git: lockmgr - Fix bug in lockmgr() cancel path

Matthew Dillon dillon at
Mon Jan 27 15:03:15 PST 2020

commit 0962f67acb7e2f00e1fd3761932999cfe84f2876
Author: Matthew Dillon <dillon at>
Date:   Mon Jan 27 15:00:20 2020 -0800

    lockmgr - Fix bug in lockmgr() cancel path
    * Fix a bug in the lockmgr() cancel path where a cancelable blocked
      exclusive lock is not canceled.  The EXREQ2 bit must be tested in
      addition to EXREQ, as it is possible for EXREQ to be clear when
      EXREQ2 is set.
    * Fixes a situation where the usb path could deadlock a softclock
      cpu thread, causing a cascade of issues on that cpu.

Summary of changes:
 sys/kern/kern_lock.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

DragonFly BSD source repository

More information about the Commits mailing list