From: Catalin Marinas <catalin.marinas@arm.com>
To: Guo Ren <guoren@kernel.org>
Cc: Julien Grall <julien.grall@arm.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, aou@eecs.berkeley.edu,
gary@garyguo.net, Atish Patra <Atish.Patra@wdc.com>,
hch@infradead.org, paul.walmsley@sifive.com, rppt@linux.ibm.com,
linux-riscv@lists.infradead.org, Anup Patel <anup.Patel@wdc.com>,
Palmer Dabbelt <palmer@sifive.com>,
suzuki.poulose@arm.com, Marc Zyngier <marc.zyngier@arm.com>,
julien.thierry@arm.com, Will Deacon <will.deacon@arm.com>,
christoffer.dall@arm.com, james.morse@arm.com,
linux-csky@vger.kernel.org
Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file
Date: Mon, 22 Jul 2019 17:38:12 +0100 [thread overview]
Message-ID: <20190722163811.GJ60625@arrakis.emea.arm.com> (raw)
In-Reply-To: <CAJF2gTTEbhA-pZCPGuUNqXT9F-vk8fSTyNJyEOpn=QE=toAN3g@mail.gmail.com>
On Tue, Jul 16, 2019 at 11:31:27AM +0800, Guo Ren wrote:
> I saw arm64 to prevent speculation by temporarily setting TTBR0.el1 to
> a zero page table. Is that used to prevent speculative execution user
> space code or just prevent ld/st in copy_use_* ?
Only to prevent explicit ld/st from user. On ARMv8.1+, we don't normally
use the TTBR0 trick but rather disable user space access using the PAN
(privileged access never) feature. However, I don't think PAN disables
speculative accesses, only explicit loads/stores. Also, with ARMv8.2
Linux uses the LDTR/STTR instructions in copy_*_user() which don't need
to disable PAN explicitly.
--
Catalin
WARNING: multiple messages have this Message-ID (diff)
From: Catalin Marinas <catalin.marinas@arm.com>
To: Guo Ren <guoren@kernel.org>
Cc: julien.thierry@arm.com, aou@eecs.berkeley.edu,
james.morse@arm.com, suzuki.poulose@arm.com,
Marc Zyngier <marc.zyngier@arm.com>,
Anup Patel <anup.Patel@wdc.com>,
Will Deacon <will.deacon@arm.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-csky@vger.kernel.org, rppt@linux.ibm.com,
hch@infradead.org, Atish Patra <Atish.Patra@wdc.com>,
Julien Grall <julien.grall@arm.com>,
Palmer Dabbelt <palmer@sifive.com>,
gary@garyguo.net, paul.walmsley@sifive.com,
christoffer.dall@arm.com, linux-riscv@lists.infradead.org,
kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file
Date: Mon, 22 Jul 2019 17:38:12 +0100 [thread overview]
Message-ID: <20190722163811.GJ60625@arrakis.emea.arm.com> (raw)
In-Reply-To: <CAJF2gTTEbhA-pZCPGuUNqXT9F-vk8fSTyNJyEOpn=QE=toAN3g@mail.gmail.com>
On Tue, Jul 16, 2019 at 11:31:27AM +0800, Guo Ren wrote:
> I saw arm64 to prevent speculation by temporarily setting TTBR0.el1 to
> a zero page table. Is that used to prevent speculative execution user
> space code or just prevent ld/st in copy_use_* ?
Only to prevent explicit ld/st from user. On ARMv8.1+, we don't normally
use the TTBR0 trick but rather disable user space access using the PAN
(privileged access never) feature. However, I don't think PAN disables
speculative accesses, only explicit loads/stores. Also, with ARMv8.2
Linux uses the LDTR/STTR instructions in copy_*_user() which don't need
to disable PAN explicitly.
--
Catalin
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
WARNING: multiple messages have this Message-ID (diff)
From: Catalin Marinas <catalin.marinas@arm.com>
To: Guo Ren <guoren@kernel.org>
Cc: aou@eecs.berkeley.edu, Marc Zyngier <marc.zyngier@arm.com>,
Anup Patel <anup.Patel@wdc.com>,
Will Deacon <will.deacon@arm.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-csky@vger.kernel.org, rppt@linux.ibm.com,
hch@infradead.org, Atish Patra <Atish.Patra@wdc.com>,
Julien Grall <julien.grall@arm.com>,
Palmer Dabbelt <palmer@sifive.com>,
gary@garyguo.net, paul.walmsley@sifive.com,
linux-riscv@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file
Date: Mon, 22 Jul 2019 17:38:12 +0100 [thread overview]
Message-ID: <20190722163811.GJ60625@arrakis.emea.arm.com> (raw)
In-Reply-To: <CAJF2gTTEbhA-pZCPGuUNqXT9F-vk8fSTyNJyEOpn=QE=toAN3g@mail.gmail.com>
On Tue, Jul 16, 2019 at 11:31:27AM +0800, Guo Ren wrote:
> I saw arm64 to prevent speculation by temporarily setting TTBR0.el1 to
> a zero page table. Is that used to prevent speculative execution user
> space code or just prevent ld/st in copy_use_* ?
