889c695d41
Deferred struct page init is needed only on systems with large amount of
physical memory to improve boot performance. 32-bit systems do not
benefit from this feature.
Jiri reported a problem where deferred struct pages do not work well with
x86-32:
[ 0.035162] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[ 0.035725] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.036269] Initializing CPU#0
[ 0.036513] Initializing HighMem for node 0 (00036ffe:0007ffe0)
[ 0.038459] page:f6780000 is uninitialized and poisoned
[ 0.038460] raw: ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff
[ 0.039509] page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page))
[ 0.040038] ------------[ cut here ]------------
[ 0.040399] kernel BUG at include/linux/page-flags.h:293!
[ 0.040823] invalid opcode: 0000 [#1] SMP PTI
[ 0.041166] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc1_pt_jiri #9
[ 0.041694] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
[ 0.042496] EIP: free_highmem_page+0x64/0x80
[ 0.042839] Code: 13 46 d8 c1 e8 18 5d 83 e0 03 8d 04 c0 c1 e0 06 ff 80 ec 5f 44 d8 c3 8d b4 26 00 00 00 00 ba 08 65 28 d8 89 d8 e8 fc 71 02 00 <0f> 0b 8d 76 00 8d bc 27 00 00 00 00 ba d0 b1 26 d8 89 d8 e8 e4 71
[ 0.044338] EAX: 0000003c EBX: f6780000 ECX: 00000000 EDX: d856cbe8
[ 0.044868] ESI: 0007ffe0 EDI: d838df20 EBP: d838df00 ESP: d838defc
[ 0.045372] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210086
[ 0.045913] CR0: 80050033 CR2: 00000000 CR3: 18556000 CR4: 00040690
[ 0.046413] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[ 0.046913] DR6: fffe0ff0 DR7: 00000400
[ 0.047220] Call Trace:
[ 0.047419] add_highpages_with_active_regions+0xbd/0x10d
[ 0.047854] set_highmem_pages_init+0x5b/0x71
[ 0.048202] mem_init+0x2b/0x1e8
[ 0.048460] start_kernel+0x1d2/0x425
[ 0.048757] i386_start_kernel+0x93/0x97
[ 0.049073] startup_32_smp+0x164/0x168
[ 0.049379] Modules linked in:
[ 0.049626] ---[ end trace 337949378db0abbb ]---
We free highmem pages before their struct pages are initialized:
mem_init()
set_highmem_pages_init()
add_highpages_with_active_regions()
free_highmem_page()
.. Access uninitialized struct page here..
Because there is no reason to have this feature on 32-bit systems, just
disable it.
Link: http://lkml.kernel.org/r/20180831150506.31246-1-pavel.tatashin@microsoft.com
Fixes:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.