linux-kernel - Re: [PATCH v8 04/22] s390/zcrypt: Integrate ap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <10a23890-5ad4-38bd-aece-def5940fec89@linux.ibm.com>
Date:   Thu, 9 Aug 2018 11:18:05 -0400
From:   Tony Krowiak <akrowiak@...ux.ibm.com>
To:     Cornelia Huck <cohuck@...hat.com>,
        Tony Krowiak <akrowiak@...ux.vnet.ibm.com>
Cc:     linux-s390@...r.kernel.org, linux-kernel@...r.kernel.org,
        kvm@...r.kernel.org, freude@...ibm.com, schwidefsky@...ibm.com,
        heiko.carstens@...ibm.com, borntraeger@...ibm.com,
        kwankhede@...dia.com, bjsdjshi@...ux.vnet.ibm.com,
        pbonzini@...hat.com, alex.williamson@...hat.com,
        pmorel@...ux.vnet.ibm.com, alifm@...ux.vnet.ibm.com,
        mjrosato@...ux.vnet.ibm.com, jjherne@...ux.vnet.ibm.com,
        thuth@...hat.com, pasic@...ux.vnet.ibm.com, berrange@...hat.com,
        fiuczy@...ux.vnet.ibm.com, buendgen@...ibm.com,
        frankja@...ux.ibm.com
Subject: Re: [PATCH v8 04/22] s390/zcrypt: Integrate ap_asm.h into
 include/asm/ap.h.

On 08/09/2018 05:06 AM, Cornelia Huck wrote:
> On Wed,  8 Aug 2018 10:44:14 -0400
> Tony Krowiak <akrowiak@...ux.vnet.ibm.com> wrote:
>
>> From: Harald Freudenberger <freude@...ibm.com>
>>
>> Move all the inline functions from the ap bus header
>> file ap_asm.h into the in-kernel api header file
>> arch/s390/include/asm/ap.h so that KVM can make use
>> of all the low level AP functions.
>>
>> Signed-off-by: Harald Freudenberger <freude@...ibm.com>
>> Signed-off-by: Christian Borntraeger <borntraeger@...ibm.com>
> You should add your own s-o-b if you are sending on patches written by
> others (even if it does not matter in the end, when they are merged
> through a different path anyway.)

That's rather ironic given I was told in an internal review that I should
not sign off on patches I did not write.

>
>> ---
>>   arch/s390/include/asm/ap.h     |  284 ++++++++++++++++++++++++++++++++++++----
>>   drivers/s390/crypto/ap_asm.h   |  261 ------------------------------------
>>   drivers/s390/crypto/ap_bus.c   |   21 +---
>>   drivers/s390/crypto/ap_bus.h   |    1 +
>>   drivers/s390/crypto/ap_card.c  |    1 -
>>   drivers/s390/crypto/ap_queue.c |    1 -
>>   6 files changed, 259 insertions(+), 310 deletions(-)
>>   delete mode 100644 drivers/s390/crypto/ap_asm.h
>>
>> diff --git a/arch/s390/include/asm/ap.h b/arch/s390/include/asm/ap.h
>> index c1bedb4..046e044 100644
>> --- a/arch/s390/include/asm/ap.h
>> +++ b/arch/s390/include/asm/ap.h
>> @@ -47,6 +47,50 @@ struct ap_queue_status {
>>   };
>>   
>>   /**
>> + * ap_intructions_available() - Test if AP instructions are available.
>> + *
>> + * Returns 0 if the AP instructions are installed.
> Stumbled over this when I was looking at the usage in patch 7: if I see
> a function called '_available' return 0, I'd assume that whatever the
> function tests for is *not* available.
>
> Rather call this function ap_instructions_check_availability() (and
> keep the return code convention), or switch this to return 0 if not
> available and !0 if available?
>
>> + */
>> +static inline int ap_instructions_available(void)
>> +{
>> +	register unsigned long reg0 asm ("0") = AP_MKQID(0, 0);
>> +	register unsigned long reg1 asm ("1") = -ENODEV;
>> +	register unsigned long reg2 asm ("2");
>> +
>> +	asm volatile(
>> +		"   .long 0xb2af0000\n"		/* PQAP(TAPQ) */
>> +		"0: la    %0,0\n"
>> +		"1:\n"
>> +		EX_TABLE(0b, 1b)
>> +		: "+d" (reg1), "=d" (reg2)
>> +		: "d" (reg0)
>> +		: "cc");
>> +	return reg1;
>> +}