Re: [PATCH 4/4] scripts/nsdeps: make sure to pass all module source files to spatch

Jessica Yu
2019-10-31T13:41:23Z

+++ Masahiro Yamada [31/10/19 21:27 +0900]:
>On Thu, Oct 31, 2019 at 1:17 AM Jessica Yu <jeyu@kernel.org> wrote:
>>
>> +++ Masahiro Yamada [29/10/19 21:57 +0900]:
>> >On Tue, Oct 29, 2019 at 12:14 AM Jessica Yu <jeyu@kernel.org> wrote:
>> >>
>> >> The nsdeps script passes a list of the module source files to
>> >> generate_deps_for_ns() as a space delimited string named $mod_source_files,
>> >> which then passes it to spatch. But since $mod_source_files is not encased
>> >> in quotes, each source file in that string is treated as a separate shell
>> >> function argument (as $2, $3, $4, etc.). However, the spatch invocation
>> >> only refers to $2, so only the first file out of $mod_source_files is
>> >> processed by spatch.
>> >>
>> >> This causes problems (namely, the MODULE_IMPORT_NS() statement doesn't
>> >> get inserted) when a module is composed of many source files and the
>> >> "main" module file containing the MODULE_LICENSE() statement is not the
>> >> first file listed in $mod_source_files. Fix this by encasing
>> >> $mod_source_files in quotes so that the entirety of the string is
>> >> treated as a single argument and can be referred to as $2.
>> >>
>> >> Signed-off-by: Jessica Yu <jeyu@kernel.org>
>> >> ---
>> >> scripts/nsdeps | 2 +-
>> >> 1 file changed, 1 insertion(+), 1 deletion(-)
>> >>
>> >> diff --git a/scripts/nsdeps b/scripts/nsdeps
>> >> index 9ddcd5cb96b1..5055b059a81b 100644
>> >> --- a/scripts/nsdeps
>> >> +++ b/scripts/nsdeps
>> >> @@ -36,7 +36,7 @@ generate_deps() {
>> >> | sed -E "s%(^|\s)([^/][^ ]*)%\1$srctree/\2%g"`
>> >> for ns in `cat $ns_deps_file`; do
>> >> echo "Adding namespace $ns to module $mod_name (if needed)."
>> >> - generate_deps_for_ns $ns $mod_source_files
>> >> + generate_deps_for_ns $ns "$mod_source_files"
>> >> # sort the imports
>> >> for source_file in $mod_source_files; do
>> >> sed '/MODULE_IMPORT_NS/Q' $source_file > ${source_file}.tmp
>> >
>> >I think this change is correct, but
>> >did you succeed in nsdeps for composite modules
>> >with this patch only?
>> >
>> >I think the following is needed too:
>> >
>> >
>> >diff --git a/scripts/nsdeps b/scripts/nsdeps
>> >index dda6fbac016e..5a23ea616446 100644
>> >--- a/scripts/nsdeps
>> >+++ b/scripts/nsdeps
>> >@@ -31,9 +31,9 @@ generate_deps() {
>> > local mod_file=`echo $@ | sed -e 's/\.ko/\.mod/'`
>> > local ns_deps_file=`echo $@ | sed -e 's/\.ko/\.ns_deps/'`
>> > if [ ! -f "$ns_deps_file" ]; then return; fi
>> >- local mod_source_files=`cat $mod_file | sed -n 1p \
>> >+ local mod_source_files="`cat $mod_file | sed -n 1p
>> > \
>> > | sed -e 's/\.o/\.c/g' \
>> >- | sed "s|[^ ]* *|${srctree}/&|g"`
>> >+ | sed "s|[^ ]* *|${srctree}/&|g"`"
>> > for ns in `cat $ns_deps_file`; do
>> > echo "Adding namespace $ns to module $mod_name (if needed)."
>> > generate_deps_for_ns $ns $mod_source_files
>> >
>> >
>> >Without this, a module that consists of two files
>> >will be expanded to:
>> >
>> >local mod_source_files=source1.c source2.c
>>
>> Yes, I was able to have nsdeps work for composite modules with just my
>> patch. Without this patch applied, the script produces the following
>> expansion of the generate_deps_for_ns call, (I just added a test
>> namespace MODULE):
>>
>> Adding namespace MODULE to module fs/nfs/nfs.ko.
>> + generate_deps_for_ns MODULE /tmp/ppyu/linux/fs/nfs/client.c /tmp/ppyu/linux/fs/nfs/dir.c /tmp/ppyu/linux/fs/nfs/file.c /tmp/ppyu/linux/fs/nfs/getroot.c /tmp/ppyu/linux/fs/nfs/inode.c /tmp/ppyu/linux/fs/nfs/super.c /tmp/ppyu/linux/fs/nfs/io.c /tmp/ppyu/linux/fs/nfs/direct.c /tmp/ppyu/linux/fs/nfs/pagelist.c /tmp/ppyu/linux/fs/nfs/read.c /tmp/ppyu/linux/fs/nfs/symlink.c /tmp/ppyu/linux/fs/nfs/unlink.c /tmp/ppyu/linux/fs/nfs/write.c /tmp/ppyu/linux/fs/nfs/namespace.c /tmp/ppyu/linux/fs/nfs/mount_clnt.c /tmp/ppyu/linux/fs/nfs/nfstrace.c /tmp/ppyu/linux/fs/nfs/export.c /tmp/ppyu/linux/fs/nfs/sysfs.c /tmp/ppyu/linux/fs/nfs/sysctl.c /tmp/ppyu/linux/fs/nfs/fscache.c /tmp/ppyu/linux/fs/nfs/fscache-index.c
>> + /usr/bin/spatch --very-quiet --in-place --sp-file /tmp/ppyu/linux/scripts/coccinelle/misc/add_namespace.cocci -D ns=MODULE /tmp/ppyu/linux/fs/nfs/client.c
>>
>> So only the first file got included in the spatch invocation. But the
>> spatch call gets fixed with all the files when quotes are added in the
>> call to generate_deps_for_ns.
>>
>> But we need to include your change anyway, to make the script more
>> robust.
>
>Hmm.
>With this patch only, I see "bad variable name" error.
>
>
>
>masahiro@grover:~/ref/linux$ make -j8 nsdeps
> DESCEND objtool
> CALL scripts/atomic/check-atomics.sh
> CALL scripts/checksyscalls.sh
> CHK include/generated/compile.h
> Building modules, stage 2.
> MODPOST 20 modules
>WARNING: module nfs uses symbol foo from namespace USB_STORAGE, but
>does not import it.
> Building modules, stage 2.
> MODPOST 20 modules
>./scripts/nsdeps: 34: local: ./fs/nfs/dir.c: bad variable name
>make: *** [Makefile;1689: nsdeps] Error 2

Hm, I was having trouble reproducing this until I changed the shell to
dash, /bin/sh is a symlink to bash on my system, that might explain
slightly different behavior. In any case, we should add quotes in both
places.

>> It would probably prevent more shell script related bugs in
>> the future (Like [1]). I can respin this patch only while the other
>> ones are superceded by your patchset.
>>
>> [1] https://unix.stackexchange.com/a/131767
>
>Anyway.
>
>Is this patch aiming for v5.4 (i.e. fixes) or v5.5-rc1 ?

I am hoping for fixes, we should try to get all the small bugs out of
nsdeps by 5.4 if we can..

>If you touch the mod_source_files line,
>we will have a conflict because
>https://patchwork.kernel.org/patch/11217839/
>is touching the same line.
>
>How should we organize the patch order?

Would you like to fold these changes into your nsdeps improvements
patchset? Since it's a pretty trivial change.

Thanks!