On Tue, Jul 27, 2021 at 10:53 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Tue, Jul 27, 2021 at 7:12 AM Pavo Banicevic > <pavo.banicevic@xxxxxxxxxx> wrote: > > > > From: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx> > > > > The samples/bpf with clang -emit-llvm reuses linux headers to build > > bpf samples, and this w/a only for samples (samples/bpf/Makefile > > CLANG-bpf). > > > > It allows to build samples/bpf for arm bpf using clang. > > In another way clang -emit-llvm generates errors like: > > > > CLANG-bpf samples/bpf/tc_l2_redirect_kern.o > > <inline asm>:1:2: error: invalid register/token name > > rev16 r3, r0 > > > > This decision is arguable, probably there is another way, but > > it doesn't have impact on samples/bpf, so it's easier just ignore > > it for clang, at least for now. > > NACK > > The way to fix these is to sort out the header includes, not turning > off arbitrary things that are used by the actual kernel build for 32b > ARM. Would it be too horrible to just get rid of `clang -emit-llvm` and use vmlinux.h (we don't need to do CO-RE, btw, just generate vmlinux.h from the matching kernel)? Kumar has already started moving in that direction in his recent patch set ([0]). Would that get rid of all these issues? [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=519281&state=* > > > > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx> > > --- > > arch/arm/include/asm/swab.h | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/arch/arm/include/asm/swab.h b/arch/arm/include/asm/swab.h > > index c6051823048b..a9fd9cd33d5e 100644 > > --- a/arch/arm/include/asm/swab.h > > +++ b/arch/arm/include/asm/swab.h > > @@ -25,8 +25,11 @@ static inline __attribute_const__ __u32 __arch_swahb32(__u32 x) > > __asm__ ("rev16 %0, %1" : "=r" (x) : "r" (x)); > > return x; > > } > > + > > +#ifndef __clang__ > > #define __arch_swahb32 __arch_swahb32 > > #define __arch_swab16(x) ((__u16)__arch_swahb32(x)) > > +#endif > > > > static inline __attribute_const__ __u32 __arch_swab32(__u32 x) > > { > > -- > > 2.32.0 > > > > > -- > Thanks, > ~Nick Desaulniers
