Re: [kvm-unit-tests PATCH 1/4] s390x: sie: Add sie lib validity handling

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Thu, 29 Jul 2021 16:33:31 +0200
Janosch Frank <frankja@linux.ibm.com> wrote:

> On 7/29/21 4:11 PM, Claudio Imbrenda wrote:
> > On Thu, 29 Jul 2021 13:48:00 +0000
> > Janosch Frank <frankja@linux.ibm.com> wrote:
> >   
> >> Let's start off the SIE lib with validity handling code since that
> >> has the least amount of dependencies to other files.
> >>
> >> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> >> ---
> >>  lib/s390x/sie.c  | 41 +++++++++++++++++++++++++++++++++++++++++
> >>  lib/s390x/sie.h  |  3 +++
> >>  s390x/Makefile   |  1 +
> >>  s390x/mvpg-sie.c |  2 +-
> >>  s390x/sie.c      |  7 +------
> >>  5 files changed, 47 insertions(+), 7 deletions(-)
> >>  create mode 100644 lib/s390x/sie.c
> >>
> >> diff --git a/lib/s390x/sie.c b/lib/s390x/sie.c
> >> new file mode 100644
> >> index 00000000..9107519f
> >> --- /dev/null
> >> +++ b/lib/s390x/sie.c
> >> @@ -0,0 +1,41 @@
> >> +/* SPDX-License-Identifier: GPL-2.0-only */
> >> +/*
> >> + * Virtualization library that speeds up managing guests.
> >> + *
> >> + * Copyright (c) 2021 IBM Corp
> >> + *
> >> + * Authors:
> >> + *  Janosch Frank <frankja@linux.ibm.com>
> >> + */
> >> +
> >> +#include <asm/barrier.h>
> >> +#include <libcflat.h>
> >> +#include <sie.h>
> >> +
> >> +static bool validity_expected;
> >> +static uint16_t vir;
> >> +
> >> +void sie_expect_validity(void)
> >> +{
> >> +	validity_expected = true;
> >> +	vir = 0;
> >> +}
> >> +
> >> +void sie_check_validity(uint16_t vir_exp)
> >> +{
> >> +	report(vir_exp == vir, "VALIDITY: %x", vir);
> >> +	mb();  
> > 
> > why the barrier?  
> 
> That's left over, I'll remove it.

with the barrier removed:

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> >   
> >> +	vir = 0;
> >> +}
> >> +
> >> +void sie_handle_validity(struct vm *vm)
> >> +{
> >> +	if (vm->sblk->icptcode != ICPT_VALIDITY)
> >> +		return;
> >> +
> >> +	vir = vm->sblk->ipb >> 16;
> >> +
> >> +	if (!validity_expected)
> >> +		report_abort("VALIDITY: %x", vir);
> >> +	validity_expected = false;
> >> +}
> >> diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h
> >> index 6ba858a2..7ff98d2d 100644
> >> --- a/lib/s390x/sie.h
> >> +++ b/lib/s390x/sie.h
> >> @@ -197,5 +197,8 @@ struct vm {
> >>  extern void sie_entry(void);
> >>  extern void sie_exit(void);
> >>  extern void sie64a(struct kvm_s390_sie_block *sblk, struct
> >> vm_save_area *save_area); +void sie_expect_validity(void);
> >> +void sie_check_validity(uint16_t vir_exp);
> >> +void sie_handle_validity(struct vm *vm);
> >>  
> >>  #endif /* _S390X_SIE_H_ */
> >> diff --git a/s390x/Makefile b/s390x/Makefile
> >> index 6565561b..ef8041a6 100644
> >> --- a/s390x/Makefile
> >> +++ b/s390x/Makefile
> >> @@ -71,6 +71,7 @@ cflatobjs += lib/s390x/css_dump.o
> >>  cflatobjs += lib/s390x/css_lib.o
> >>  cflatobjs += lib/s390x/malloc_io.o
> >>  cflatobjs += lib/s390x/uv.o
> >> +cflatobjs += lib/s390x/sie.o
> >>  
> >>  OBJDIRS += lib/s390x
> >>  
> >> diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
> >> index 5e70f591..2ac91eec 100644
> >> --- a/s390x/mvpg-sie.c
> >> +++ b/s390x/mvpg-sie.c
> >> @@ -39,7 +39,7 @@ static void sie(struct vm *vm)
> >>  
> >>  	while (vm->sblk->icptcode == 0) {
> >>  		sie64a(vm->sblk, &vm->save_area);
> >> -		assert(vm->sblk->icptcode != ICPT_VALIDITY);
> >> +		sie_handle_validity(vm);
> >>  	}
> >>  	vm->save_area.guest.grs[14] = vm->sblk->gg14;
> >>  	vm->save_area.guest.grs[15] = vm->sblk->gg15;
> >> diff --git a/s390x/sie.c b/s390x/sie.c
> >> index 134d3c4f..5c798a9e 100644
> >> --- a/s390x/sie.c
> >> +++ b/s390x/sie.c
> >> @@ -24,17 +24,12 @@ static u8 *guest;
> >>  static u8 *guest_instr;
> >>  static struct vm vm;
> >>  
> >> -static void handle_validity(struct vm *vm)
> >> -{
> >> -	report(0, "VALIDITY: %x", vm->sblk->ipb >> 16);
> >> -}
> >>  
> >>  static void sie(struct vm *vm)
> >>  {
> >>  	while (vm->sblk->icptcode == 0) {
> >>  		sie64a(vm->sblk, &vm->save_area);
> >> -		if (vm->sblk->icptcode == ICPT_VALIDITY)
> >> -			handle_validity(vm);
> >> +		sie_handle_validity(vm);
> >>  	}
> >>  	vm->save_area.guest.grs[14] = vm->sblk->gg14;
> >>  	vm->save_area.guest.grs[15] = vm->sblk->gg15;  
> >   
>