fdd6696846
Calling the test program genwqe_cksum with the default buffer size of 2MB triggers the following kernel warning on s390: WARNING: CPU: 30 PID: 9311 at mm/page_alloc.c:3189 __alloc_pages_nodemask+0x45c/0xbe0 CPU: 30 PID: 9311 Comm: genwqe_cksum Kdump: loaded Not tainted 3.10.0-957.el7.s390x #1 task: 00000005e5d13980 ti: 00000005e7c6c000 task.ti: 00000005e7c6c000 Krnl PSW : 0704c00180000000 00000000002780ac (__alloc_pages_nodemask+0x45c/0xbe0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3 Krnl GPRS: 00000000002932b8 0000000000b73d7c 0000000000000010 0000000000000009 0000000000000041 00000005e7c6f9b8 0000000000000001 00000000000080d0 0000000000000000 0000000000b70500 0000000000000001 0000000000000000 0000000000b70528 00000000007682c0 0000000000277df2 00000005e7c6f9a0 Krnl Code: 000000000027809e: de7195001000 ed 1280(114,%r9),0(%r1) 00000000002780a4: a774fead brc 7,277dfe #00000000002780a8: a7f40001 brc 15,2780aa >00000000002780ac: 92011000 mvi 0(%r1),1 00000000002780b0: a7f4fea7 brc 15,277dfe 00000000002780b4: 9101c6b6 tm 1718(%r12),1 00000000002780b8: a784ff3a brc 8,277f2c 00000000002780bc: a7f4fe2e brc 15,277d18 Call Trace: ([<0000000000277df2>] __alloc_pages_nodemask+0x1a2/0xbe0) [<000000000013afae>] s390_dma_alloc+0xfe/0x310 [<000003ff8065f362>] __genwqe_alloc_consistent+0xfa/0x148 [genwqe_card] [<000003ff80658f7a>] genwqe_mmap+0xca/0x248 [genwqe_card] [<00000000002b2712>] mmap_region+0x4e2/0x778 [<00000000002b2c54>] do_mmap+0x2ac/0x3e0 [<0000000000292d7e>] vm_mmap_pgoff+0xd6/0x118 [<00000000002b081c>] SyS_mmap_pgoff+0xdc/0x268 [<00000000002b0a34>] SyS_old_mmap+0x8c/0xb0 [<000000000074e518>] sysc_tracego+0x14/0x1e [<000003ffacf87dc6>] 0x3ffacf87dc6 turns out the check in __genwqe_alloc_consistent uses "> MAX_ORDER" while the mm code uses ">= MAX_ORDER". Fix genwqe. Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Frank Haverkamp <haver@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.