Baoquan He f3cd4c865b mm/memory_hotplug.c: only respect mem= parameter during boot stage ... In commit 357b4da50a ("x86: respect memory size limiting via mem= parameter") a global varialbe max_mem_size is added to store the value parsed from 'mem= ', then checked when memory region is added. This truly stops those DIMMs from being added into system memory during boot-time. However, it also limits the later memory hotplug functionality. Any DIMM can't be hotplugged any more if its region is beyond the max_mem_size. We will get errors like: [ 216.387164] acpi PNP0C80:02: add_memory failed [ 216.389301] acpi PNP0C80:02: acpi_memory_enable_device() error [ 216.392187] acpi PNP0C80:02: Enumeration failure This will cause issue in a known use case where 'mem=' is added to the hypervisor. The memory that lies after 'mem=' boundary will be assigned to KVM guests. After commit 357b4da50a merged, memory can't be extended dynamically if system memory on hypervisor is not sufficient. So fix it by also checking if it's during boot-time restricting to add memory. Otherwise, skip the restriction. And also add this use case to document of 'mem=' kernel parameter. Fixes: 357b4da50a ("x86: respect memory size limiting via mem= parameter") Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: William Kucharski <william.kucharski@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Link: http://lkml.kernel.org/r/20200204050643.20925-1-bhe@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2020-04-07 10:43:40 -07:00
..
ABI	powerpc updates for 5.7	2020-04-05 11:12:59 -07:00
accounting	doc: cgroup: improve formatting of references	2020-03-02 12:57:03 -07:00
admin-guide	mm/memory_hotplug.c: only respect mem= parameter during boot stage	2020-04-07 10:43:40 -07:00
arm	docs: arm: tcm: Fix a few typos	2020-02-19 02:42:21 -07:00
arm64	arm64 updates for 5.7:	2020-03-31 10:05:01 -07:00
block	block: Document genhd capability flags	2020-03-12 07:47:22 -06:00
bpf	bpf: lsm: Add Documentation	2020-03-30 01:35:12 +02:00
cdrom
core-api	mm: add pagemap.h to the fine documentation	2020-04-02 09:35:29 -07:00
cpu-freq	docs: cpu-freq: convert cpufreq-stats.txt to ReST	2020-03-06 00:01:02 +01:00
crypto	crypto: algapi - make unregistration functions return void	2019-12-20 14:58:35 +08:00
dev-tools	linux-kselftest-kunit-5.7-rc1	2020-04-01 16:11:40 -07:00
devicetree	There's not much to see in the core framework this time around. Instead the	2020-04-05 10:43:32 -07:00
doc-guide	Documentation: build warnings related to missing blank lines after explicit markups has been fixed	2020-02-05 10:30:03 -07:00
driver-api	This is the bulk of GPIO development for the v5.7 kernel cycle.	2020-04-04 10:27:00 -07:00
fault-injection
fb	fbdev: fbmem: allow overriding the number of bootup logos	2020-01-03 14:27:40 +01:00
features	documentation: vm: Advertise support for pte_special in riscv	2020-02-19 02:41:01 -07:00
filesystems	1) Replace ext4's bmap and iopoll implementations to use iomap.	2020-04-05 10:54:03 -07:00
firmware_class
firmware-guide	docs: firmware-guide: ACPI: Replace dma_request_slave_channel() with dma_request_chan()	2019-12-19 22:58:12 +01:00
fpga	Documentation: fpga: dfl: add descriptions for thermal/power management interfaces	2019-10-16 19:18:26 -07:00
gpu	UAPI Changes:	2020-03-19 10:40:27 +10:00
hid
hwmon	docs: hwmon: Update documentation for isl68137 pmbus driver	2020-03-22 16:42:54 -07:00
i2c	i2c: convert SMBus alert setup function to return an ERRPTR	2020-03-10 12:19:52 +01:00
ia64
ide
iio
infiniband	Documentation/infiniband: update name of some functions	2019-09-13 16:55:55 -03:00
input
isdn	isdn: capi: dead code removal	2019-12-11 09:12:38 +01:00
kbuild	Kbuild updates for v5.7	2020-03-31 16:03:39 -07:00
kernel-hacking	docs: locking: Drop :c:func: throughout	2020-03-20 17:16:24 -06:00
leds
livepatch	livepatch: Documentation of the new API for tracking system state changes	2019-11-01 13:08:24 +01:00
locking	Documentation/locking/locktypes: Minor copy editor fixes	2020-03-28 12:47:34 +01:00
m68k
