From: Suzuki K Poulose <suzuki.poulose@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
Steven Price <steven.price@arm.com>
Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev,
Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
James Morse <james.morse@arm.com>,
Oliver Upton <oliver.upton@linux.dev>,
Zenghui Yu <yuzenghui@huawei.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, Joey Gouly <joey.gouly@arm.com>,
Alexandru Elisei <alexandru.elisei@arm.com>,
Christoffer Dall <christoffer.dall@arm.com>,
Fuad Tabba <tabba@google.com>,
linux-coco@lists.linux.dev,
Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Subject: Re: [PATCH v2 10/14] arm64: Force device mappings to be non-secure shared
Date: Wed, 15 May 2024 12:00:49 +0100 [thread overview]
Message-ID: <4e89f047-ae70-43a8-a459-e375ca05b2c2@arm.com> (raw)
In-Reply-To: <ZkR535Hmh3WkMYai@arm.com>
On 15/05/2024 10:01, Catalin Marinas wrote:
> On Fri, Apr 12, 2024 at 09:42:09AM +0100, Steven Price wrote:
>> From: Suzuki K Poulose <suzuki.poulose@arm.com>
>>
>> Device mappings (currently) need to be emulated by the VMM so must be
>> mapped shared with the host.
>
> You say "currently". What's the plan when the device is not emulated?
> How would the guest distinguish what's emulated and what's not to avoid
> setting the PROT_NS_SHARED bit?
Arm CCA plans to add support for passing through real devices,
which support PCI-TDISP protocol. This would involve the Realm
authenticating the device and explicitly requesting "protected"
mapping *after* the verification (with the help of RMM).
>
>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> Signed-off-by: Steven Price <steven.price@arm.com>
>> ---
>> arch/arm64/include/asm/pgtable.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
>> index f5376bd567a1..db71c564ec21 100644
>> --- a/arch/arm64/include/asm/pgtable.h
>> +++ b/arch/arm64/include/asm/pgtable.h
>> @@ -598,7 +598,7 @@ static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
>> #define pgprot_writecombine(prot) \
>> __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
>> #define pgprot_device(prot) \
>> - __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
>> + __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN | PROT_NS_SHARED)
>
> This pgprot_device() is not the only one used to map device resources.
> pgprot_writecombine() is another commonly macro. It feels like a hack to
> plug one but not the other and without any way for the guest to figure
> out what's emulated.
Agree. I have been exploring hooking this into ioremap_prot() where we
could apply the attribute accordingly. We will change it in the next
version.
>
> Can the DT actually place those emulated ranges in the higher IPA space
> so that we avoid randomly adding this attribute for devices?
It can, but then we kind of break the "Realm" view of the IPA space.
i.e., right now it only knows about the "lower IPA" half and uses the
top bit as a protection attr to access the IPA as shared.
Expanding IPA size view kind of breaks "sharing memory", where, we
must "use a different PA" for a page that is now shared.
Suzuki
next prev parent reply other threads:[~2024-05-15 11:00 UTC|newest]
Thread overview: 134+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-12 8:40 [v2] Support for Arm CCA VMs on Linux Steven Price
2024-04-11 18:54 ` Itaru Kitayama
2024-04-15 8:14 ` Steven Price
2024-04-12 8:41 ` [PATCH v2 00/14] arm64: Support for running as a guest in Arm CCA Steven Price
2024-04-12 8:42 ` [PATCH v2 01/14] arm64: rsi: Add RSI definitions Steven Price
2024-04-12 8:42 ` [PATCH v2 02/14] arm64: Detect if in a realm and set RIPAS RAM Steven Price
2024-05-10 17:35 ` Catalin Marinas
2024-05-14 10:18 ` Suzuki K Poulose
2024-05-16 14:32 ` Catalin Marinas
2024-05-15 15:03 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 03/14] arm64: realm: Query IPA size from the RMM Steven Price
