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From: Christoffer Dall <christoffer.dall@linaro.org>
To: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	kvmarm@lists.cs.columbia.edu
Subject: Re: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs shared between EL1 and EL2
Date: Tue, 2 Feb 2016 16:46:45 +0100	[thread overview]
Message-ID: <20160202154645.GE6190@cbox> (raw)
In-Reply-To: <56B07ADD.60300@arm.com>

On Tue, Feb 02, 2016 at 09:46:05AM +0000, Marc Zyngier wrote:
> On 01/02/16 13:54, Christoffer Dall wrote:
> > On Mon, Jan 25, 2016 at 03:53:44PM +0000, Marc Zyngier wrote:
> >> A handful of system registers are still shared between EL1 and EL2,
> >> even while using VHE. These are tpidr*_el[01], actlr_el1, sp0, elr,
> >> and spsr.
> > 
> > So by shared registers you mean registers that do both have an EL0/1
> > version as well as an EL2 version, but where accesses aren't rewritten
> > transparently?
> 
> No, I mean that these registers do *not* have a separate banked version.
> There is only a single set of registers, which have to be save/restored
> the old way.

huh, ARMv8 clearly specifies the existence of TPIDR_EL0, TPIDR_EL1, and
TPIDR_EL2, for example.

I cannot seem to find anywhere in the VHE spec that says that the
TPIDR_EL2 goes away.  I'm confused now.

> 
> > 
> > also, by sp0 do you mean sp_el0, and by elr you mean elr_el1, and by
> > spsr you mean spsr_el1 ?
> 
> sp0 -> sp_el0 indeed. elr and spsr really are the guest PC and PSTATE,
> so I should really reword this commit message, it is utterly confusing.
> 
I guess I don't understand the definition of a 'shared' register given
your comments here...

Thanks,
-Christoffer

WARNING: multiple messages have this Message-ID (diff)
From: christoffer.dall@linaro.org (Christoffer Dall)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs shared between EL1 and EL2
Date: Tue, 2 Feb 2016 16:46:45 +0100	[thread overview]
Message-ID: <20160202154645.GE6190@cbox> (raw)
In-Reply-To: <56B07ADD.60300@arm.com>

On Tue, Feb 02, 2016 at 09:46:05AM +0000, Marc Zyngier wrote:
> On 01/02/16 13:54, Christoffer Dall wrote:
> > On Mon, Jan 25, 2016 at 03:53:44PM +0000, Marc Zyngier wrote:
> >> A handful of system registers are still shared between EL1 and EL2,
> >> even while using VHE. These are tpidr*_el[01], actlr_el1, sp0, elr,
> >> and spsr.
> > 
> > So by shared registers you mean registers that do both have an EL0/1
> > version as well as an EL2 version, but where accesses aren't rewritten
> > transparently?
> 
> No, I mean that these registers do *not* have a separate banked version.
> There is only a single set of registers, which have to be save/restored
> the old way.

huh, ARMv8 clearly specifies the existence of TPIDR_EL0, TPIDR_EL1, and
TPIDR_EL2, for example.

I cannot seem to find anywhere in the VHE spec that says that the
TPIDR_EL2 goes away.  I'm confused now.

> 
> > 
> > also, by sp0 do you mean sp_el0, and by elr you mean elr_el1, and by
> > spsr you mean spsr_el1 ?
> 
> sp0 -> sp_el0 indeed. elr and spsr really are the guest PC and PSTATE,
> so I should really reword this commit message, it is utterly confusing.
> 
I guess I don't understand the definition of a 'shared' register given
your comments here...

Thanks,
-Christoffer

  reply	other threads:[~2016-02-02 15:46 UTC|newest]

