From 2b514ec72706a31bea0c3b97e622b81535b5323a Mon Sep 17 00:00:00 2001
From: Roger Pau Monne <roger.pau@citrix.com>
Date: Wed, 24 Mar 2021 13:24:23 +0100
Subject: [PATCH] xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on
MEMORY_HOTPLUG
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The Xen memory hotplug limit should depend on the memory hotplug
generic option, rather than the Xen balloon configuration. It's
possible to have a kernel with generic memory hotplug enabled, but
without Xen balloon enabled, at which point memory hotplug won't work
correctly due to the size limitation of the p2m.
Rename the option to XEN_MEMORY_HOTPLUG_LIMIT since it's no longer
tied to ballooning.
Fixes: 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory")
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210324122424.58685-2-roger.pau@citrix.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
arch/x86/xen/p2m.c | 4 ++--
drivers/xen/Kconfig | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 17d80f751fcb2..a33902d05e45b 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -98,8 +98,8 @@ EXPORT_SYMBOL_GPL(xen_p2m_size);
unsigned long xen_max_p2m_pfn __read_mostly;
EXPORT_SYMBOL_GPL(xen_max_p2m_pfn);
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT
-#define P2M_LIMIT CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT
+#ifdef CONFIG_XEN_MEMORY_HOTPLUG_LIMIT
+#define P2M_LIMIT CONFIG_XEN_MEMORY_HOTPLUG_LIMIT
#else
#define P2M_LIMIT 0
#endif
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index 41645fe6ad48a..ea0efd290c372 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -50,11 +50,11 @@ config XEN_BALLOON_MEMORY_HOTPLUG
SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"
-config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT
+config XEN_MEMORY_HOTPLUG_LIMIT
int "Hotplugged memory limit (in GiB) for a PV guest"
default 512
depends on XEN_HAVE_PVMMU
- depends on XEN_BALLOON_MEMORY_HOTPLUG
+ depends on MEMORY_HOTPLUG
help
Maxmium amount of memory (in GiB) that a PV guest can be
expanded to when using memory hotplug.
--
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