2024-05-13 14:03 ` Catalin Marinas
2024-05-16 15:13 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 04/14] arm64: Mark all I/O as non-secure shared Steven Price
2024-04-12 8:42 ` [PATCH v2 05/14] fixmap: Allow architecture overriding set_fixmap_io Steven Price
2024-04-12 8:42 ` [PATCH v2 06/14] arm64: Override set_fixmap_io Steven Price
2024-05-13 16:14 ` Catalin Marinas
2024-05-14 10:21 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 07/14] arm64: Make the PHYS_MASK_SHIFT dynamic Steven Price
2024-05-13 16:38 ` Catalin Marinas
2024-05-16 15:34 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 08/14] arm64: Enforce bounce buffers for realm DMA Steven Price
2024-05-13 16:56 ` Catalin Marinas
2024-04-12 8:42 ` [PATCH v2 09/14] arm64: Enable memory encrypt for Realms Steven Price
2024-04-15 3:13 ` kernel test robot
2024-04-25 13:42 ` Suzuki K Poulose
2024-04-25 15:52 ` Steven Price
2024-04-25 16:29 ` Suzuki K Poulose
2024-04-25 18:16 ` Emanuele Rocca
2024-05-14 18:00 ` Catalin Marinas
2024-05-15 10:47 ` Suzuki K Poulose
2024-05-16 7:48 ` Catalin Marinas
2024-05-16 9:06 ` Suzuki K Poulose
2024-05-20 16:53 ` Catalin Marinas
2024-05-20 20:32 ` Michael Kelley
2024-05-21 10:14 ` Catalin Marinas
2024-05-21 15:58 ` Michael Kelley
2024-04-12 8:42 ` [PATCH v2 10/14] arm64: Force device mappings to be non-secure shared Steven Price
2024-05-15 9:01 ` Catalin Marinas
2024-05-15 11:00 ` Suzuki K Poulose [this message]
2024-05-17 9:34 ` Catalin Marinas
2024-04-12 8:42 ` [PATCH v2 11/14] efi: arm64: Map Device with Prot Shared Steven Price
2024-04-12 8:42 ` [PATCH v2 12/14] arm64: realm: Support nonsecure ITS emulation shared Steven Price
2024-05-15 11:01 ` Catalin Marinas
2024-05-22 15:52 ` Steven Price
2024-05-22 17:05 ` Catalin Marinas
2024-05-23 9:57 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 13/14] arm64: rsi: Interfaces to query attestation token Steven Price
2024-05-15 11:10 ` Catalin Marinas
2024-05-22 15:52 ` Steven Price
2024-05-31 16:29 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 14/14] virt: arm-cca-guest: TSM_REPORT support for realms Steven Price
2024-04-24 13:06 ` Thomas Fossati
2024-04-24 13:27 ` Suzuki K Poulose
2024-04-24 13:19 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 00/43] arm64: Support for Arm CCA in KVM Steven Price
2024-04-12 8:42 ` [PATCH v2 01/43] KVM: Prepare for handling only shared mappings in mmu_notifier events Steven Price
2024-04-25 9:48 ` Fuad Tabba
2024-04-25 15:58 ` Steven Price
2024-04-25 22:56 ` Sean Christopherson
2024-04-12 8:42 ` [PATCH v2 02/43] kvm: arm64: pgtable: Track the number of pages in the entry level Steven Price
2024-04-12 8:42 ` [PATCH v2 03/43] kvm: arm64: Include kvm_emulate.h in kvm/arm_psci.h Steven Price
2024-04-12 8:42 ` [PATCH v2 04/43] arm64: RME: Handle Granule Protection Faults (GPFs) Steven Price
2024-04-16 11:17 ` Suzuki K Poulose
2024-04-18 13:17 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 05/43] arm64: RME: Add SMC definitions for calling the RMM Steven Price
2024-04-16 12:38 ` Suzuki K Poulose
2024-04-18 13:17 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 06/43] arm64: RME: Add wrappers for RMI calls Steven Price
2024-04-16 13:14 ` Suzuki K Poulose
2024-04-19 11:18 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 07/43] arm64: RME: Check for RME support at KVM init Steven Price
2024-04-16 13:30 ` Suzuki K Poulose
2024-04-22 15:39 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 08/43] arm64: RME: Define the user ABI Steven Price
2024-04-12 8:42 ` [PATCH v2 09/43] arm64: RME: ioctls to create and configure realms Steven Price
2024-04-17 9:51 ` Suzuki K Poulose
2024-04-22 16:33 ` Steven Price
2024-04-18 16:04 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 10/43] kvm: arm64: Expose debug HW register numbers for Realm Steven Price
2024-04-12 8:42 ` [PATCH v2 11/43] arm64: kvm: Allow passing machine type in KVM creation Steven Price
