Patch "cxl: Fix PSL timebase synchronization detection" has been added to the 4.4-stable tree

Patch "cxl: Fix PSL timebase synchronization detection" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    cxl: Fix PSL timebase synchronization detection

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     cxl-fix-psl-timebase-synchronization-detection.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 923adb1646d5ba739d2a1e63ee20d60574d9da8e Mon Sep 17 00:00:00 2001
From: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Date: Wed, 24 Feb 2016 18:27:51 +0100
Subject: cxl: Fix PSL timebase synchronization detection

From: Frederic Barrat <fbarrat@linux.vnet.ibm.com>

commit 923adb1646d5ba739d2a1e63ee20d60574d9da8e upstream.

The PSL timebase synchronization is seemingly failing for
configuration not including VIRT_CPU_ACCOUNTING_NATIVE. The driver
shows the following trace in dmesg:
PSL: Timebase sync: giving up!

The PSL timebase register is actually syncing correctly, but the cxl
driver is not detecting it. Fix is to use the proper timebase-to-time
conversion.

Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/misc/cxl/pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -414,7 +414,7 @@ static int cxl_setup_psl_timebase(struct
 		delta = mftb() - psl_tb;
 		if (delta < 0)
 			delta = -delta;
-	} while (cputime_to_usecs(delta) > 16);
+	} while (tb_to_ns(delta) > 16000);
 
 	return 0;
 }


Patches currently in stable-queue which might be from fbarrat@linux.vnet.ibm.com are

queue-4.4/cxl-fix-psl-timebase-synchronization-detection.patch