On Mon, May 18 2026, Vipin Sharma wrote: > On Mon, May 18, 2026 at 11:29:49AM +0000, [email protected] wrote: >> Vipin Sharma <[email protected]> writes: >> >> > Add helper functions to preserve and retrieve file descriptors from an >> > LUO session. This allows library users to work with FD preservation. >> > >> > No functional change intended. >> > >> > Signed-off-by: Vipin Sharma <[email protected]> >> > Co-developed-by: David Matlack <[email protected]> >> > Signed-off-by: David Matlack <[email protected]> >> > Signed-off-by: Vipin Sharma <[email protected]> >> > --- >> > .../liveupdate/lib/include/libliveupdate.h | 3 ++ >> > .../selftests/liveupdate/lib/liveupdate.c | 41 +++++++++++++++---- >> > 2 files changed, 35 insertions(+), 9 deletions(-) >> > >> > diff --git >> > a/tools/testing/selftests/liveupdate/lib/include/libliveupdate.h >> > b/tools/testing/selftests/liveupdate/lib/include/libliveupdate.h >> > index 4390a2737930..2b04b3256382 100644 >> > --- a/tools/testing/selftests/liveupdate/lib/include/libliveupdate.h >> > +++ b/tools/testing/selftests/liveupdate/lib/include/libliveupdate.h >> > @@ -26,6 +26,9 @@ int luo_create_session(int luo_fd, const char *name); >> > int luo_retrieve_session(int luo_fd, const char *name); >> > int luo_session_finish(int session_fd); >> > >> > +int luo_session_preserve_fd(int session_fd, int fd, __u64 token); >> > +int luo_session_retrieve_fd(int session_fd, __u64 token); >> > + >> > int create_and_preserve_memfd(int session_fd, int token, const char >> > *data); >> > int restore_and_verify_memfd(int session_fd, int token, const char >> > *expected_data); >> > >> > diff --git a/tools/testing/selftests/liveupdate/lib/liveupdate.c >> > b/tools/testing/selftests/liveupdate/lib/liveupdate.c >> > index 60121873f685..7bc6707d8bb7 100644 >> > --- a/tools/testing/selftests/liveupdate/lib/liveupdate.c >> > +++ b/tools/testing/selftests/liveupdate/lib/liveupdate.c >> > @@ -54,9 +54,35 @@ int luo_retrieve_session(int luo_fd, const char *name) >> > return arg.fd; >> > } >> > >> > +int luo_session_preserve_fd(int session_fd, int fd, __u64 token) >> > +{ >> > + struct liveupdate_session_preserve_fd arg = { >> > + .size = sizeof(arg), >> > + .fd = fd, >> > + .token = token, >> > + }; >> > + >> > + if (ioctl(session_fd, LIVEUPDATE_SESSION_PRESERVE_FD, &arg) < 0) >> > + return -errno; >> > + >> > + return 0; >> > +} >> > + >> > +int luo_session_retrieve_fd(int session_fd, __u64 token) >> nit: Can add a comment that, once it is failed, retrieved status is saved, >> So it is permanent failure. > > I think appropriate place will be the official documentation which is > here include/uapi/linux/liveupdate.h > > I don't see it is mentioned in the documentation (yes, code does what > you have said), I will refrain from adding that comment here.
Would be a good addition to the LUO docs I think. Patches welcome :-) [...] -- Regards, Pratyush Yadav