Thread overview: 231+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-25 15:53 [PATCH v2 00/21] arm64: Virtualization Host Extension support Marc Zyngier
2016-01-25 15:53 ` Marc Zyngier
2016-01-25 15:53 ` Marc Zyngier
2016-01-25 15:53 ` [PATCH v2 01/21] arm/arm64: Add new is_kernel_in_hyp_mode predicate Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:59   ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 02/21] arm64: Allow the arch timer to use the HYP timer Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 12:29   ` Christoffer Dall
2016-02-01 12:29     ` Christoffer Dall
2016-02-01 12:29     ` Christoffer Dall
2016-02-01 13:42     ` Marc Zyngier
2016-02-01 13:42       ` Marc Zyngier
2016-02-01 13:42       ` Marc Zyngier
2016-02-01 15:37       ` Christoffer Dall
2016-02-01 15:37         ` Christoffer Dall
2016-02-01 15:37         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 03/21] arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:59   ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 04/21] arm64: KVM: Skip HYP setup when already running in HYP Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:59   ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 05/21] arm64: KVM: VHE: Turn VTCR_EL2 setup into a reusable macro Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:13   ` Christoffer Dall
2016-02-01 13:13     ` Christoffer Dall
2016-02-01 13:13     ` Christoffer Dall
2016-02-01 14:21     ` Marc Zyngier
2016-02-01 14:21       ` Marc Zyngier
2016-02-01 14:21       ` Marc Zyngier
2016-02-01 15:38       ` Christoffer Dall
2016-02-01 15:38         ` Christoffer Dall
2016-02-01 15:38         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 06/21] arm64: KVM: VHE: Patch out use of HVC Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:16   ` Christoffer Dall
2016-02-01 13:16     ` Christoffer Dall
2016-02-01 13:34     ` Marc Zyngier
2016-02-01 13:34       ` Marc Zyngier
2016-02-01 15:36       ` Catalin Marinas
2016-02-01 15:36         ` Catalin Marinas
2016-02-01 15:36         ` Catalin Marinas
2016-02-01 16:20         ` Marc Zyngier
2016-02-01 16:20           ` Marc Zyngier
2016-02-01 16:20           ` Marc Zyngier
2016-02-01 17:08           ` Ard Biesheuvel
2016-02-01 17:08             ` Ard Biesheuvel
2016-02-01 17:08             ` Ard Biesheuvel
2016-02-01 17:28             ` Marc Zyngier
2016-02-01 17:28               ` Marc Zyngier
2016-02-01 17:28               ` Marc Zyngier
2016-02-02 15:42               ` Christoffer Dall
2016-02-02 15:42                 ` Christoffer Dall
2016-02-01 15:39       ` Christoffer Dall
2016-02-01 15:39         ` Christoffer Dall
2016-02-01 15:39         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 07/21] arm64: KVM: VHE: Patch out kern_hyp_va Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:20   ` Christoffer Dall
2016-02-01 13:20     ` Christoffer Dall
2016-02-01 13:20     ` Christoffer Dall
2016-02-01 13:38     ` Marc Zyngier
2016-02-01 13:38       ` Marc Zyngier
2016-02-01 13:38       ` Marc Zyngier
2016-02-01 15:40       ` Christoffer Dall
2016-02-01 15:40         ` Christoffer Dall
2016-02-01 15:40         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 08/21] arm64: KVM: VHE: Introduce unified system register accessors Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:47   ` Christoffer Dall
2016-02-01 13:47     ` Christoffer Dall
2016-02-01 13:47     ` Christoffer Dall
2016-02-01 14:04     ` Marc Zyngier
2016-02-01 14:04       ` Marc Zyngier
2016-02-01 14:04       ` Marc Zyngier
2016-02-01 15:43       ` Christoffer Dall
2016-02-01 15:43         ` Christoffer Dall
2016-02-01 15:43         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 09/21] arm64: KVM: VHE: Differenciate host/guest sysreg save/restore Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:59   ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 10/21] arm64: KVM: VHE: Split save/restore of sysregs shared between EL1 and EL2 Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:54   ` Christoffer Dall
2016-02-01 13:54     ` Christoffer Dall
2016-02-01 13:54     ` Christoffer Dall
2016-02-02  9:46     ` Marc Zyngier
2016-02-02  9:46       ` Marc Zyngier
2016-02-02  9:46       ` Marc Zyngier
2016-02-02 15:46       ` Christoffer Dall [this message]
2016-02-02 15:46         ` Christoffer Dall
2016-02-02 16:19         ` Marc Zyngier
2016-02-02 16:19           ` Marc Zyngier
2016-02-02 16:19           ` Marc Zyngier
2016-02-02 20:07           ` Christoffer Dall
2016-02-02 20:07             ` Christoffer Dall
2016-02-02 20:07             ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 11/21] arm64: KVM: VHE: Use unified system register accessors Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 13:59   ` Christoffer Dall
