Christophe Leroy <christophe.le...@csgroup.eu> writes: > On 08/26/2020 02:58 PM, Michael Ellerman wrote: >> Christophe Leroy <christophe.le...@csgroup.eu> writes: >>> diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c >>> index daef14a284a3..bbb69832fd46 100644 >>> --- a/arch/powerpc/kernel/vdso.c >>> +++ b/arch/powerpc/kernel/vdso.c >>> @@ -718,16 +710,14 @@ static int __init vdso_init(void) >> ... >>> >>> - >>> -#ifdef CONFIG_VDSO32 >>> vdso32_kbase = &vdso32_start; >>> >>> /* >>> @@ -735,8 +725,6 @@ static int __init vdso_init(void) >>> */ >>> vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT; >>> DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages); >>> -#endif >> >> This didn't build for ppc64le: >> >> >> /opt/cross/gcc-8.20_binutils-2.32/powerpc64-unknown-linux-gnu/bin/powerpc64-unknown-linux-gnu-ld: >> arch/powerpc/kernel/vdso.o:(.toc+0x0): undefined reference to `vdso32_end' >> >> /opt/cross/gcc-8.20_binutils-2.32/powerpc64-unknown-linux-gnu/bin/powerpc64-unknown-linux-gnu-ld: >> arch/powerpc/kernel/vdso.o:(.toc+0x8): undefined reference to `vdso32_start' >> make[1]: *** [/scratch/michael/build/maint/Makefile:1166: vmlinux] Error 1 >> make: *** [Makefile:185: __sub-make] Error 2 >> >> So I just put that ifdef back. >> > > The problem is because is_32bit() can still return true even when > CONFIG_VDSO32 is not set.
Hmm, you're right. My config had CONFIG_COMPAT enabled. But that seems like a bug, if someone enables COMPAT on ppc64le they are almost certainly going to want VDSO32 as well. So I think I'll do a lead up patch as below. cheers diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index d4fd109f177e..cf2da1e401ef 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -501,13 +501,12 @@ endmenu config VDSO32 def_bool y - depends on PPC32 || CPU_BIG_ENDIAN + depends on PPC32 || COMPAT help This symbol controls whether we build the 32-bit VDSO. We obviously want to do that if we're building a 32-bit kernel. If we're building - a 64-bit kernel then we only want a 32-bit VDSO if we're building for - big endian. That is because the only little endian configuration we - support is ppc64le which is 64-bit only. + a 64-bit kernel then we only want a 32-bit VDSO if we're also enabling + COMPAT. choice prompt "Endianness selection"