<tt>Hello, Mike</tt> Thanks for your quick respond. This problem causes failure in "rmmod dm-spp" command, (dm-spp is a tagert type for our product) since the <tt>reference count</tt> is not zero due to the failure of <tt>DM table loads</tt>. I don't intend to cc <tt>stable</tt>, I just add the "Cc: stable@vger.kernel.org" after <tt>Signed-off-by</tt> in commit message as Bart suggested it to me, then I send email by "git send-email" command, and it cc to <tt>stable</tt> automatically, I think maybe my git is not configured well, I'll research it later. <tt>(BTW, I like your name, Mike, Thank you for your </tt>accompanying<tt> </tt> <tt>with us in our English class for so many years.)</tt> thanks, Tang 发件人: Mike Snitzer <snitzer@redhat.com> 收件人: tang.junhui@zte.com.cn, 抄送: zhang.kai16@zte.com.cn, dm-devel@redhat.com, stable@vger.kernel.org, agk@redhat.com 日期: 2016/10/21 10:24 主题: Re: [dm-devel] md/dm-table: tgt->type should be putted in dm_table_add_target() 发件人: dm-devel-bounces@redhat.com <hr noshade> <tt>On Thu, Oct 20 2016 at 9:35pm -0400, tang.junhui@zte.com.cn <tang.junhui@zte.com.cn> wrote: > From: "tang.junhui" <tang.junhui@zte.com.cn> > > tgt->type should be putted in dm_table_add_target() > when the target do not statisfy the needs of target type, > otherwise it would cause the module reference count > of this target type leakage. > > Signed-off-by: tang.junhui <tang.junhui@zte.com.cn> > Cc: stable@vger.kernel.org This issue, missing dm_put_target_type, dates back to 2011. See these 3 commits: $ git log --oneline 3791e2fc0^..36a0456fb 36a0456 dm table: add immutable feature cc6cbe1 dm table: add always writeable feature 3791e2f dm table: add singleton feature So are you having problems with failed DM table loads (due to the errors below) resulting in the inability to unload a DM module? (BTW, you don't need to cc stable when initially proposing a patch for stable. The stable@ maintainers will automatically pull such stable@ changes in once they land in Linus' tree.) Mike > --- > drivers/md/dm-table.c | 24 ++++++++++++------------ > 1 file changed, 12 insertions(+), 12 deletions(-) > > diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c > index 6554d91..4f56c38 100644 > --- a/drivers/md/dm-table.c > +++ b/drivers/md/dm-table.c > @@ -698,30 +698,30 @@ int dm_table_add_target(struct dm_table *t, const char *type, > > if (dm_target_needs_singleton(tgt->type)) { > if (t->num_targets) { > - DMERR("%s: target type %s must appear alone in table", > - dm_device_name(t->md), type); > - return -EINVAL; > + tgt->error = "target type must appear alone in table"; > + r = -EINVAL; > + goto bad; > } > t->singleton = 1; > } > > if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) { > - DMERR("%s: target type %s may not be included in read-only tables", > - dm_device_name(t->md), type); > - return -EINVAL; > + tgt->error = "target type may not be included in read-only tables"; > + r = -EINVAL; > + goto bad; > } > > if (t->immutable_target_type) { > if (t->immutable_target_type != tgt->type) { > - DMERR("%s: immutable target type %s cannot be mixed with other target types", > - dm_device_name(t->md), t->immutable_target_type->name); > - return -EINVAL; > + tgt->error = "immutable target type cannot be mixed with other target types"; > + r = -EINVAL; > + goto bad; > } > } else if (dm_target_is_immutable(tgt->type)) { > if (t->num_targets) { > - DMERR("%s: immutable target type %s cannot be mixed with other target types", > - dm_device_name(t->md), tgt->type->name); > - return -EINVAL; > + tgt->error = "immutable target type cannot be mixed with other target types"; > + r = -EINVAL; > + goto bad; > } > t->immutable_target_type = tgt->type; > } > -- > 2.8.1.windows.1 > -- dm-devel mailing list dm-devel@redhat.com </tt><a href="https://www.redhat.com/mailman/listinfo/dm-devel"><tt>https://www.redhat.com/mailman/listinfo/dm-devel</tt></a><tt> </tt>