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Stewart Smith 22f8cc6e33 drivers: of: increase MAX_RESERVED_REGIONS to 32
There are two types of memory reservations firmware can ask the kernel
to make in the device tree: static and dynamic.
See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt

If you have greater than 16 entries in /reserved-memory (as we do on
POWER9 systems) you would get this scary looking error message:
 [    0.000000] OF: reserved mem: not enough space all defined regions.

This is harmless if all your reservations are static (which with OPAL on
POWER9, they are).

It is not harmless if you have any dynamic reservations after the 16th.

In the first pass over the fdt to find reservations, the child nodes of
/reserved-memory are added to a static array in of_reserved_mem.c so that
memory can be reserved in a 2nd pass. The array has 16 entries. This is why,
on my dual socket POWER9 system, I get that error 4 times with 20 static
reservations.

We don't have a problem on ppc though, as in arch/powerpc/kernel/prom.c
we look at the new style /reserved-ranges property to do reservations,
and this logic was introduced in 0962e8004e (well before any powernv
system shipped).

A Google search shows up no occurances of that exact error message, so we're
probably safe in that no machine that people use has memory not being reserved
when it should be.

The simple fix is to bump the length of the array to 32 which "should be
enough for everyone(TM)". The simple fix of not recording static allocations
in the array would cause problems for devices with "memory-region" properties.
A more future-proof fix is likely possible, although more invasive and this
simple fix is perfectly suitable in the meantime while a more future-proof
fix is developed.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Tested-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-12 12:23:45 -05:00
arch ARC udpates for 4.14-rc4 2017-10-06 15:57:08 -07:00
block bsg-lib: fix use-after-free under memory-pressure 2017-10-04 08:35:04 -06:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto crypto: af_alg - update correct dst SGL entry 2017-09-20 17:42:42 +08:00
Documentation Merge branch 'i2c/for-current-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2017-10-07 10:07:51 -07:00
drivers drivers: of: increase MAX_RESERVED_REGIONS to 32 2017-10-12 12:23:45 -05:00
firmware firmware: Restore support for built-in firmware 2017-09-16 10:58:48 -07:00
fs Changes since last update: 2017-10-06 15:53:36 -07:00
include SCSI fixes on 20171007 2017-10-07 12:34:16 -07:00
init Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ipc fix a typo in put_compat_shm_info() 2017-09-25 20:41:46 -04:00
kernel Merge branch 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-06 08:36:41 -07:00
lib lib/ratelimit.c: use deferred printk() version 2017-10-03 17:54:26 -07:00
mm mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long 2017-10-03 17:54:26 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-05 08:40:09 -07:00
samples media updates for v4.14-rc1 2017-09-07 12:53:14 -07:00
scripts checkpatch: fix ignoring cover-letter logic 2017-10-03 17:54:26 -07:00
security lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-04 18:03:15 +11:00
sound sound fixes for 4.14-rc4 2017-10-05 10:39:29 -07:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-01 12:06:31 -07:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt Revert "KVM: Don't accept obviously wrong gsi values via KVM_IRQFD" 2017-09-19 08:37:17 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap Update James Hogan's email address 2017-10-04 17:11:53 -07:00
COPYING
CREDITS selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig kbuild: migrate all arch to the kconfig mainmenu upgrade 2010-09-19 22:54:11 -04:00
MAINTAINERS ARC udpates for 4.14-rc4 2017-10-06 15:57:08 -07:00
Makefile Linux 4.14-rc4 2017-10-08 20:53:29 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

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.