Re: [PATCH] fstests Fix build errors on kernels before v5.1

[Lukas Herbolt <lukas@herbolt.com>]

On 2026-07-27 20:07, Zorro Lang wrote:
> On Wed, Jul 22, 2026 at 11:35:44AM +0200, Andrey Albershteyn wrote:
>> On 2026-07-22 07:22:58, Lukas Herbolt wrote:
>> > The FAN_REPORT_FID and fanotify_event_info_fid were introduced
>> > in v5.1. Currently there is no check if the kernel supports it
>> > making xfstests build to fail on older kernels.
>> >
>> > Fixes: 29d120e41c3d ("generic: test fsnotify filesystem error reporting")
>> >
>> > Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
>> 
>> Looks good to me
>> Reviewed-by: Andrey Albershteyn <aalbersh@kernel.org>
>> 
>> > ---
>> >  configure.ac          |  1 +
>> >  include/builddefs.in  |  1 +
>> >  m4/package_libcdev.m4 | 14 ++++++++++++++
>> >  src/Makefile          |  6 +++++-
>> >  4 files changed, 21 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/configure.ac b/configure.ac
>> > index 441f543c6089..feb24ddd8854 100644
>> > --- a/configure.ac
>> > +++ b/configure.ac
>> > @@ -74,6 +74,7 @@ AC_NEED_INTERNAL_XFS_IOC_EXCHANGE_RANGE
>> >  AC_HAVE_FICLONE
>> >  AC_HAVE_TRIVIAL_AUTO_VAR_INIT
>> >  AC_HAVE_FILE_GETATTR
>> > +AC_HAVE_FANOTIFY_FID
>> >
>> >  AC_CHECK_FUNCS([renameat2])
>> >  AC_CHECK_FUNCS([reallocarray])
>> > diff --git a/include/builddefs.in b/include/builddefs.in
>> > index 708d75b24d76..8e9e2e3b4113 100644
>> > --- a/include/builddefs.in
>> > +++ b/include/builddefs.in
>> > @@ -75,6 +75,7 @@ HAVE_RLIMIT_NOFILE = @have_rlimit_nofile@
>> >  NEED_INTERNAL_XFS_IOC_EXCHANGE_RANGE = @need_internal_xfs_ioc_exchange_range@
>> >  HAVE_FICLONE = @have_ficlone@
>> >  HAVE_FILE_GETATTR = @have_file_getattr@
>> > +HAVE_FANOTIFY_FID = @have_fanotify_fid@
>> >
>> >  GCCFLAGS = -std=gnu11 -funsigned-char -fno-strict-aliasing -Wall
>> >  SANITIZER_CFLAGS += @autovar_init_cflags@
>> > diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4
>> > index 17f57f427410..340cdad3faf9 100644
>> > --- a/m4/package_libcdev.m4
>> > +++ b/m4/package_libcdev.m4
>> > @@ -102,3 +102,17 @@ AC_DEFUN([AC_HAVE_FILE_GETATTR],
>> >         AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
>> >      AC_SUBST(have_file_getattr)
>> >    ])
>> > +
>> > +# Check if we have fanotify FID support (Linux 5.1+)
>> > +AC_DEFUN([AC_HAVE_FANOTIFY_FID],
>> > +  [ AC_MSG_CHECKING([for fanotify FID support])
>> > +    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
>> > +#include <sys/fanotify.h>
>> > +    ]], [[
>> > +       int x = FAN_REPORT_FID;
>> > +       struct fanotify_event_info_fid fid;
>> > +       (void)x; (void)fid;
>> > +    ]])],[have_fanotify_fid=yes
>> > +       AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
>> > +    AC_SUBST(have_fanotify_fid)
>> > +  ])
>> > diff --git a/src/Makefile b/src/Makefile
>> > index 31ac43b215e9..847fb168181e 100644
>> > --- a/src/Makefile
>> > +++ b/src/Makefile
>> > @@ -36,7 +36,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
>> >  	fscrypt-crypt-util bulkstat_null_ocount splice-test chprojid_fail \
>> >  	detached_mounts_propagation ext4_resize t_readdir_3 splice2pipe \
>> >  	uuid_ioctl t_snapshot_deleted_subvolume fiemap-fault min_dio_alignment \
>> > -	rw_hint fs-monitor
>> > +	rw_hint
>> >
>> >  EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \
>> >  	      btrfs_crc32c_forged_name.py popdir.pl popattr.py \
>> > @@ -107,6 +107,10 @@ ifeq ($(HAVE_FICLONE),yes)
>> >       TARGETS += t_reflink_read_race
>> >  endif
>> >
>> > +ifeq ($(HAVE_FANOTIFY_FID),yes)
>> > +     TARGETS += fs-monitor
>> ...
>> >       LINUX_TARGETS += t_btrfs_received_uuid_ioctl
>> 
>> hah just noticed that fstests "supports" different targets (darwin,
>> freebsd), not sure if it works at all
> 
> As far as I know, fstests is currently a Linux filesystem testing 
> suite. I don't
> recall us ever being asked to support FreeBSD or other operating 
> systems, though
> I'm not sure if anyone is actually using it that way :)
> 
Then, I would suggest to move everthing under LINUX_TARGETS to keep it 
clean. If there
will be new platform in the future, we can separate it again into 
TARGETS and
${PLATFORM}_TARGETS

-- 
-lhe