Patch "cxl: use correct operator when writing pcie config space values" has been added to the 4.4-stable tree

Patch "cxl: use correct operator when writing pcie config space values" 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: use correct operator when writing pcie config space values

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-use-correct-operator-when-writing-pcie-config-space-values.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 48f0f6b717e314a30be121b67e1d044f6d311d66 Mon Sep 17 00:00:00 2001
From: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Date: Wed, 4 Nov 2015 13:24:09 +1100
Subject: cxl: use correct operator when writing pcie config space values

From: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

commit 48f0f6b717e314a30be121b67e1d044f6d311d66 upstream.

When writing a value to config space, cxl_pcie_write_config() calls
cxl_pcie_config_info() to obtain a mask and shift value, shifts the new
value accordingly, then uses the mask to combine the shifted value with the
existing value at the address as part of a read-modify-write pattern.

Currently, we use a logical OR operator rather than a bitwise OR operator,
which means any use of this function results in an incorrect value being
written. Replace the logical OR operator with a bitwise OR operator so the
value is written correctly.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: 6f7f0b3df6d4 ("cxl: Add AFU virtual PHB and kernel API")
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/drivers/misc/cxl/vphb.c
+++ b/drivers/misc/cxl/vphb.c
@@ -203,7 +203,7 @@ static int cxl_pcie_write_config(struct
 	mask <<= shift;
 	val <<= shift;
 
-	v = (in_le32(ioaddr) & ~mask) || (val & mask);
+	v = (in_le32(ioaddr) & ~mask) | (val & mask);
 
 	out_le32(ioaddr, v);
 	return PCIBIOS_SUCCESSFUL;


Patches currently in stable-queue which might be from andrew.donnellan@au1.ibm.com are

queue-4.4/cxl-use-correct-operator-when-writing-pcie-config-space-values.patch