As announced previously, here comes a collection of multipath-tools patches that SUSE is using for SLES12 SP2. The whole series can be roughly broken down into the following logical parts. Details can be found in the indvidual patches. A) Modified boot sequence (01, 02, 04): Under SLES12, the systemd service startup sequence has been changed such that multipathd is now started after "udev settle" has finished. This has solved a variety of sporadic, hard-to-track boot-time problems for us. The bottom line is that until "udev settle" finishes, the udev db is incomplete when multipathd tries to derive device information from it. That may cause multipathd to infer incorrectly that a certain map is degraded, causing all kinds of problems. B) Changed command line option semantices with find_multipaths (16, 17): SUSE uses "multipath -i" in udev rules during device detection, as discussed by Hannes on this list previously. This doesn't work well with the "find_multipaths" option. We worked around this by relying on WWID for the "find_multipaths" case, as other distributions do. C) Avoid unnecessary domap() calls in configure() (18-28): This patch series fixes another group of boot-time problems we encountered in reboot tests. In many cases, multipathd has already set up valid maps during initrd processing. When multipathd is restarted after switching to the root FS, more often than not, no configuration changes are necessary. Yet domap() is called for every map again. This call may race with other boot-time operations such as LVM pvscan or mount commands and cause sporadic boot failures. The idea of this series of patches is to detect this situation and avoid calling making device mapper calls if the multipath internal representation of the map already matches the kernel state. The logic of this series works only if the udev db is in a sane state after switching root, thus it's closely related to A). Side note: This modified logic was also the background of my earlier remarks about the possible processing of uevent batches using configure(). Based on this series, further changes for configure could be written that would make this possible. D) Misc bug fixes (all except those mentioned so far). For those who prefer github, the whole series is also available on https://github.com/mwilck/multipath-tools/commits/upstream_170228 Best Regards, Martin Hannes Reinecke (15): multipathd.service: fixup Wants= and Before= statements multipathd: start daemon after udev trigger multipath: do not check daemon from udev rules Invalid error code when using multipathd CLI multipathd: set timeout for CLI commands correctly libmultipath: fall back to search paths by devt libmultipath: Do not crash on empty features multipathd: Set CLI timeout correctly multipath: avoid crash when using modified configuration multipathd: issue systemd READY after initial configuration libmultipath/discovery: do not cache 'access_state' sysfs attribute libmultipath: use existing alias from bindings file kpartx: sanitize delete partitions tur: Add pthread_testcancel() multipathd: fixup check for new path states Martin Wilck (18): Add support for "multipath=off" and "nompath" on kernel cmdline multipath -ll: set DI_SERIAL libmultipath: move suspend logic to _dm_flush_map multipath: ignore -i if find_multipaths is set multipathd: imply -n if find_multipaths is set multipathd: use weaker "force_reload" at startup libmultipath: setup_features: log msg if queue_if_no_path is ignored libmultipath: setup_feature: print log msg if no_path_retry cant be set libmultipath: setup_feature: handle "retain_attached_hw_handler" libmultipath: disassemble_map: skip no_path_retry check libmultipath: disassemble_map: treat minio like assemble_map does libmultipath: select_action: check special features separately libmultipath: sysfs_attr_set_value: use const char* libmultipath: reload map if not known to udev libmultipath: differentiate ACT_NOTHING and ACT_IMPOSSIBLE libmultipath: coalesce_paths: trigger uevent if nothing done libmultipath/checkers: make RADOS checker optional Make libdmmp build optional Makefile | 6 +- Makefile.inc | 6 ++ kpartx/devmapper.c | 229 +++++++++++++++++++++++++++++++++++++++-- kpartx/devmapper.h | 7 +- kpartx/kpartx.c | 44 ++------ libmpathcmd/mpath_cmd.c | 4 + libmpathcmd/mpath_cmd.h | 2 +- libmultipath/alias.c | 8 ++ libmultipath/checkers/Makefile | 6 +- libmultipath/checkers/tur.c | 1 + libmultipath/config.h | 6 ++ libmultipath/configure.c | 117 +++++++++++++++++++-- libmultipath/configure.h | 1 + libmultipath/devmapper.c | 102 ++++++++---------- libmultipath/devmapper.h | 9 +- libmultipath/discovery.c | 19 ++-- libmultipath/dmparser.c | 26 +++-- libmultipath/print.c | 2 +- libmultipath/propsel.c | 4 +- libmultipath/structs.c | 39 ++++--- libmultipath/sysfs.c | 2 +- libmultipath/sysfs.h | 2 +- libmultipath/util.c | 59 +++++++++++ libmultipath/util.h | 1 + libmultipath/uxsock.c | 9 +- multipath/main.c | 37 ++++--- multipath/multipath.rules | 5 + multipathd/cli_handlers.c | 3 +- multipathd/main.c | 31 ++++-- multipathd/multipathd.service | 10 +- 30 files changed, 603 insertions(+), 194 deletions(-) -- 2.11.0 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
