Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 90305465 authored by Martin Schwidefsky's avatar Martin Schwidefsky Committed by Greg Kroah-Hartman
Browse files

s390/kernel: use expoline for indirect branches 



[ Upstream commit c50c84c3ac4d5db683904bdb3257798b6ef980ae ]

The assember code in arch/s390/kernel uses a few more indirect branches
which need to be done with execute trampolines for CONFIG_EXPOLINE=y.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5ed6 ("s390: introduce execute-trampolines for branches")
Reviewed-by: default avatarHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 5ce9dc0f

arch/s390/kernel/base.S

+14 −10
Original line number Diff line number Diff line
@@ -8,18 +8,22 @@ 


#include <linux/linkage.h>

#include <asm/asm-offsets.h>

#include <asm/nospec-insn.h>

#include <asm/ptrace.h>

#include <asm/sigp.h>



	GEN_BR_THUNK %r9

	GEN_BR_THUNK %r14



ENTRY(s390_base_mcck_handler)

	basr	%r13,0

0:	lg	%r15,__LC_PANIC_STACK	# load panic stack

	aghi	%r15,-STACK_FRAME_OVERHEAD

	larl	%r1,s390_base_mcck_handler_fn

	lg	%r1,0(%r1)

	ltgr	%r1,%r1

	lg	%r9,0(%r1)

	ltgr	%r9,%r9

	jz	1f

	basr	%r14,%r1

	BASR_EX	%r14,%r9

1:	la	%r1,4095

	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)

	lpswe	__LC_MCK_OLD_PSW
@@ -36,10 +40,10 @@ ENTRY(s390_base_ext_handler) 
	basr	%r13,0

0:	aghi	%r15,-STACK_FRAME_OVERHEAD

	larl	%r1,s390_base_ext_handler_fn

	lg	%r1,0(%r1)

	ltgr	%r1,%r1

	lg	%r9,0(%r1)

	ltgr	%r9,%r9

	jz	1f

	basr	%r14,%r1

	BASR_EX	%r14,%r9

1:	lmg	%r0,%r15,__LC_SAVE_AREA_ASYNC

	ni	__LC_EXT_OLD_PSW+1,0xfd	# clear wait state bit

	lpswe	__LC_EXT_OLD_PSW
@@ -56,10 +60,10 @@ ENTRY(s390_base_pgm_handler) 
	basr	%r13,0

0:	aghi	%r15,-STACK_FRAME_OVERHEAD

	larl	%r1,s390_base_pgm_handler_fn

	lg	%r1,0(%r1)

	ltgr	%r1,%r1

	lg	%r9,0(%r1)

	ltgr	%r9,%r9

	jz	1f

	basr	%r14,%r1

	BASR_EX	%r14,%r9

	lmg	%r0,%r15,__LC_SAVE_AREA_SYNC

	lpswe	__LC_PGM_OLD_PSW

1:	lpswe	disabled_wait_psw-0b(%r13)
@@ -116,7 +120,7 @@ ENTRY(diag308_reset) 
	larl	%r4,.Lcontinue_psw	# Restore PSW flags

	lpswe	0(%r4)

.Lcontinue:

	br	%r14

	BR_EX	%r14

.align 16

.Lrestart_psw:

	.long	0x00080000,0x80000000 + .Lrestart_part2

arch/s390/kernel/reipl.S

+4 −1
Original line number Diff line number Diff line
@@ -6,8 +6,11 @@ 


#include <linux/linkage.h>

#include <asm/asm-offsets.h>

#include <asm/nospec-insn.h>

#include <asm/sigp.h>



	GEN_BR_THUNK %r14



#

# store_status

#
@@ -62,7 +65,7 @@ ENTRY(store_status) 
	st	%r3,__LC_PSW_SAVE_AREA-SAVE_AREA_BASE + 4(%r1)

	larl	%r2,store_status

	stg	%r2,__LC_PSW_SAVE_AREA-SAVE_AREA_BASE + 8(%r1)

	br	%r14

	BR_EX	%r14



	.section .bss

	.align	8

arch/s390/kernel/swsusp.S

+6 −4
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <asm/ptrace.h>

#include <asm/thread_info.h>

#include <asm/asm-offsets.h>

#include <asm/nospec-insn.h>

#include <asm/sigp.h>



/*
@@ -23,6 +24,8 @@ 
 * (see below) in the resume process.

 * This function runs with disabled interrupts.

 */

	GEN_BR_THUNK %r14



	.section .text

ENTRY(swsusp_arch_suspend)

	stmg	%r6,%r15,__SF_GPRS(%r15)
@@ -102,7 +105,7 @@ ENTRY(swsusp_arch_suspend) 
	spx	0x318(%r1)

	lmg	%r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)

	lghi	%r2,0

	br	%r14

	BR_EX	%r14



/*

 * Restore saved memory image to correct place and restore register context.
@@ -196,11 +199,10 @@ pgm_check_entry: 
	larl	%r15,init_thread_union

	ahi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER)

	larl	%r2,.Lpanic_string

	larl	%r3,_sclp_print_early

	lghi	%r1,0

	sam31

	sigp	%r1,%r0,SIGP_SET_ARCHITECTURE

	basr	%r14,%r3

	brasl	%r14,_sclp_print_early

	larl	%r3,.Ldisabled_wait_31

	lpsw	0(%r3)

4:
@@ -266,7 +268,7 @@ restore_registers: 
	/* Return 0 */

	lmg	%r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)

	lghi	%r2,0

	br	%r14

	BR_EX	%r14



	.section .data..nosave,"aw",@progbits

	.align	8