Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc merge from Benjamin Herrenschmidt:
 "Here's the powerpc batch for this merge window.  It is going to be a
  bit more nasty than usual as in touching things outside of
  arch/powerpc mostly due to the big iSeriesectomy :-) We finally got
  rid of the bugger (legacy iSeries support) which was a PITA to
  maintain and that nobody really used anymore.

  Here are some of the highlights:

   - Legacy iSeries is gone.  Thanks Stephen ! There's still some bits
     and pieces remaining if you do a grep -ir series arch/powerpc but
     they are harmless and will be removed in the next few weeks
     hopefully.

   - The 'fadump' functionality (Firmware Assisted Dump) replaces the
     previous (equivalent) "pHyp assisted dump"...  it's a rewrite of a
     mechanism to get the hypervisor to do crash dumps on pSeries, the
     new implementation hopefully being much more reliable.  Thanks
     Mahesh Salgaonkar.

   - The "EEH" code (pSeries PCI error handling & recovery) got a big
     spring cleaning, motivated by the need to be able to implement a
     new backend for it on top of some new different type of firwmare.

     The work isn't complete yet, but a good chunk of the cleanups is
     there.  Note that this adds a field to struct device_node which is
     not very nice and which Grant objects to.  I will have a patch soon
     that moves that to a powerpc private data structure (hopefully
     before rc1) and we'll improve things further later on (hopefully
     getting rid of the need for that pointer completely).  Thanks Gavin
     Shan.

   - I dug into our exception & interrupt handling code to improve the
     way we do lazy interrupt handling (and make it work properly with
     "edge" triggered interrupt sources), and while at it found & fixed
     a wagon of issues in those areas, including adding support for page
     fault retry & fatal signals on page faults.

   - Your usual random batch of small fixes & updates, including a bunch
     of new embedded boards, both Freescale and APM based ones, etc..."

I fixed up some conflicts with the generalized irq-domain changes from
Grant Likely, hopefully correctly.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (141 commits)
  powerpc/ps3: Do not adjust the wrapper load address
  powerpc: Remove the rest of the legacy iSeries include files
  powerpc: Remove the remaining CONFIG_PPC_ISERIES pieces
  init: Remove CONFIG_PPC_ISERIES
  powerpc: Remove FW_FEATURE ISERIES from arch code
  tty/hvc_vio: FW_FEATURE_ISERIES is no longer selectable
  powerpc/spufs: Fix double unlocks
  powerpc/5200: convert mpc5200 to use of_platform_populate()
  powerpc/mpc5200: add options to mpc5200_defconfig
  powerpc/mpc52xx: add a4m072 board support
  powerpc/mpc5200: update mpc5200_defconfig to fit for charon board
  Documentation/powerpc/mpc52xx.txt: Checkpatch cleanup
  powerpc/44x: Add additional device support for APM821xx SoC and Bluestone board
  powerpc/44x: Add support PCI-E for APM821xx SoC and Bluestone board
  MAINTAINERS: Update PowerPC 4xx tree
  powerpc/44x: The bug fixed support for APM821xx SoC and Bluestone board
  powerpc: document the FSL MPIC message register binding
  powerpc: add support for MPIC message register API
  powerpc/fsl: Added aliased MSIIR register address to MSI node in dts
  powerpc/85xx: mpc8548cds - add 36-bit dts
  ...

1 files changed, 21 insertions, 2 deletions

diff --git a/arch/powerpc/mm/icswx.c b/arch/powerpc/mm/icswx.c
index 5d9a59eaad9..8cdbd8634a5 100644
--- a/arch/powerpc/mm/icswx.c
+++ b/arch/powerpc/mm/icswx.c
@@ -163,7 +163,7 @@ EXPORT_SYMBOL_GPL(drop_cop);
 
 static int acop_use_cop(int ct)
 {
-	/* todo */
+	/* There is no alternate policy, yet */
 	return -1;
 }
 
@@ -227,11 +227,30 @@ int acop_handle_fault(struct pt_regs *regs, unsigned long address,
 		ct = (ccw >> 16) & 0x3f;
 	}
 
+	/*
+	 * We could be here because another thread has enabled acop
+	 * but the ACOP register has yet to be updated.
+	 *
+	 * This should have been taken care of by the IPI to sync all
+	 * the threads (see smp_call_function(sync_cop, mm, 1)), but
+	 * that could take forever if there are a significant amount
+	 * of threads.
+	 *
+	 * Given the number of threads on some of these systems,
+	 * perhaps this is the best way to sync ACOP rather than whack
+	 * every thread with an IPI.
+	 */
+	if ((acop_copro_type_bit(ct) & current->active_mm->context.acop) != 0) {
+		sync_cop(current->active_mm);
+		return 0;
+	}
+
+	/* check for alternate policy */
 	if (!acop_use_cop(ct))
 		return 0;
 
 	/* at this point the CT is unknown to the system */
-	pr_warn("%s[%d]: Coprocessor %d is unavailable",
+	pr_warn("%s[%d]: Coprocessor %d is unavailable\n",
 		current->comm, current->pid, ct);
 
 	/* get inst if we don't already have it */