Commit 92fa7a13 authored by Martin Schwidefsky's avatar Martin Schwidefsky
Browse files

s390/kvm: improve stack frame constants in entry.S 



The code in sie64a uses the stack frame passed to the function to store
some temporary data in the empty1 array (see struct stack_frame in
asm/processor.h.

Replace the __SF_EMPTY+x constants with a properly defined offset:
s/__SF_EMPTY/__SF_SIE_CONTROL/, s/__SF_EMPTY+8/__SF_SIE_SAVEAREA/,
s/__SF_EMPTY+16/__SF_SIE_REASON/, s/__SF_EMPTY+24/__SF_SIE_FLAGS/.

Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent e5b98199

arch/s390/kernel/asm-offsets.c

+1 −0
Original line number Diff line number Diff line
@@ -63,6 +63,7 @@ int main(void) 
	OFFSET(__SF_SIE_CONTROL, stack_frame, empty1[0]);

	OFFSET(__SF_SIE_SAVEAREA, stack_frame, empty1[1]);

	OFFSET(__SF_SIE_REASON, stack_frame, empty1[2]);

	OFFSET(__SF_SIE_FLAGS, stack_frame, empty1[3]);

	BLANK();

	/* timeval/timezone offsets for use by vdso */

	OFFSET(__VDSO_UPD_COUNT, vdso_data, tb_update_count);

arch/s390/kernel/entry.S

+13 −13
Original line number Diff line number Diff line
@@ -297,10 +297,10 @@ ENTRY(__switch_to) 
ENTRY(sie64a)

	stmg	%r6,%r14,__SF_GPRS(%r15)	# save kernel registers

	lg	%r12,__LC_CURRENT

	stg	%r2,__SF_EMPTY(%r15)		# save control block pointer

	stg	%r3,__SF_EMPTY+8(%r15)		# save guest register save area

	xc	__SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # reason code = 0

	mvc	__SF_EMPTY+24(8,%r15),__TI_flags(%r12) # copy thread flags

	stg	%r2,__SF_SIE_CONTROL(%r15)	# save control block pointer

	stg	%r3,__SF_SIE_SAVEAREA(%r15)	# save guest register save area

	xc	__SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0

	mvc	__SF_SIE_FLAGS(8,%r15),__TI_flags(%r12) # copy thread flags

	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU		# load guest fp/vx registers ?

	jno	.Lsie_load_guest_gprs

	brasl	%r14,load_fpu_regs		# load guest fp/vx regs
@@ -311,18 +311,18 @@ ENTRY(sie64a) 
	jz	.Lsie_gmap

	lctlg	%c1,%c1,__GMAP_ASCE(%r14)	# load primary asce

.Lsie_gmap:

	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer

	lg	%r14,__SF_SIE_CONTROL(%r15)	# get control block pointer

	oi	__SIE_PROG0C+3(%r14),1		# we are going into SIE now

	tm	__SIE_PROG20+3(%r14),3		# last exit...

	jnz	.Lsie_skip

	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU

	jo	.Lsie_skip			# exit if fp/vx regs changed

	BPEXIT	__SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

	BPEXIT	__SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

.Lsie_entry:

	sie	0(%r14)

.Lsie_exit:

	BPOFF

	BPENTER	__SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

	BPENTER	__SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

.Lsie_skip:

	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE

	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
@@ -341,7 +341,7 @@ ENTRY(sie64a) 
	nopr	7

	.globl sie_exit

sie_exit:

	lg	%r14,__SF_EMPTY+8(%r15)		# load guest register save area

	lg	%r14,__SF_SIE_SAVEAREA(%r15)	# load guest register save area

	stmg	%r0,%r13,0(%r14)		# save guest gprs 0-13

	xgr	%r0,%r0				# clear guest registers to

	xgr	%r1,%r1				# prevent speculative use
@@ -350,11 +350,11 @@ sie_exit: 
	xgr	%r4,%r4

	xgr	%r5,%r5

	lmg	%r6,%r14,__SF_GPRS(%r15)	# restore kernel registers

	lg	%r2,__SF_EMPTY+16(%r15)		# return exit reason code

	lg	%r2,__SF_SIE_REASON(%r15)	# return exit reason code

	BR_R1USE_R14

.Lsie_fault:

	lghi	%r14,-EFAULT

	stg	%r14,__SF_EMPTY+16(%r15)	# set exit reason code

	stg	%r14,__SF_SIE_REASON(%r15)	# set exit reason code

	j	sie_exit



	EX_TABLE(.Lrewind_pad6,.Lsie_fault)
@@ -643,7 +643,7 @@ ENTRY(pgm_check_handler) 
	slg	%r14,BASED(.Lsie_critical_start)

	clg	%r14,BASED(.Lsie_critical_length)

	jhe	0f

	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer

	lg	%r14,__SF_SIE_CONTROL(%r15)	# get control block pointer

	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE

	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce

	larl	%r9,sie_exit			# skip forward to sie_exit
@@ -1353,8 +1353,8 @@ cleanup_critical: 
	clg     %r9,BASED(.Lsie_crit_mcck_length)

	jh      1f

	oi      __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST

1:	BPENTER __SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

	lg	%r9,__SF_EMPTY(%r15)		# get control block pointer

1:	BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)

	lg	%r9,__SF_SIE_CONTROL(%r15)	# get control block pointer

	ni	__SIE_PROG0C+3(%r9),0xfe	# no longer in SIE

	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce

	larl	%r9,sie_exit			# skip forward to sie_exit

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