| Message ID | 20210209185154.1037852-2-imbrenda@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: mvpg test | expand |
On Tue, 9 Feb 2021 19:51:52 +0100 Claudio Imbrenda <imbrenda@linux.ibm.com> wrote: > In most testcases, we enter problem state (userspace) just to test if a > privileged instruction causes a fault. In some cases, though, we need > to test if an instruction works properly in userspace. This means that > we do not expect a fault, and we need an orderly way to leave problem > state afterwards. > > This patch introduces a simple system based on the SVC instruction. > > Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > --- > lib/s390x/asm/arch_def.h | 5 +++++ > lib/s390x/interrupt.c | 12 ++++++++++-- > 2 files changed, 15 insertions(+), 2 deletions(-) Reviewed-by: Cornelia Huck <cohuck@redhat.com>
On 2/9/21 7:51 PM, Claudio Imbrenda wrote: > In most testcases, we enter problem state (userspace) just to test if a > privileged instruction causes a fault. In some cases, though, we need > to test if an instruction works properly in userspace. This means that > we do not expect a fault, and we need an orderly way to leave problem > state afterwards. > > This patch introduces a simple system based on the SVC instruction. > > Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > --- > lib/s390x/asm/arch_def.h | 5 +++++ > lib/s390x/interrupt.c | 12 ++++++++++-- > 2 files changed, 15 insertions(+), 2 deletions(-) > > diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h > index 9c4e330a..9902e9fe 100644 > --- a/lib/s390x/asm/arch_def.h > +++ b/lib/s390x/asm/arch_def.h > @@ -276,6 +276,11 @@ static inline void enter_pstate(void) > load_psw_mask(mask); > } > > +static inline void leave_pstate(void) > +{ > + asm volatile(" svc 1\n"); Magic constants being magic :-) > +} > + > static inline int stsi(void *addr, int fc, int sel1, int sel2) > { > register int r0 asm("0") = (fc << 28) | sel1; > diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c > index 1ce36073..59e01b1a 100644 > --- a/lib/s390x/interrupt.c > +++ b/lib/s390x/interrupt.c > @@ -188,6 +188,14 @@ int unregister_io_int_func(void (*f)(void)) > > void handle_svc_int(void) > { > - report_abort("Unexpected supervisor call interrupt: on cpu %d at %#lx", > - stap(), lc->svc_old_psw.addr); > + uint16_t code = lc->svc_int_code; > + > + switch (code) { > + case 1: > + lc->svc_old_psw.mask &= ~PSW_MASK_PSTATE; > + break; > + default: > + report_abort("Unexpected supervisor call interrupt: code %#x on cpu %d at %#lx", > + code, stap(), lc->svc_old_psw.addr); > + } > } >
On 09.02.21 19:51, Claudio Imbrenda wrote: > In most testcases, we enter problem state (userspace) just to test if a > privileged instruction causes a fault. In some cases, though, we need > to test if an instruction works properly in userspace. This means that > we do not expect a fault, and we need an orderly way to leave problem > state afterwards. > > This patch introduces a simple system based on the SVC instruction. > > Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > --- > lib/s390x/asm/arch_def.h | 5 +++++ > lib/s390x/interrupt.c | 12 ++++++++++-- > 2 files changed, 15 insertions(+), 2 deletions(-) > > diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h > index 9c4e330a..9902e9fe 100644 > --- a/lib/s390x/asm/arch_def.h > +++ b/lib/s390x/asm/arch_def.h > @@ -276,6 +276,11 @@ static inline void enter_pstate(void) > load_psw_mask(mask); > } > > +static inline void leave_pstate(void) > +{ > + asm volatile(" svc 1\n"); > +} > + > static inline int stsi(void *addr, int fc, int sel1, int sel2) > { > register int r0 asm("0") = (fc << 28) | sel1; > diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c > index 1ce36073..59e01b1a 100644 > --- a/lib/s390x/interrupt.c > +++ b/lib/s390x/interrupt.c > @@ -188,6 +188,14 @@ int unregister_io_int_func(void (*f)(void)) > > void handle_svc_int(void) > { > - report_abort("Unexpected supervisor call interrupt: on cpu %d at %#lx", > - stap(), lc->svc_old_psw.addr); > + uint16_t code = lc->svc_int_code; > + > + switch (code) { > + case 1: > + lc->svc_old_psw.mask &= ~PSW_MASK_PSTATE; > + break; > + default: > + report_abort("Unexpected supervisor call interrupt: code %#x on cpu %d at %#lx", > + code, stap(), lc->svc_old_psw.addr); > + } > } > Acked-by: David Hildenbrand <david@redhat.com>
diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h index 9c4e330a..9902e9fe 100644 --- a/lib/s390x/asm/arch_def.h +++ b/lib/s390x/asm/arch_def.h @@ -276,6 +276,11 @@ static inline void enter_pstate(void) load_psw_mask(mask); } +static inline void leave_pstate(void) +{ + asm volatile(" svc 1\n"); +} + static inline int stsi(void *addr, int fc, int sel1, int sel2) { register int r0 asm("0") = (fc << 28) | sel1; diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c index 1ce36073..59e01b1a 100644 --- a/lib/s390x/interrupt.c +++ b/lib/s390x/interrupt.c @@ -188,6 +188,14 @@ int unregister_io_int_func(void (*f)(void)) void handle_svc_int(void) { - report_abort("Unexpected supervisor call interrupt: on cpu %d at %#lx", - stap(), lc->svc_old_psw.addr); + uint16_t code = lc->svc_int_code; + + switch (code) { + case 1: + lc->svc_old_psw.mask &= ~PSW_MASK_PSTATE; + break; + default: + report_abort("Unexpected supervisor call interrupt: code %#x on cpu %d at %#lx", + code, stap(), lc->svc_old_psw.addr); + } }
In most testcases, we enter problem state (userspace) just to test if a privileged instruction causes a fault. In some cases, though, we need to test if an instruction works properly in userspace. This means that we do not expect a fault, and we need an orderly way to leave problem state afterwards. This patch introduces a simple system based on the SVC instruction. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> --- lib/s390x/asm/arch_def.h | 5 +++++ lib/s390x/interrupt.c | 12 ++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-)