[PATCH] x86/boot/KASLR: Fix unused variable warning

From: Zhenzhong Duan
Date: Fri Jan 10 2020 - 04:43:23 EST


Local variable 'i' is referenced only when CONFIG_MEMORY_HOTREMOVE and
CONFIG_ACPI are defined, but definition of variable 'i' is out of guard.
If any of the two macros is undefined, below warning triggers during
build with 'make EXTRA_CFLAGS=-Wall binrpm-pkg', fix it by moving 'i'
in the guard.

arch/x86/boot/compressed/kaslr.c:698:6: warning: unused variable âiâ [-Wunused-variable]

Fixes: 690eaa532057 ("x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx>
---
v3: remove changes from 0/1 to false/true per Tglx
add the command details about triggering build warning per Boris

v2: update description per Boris.

arch/x86/boot/compressed/kaslr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index d7408af55738..62bc46684581 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -695,7 +695,6 @@ static bool process_mem_region(struct mem_vector *region,
unsigned long long minimum,
unsigned long long image_size)
{
- int i;
/*
* If no immovable memory found, or MEMORY_HOTREMOVE disabled,
* use @region directly.
@@ -711,6 +710,7 @@ static bool process_mem_region(struct mem_vector *region,
}

#if defined(CONFIG_MEMORY_HOTREMOVE) && defined(CONFIG_ACPI)
+ int i;
/*
* If immovable memory found, filter the intersection between
* immovable memory and @region.
--
2.17.1