2024-04-17 10:20 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 12/43] arm64: RME: Keep a spare page delegated to the RMM Steven Price
2024-04-17 10:19 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 13/43] arm64: RME: RTT handling Steven Price
2024-04-17 13:37 ` Suzuki K Poulose
2024-04-24 10:59 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 14/43] arm64: RME: Allocate/free RECs to match vCPUs Steven Price
2024-04-18 9:23 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 15/43] arm64: RME: Support for the VGIC in realms Steven Price
2024-04-12 8:42 ` [PATCH v2 16/43] KVM: arm64: Support timers in realm RECs Steven Price
2024-04-18 9:30 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 17/43] arm64: RME: Allow VMM to set RIPAS Steven Price
2024-04-19 9:34 ` Suzuki K Poulose
2024-04-19 10:20 ` Suzuki K Poulose
2024-05-01 15:47 ` Steven Price
2024-05-02 10:16 ` Suzuki K Poulose
2024-04-25 9:53 ` Fuad Tabba
2024-05-01 14:27 ` Jean-Philippe Brucker
2024-05-01 14:56 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 18/43] arm64: RME: Handle realm enter/exit Steven Price
2024-04-19 13:00 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 19/43] KVM: arm64: Handle realm MMIO emulation Steven Price
2024-04-12 8:42 ` [PATCH v2 20/43] arm64: RME: Allow populating initial contents Steven Price
2024-04-19 13:17 ` Suzuki K Poulose
2024-04-12 8:42 ` [PATCH v2 21/43] arm64: RME: Runtime faulting of memory Steven Price
2024-04-25 10:43 ` Fuad Tabba
2024-05-31 16:03 ` Steven Price
2024-04-12 8:42 ` [PATCH v2 22/43] KVM: arm64: Handle realm VCPU load Steven Price
2024-04-12 8:42 ` [PATCH v2 23/43] KVM: arm64: Validate register access for a Realm VM Steven Price
2024-04-12 8:42 ` [PATCH v2 24/43] KVM: arm64: Handle Realm PSCI requests Steven Price
2024-04-12 8:42 ` [PATCH v2 25/43] KVM: arm64: WARN on injected undef exceptions Steven Price
2024-04-12 8:42 ` [PATCH v2 26/43] arm64: Don't expose stolen time for realm guests Steven Price
2024-04-12 8:42 ` [PATCH v2 27/43] arm64: rme: allow userspace to inject aborts Steven Price
2024-04-12 8:42 ` [PATCH v2 28/43] arm64: rme: support RSI_HOST_CALL Steven Price
2024-04-12 8:42 ` [PATCH v2 29/43] arm64: rme: Allow checking SVE on VM instance Steven Price
2024-04-12 8:42 ` [PATCH v2 30/43] arm64: RME: Always use 4k pages for realms Steven Price
2024-04-12 8:42 ` [PATCH v2 31/43] arm64: rme: Prevent Device mappings for Realms Steven Price
2024-04-12 8:42 ` [PATCH v2 32/43] arm_pmu: Provide a mechanism for disabling the physical IRQ Steven Price
2024-04-12 8:42 ` [PATCH v2 33/43] arm64: rme: Enable PMU support with a realm guest Steven Price
2024-04-13 23:44 ` kernel test robot
2024-04-18 16:06 ` Suzuki K Poulose
2024-04-12 8:43 ` [PATCH v2 34/43] kvm: rme: Hide KVM_CAP_READONLY_MEM for realm guests Steven Price
2024-04-12 8:43 ` [PATCH v2 35/43] arm64: RME: Propagate number of breakpoints and watchpoints to userspace Steven Price
2024-04-12 8:43 ` [PATCH v2 36/43] arm64: RME: Set breakpoint parameters through SET_ONE_REG Steven Price
2024-04-12 8:43 ` [PATCH v2 37/43] arm64: RME: Initialize PMCR.N with number counter supported by RMM Steven Price
2024-04-12 8:43 ` [PATCH v2 38/43] arm64: RME: Propagate max SVE vector length from RMM Steven Price
2024-04-12 8:43 ` [PATCH v2 39/43] arm64: RME: Configure max SVE vector length for a Realm Steven Price
2024-04-12 8:43 ` [PATCH v2 40/43] arm64: RME: Provide register list for unfinalized RME RECs Steven Price
2024-04-12 8:43 ` [PATCH v2 41/43] arm64: RME: Provide accurate register list Steven Price
2024-04-12 8:43 ` [PATCH v2 42/43] arm64: kvm: Expose support for private memory Steven Price
2024-04-25 14:44 ` Fuad Tabba
2024-04-12 8:43 ` [PATCH v2 43/43] KVM: arm64: Allow activating realms Steven Price
2024-04-12 16:52 ` [v2] Support for Arm CCA VMs on Linux Jean-Philippe Brucker
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