From: Andre Przywara <andre.przywara@arm.com>
To: Marc Zyngier <marc.zyngier@arm.com>,
Eric Auger <eric.auger@linaro.org>,
"christoffer.dall@linaro.org" <christoffer.dall@linaro.org>
Cc: Pavel Fedin <p.fedin@samsung.com>,
"kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [PATCH v2 14/15] KVM: arm64: implement MSI injection in ITS emulation
Date: Mon, 24 Aug 2015 15:14:19 +0100 [thread overview]
Message-ID: <55DB26BB.7090703@arm.com> (raw)
In-Reply-To: <55BF9FB0.6070804@arm.com>
Hi,
On 03/08/15 18:06, Marc Zyngier wrote:
> On 03/08/15 16:37, Eric Auger wrote:
>> Andre, Pavel,
>> On 08/03/2015 11:16 AM, Pavel Fedin wrote:
>>> Hello!
>>>
>>>> Again the case that leaves me uncomfortable is the one where the
>>>> userspace does not provide the devid whereas it must (GICv3 ITS case).
>>>
>>> Hypothetical broken userland which does not exist for now ?
>> Yes but that's the rule to be not confident in *any* userspace, isn't it?
Well, that's only regarding safety, not regarding functionality, right?
So if we could break the kernel by not providing the flag and/or devid,
this needs to be fixed. But if it just doesn't work, that's OK.
>>
>> As of now I prefer keeping the flags at uapi level and propagate it
>> downto the kernel, as long as I don't have any answer for the unset
>> devid discrimination question. Please apologize for my stubbornness ;-)
>
> I think this flag should be kept, as it really indicates what is valid
> in the MSI structure. It also has other benefits such as making obvious
> what userspace expects, which can then be checked against the kernel's
> own expectations.
I agree on this. Usually this kind of redundancy leads to strange code,
but this does not seem to apply here, since we can at least still guard
the assignments to demonstrate that the devid field needs to go along
with the flag.
Cheers,
Andre.
WARNING: multiple messages have this Message-ID (diff)
From: andre.przywara@arm.com (Andre Przywara)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 14/15] KVM: arm64: implement MSI injection in ITS emulation
Date: Mon, 24 Aug 2015 15:14:19 +0100 [thread overview]
Message-ID: <55DB26BB.7090703@arm.com> (raw)
In-Reply-To: <55BF9FB0.6070804@arm.com>
Hi,
On 03/08/15 18:06, Marc Zyngier wrote:
> On 03/08/15 16:37, Eric Auger wrote:
>> Andre, Pavel,
>> On 08/03/2015 11:16 AM, Pavel Fedin wrote:
>>> Hello!
>>>
>>>> Again the case that leaves me uncomfortable is the one where the
>>>> userspace does not provide the devid whereas it must (GICv3 ITS case).
>>>
>>> Hypothetical broken userland which does not exist for now ?
>> Yes but that's the rule to be not confident in *any* userspace, isn't it?
Well, that's only regarding safety, not regarding functionality, right?
So if we could break the kernel by not providing the flag and/or devid,
this needs to be fixed. But if it just doesn't work, that's OK.
>>
>> As of now I prefer keeping the flags at uapi level and propagate it
>> downto the kernel, as long as I don't have any answer for the unset
>> devid discrimination question. Please apologize for my stubbornness ;-)
>
> I think this flag should be kept, as it really indicates what is valid
> in the MSI structure. It also has other benefits such as making obvious
> what userspace expects, which can then be checked against the kernel's
> own expectations.
I agree on this. Usually this kind of redundancy leads to strange code,
but this does not seem to apply here, since we can at least still guard
the assignments to demonstrate that the devid field needs to go along
with the flag.
Cheers,
Andre.
next prev parent reply other threads:[~2015-08-24 14:13 UTC|newest]
Thread overview: 138+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-10 14:21 [PATCH v2 00/15] KVM: arm64: GICv3 ITS emulation Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 01/15] KVM: arm/arm64: VGIC: don't track used LRs in the distributor Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-12 9:01 ` Eric Auger
2015-08-12 9:01 ` Eric Auger
2015-08-24 16:33 ` Andre Przywara
2015-08-24 16:33 ` Andre Przywara
2015-08-31 8:42 ` Eric Auger
2015-08-31 8:42 ` Eric Auger
2015-09-02 9:00 ` Andre Przywara
2015-09-02 9:00 ` Andre Przywara
2015-10-02 9:55 ` Pavel Fedin
2015-10-02 9:55 ` Pavel Fedin
2015-10-02 10:32 ` Andre Przywara
2015-10-02 10:32 ` Andre Przywara
2015-10-02 10:39 ` Pavel Fedin
2015-10-02 10:39 ` Pavel Fedin
2015-10-02 12:39 ` Pavel Fedin
2015-10-02 12:39 ` Pavel Fedin
2015-10-02 12:49 ` Andre Przywara
