Commit 361f6ec2 authored by Sven Schnelle's avatar Sven Schnelle Committed by Vasily Gorbik
Browse files

s390/entry: Make system_call() ready for lowcore relocation 



In preparation of having lowcore at different address than zero,
add the base register to all lowcore accesses in system_call().

Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarSven Schnelle <svens@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 9b3dcae1

arch/s390/kernel/entry.S

+11 −10
Original line number Diff line number Diff line
@@ -264,14 +264,15 @@ EXPORT_SYMBOL(sie_exit) 
 */



SYM_CODE_START(system_call)

	stpt	__LC_SYS_ENTER_TIMER

	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC

	STMG_LC	%r8,%r15,__LC_SAVE_AREA_SYNC

	GET_LC	%r13

	stpt	__LC_SYS_ENTER_TIMER(%r13)

	BPOFF

	lghi	%r14,0

.Lsysc_per:

	STBEAR	__LC_LAST_BREAK

	lctlg	%c1,%c1,__LC_KERNEL_ASCE

	lg	%r15,__LC_KERNEL_STACK

	STBEAR	__LC_LAST_BREAK(%r13)

	lctlg	%c1,%c1,__LC_KERNEL_ASCE(%r13)

	lg	%r15,__LC_KERNEL_STACK(%r13)

	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)

	stmg	%r0,%r7,STACK_FRAME_OVERHEAD+__PT_R0(%r15)

	# clear user controlled register to prevent speculative use
@@ -286,17 +287,17 @@ SYM_CODE_START(system_call) 
	xgr	%r10,%r10

	xgr	%r11,%r11

	la	%r2,STACK_FRAME_OVERHEAD(%r15)	# pointer to pt_regs

	mvc	__PT_R8(64,%r2),__LC_SAVE_AREA_SYNC

	MBEAR	%r2,%r0

	mvc	__PT_R8(64,%r2),__LC_SAVE_AREA_SYNC(%r13)

	MBEAR	%r2,%r13

	lgr	%r3,%r14

	brasl	%r14,__do_syscall

	STACKLEAK_ERASE

	lctlg	%c1,%c1,__LC_USER_ASCE

	mvc	__LC_RETURN_PSW(16),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)

	lctlg	%c1,%c1,__LC_USER_ASCE(%r13)

	mvc	__LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)

	BPON

	LBEAR	STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)

	stpt	__LC_EXIT_TIMER(%r13)

	lmg	%r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)

	stpt	__LC_EXIT_TIMER

	LPSWEY	__LC_RETURN_PSW,__LC_RETURN_LPSWE

SYM_CODE_END(system_call)