Re: [PATCH v5 04/12] xen/arm: add SVE exception class handling

[Luca Fancellu <Luca.Fancellu@arm.com>]

>> --- a/xen/arch/arm/traps.c
>> +++ b/xen/arch/arm/traps.c
>> @@ -2160,6 +2160,13 @@ void do_trap_guest_sync(struct cpu_user_regs *regs)
>>          perfc_incr(trap_sysreg);
>>          do_sysreg(regs, hsr);
>>          break;
>> +    case HSR_EC_SVE:
>> +        GUEST_BUG_ON(regs_mode_is_32bit(regs));
>> +        gprintk(XENLOG_WARNING,
>> +                "Domain id %d tried to use SVE while not allowed\n",
>> +                current->domain->domain_id);
> 
> gprintk() will already print the domain/vCPU for you. Also, if you want to print a domain ID, then you should use ("%pd", d) rather than ("%d", d->domain_id).

Ok I’ll change it to:

gprintk(XENLOG_WARNING, "Domain tried to use SVE while not allowed\n");

> 
>> +        inject_undef_exception(regs, hsr);
>> +        break;
>>  #endif
>>        case HSR_EC_INSTR_ABORT_LOWER_EL:
>> @@ -2189,6 +2196,11 @@ void do_trap_hyp_sync(struct cpu_user_regs *regs)
>>      case HSR_EC_BRK:
>>          do_trap_brk(regs, hsr);
>>          break;
>> +    case HSR_EC_SVE:
>> +        /* An SVE exception is a bug somewhere in hypervisor code */
>> +        printk("SVE trap at EL2.\n");
>> +        do_unexpected_trap("Hypervisor", regs);
> 
> I think it would be better if you pass "SVE trap at EL2" as a string rather than adding your own printk above.

Ok I’ll remove the printk and do just do_unexpected_trap("SVE trap at EL2", regs);

> 
>> +        break;
>>  #endif
>>      case HSR_EC_DATA_ABORT_CURR_EL:
>>      case HSR_EC_INSTR_ABORT_CURR_EL:
> 
> Cheers,
> 
> -- 
> Julien Grall