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[3.13.y.z,extended,stable] Patch "s390/lowcore: reserve 96 bytes for IRB in lowcore" has been added to staging queue

Message ID 1405459764-9239-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa July 15, 2014, 9:29 p.m. UTC
This is a note to let you know that I have just added a patch titled

    s390/lowcore: reserve 96 bytes for IRB in lowcore

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.5.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

From cbe22fce600179338ceacbaf7ec6982fc0e702e8 Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Mon, 26 May 2014 21:55:08 +0200
Subject: s390/lowcore: reserve 96 bytes for IRB in lowcore

commit 993072ee67aa179c48c85eb19869804e68887d86 upstream.

The IRB might be 96 bytes if the extended-I/O-measurement facility is
used. This feature is currently not used by Linux, but struct irb
already has the emw defined. So let's make the irb in lowcore match the
size of the internal data structure to be future proof.
We also have to add a pad, to correctly align the paste.

The bigger irb field also circumvents a bug in some QEMU versions that
always write the emw field on test subchannel and therefore destroy the
paste definitions of this CPU. Running under these QEMU version broke
some timing functions in the VDSO and all users of these functions,
e.g. some JREs.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 arch/s390/include/asm/lowcore.h | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

--
1.9.1
diff mbox

Patch

diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index bbf8141..2bed4f0 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -142,9 +142,9 @@  struct _lowcore {
 	__u8	pad_0x02fc[0x0300-0x02fc];	/* 0x02fc */

 	/* Interrupt response block */
-	__u8	irb[64];			/* 0x0300 */
+	__u8	irb[96];			/* 0x0300 */

-	__u8	pad_0x0340[0x0e00-0x0340];	/* 0x0340 */
+	__u8	pad_0x0360[0x0e00-0x0360];	/* 0x0360 */

 	/*
 	 * 0xe00 contains the address of the IPL Parameter Information
@@ -288,12 +288,13 @@  struct _lowcore {
 	__u8	pad_0x03a0[0x0400-0x03a0];	/* 0x03a0 */

 	/* Interrupt response block. */
-	__u8	irb[64];			/* 0x0400 */
+	__u8	irb[96];			/* 0x0400 */
+	__u8	pad_0x0460[0x0480-0x0460];	/* 0x0460 */

 	/* Per cpu primary space access list */
-	__u32	paste[16];			/* 0x0440 */
+	__u32	paste[16];			/* 0x0480 */

-	__u8	pad_0x0480[0x0e00-0x0480];	/* 0x0480 */
+	__u8	pad_0x04c0[0x0e00-0x04c0];	/* 0x04c0 */

 	/*
 	 * 0xe00 contains the address of the IPL Parameter Information