Commit 9bd3482e ("multipathd: make flush_map() delete maps like the multipath command") fixed a multipathd hang when trying to remove a multipath device with only kpartx devices opening it but with outstanding IO. However that commit didn't deal with autoremoving the multipath device when the last path is deleted. It's possible for the same hang to occur during an autoremove. Since this remove is not initiated by the user, multipathd shouldn't just automatically disable queueing. On the other hand, multipathd hanging is a big problem, since that stops all of its work on all multipath devices. This patchset handles the issue by changing the options for flush_on_last_del to give the users more choice in how to deal with this situation. But none of the options will allow multipath to flush a device while it is queueing, which is the action that can cause it to hang. Differences from v1 (from conversations with Martin Wilck): 0001: Since flush_map_nopaths() will no longer need to know what the deferred_remove setting is, only exported partmap_in_use. 0002: Fixed up the commit message. Removed all of the code treating deferred removes as special in flush_map_nopaths(), and made sure flush_map_nopaths() skipped the autoremove if disabling queueing failed. Original 0003: Dropped. flush_map_nopaths() no longer needs to care about the deferred_remove value, so dm_flush_map_nopaths() does. 0003-0005: New commits based on suggestions from Martin Benjamin Marzinski (5): libmultipath: export partmap_in_use libmultipath: change flush_on_last_del to fix a multipathd hang libmultipath: remove redundant config option from InfiniBox config libmultipath: pad dev_loss_tmo to avoid race with no_path_retry libmultipath: fix deferred_remove function arguments libmultipath/defaults.h | 2 +- libmultipath/devmapper.c | 21 +++++---- libmultipath/devmapper.h | 1 + libmultipath/dict.c | 72 +++++++++++++++++++++++++++---- libmultipath/dict.h | 1 + libmultipath/discovery.c | 5 +++ libmultipath/hwtable.c | 5 +-- libmultipath/libmultipath.version | 3 +- libmultipath/propsel.c | 4 +- libmultipath/structs.h | 7 +-- multipath/multipath.conf.5.in | 20 ++++++--- multipathd/main.c | 39 +++++++++++++---- 12 files changed, 139 insertions(+), 41 deletions(-) -- 2.43.0