Only to prevent explicit ld/st from user. On ARMv8.1+, we don't normally
use the TTBR0 trick but rather disable user space access using the PAN
(privileged access never) feature. However, I don't think PAN disables
speculative accesses, only explicit loads/stores. Also, with ARMv8.2
Linux uses the LDTR/STTR instructions in copy_*_user() which don't need
to disable PAN explicitly.
--
Catalin
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
WARNING: multiple messages have this Message-ID (diff)
From: Catalin Marinas <catalin.marinas@arm.com>
To: Guo Ren <guoren@kernel.org>
Cc: julien.thierry@arm.com, aou@eecs.berkeley.edu,
james.morse@arm.com, suzuki.poulose@arm.com,
Marc Zyngier <marc.zyngier@arm.com>,
Anup Patel <anup.Patel@wdc.com>,
Will Deacon <will.deacon@arm.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-csky@vger.kernel.org, rppt@linux.ibm.com,
hch@infradead.org, Atish Patra <Atish.Patra@wdc.com>,
Julien Grall <julien.grall@arm.com>,
Palmer Dabbelt <palmer@sifive.com>,
gary@garyguo.net, paul.walmsley@sifive.com,
christoffer.dall@arm.com, linux-riscv@lists.infradead.org,
kvmarm@lists.cs.columbia.edu,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file
Date: Mon, 22 Jul 2019 17:38:12 +0100 [thread overview]
Message-ID: <20190722163811.GJ60625@arrakis.emea.arm.com> (raw)
In-Reply-To: <CAJF2gTTEbhA-pZCPGuUNqXT9F-vk8fSTyNJyEOpn=QE=toAN3g@mail.gmail.com>
On Tue, Jul 16, 2019 at 11:31:27AM +0800, Guo Ren wrote:
> I saw arm64 to prevent speculation by temporarily setting TTBR0.el1 to
> a zero page table. Is that used to prevent speculative execution user
> space code or just prevent ld/st in copy_use_* ?
Only to prevent explicit ld/st from user. On ARMv8.1+, we don't normally
use the TTBR0 trick but rather disable user space access using the PAN
(privileged access never) feature. However, I don't think PAN disables
speculative accesses, only explicit loads/stores. Also, with ARMv8.2
Linux uses the LDTR/STTR instructions in copy_*_user() which don't need
to disable PAN explicitly.
--
Catalin
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-07-22 16:38 UTC|newest]
Thread overview: 211+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-21 16:36 [PATCH RFC 00/14] kvm/arm: Align the VMID allocation with the arm64 ASID one Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 01/14] arm64/mm: Introduce asid_info structure and move asid_generation/asid_map to it Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 17:03 ` Suzuki K Poulose
2019-03-21 17:03 ` Suzuki K Poulose
2019-03-21 17:27 ` Julien Grall
2019-03-21 17:27 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 02/14] arm64/mm: Move active_asids and reserved_asids to asid_info Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 03/14] arm64/mm: Move bits " Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 04/14] arm64/mm: Move the variable lock and tlb_flush_pending " Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 05/14] arm64/mm: Remove dependency on MM in new_context Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 06/14] arm64/mm: Store the number of asid allocated per context Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 07/14] arm64/mm: Introduce NUM_ASIDS Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 08/14] arm64/mm: Split asid_inits in 2 parts Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 09/14] arm64/mm: Split the function check_and_switch_context in 3 parts Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 10/14] arm64/mm: Introduce a callback to flush the local context Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 11/14] arm64: Move the ASID allocator code in a separate file Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-06-05 16:56 ` Julien Grall
