  60  {
  61 -       if (get_order(size) > MAX_ORDER)
  62 +       if (get_order(size) >= MAX_ORDER)
  63                 return NULL;
  64
  65         return dma_zalloc_coherent(&cd->pci_dev->dev, size, dma_handle,