linux-kernel - [PATCH] powerpc/vdso: Fix build of VDSO32 with pcrel

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <1fa3453f07d42a50a70114da9905bf7b73304fca.1747073669.git.christophe.leroy@csgroup.eu>
Date: Mon, 12 May 2025 20:14:55 +0200
From: Christophe Leroy <christophe.leroy@...roup.eu>
To: Michael Ellerman <mpe@...erman.id.au>,
	Nicholas Piggin <npiggin@...il.com>,
	Naveen N Rao <naveen@...nel.org>,
	Madhavan Srinivasan <maddy@...ux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@...roup.eu>,
	linux-kernel@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH] powerpc/vdso: Fix build of VDSO32 with pcrel

Building vdso32 on power10 with pcrel leads to following errors:

	  VDSO32A arch/powerpc/kernel/vdso/gettimeofday-32.o
	arch/powerpc/kernel/vdso/gettimeofday.S: Assembler messages:
	arch/powerpc/kernel/vdso/gettimeofday.S:40: Error: syntax error; found `@', expected `,'
	arch/powerpc/kernel/vdso/gettimeofday.S:71:  Info: macro invoked from here
	arch/powerpc/kernel/vdso/gettimeofday.S:40: Error: junk at end of line: `@...oc'
	arch/powerpc/kernel/vdso/gettimeofday.S:71:  Info: macro invoked from here
	 ...
	make[2]: *** [arch/powerpc/kernel/vdso/Makefile:85: arch/powerpc/kernel/vdso/gettimeofday-32.o] Error 1
	make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2

Once the above is fixed, the following happens:

	  VDSO32C arch/powerpc/kernel/vdso/vgettimeofday-32.o
	cc1: error: '-mpcrel' requires '-mcmodel=medium'
	make[2]: *** [arch/powerpc/kernel/vdso/Makefile:89: arch/powerpc/kernel/vdso/vgettimeofday-32.o] Error 1
	make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2
	make: *** [Makefile:251: __sub-make] Error 2

Make sure pcrel version of CFUNC() macro is used only for powerpc64
builds and remove -mpcrel for powerpc32 builds.

Fixes: 7e3a68be42e1 ("powerpc/64: vmlinux support building with PCREL addresing")
Signed-off-by: Christophe Leroy <christophe.leroy@...roup.eu>
---
 arch/powerpc/include/asm/ppc_asm.h | 2 +-
 arch/powerpc/kernel/vdso/Makefile  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 02897f4b0dbf..b891910fce8a 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -183,7 +183,7 @@
 /*
  * Used to name C functions called from asm
  */
-#ifdef CONFIG_PPC_KERNEL_PCREL
+#if defined(__powerpc64__) && defined(CONFIG_PPC_KERNEL_PCREL)
 #define CFUNC(name) name@...oc
 #else
 #define CFUNC(name) name
diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile
index e8824f933326..8834dfe9d727 100644
--- a/arch/powerpc/kernel/vdso/Makefile
+++ b/arch/powerpc/kernel/vdso/Makefile
@@ -53,7 +53,7 @@ ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WAR
 ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
 
 CC32FLAGS := -m32
-CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc
+CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc -mpcrel
 ifdef CONFIG_CC_IS_CLANG
 # This flag is supported by clang for 64-bit but not 32-bit so it will cause
 # an unused command line flag warning for this file.
-- 
2.47.0