On Mon, Apr 8, 2019 at 2:27 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > clang does not support 31 bit object files on s390, so skip > the 32-bit vdso here, and only build it when using gcc to compile > the kernel. What's the build failure? Would you mind filing a bug against LLVM's issue tracker for it, please? > > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> > --- > arch/s390/Kconfig | 3 +++ > arch/s390/kernel/Makefile | 2 +- > arch/s390/kernel/vdso.c | 10 +++++----- > 3 files changed, 9 insertions(+), 6 deletions(-) > > diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig > index b6e3d0653002..8cd860cba4d1 100644 > --- a/arch/s390/Kconfig > +++ b/arch/s390/Kconfig > @@ -388,6 +388,9 @@ config COMPAT > (and some other stuff like libraries and such) is needed for > executing 31 bit applications. It is safe to say "Y". > > +config COMPAT_VDSO > + def_bool COMPAT && !CC_IS_CLANG > + > config SYSVIPC_COMPAT > def_bool y if COMPAT && SYSVIPC > > diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile > index 8a62c7f72e1b..1222db6d4ee9 100644 > --- a/arch/s390/kernel/Makefile > +++ b/arch/s390/kernel/Makefile > @@ -86,7 +86,7 @@ obj-$(CONFIG_TRACEPOINTS) += trace.o > > # vdso > obj-y += vdso64/ > -obj-$(CONFIG_COMPAT) += vdso32/ > +obj-$(CONFIG_COMPAT_VDSO) += vdso32/ > > chkbss := head64.o early_nobss.o > include $(srctree)/arch/s390/scripts/Makefile.chkbss > diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c > index e7920a68a12e..243d8b1185bf 100644 > --- a/arch/s390/kernel/vdso.c > +++ b/arch/s390/kernel/vdso.c > @@ -29,7 +29,7 @@ > #include <asm/vdso.h> > #include <asm/facility.h> > > -#ifdef CONFIG_COMPAT > +#ifdef CONFIG_COMPAT_VDSO > extern char vdso32_start, vdso32_end; > static void *vdso32_kbase = &vdso32_start; > static unsigned int vdso32_pages; > @@ -55,7 +55,7 @@ static vm_fault_t vdso_fault(const struct vm_special_mapping *sm, > > vdso_pagelist = vdso64_pagelist; > vdso_pages = vdso64_pages; > -#ifdef CONFIG_COMPAT > +#ifdef CONFIG_COMPAT_VDSO > if (vma->vm_mm->context.compat_mm) { > vdso_pagelist = vdso32_pagelist; > vdso_pages = vdso32_pages; > @@ -76,7 +76,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm, > unsigned long vdso_pages; > > vdso_pages = vdso64_pages; > -#ifdef CONFIG_COMPAT > +#ifdef CONFIG_COMPAT_VDSO > if (vma->vm_mm->context.compat_mm) > vdso_pages = vdso32_pages; > #endif > @@ -223,7 +223,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) > return 0; > > vdso_pages = vdso64_pages; > -#ifdef CONFIG_COMPAT > +#ifdef CONFIG_COMPAT_VDSO > mm->context.compat_mm = is_compat_task(); > if (mm->context.compat_mm) > vdso_pages = vdso32_pages; > @@ -280,7 +280,7 @@ static int __init vdso_init(void) > int i; > > vdso_init_data(vdso_data); > -#ifdef CONFIG_COMPAT > +#ifdef CONFIG_COMPAT_VDSO > /* Calculate the size of the 32 bit vDSO */ > vdso32_pages = ((&vdso32_end - &vdso32_start > + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1; > -- > 2.20.0 > -- Thanks, ~Nick Desaulniers