[PATCH v1 1/2] s390/entry: Pass the asce as parameter to sie64a()

Claudio Imbrenda
2024-07-03T15:59:10Z

Pass the guest ASCE explicitly as parameter, instead of having sie64a()
take it from lowcore.

This removes hidden state from lowcore, and makes things look cleaner.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 7 ++++---
arch/s390/include/asm/stacktrace.h | 1 +
arch/s390/kernel/asm-offsets.c | 1 +
arch/s390/kernel/entry.S | 8 +++-----
arch/s390/kvm/kvm-s390.c | 3 ++-
arch/s390/kvm/vsie.c | 2 +-
6 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 95990461888f..2d4e3f50a823 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -1029,11 +1029,12 @@ void kvm_arch_crypto_clear_masks(struct kvm *kvm);
void kvm_arch_crypto_set_masks(struct kvm *kvm, unsigned long *apm,
unsigned long *aqm, unsigned long *adm);

-int __sie64a(phys_addr_t sie_block_phys, struct kvm_s390_sie_block *sie_block, u64 *rsa);
+int __sie64a(phys_addr_t sie_block_phys, struct kvm_s390_sie_block *sie_block, u64 *rsa,
+ unsigned long gasce);

-static inline int sie64a(struct kvm_s390_sie_block *sie_block, u64 *rsa)
+static inline int sie64a(struct kvm_s390_sie_block *sie_block, u64 *rsa, unsigned long gasce)
{
- return __sie64a(virt_to_phys(sie_block), sie_block, rsa);
+ return __sie64a(virt_to_phys(sie_block), sie_block, rsa, gasce);
}

extern char sie_exit;
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index 85b6738b826a..1d5ca13dc90f 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -65,6 +65,7 @@ struct stack_frame {
unsigned long sie_reason;
unsigned long sie_flags;
unsigned long sie_control_block_phys;
+ unsigned long sie_guest_asce;
};
};
unsigned long gprs[10];
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index f55979f64d49..26bb45d0e6f1 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -63,6 +63,7 @@ int main(void)
OFFSET(__SF_SIE_REASON, stack_frame, sie_reason);
OFFSET(__SF_SIE_FLAGS, stack_frame, sie_flags);
OFFSET(__SF_SIE_CONTROL_PHYS, stack_frame, sie_control_block_phys);
+ OFFSET(__SF_SIE_GUEST_ASCE, stack_frame, sie_guest_asce);
DEFINE(STACK_FRAME_OVERHEAD, sizeof(struct stack_frame));
BLANK();
OFFSET(__SFUSER_BACKCHAIN, stack_frame_user, back_chain);
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 60cf917a7122..454b6b92c7f8 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -179,6 +179,7 @@ SYM_FUNC_END(__switch_to_asm)
* %r2 pointer to sie control block phys
* %r3 pointer to sie control block virt
* %r4 guest register save area
+ * %r5 guest asce
*/
SYM_FUNC_START(__sie64a)
stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
@@ -186,15 +187,12 @@ SYM_FUNC_START(__sie64a)
stg %r2,__SF_SIE_CONTROL_PHYS(%r15) # save sie block physical..
stg %r3,__SF_SIE_CONTROL(%r15) # ...and virtual addresses
stg %r4,__SF_SIE_SAVEAREA(%r15) # save guest register save area
+ stg %r5,__SF_SIE_GUEST_ASCE(%r15) # save guest asce
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
lmg %r0,%r13,0(%r4) # load guest gprs 0-13
- lg %r14,__LC_GMAP # get gmap pointer
- ltgr %r14,%r14
- jz .Lsie_gmap
oi __LC_CPU_FLAGS+7,_CIF_SIE
- lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
-.Lsie_gmap:
+ lctlg %c1,%c1,__SF_SIE_GUEST_ASCE(%r15) # load primary asce
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...
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 82e9631cd9ef..148dff562386 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4829,7 +4829,8 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
sizeof(sie_page->pv_grregs));
}
exit_reason = sie64a(vcpu->arch.sie_block,
- vcpu->run->s.regs.gprs);
+ vcpu->run->s.regs.gprs,
+ gmap_get_enabled()->asce);
if (kvm_s390_pv_cpu_is_protected(vcpu)) {
memcpy(vcpu->run->s.regs.gprs,
sie_page->pv_grregs,
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index c9ecae830634..97a70c2b83ee 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -1150,7 +1150,7 @@ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
vcpu->arch.sie_block->prog0c |= PROG_IN_SIE;
barrier();
if (!kvm_s390_vcpu_sie_inhibited(vcpu))
- rc = sie64a(scb_s, vcpu->run->s.regs.gprs);
+ rc = sie64a(scb_s, vcpu->run->s.regs.gprs, gmap_get_enabled()->asce);
barrier();
vcpu->arch.sie_block->prog0c &= ~PROG_IN_SIE;

--
2.45.2