1. 30 Mar, 2016 1 commit
    • Paul E. McKenney's avatar
      cpu: Defer smpboot kthread unparking until CPU known to scheduler · 477a64e6
      Paul E. McKenney authored
      commit 00df35f9 upstream.
      
      Currently, smpboot_unpark_threads() is invoked before the incoming CPU
      has been added to the scheduler's runqueue structures.  This might
      potentially cause the unparked kthread to run on the wrong CPU, since the
      correct CPU isn't fully set up yet.
      
      That causes a sporadic, hard to debug boot crash triggering on some
      systems, reported by Borislav Petkov, and bisected down to:
      
        2a442c9c ("x86: Use common outgoing-CPU-notification code")
      
      This patch places smpboot_unpark_threads() in a CPU hotplug
      notifier with priority set so that these kthreads are unparked just after
      the CPU has been added to the runqueues.
      Reported-and-tested-by: default avatarBorislav Petkov <bp@suse.de>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Owen Hofmann <osh@google.com>
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      477a64e6
  2. 29 Mar, 2016 7 commits
  3. 24 Mar, 2016 32 commits