On Wed, 17 Jan 2018 16:37:37 +0100
David Hildenbrand <da...@redhat.com> wrote:
> On 12.01.2018 13:54, David Hildenbrand wrote:
> > CC == 2 can only happen due to a protection exception, not if memory is
> > not available (PGM_ADDRESSING). So all PGM_ADDRESSING exceptions have to
> > be forwarded to the guest.
> >
> > Since the initial definition of TEST PROTECTION, we now read globals
> > (e.g. PSW mask), so we have to correctly mark the instruction
> > (otherwise, e.g. booting fedora 27 fails).
> >
> > Also, the architecture explicitly specifies which exceptions are
> > forwarded to the guest, this makes the code a little nicer.
> >
> > Signed-off-by: David Hildenbrand <da...@redhat.com>
> > ---
> > target/s390x/cpu.h | 2 ++
> > target/s390x/helper.h | 2 +-
> > target/s390x/EM_helper.c | 41 +++++++++++++++++++----------------------
> > 3 files changed, 22 insertions(+), 23 deletions(-)
> >
> > diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
> > index 1a8b6b9ae9..915bccbc75 100644
> > --- a/target/s390x/cpu.h
> > +++ b/target/s390x/cpu.h
> > @@ -759,6 +759,8 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr,
> > uint8_t ar, void *hostbuf,
> > s390_cpu_virt_mem_rw(cpu, laddr, ar, dest, len, false)
> > #define s390_cpu_virt_mem_write(cpu, laddr, ar, dest, len) \
> > s390_cpu_virt_mem_rw(cpu, laddr, ar, dest, len, true)
> > +#define s390_cpu_virt_mem_check_read(cpu, laddr, ar, len) \
> > + s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, false)
> > #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len) \
> > s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
> > void s390_cpu_virt_mem_handle_exc(S390CPU *cpu, uintptr_t ra);
> > diff --git a/target/s390x/helper.h b/target/s390x/helper.h
> > index 26c1b07b44..59a1d9869b 100644
> > --- a/target/s390x/helper.h
> > +++ b/target/s390x/helper.h
> > @@ -137,7 +137,7 @@ DEF_HELPER_FLAGS_4(lctlg, TCG_CALL_NO_WG, void, env,
> > i32, i64, i32)
> > DEF_HELPER_FLAGS_4(stctl, TCG_CALL_NO_WG, void, env, i32, i64, i32)
> > DEF_HELPER_FLAGS_4(stctg, TCG_CALL_NO_WG, void, env, i32, i64, i32)
> > DEF_HELPER_FLAGS_2(testblock, TCG_CALL_NO_WG, i32, env, i64)
> > -DEF_HELPER_FLAGS_3(tprot, TCG_CALL_NO_RWG, i32, env, i64, i64)
> > +DEF_HELPER_FLAGS_3(tprot, TCG_CALL_NO_WG, i32, env, i64, i64)
> > DEF_HELPER_FLAGS_2(iske, TCG_CALL_NO_RWG_SE, i64, env, i64)
> > DEF_HELPER_FLAGS_3(sske, TCG_CALL_NO_RWG, void, env, i64, i64)
> > DEF_HELPER_FLAGS_2(rrbe, TCG_CALL_NO_RWG, i32, env, i64)
> > diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
> > index 359e446c6f..c957febc6d 100644
> > --- a/target/s390x/mem_helper.c
> > +++ b/target/s390x/mem_helper.c
> > @@ -1730,34 +1730,31 @@ uint32_t HELPER(tprot)(CPUS390XState *env, uint64_t
> > a1, uint64_t a2)
> > /* Fetching permitted; storing permitted */
> > return 0;
> > }
> > +
> > + if (env->int_pgm_code == PGM_PROTECTION) {
> > + /* retry if reading is possible */
> > + cs->exception_index = 0;
> > + if (!s390_cpu_virt_mem_check_read(cpu, a1, 0, 1)) {
> > + /* Fetching permitted; storing not permitted */
> > + return 1;
> > + }
> > + }
> > +
> > switch (env->int_pgm_code) {
> > case PGM_PROTECTION:
> > - /* Fetching permitted; storing not permitted */
> > - cs->exception_index = 0;
> > - return 1;
> > - case PGM_ADDRESSING:
> > /* Fetching not permitted; storing not permitted */
> > cs->exception_index = 0;
> > return 2;
> > - case PGM_ASCE_TYPE:
> > - case PGM_REG_FIRST_TRANS:
> > - case PGM_REG_SEC_TRANS:
> > - case PGM_REG_THIRD_TRANS:
> > - case PGM_SEGMENT_TRANS:
> > - case PGM_PAGE_TRANS:
> > - case PGM_ALET_SPEC:
> > - case PGM_ALEN_SPEC:
> > - case PGM_ALE_SEQ:
> > - case PGM_ASTE_VALID:
> > - case PGM_ASTE_SEQ:
> > - case PGM_EXT_AUTH:
> > - /* Translation not available */
> > - cs->exception_index = 0;
> > - return 3;
> > + case PGM_ADDRESSING:
> > + case PGM_TRANS_SPEC:
> > + /* exceptions forwarded to the guest */
> > + s390_cpu_virt_mem_handle_exc(cpu, GETPC());
> > + return 0;
> > }
> > - /* any other exception is forwarded to the guest */
> > - s390_cpu_virt_mem_handle_exc(cpu, GETPC());
> > - return 0;
> > +
> > + /* Translation not available */
> > + cs->exception_index = 0;
> > + return 3;
> > }
> >
> > /* insert storage key extended */
> >
>
> Ping, this is certainly better than the current (queued) state. Would
> love to see some review. But if nobody volunteers to read the PoP, I
> think my current use case (Linux and kvm-unit-tests) have to be
> sufficient for now.
I'm a bit low on review cycles, unfortunately.
I guess I will just queue this for the next batch if nobody speaks up
to the contrary.
