On Wed, Nov 13, 2019 at 2:52 PM Xiao Yang <ice_yangxiao@xxxxxxx> wrote: > > On 11/13/19 1:28 PM, Masahiro Yamada wrote: > > On Wed, Nov 13, 2019 at 12:13 AM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote: > >> On 11/12/19 1:50 PM, Masahiro Yamada wrote: > >>> On Tue, Nov 12, 2019 at 9:31 PM Will Deacon <will@xxxxxxxxxx> wrote: > >>>> [+lkml, Masahiro, Alexei and Daniel] > >>>> > >>>> On Tue, Nov 12, 2019 at 04:56:39PM +0800, Xiao Yang wrote: > >>>>> With your patch[1], I alway get the following error when building > >>>>> tools/bpf: > >>>> In case people want to reproduce this, my branch is here: > >>>> > >>>> https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/log/?h=lto > >>>> > >>>>> ---------------------------------------------------------------------------------- > >>>>> > >>>>> make -C tools/bpf/ > >>>>> make: Entering directory > >>>>> '/usr/src/perf_selftests-x86_64-rhel-7.6-642a312d47ceb54603630d9d04f5052f3b46d9a3/tools/bpf' > >>>>> > >>>>> Auto-detecting system features: > >>>>> ... libbfd: [ on ] > >>>>> ... disassembler-four-args: [ OFF ] > >>>>> > >>>>> CC bpf_jit_disasm.o > >>>>> CC bpf_dbg.o > >>>>> In file included from > >>>>> /usr/src/perf_selftests-x86_64-rhel-7.6-642a312d47ceb54603630d9d04f5052f3b46d9a3/include/uapi/linux/filter.h:9:0, > >>>>> from > >>>>> /usr/src/perf_selftests-x86_64-rhel-7.6-642a312d47ceb54603630d9d04f5052f3b46d9a3/tools/bpf/bpf_dbg.c:41: > >>>>> /usr/src/perf_selftests-x86_64-rhel-7.6-642a312d47ceb54603630d9d04f5052f3b46d9a3/include/linux/compiler.h:247:24: > >>>>> fatal error: asm/rwonce.h: No such file or directory > >>>>> #include <asm/rwonce.h> > >>>>> ^ > >>>>> compilation terminated. > >>>>> Makefile:61: recipe for target 'bpf_dbg.o' failed > >>>>> make: *** [bpf_dbg.o] Error 1 > >>>>> make: *** Waiting for unfinished jobs.... > >>>>> make: Leaving directory > >>>>> > >>>>> ---------------------------------------------------------------------------------- > >>>>> > >>>>> [1] https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/commit/?h=lto&id=642a312d47ceb54603630d9d04f5052f3b46d9a3 > >>>>> > >>>>> It seems that include/linux/compiler.h cannot find the asm/rwonce.h because > >>>>> tools/bpf/Makefile doesn't include arch/*/include/generated/asm/rwonce.h. > >>>> The problem with referring to the generated files is that they don't exist > >>>> unless you've configured the main source directory. The real problem here > >>>> seems to be that tools/bpf/ refers directly to header files in the kernel > >>>> sources without any understanding of kbuild, and therefore mandatory-y > >>>> headers simply don't exist when it goes looking for them. > >> Hmm, I am puzzled why that is. :/ I think there are two options, i) remove it > >> from CFLAGS like below (at least this doesn't let the build fail in my case > >> but requires linux headers to be installed) or ii) add a copy of filter.h to > >> tools/include/uapi/linux/filter.h so the few tools can just reuse it. We do have > >> bpf_common.h and bpf.h there already. > >> > >> diff --git a/tools/bpf/Makefile b/tools/bpf/Makefile > >> index 5d1995fd369c..08dfd289174c 100644 > >> --- a/tools/bpf/Makefile > >> +++ b/tools/bpf/Makefile > >> @@ -10,7 +10,6 @@ MAKE = make > >> INSTALL ?= install > >> > >> CFLAGS += -Wall -O2 > >> -CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/include/uapi -I$(srctree)/include > >> > >> # This will work when bpf is built in tools env. where srctree > >> # isn't set and when invoked from selftests build, where srctree > >> > > > > I think this is the most sane fix > > to include the linux/filter.h in the system. > > > > (probably, it is located in /usr/include/linux/filter.h) > > Hi Masahiro, > > Is it correct for include/linux/compiler.h to include <asm/rwonce.h>? Sorry, I really do not understand what you are doing. include/linux/compiler.h is only for kernel-space. Shrug if a user-land program includes it. > On x86_64 arch, asm/rwonce.h is generated in > ./arch/x86/include/generated/ directory and compiler.h cannot find it. > > Best Regards, > > XIao Yang > > > > > > -- Best Regards Masahiro Yamada