maintainer	Add a maintainer entry profile for documentation	2020-01-24 09:48:39 -07:00
media	media updates for v5.7-rc1	2020-03-30 13:42:05 -07:00
mhi	docs: Add documentation for MHI bus	2020-03-19 07:41:04 +01:00
mips	docs: mips: remove no longer needed au1xxx_ide.rst documentation	2020-03-24 15:53:48 +01:00
misc-devices	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2020-04-01 14:47:40 -07:00
netlabel
networking	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next	2020-03-31 17:29:33 -07:00
nios2
nvdimm	docs: nvdimm: use ReST notation for subsection	2020-01-24 09:54:42 -07:00
openrisc
parisc
PCI	pci-v5.7-changes	2020-04-03 14:25:02 -07:00
pcmcia
power	Merge branches 'pm-core', 'pm-sleep', 'pm-acpi' and 'pm-domains'	2020-03-30 14:46:58 +02:00
powerpc	powerpc updates for 5.7	2020-04-05 11:12:59 -07:00
process	Char/Misc driver patches for 5.7-rc1	2020-04-03 13:22:40 -07:00
RCU	doc: Add rcutorture scripting to torture.txt	2020-02-27 07:03:14 -08:00
riscv	It has been a relatively quiet cycle for documentation, but there's still a	2020-01-29 15:27:31 -08:00
s390
scheduler	Documentation/scheduler: fix links in sched-stats	2019-10-29 04:35:41 -06:00
scsi	SCSI misc on 20200402	2020-04-02 17:03:53 -07:00
security	docs: prevent warnings due to autosectionlabel	2020-03-20 17:01:29 -06:00
sh
sound	ALSA: hda/realtek - Remove now-unnecessary XPS 13 headphone noise fixups	2020-03-31 10:54:06 +02:00
sparc
sphinx	docs: Fix empty parallelism argument	2020-02-25 03:11:04 -07:00
sphinx-static	doc-rst: Reduce CSS padding around Field	2019-10-02 10:03:06 -06:00
spi
target	docs: prevent warnings due to autosectionlabel	2020-03-20 17:01:29 -06:00
timers
trace	New tracing features:	2020-04-05 10:36:18 -07:00
translations	media updates for v5.7-rc1	2020-03-30 13:42:05 -07:00
usb	usb: gadget: add raw-gadget interface	2020-03-15 11:34:48 +02:00
userspace-api	docs: userspace: ioctl-number: remove mc146818rtc conflict	2020-02-13 11:42:02 -07:00
virt	ARM:	2020-04-02 15:13:15 -07:00
vm	mm/page_reporting: add free page reporting documentation	2020-04-07 10:43:39 -07:00
w1	docs: w1: Fix a typo in omap-hdq.rst	2019-12-30 11:58:02 -07:00
watchdog	linux-watchdog 5.4-rc1 tag	2019-09-27 11:17:38 -07:00
x86	Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2020-03-31 11:04:05 -07:00
xtensa
.gitignore	.gitignore: add SPDX License Identifier	2020-03-25 11:50:48 +01:00
asm-annotations.rst	Documentation: Call out example SYM_FUNC_* usage as x86-specific	2020-01-16 12:53:16 -07:00
atomic_bitops.txt
atomic_t.txt
bus-virt-phys-mapping.txt
Changes
CodingStyle
conf.py	docs: conf.py: avoid thousands of duplicate label warning on Sphinx	2020-03-20 17:01:34 -06:00
COPYING-logo
crc32.txt
debugging-via-ohci1394.txt
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt	dma-mapping: remove dma_release_declared_memory	2019-09-04 11:13:19 +02:00
DMA-attributes.txt	dma-mapping: remove the DMA_ATTR_WRITE_BARRIER flag	2019-11-14 12:01:54 -04:00
DMA-ISA-LPC.txt
docutils.conf
dontdiff	modpost: dump missing namespaces into a single modules.nsdeps file	2019-11-11 20:10:01 +09:00
futex-requeue-pi.txt
hwspinlock.txt
index.rst	Char/Misc driver patches for 5.7-rc1	2020-04-03 13:22:40 -07:00
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
Kconfig
kprobes.txt
kref.txt	docs: kref: Clarify the use of two kref_put() in example code	2020-02-25 03:39:10 -07:00
logo.gif
lzo.txt
mailbox.txt
Makefile	Kbuild updates for v5.7	2020-03-31 16:03:39 -07:00
memory-barriers.txt	Documentation/memory-barriers: Fix typos	2020-02-27 07:03:14 -08:00
nommu-mmap.txt
percpu-rw-semaphore.txt
pi-futex.txt
preempt-locking.txt
rbtree.txt
remoteproc.txt	remoteproc: Add elf64 support in elf loader	2020-03-25 22:29:40 -07:00
robust-futex-ABI.txt	threads: Update PID limit comment according to futex UAPI change	2020-03-21 17:48:13 +01:00
robust-futexes.txt
rpmsg.txt
speculation.txt
static-keys.txt
SubmittingPatches
tee.txt	Documentation: tee: add AMD-TEE driver details	2020-01-04 13:49:51 +08:00
this_cpu_ops.txt
unaligned-memory-access.txt
xz.txt