linux-kernel - [33/55] [S390] kvm-390: Let kernel exit SIE instruction on work

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20110429185655.774296728@clark.kroah.org>
Date:	Fri, 29 Apr 2011 11:55:56 -0700
From:	Greg KH <gregkh@...e.de>
To:	linux-kernel@...r.kernel.org, stable@...nel.org
Cc:	stable-review@...nel.org, torvalds@...ux-foundation.org,
	akpm@...ux-foundation.org, alan@...rguk.ukuu.org.uk,
	Carsten Otte <cotte@...ibm.com>,
	Christian Borntraeger <borntraeger@...ibm.com>,
	Martin Schwidefsky <schwidefsky@...ibm.com>
Subject: [33/55] [S390] kvm-390: Let kernel exit SIE instruction on work

2.6.38-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Carsten Otte <cotte@...ibm.com>

commit 9ff4cfb3fcfd48b49fdd9be7381b3be340853aa4 upstream.

From: Christian Borntraeger <borntraeger@...ibm.com>

This patch fixes the sie exit on interrupts. The low level
interrupt handler returns to the PSW address in pt_regs and not
to the PSW address in the lowcore.
Without this fix a cpu bound guest might never leave guest state
since the host interrupt handler would blindly return to the
SIE instruction, even on need_resched and friends.

Signed-off-by: Carsten Otte <cotte@...ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@...ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@...ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>

---
 arch/s390/kvm/sie64a.S |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/s390/kvm/sie64a.S
+++ b/arch/s390/kvm/sie64a.S
@@ -48,10 +48,10 @@ sie_irq_handler:
 	tm	__TI_flags+7(%r2),_TIF_EXIT_SIE
 	jz	0f
 	larl	%r2,sie_exit			# work pending, leave sie
-	stg	%r2,__LC_RETURN_PSW+8
+	stg	%r2,SPI_PSW+8(0,%r15)
 	br	%r14
 0:	larl	%r2,sie_reenter			# re-enter with guest id
-	stg	%r2,__LC_RETURN_PSW+8
+	stg	%r2,SPI_PSW+8(0,%r15)
 1:	br	%r14
 
 /*


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/