Commit 99e639b7 authored Oct 31, 2012 by Heiko Carstens Committed by Martin Schwidefsky Nov 06, 2012

s390/sclp: fix addressing mode clobber



The early mini sclp driver may be called in zArch mode either in
31 or 64 bit addressing mode.
If called in 31 bit addressing mode the new external interrupt psw
however would switch to 64 bit addressing mode. This would cause an
addressing exception within the interrupt handler, since the code
didn't expect the zArch/31 bit addressing mode combination.

Fix this by setting the new psw addressing mode bits so they fit
the current addressing mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent 619506d5

arch/s390/kernel/sclp.S

+7 −1

Original line number	Diff line number	Diff line
		@@ -44,6 +44,12 @@ _sclp_wait_int:
		#endif
		mvc .LoldpswS1-.LbaseS1(16,%r13),0(%r8)
		mvc 0(16,%r8),0(%r9)
		#ifdef CONFIG_64BIT
		epsw %r6,%r7 # set current addressing mode
		nill %r6,0x1 # in new psw (31 or 64 bit mode)
		nilh %r7,0x8000
		stm %r6,%r7,0(%r8)
		#endif
		lhi %r6,0x0200 # cr mask for ext int (cr0.54)
		ltr %r2,%r2
		jz .LsetctS1
		@@ -87,7 +93,7 @@ _sclp_wait_int:
		.long 0x00080000, 0x80000000+.LwaitS1 # PSW to handle ext int
		#ifdef CONFIG_64BIT
		.LextpswS1_64:
		.quad 0x0000000180000000, .LwaitS1 # PSW to handle ext int, 64 bit
		.quad 0, .LwaitS1 # PSW to handle ext int, 64 bit
		#endif
		.LwaitpswS1:
		.long 0x010a0000, 0x00000000+.LloopS1 # PSW to wait for ext int