On Tue, 2022-05-17 at 16:52 +0200, Claudio Imbrenda wrote: > On Tue, 17 May 2022 13:56:07 +0200 > Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> wrote: > > > Test that key-controlled protection does not apply to diag 308. > > > > Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> > > --- > > s390x/skey.c | 26 ++++++++++++++++++++++++++ > > 1 file changed, 26 insertions(+) > > > > diff --git a/s390x/skey.c b/s390x/skey.c > > index 60ae8158..c2d28ffd 100644 > > --- a/s390x/skey.c > > +++ b/s390x/skey.c > > @@ -285,6 +285,31 @@ static void test_store_cpu_address(void) > > report_prefix_pop(); > > } > > > > +static void test_diag_308(void) > > +{ > > + uint16_t response; > > + uint32_t (*ipib)[1024] = (void *)pagebuf; > > why not just uint32_t *ipib = (void *)pagebuf; ? > > > + > > + report_prefix_push("DIAG 308"); > > + (*ipib)[0] = 0; /* Invalid length */ In an intermediate version I had memset(ipib, 0, sizeof(*ipib)); Also, if I could specify that the asm writes to a memory location that is specified via an address in a register without displacement, it would tell the compiler what memory would be read. Alas that is not possible (correct me if I'm wrong), so I actually would do WRITE_ONCE(ipib[0], 0) (an get rid of the pointer to array) > > then you can simply do: > > ipib[0] = 0; > > > + set_storage_key(ipib, 0x28, 0); > > + /* key-controlled protection does not apply */ > > + asm volatile ( > > + "lr %%r2,%[ipib]\n\t" > > + "spka 0x10\n\t" > > + "diag %%r2,%[code],0x308\n\t" > > + "spka 0\n\t" > > + "lr %[response],%%r3\n" > > + : [response] "=d" (response) > > + : [ipib] "d" (ipib), > > + [code] "d" (5) > > + : "%r2", "%r3" > > + ); > > + report(response == 0x402, "no exception on fetch, response: invalid IPIB"); > > + set_storage_key(ipib, 0x00, 0); > > + report_prefix_pop(); > > +} > > + > > /* > > * Perform CHANNEL SUBSYSTEM CALL (CHSC) instruction while temporarily executing > > * with access key 1. > > @@ -714,6 +739,7 @@ int main(void) > > test_chg(); > > test_test_protection(); > > test_store_cpu_address(); > > + test_diag_308(); > > test_channel_subsystem_call(); > > > > setup_vm(); >