linux-kernel - [PATCH v4 1/3] x86: kallsyms: disable absolute percpu symbols on !SMP

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Message-Id: <1453731572-18448-2-git-send-email-ard.biesheuvel@linaro.org>
Date:	Mon, 25 Jan 2016 15:19:30 +0100
From:	Ard Biesheuvel <ard.biesheuvel@...aro.org>
To:	linux-kernel@...r.kernel.org, linux-s390@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org, x86@...nel.org,
	keescook@...omium.org, akpm@...ux-foundation.org, mingo@...nel.org,
	hpa@...or.com, heiko.carstens@...ibm.com, benh@...nel.crashing.org,
	mpe@...erman.id.au, mmarek@...e.cz, rusty@...tcorp.com.au,
	arnd@...db.de, linux-arch@...r.kernel.org, linux@...ck-us.net
Cc:	Ard Biesheuvel <ard.biesheuvel@...aro.org>
Subject: [PATCH v4 1/3] x86: kallsyms: disable absolute percpu symbols on !SMP

scripts/kallsyms.c has a special --absolute-percpu command line
option which deals with the zero based per cpu offsets that are
used when building for SMP on x86_64. This means that the option
should only be passed in that case, so add a check for CONFIG_SMP.
Otherwise, per cpu variables are recorded as absolute quantities,
(which they are not under !CONFIG_SMP) and they are not relocated
under CONFIG_RELOCATABLE=y.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>
---
 scripts/link-vmlinux.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index ba6c34ea5429..b541c21072f2 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -86,7 +86,7 @@ kallsyms()
 		kallsymopt="${kallsymopt} --page-offset=$CONFIG_PAGE_OFFSET"
 	fi
 
-	if [ -n "${CONFIG_X86_64}" ]; then
+	if [ -n "${CONFIG_X86_64}" ] && [ -n "${CONFIG_SMP}" ]; then
 		kallsymopt="${kallsymopt} --absolute-percpu"
 	fi
 
-- 
2.5.0