2016-02-01 13:59     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 12/21] arm64: KVM: VHE: Enable minimal sysreg save/restore Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:02   ` Christoffer Dall
2016-02-01 14:02     ` Christoffer Dall
2016-02-01 14:02     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 13/21] arm64: KVM: VHE: Make __fpsimd_enabled VHE aware Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:17   ` Christoffer Dall
2016-02-01 14:17     ` Christoffer Dall
2016-02-01 14:17     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 14/21] arm64: KVM: VHE: Implement VHE activate/deactivate_traps Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:20   ` Christoffer Dall
2016-02-01 14:20     ` Christoffer Dall
2016-02-01 14:20     ` Christoffer Dall
2016-02-02 11:27     ` Marc Zyngier
2016-02-02 11:27       ` Marc Zyngier
2016-01-25 15:53 ` [PATCH v2 15/21] arm64: KVM: VHE: Use unified sysreg accessors for timer Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:23   ` Christoffer Dall
2016-02-01 14:23     ` Christoffer Dall
2016-02-01 14:23     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 16/21] arm64: KVM: VHE: Add fpsimd enabling on guest access Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:24   ` Christoffer Dall
2016-02-01 14:24     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 17/21] arm64: KVM: VHE: Add alternative panic handling Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:26   ` Christoffer Dall
2016-02-01 14:26     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 18/21] arm64: KVM: Introduce hyp_alternate_value helper Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 14:41   ` Christoffer Dall
2016-02-01 14:41     ` Christoffer Dall
2016-02-02 13:42     ` Marc Zyngier
2016-02-02 13:42       ` Marc Zyngier
2016-02-02 15:47       ` Christoffer Dall
2016-02-02 15:47         ` Christoffer Dall
2016-02-02 15:47         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 19/21] arm64: KVM: Move most of the fault decoding to C Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-02-01 15:21   ` Christoffer Dall
2016-02-01 15:21     ` Christoffer Dall
2016-02-01 15:21     ` Christoffer Dall
2016-02-02 14:24     ` Marc Zyngier
2016-02-02 14:24       ` Marc Zyngier
2016-02-02 14:24       ` Marc Zyngier
2016-02-02 15:50       ` Christoffer Dall
2016-02-02 15:50         ` Christoffer Dall
2016-02-02 15:50         ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 20/21] arm64: VHE: Add support for running Linux in EL2 mode Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-26 14:04   ` Suzuki K. Poulose
2016-01-26 14:04     ` Suzuki K. Poulose
2016-01-26 14:30     ` Suzuki K. Poulose
2016-01-26 14:30       ` Suzuki K. Poulose
2016-02-01 15:26   ` Christoffer Dall
2016-02-01 15:26     ` Christoffer Dall
2016-01-25 15:53 ` [PATCH v2 21/21] arm64: Panic when VHE and non VHE CPUs coexist Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-25 15:53   ` Marc Zyngier
2016-01-26 14:25   ` Suzuki K. Poulose
2016-01-26 14:25     ` Suzuki K. Poulose
2016-01-26 14:25     ` Suzuki K. Poulose
2016-01-26 14:34     ` Marc Zyngier
2016-01-26 14:34       ` Marc Zyngier
2016-01-26 14:34       ` Marc Zyngier
2016-02-01 15:36   ` Christoffer Dall
2016-02-01 15:36     ` Christoffer Dall
2016-02-01 15:36     ` Christoffer Dall
2016-02-02 15:32     ` Marc Zyngier
2016-02-02 15:32       ` Marc Zyngier
2016-02-03  8:49       ` Christoffer Dall
2016-02-03  8:49         ` Christoffer Dall
2016-02-03  8:49         ` Christoffer Dall
2016-02-03 17:45         ` Marc Zyngier
2016-02-03 17:45           ` Marc Zyngier
2016-02-03 17:45           ` Marc Zyngier
2016-02-03 19:12           ` Christoffer Dall
2016-02-03 19:12             ` Christoffer Dall
2016-02-03 19:12             ` Christoffer Dall
2016-01-25 16:15 ` [PATCH v2 00/21] arm64: Virtualization Host Extension support Arnd Bergmann
2016-01-25 16:15   ` Arnd Bergmann
2016-01-25 16:15   ` Arnd Bergmann
2016-01-25 16:23   ` Marc Zyngier
2016-01-25 16:23     ` Marc Zyngier
2016-01-25 16:26     ` Arnd Bergmann
2016-01-25 16:26       ` Arnd Bergmann
2016-01-25 16:26       ` Arnd Bergmann
2016-01-25 16:26 ` Will Deacon
2016-01-25 16:26   ` Will Deacon
2016-01-25 16:26   ` Will Deacon
2016-01-25 16:37   ` Marc Zyngier
2016-01-25 16:37     ` Marc Zyngier
2016-01-25 16:37     ` Marc Zyngier
2016-01-25 16:44     ` Will Deacon
2016-01-25 16:44       ` Will Deacon
2016-01-25 19:16       ` Marc Zyngier
2016-01-25 19:16         ` Marc Zyngier
2016-01-25 19:16         ` Marc Zyngier
2016-02-01 16:25 ` Christoffer Dall
2016-02-01 16:25   ` Christoffer Dall
2016-02-01 16:25   ` Christoffer Dall

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