According to the SCSI-3 Persistent Reservations specification, when a self-preemption is performed with a key that does not currently hold an active reservation, the operation should be treated as an unregister and should not fail.
The current code in do_mpath_persistent_reserve_out() does not check whether the preempting key has a reservation before invoking the self-preemption path. It unconditionally calls preempt_self() and re-registers the key on the local paths, even when the key has no reservation. This violates the SCSI-3 PR spec and can lead to incorrect reservation states. This patch moves the self-preemption check inside the conditional block so that it only executes when the key matches, but does not bypass the general preemption path for keys without a reservation. With this change, the code will fall through to the common PR_OUT handling (e.g., MPATH_PROUT_RES_SA or CLEAR_SA) when the key is not reserved, allowing the storage target to properly process the operation as an unregister. Signed-off-by: Cykang <[email protected]> --- libmpathpersist/mpath_persist_int.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/libmpathpersist/mpath_persist_int.c b/libmpathpersist/mpath_persist_int.c index 3091c5c2..2ee7fe68 100644 --- a/libmpathpersist/mpath_persist_int.c +++ b/libmpathpersist/mpath_persist_int.c @@ -960,14 +960,15 @@ int do_mpath_persistent_reserve_out(vector curmp, vector pathvec, int fd, ret = preempt_all(mpp, rq_servact, rq_scope, rq_type, noisy); break; + } + /* if we are preempting ourself */ + if (memcmp(paramp->sa_key, paramp->key, 8) == 0) { + ret = preempt_self(mpp, rq_servact, rq_scope, rq_type, + noisy, PREE_WORK_NONE); + break; } } - /* if we are preempting ourself */ - if (memcmp(paramp->sa_key, paramp->key, 8) == 0) { - ret = preempt_self(mpp, rq_servact, rq_scope, rq_type, - noisy, PREE_WORK_NONE); - break; - } + /* fallthrough */ case MPATH_PROUT_RES_SA: case MPATH_PROUT_CLEAR_SA: { -- 2.50.1 (Apple Git-155)
