Patch "Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"" has been added to the 4.6-stable tree

Patch "Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"" has been added to the 4.6-stable tree

[gregkh]

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

    Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"

to the 4.6-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:
     revert-s390-kdump-clear-subchannel-id-to-signal-non-ccw-scsi-ipl.patch
and it can be found in the queue-4.6 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 5419447e2142d6ed68c9f5c1a28630b3a290a845 Mon Sep 17 00:00:00 2001
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Date: Mon, 13 Jun 2016 17:03:48 +0200
Subject: Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"

From: Michael Holzheu <holzheu@linux.vnet.ibm.com>

commit 5419447e2142d6ed68c9f5c1a28630b3a290a845 upstream.

This reverts commit 852ffd0f4e23248b47531058e531066a988434b5.

There are use cases where an intermediate boot kernel (1) uses kexec
to boot the final production kernel (2). For this scenario we should
provide the original boot information to the production kernel (2).
Therefore clearing the boot information during kexec() should not
be done.

Reported-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/s390/kernel/ipl.c |    7 -------
 1 file changed, 7 deletions(-)

--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -2064,12 +2064,5 @@ void s390_reset_system(void)
 	S390_lowcore.program_new_psw.addr =
 		(unsigned long) s390_base_pgm_handler;
 
-	/*
-	 * Clear subchannel ID and number to signal new kernel that no CCW or
-	 * SCSI IPL has been done (for kexec and kdump)
-	 */
-	S390_lowcore.subchannel_id = 0;
-	S390_lowcore.subchannel_nr = 0;
-
 	do_reset_calls();
 }


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

queue-4.6/revert-s390-kdump-clear-subchannel-id-to-signal-non-ccw-scsi-ipl.patch