2015-10-02 12:49 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 02/15] KVM: extend struct kvm_msi to hold a 32-bit device ID Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 03/15] KVM: arm/arm64: add emulation model specific destroy function Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 04/15] KVM: arm/arm64: extend arch CAP checks to allow per-VM capabilities Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-12 12:26 ` Eric Auger
2015-08-12 12:26 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 05/15] KVM: arm/arm64: make GIC frame address initialization model specific Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-12 13:02 ` Eric Auger
2015-08-12 13:02 ` Eric Auger
2015-08-24 17:24 ` Andre Przywara
2015-08-24 17:24 ` Andre Przywara
2015-08-31 9:31 ` Eric Auger
2015-08-31 9:31 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 06/15] KVM: arm64: Introduce new MMIO region for the ITS base address Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-13 12:17 ` Eric Auger
2015-08-13 12:17 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 07/15] KVM: arm64: handle ITS related GICv3 redistributor registers Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-13 12:17 ` Eric Auger
2015-08-13 12:17 ` Eric Auger
2015-08-24 18:08 ` Andre Przywara
2015-08-24 18:08 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 08/15] KVM: arm64: introduce ITS emulation file with stub functions Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-13 12:48 ` Eric Auger
2015-08-13 12:48 ` Eric Auger
2015-08-25 9:39 ` Andre Przywara
2015-08-25 9:39 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 09/15] KVM: arm64: implement basic ITS register handlers Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-13 15:25 ` Eric Auger
2015-08-13 15:25 ` Eric Auger
2015-08-25 10:23 ` Andre Przywara
2015-08-25 10:23 ` Andre Przywara
2015-10-02 7:51 ` Pavel Fedin
2015-10-02 7:51 ` Pavel Fedin
2015-07-10 14:21 ` [PATCH v2 10/15] KVM: arm64: add data structures to model ITS interrupt translation Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-13 15:46 ` Eric Auger
2015-08-13 15:46 ` Eric Auger
2015-08-25 11:15 ` Andre Przywara
2015-08-25 11:15 ` Andre Przywara
2015-08-27 14:16 ` Eric Auger
2015-08-27 14:16 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 11/15] KVM: arm64: handle pending bit for LPIs in ITS emulation Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-14 11:58 ` Eric Auger
2015-08-14 11:58 ` Eric Auger
2015-08-25 14:34 ` Andre Przywara
2015-08-25 14:34 ` Andre Przywara
2015-08-31 9:45 ` Eric Auger
2015-08-31 9:45 ` Eric Auger
2015-10-07 8:39 ` Pavel Fedin
2015-10-07 8:39 ` Pavel Fedin
2015-10-07 19:53 ` Christoffer Dall
2015-10-07 19:53 ` Christoffer Dall
2015-07-10 14:21 ` [PATCH v2 12/15] KVM: arm64: sync LPI configuration and pending tables Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-14 11:58 ` Eric Auger
2015-08-14 11:58 ` Eric Auger
2015-08-14 12:35 ` Eric Auger
2015-08-14 12:35 ` Eric Auger
2015-08-25 15:47 ` Andre Przywara
2015-08-25 15:47 ` Andre Przywara
2015-08-31 9:51 ` Eric Auger
2015-08-31 9:51 ` Eric Auger
2015-08-25 15:27 ` Andre Przywara
2015-08-25 15:27 ` Andre Przywara
2015-08-31 9:47 ` Eric Auger
2015-08-31 9:47 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 13/15] KVM: arm64: implement ITS command queue command handlers Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-08-17 13:33 ` Eric Auger
2015-08-17 13:33 ` Eric Auger
2015-10-07 14:54 ` Andre Przywara
2015-10-07 14:54 ` Andre Przywara
2015-07-10 14:21 ` [PATCH v2 14/15] KVM: arm64: implement MSI injection in ITS emulation Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-07-31 13:22 ` Eric Auger
2015-07-31 13:22 ` Eric Auger
2015-08-02 20:20 ` Andre Przywara
2015-08-02 20:20 ` Andre Przywara
2015-08-03 6:41 ` Pavel Fedin
2015-08-03 6:41 ` Pavel Fedin
2015-08-03 9:07 ` Eric Auger
2015-08-03 9:07 ` Eric Auger
2015-08-03 9:16 ` Pavel Fedin
2015-08-03 9:16 ` Pavel Fedin
2015-08-03 15:37 ` Eric Auger
2015-08-03 15:37 ` Eric Auger
2015-08-03 17:06 ` Marc Zyngier
2015-08-03 17:06 ` Marc Zyngier
2015-08-04 6:53 ` Pavel Fedin
2015-08-04 6:53 ` Pavel Fedin
2015-08-24 14:14 ` Andre Przywara [this message]
2015-08-24 14:14 ` Andre Przywara
2015-08-17 13:44 ` Eric Auger
2015-08-17 13:44 ` Eric Auger
2015-07-10 14:21 ` [PATCH v2 15/15] KVM: arm64: enable ITS emulation as a virtual MSI controller Andre Przywara
2015-07-10 14:21 ` Andre Przywara
2015-07-15 9:10 ` Pavel Fedin
2015-07-15 9:10 ` Pavel Fedin
2015-07-15 9:52 ` Andre Przywara
2015-07-15 9:52 ` Andre Przywara
2015-07-15 10:01 ` Pavel Fedin
2015-07-15 10:01 ` Pavel Fedin
2015-07-15 12:02 ` [PATCH v2 00/15] KVM: arm64: GICv3 ITS emulation Pavel Fedin
2015-07-15 12:02 ` Pavel Fedin
2015-09-24 11:18 ` Pavel Fedin
2015-09-24 11:18 ` Pavel Fedin
2015-09-24 11:35 ` Andre Przywara
2015-09-24 11:35 ` Andre Przywara
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