2019-06-05 16:56 ` Julien Grall
2019-06-05 16:56 ` Julien Grall
2019-06-05 16:56 ` Julien Grall
2019-06-05 20:41 ` Palmer Dabbelt
2019-06-05 20:41 ` Palmer Dabbelt
2019-06-05 20:41 ` Palmer Dabbelt
2019-06-05 20:41 ` Palmer Dabbelt
2019-06-11 1:56 ` Gary Guo
2019-06-11 1:56 ` Gary Guo
2019-06-11 1:56 ` Gary Guo
2019-06-11 1:56 ` Gary Guo
2019-06-19 8:07 ` Guo Ren
2019-06-19 8:07 ` Guo Ren
2019-06-19 8:07 ` Guo Ren
2019-06-19 8:07 ` Guo Ren
2019-06-19 8:54 ` Julien Grall
2019-06-19 8:54 ` Julien Grall
2019-06-19 8:54 ` Julien Grall
2019-06-19 8:54 ` Julien Grall
2019-06-19 9:12 ` Will Deacon
2019-06-19 9:12 ` Will Deacon
2019-06-19 9:12 ` Will Deacon
2019-06-19 9:12 ` Will Deacon
2019-06-19 12:18 ` Guo Ren
2019-06-19 12:18 ` Guo Ren
2019-06-19 12:18 ` Guo Ren
2019-06-19 12:18 ` Guo Ren
2019-06-19 12:39 ` Will Deacon
2019-06-19 12:39 ` Will Deacon
2019-06-19 12:39 ` Will Deacon
2019-06-19 12:39 ` Will Deacon
2019-06-20 9:33 ` Guo Ren
2019-06-20 9:33 ` Guo Ren
2019-06-20 9:33 ` Guo Ren
2019-06-20 9:33 ` Guo Ren
2019-06-24 10:40 ` Will Deacon
2019-06-24 10:40 ` Will Deacon
2019-06-24 10:40 ` Will Deacon
2019-06-24 10:40 ` Will Deacon
2019-06-25 7:25 ` Palmer Dabbelt
2019-06-25 7:25 ` Palmer Dabbelt
2019-06-25 7:25 ` Palmer Dabbelt
2019-06-25 7:25 ` Palmer Dabbelt
2019-09-07 23:52 ` Guo Ren
2019-09-07 23:52 ` Guo Ren
2019-09-07 23:52 ` Guo Ren
2019-09-07 23:52 ` Guo Ren
2019-09-07 23:52 ` Guo Ren
2019-09-12 14:02 ` Will Deacon
2019-09-12 14:02 ` Will Deacon
2019-09-12 14:02 ` Will Deacon
2019-09-12 14:02 ` Will Deacon
2019-09-12 14:02 ` Will Deacon
2019-09-12 14:59 ` Guo Ren
2019-09-12 14:59 ` Guo Ren
2019-09-12 14:59 ` Guo Ren
2019-09-12 14:59 ` Guo Ren
2019-09-12 14:59 ` Guo Ren
2019-09-13 7:13 ` Guo Ren
2019-09-13 7:13 ` Guo Ren
2019-09-14 8:49 ` Guo Ren
2019-09-14 8:49 ` Guo Ren
2019-09-14 8:49 ` Guo Ren
2019-09-14 8:49 ` Guo Ren
2019-09-14 8:49 ` Guo Ren
2019-09-16 12:57 ` Jean-Philippe Brucker
2019-09-16 12:57 ` Jean-Philippe Brucker
2019-09-16 12:57 ` Jean-Philippe Brucker
2019-09-16 12:57 ` Jean-Philippe Brucker
2019-09-16 12:57 ` Jean-Philippe Brucker
2019-09-19 13:07 ` Guo Ren
2019-09-19 13:07 ` Guo Ren
2019-09-19 13:07 ` Guo Ren
2019-09-19 13:07 ` Guo Ren
2019-09-19 13:07 ` Guo Ren
2019-09-19 15:18 ` Jean-Philippe Brucker
2019-09-19 15:18 ` Jean-Philippe Brucker
2019-09-19 15:18 ` Jean-Philippe Brucker
2019-09-19 15:18 ` Jean-Philippe Brucker
2019-09-19 15:18 ` Jean-Philippe Brucker
2019-09-20 0:07 ` Guo Ren
2019-09-20 0:07 ` Guo Ren
2019-09-20 0:07 ` Guo Ren
2019-09-20 0:07 ` Guo Ren
2019-09-20 0:07 ` Guo Ren
2019-09-20 7:18 ` Jean-Philippe Brucker
2019-09-20 7:18 ` Jean-Philippe Brucker
2019-09-20 7:18 ` Jean-Philippe Brucker
2019-09-20 7:18 ` Jean-Philippe Brucker
2019-09-20 7:18 ` Jean-Philippe Brucker
2019-09-14 14:01 ` Palmer Dabbelt
2019-09-14 14:01 ` Palmer Dabbelt
2019-09-14 14:01 ` Palmer Dabbelt
2019-09-14 14:01 ` Palmer Dabbelt
2019-09-14 14:01 ` Palmer Dabbelt
2019-09-15 5:03 ` Anup Patel
2019-09-15 5:03 ` Anup Patel
2019-09-15 5:03 ` Anup Patel
2019-09-15 5:03 ` Anup Patel
2019-09-15 5:03 ` Anup Patel
2019-09-16 18:18 ` Will Deacon
2019-09-16 18:18 ` Will Deacon
2019-09-16 18:18 ` Will Deacon
2019-09-16 18:18 ` Will Deacon
2019-09-16 18:18 ` Will Deacon
2019-09-16 18:28 ` Palmer Dabbelt
2019-09-16 18:28 ` Palmer Dabbelt
2019-09-16 18:28 ` Palmer Dabbelt
2019-09-16 18:28 ` Palmer Dabbelt
2019-09-16 18:28 ` Palmer Dabbelt
2019-09-17 3:42 ` Anup Patel
2019-09-17 3:42 ` Anup Patel
2019-09-17 3:42 ` Anup Patel
2019-09-17 3:42 ` Anup Patel
2019-09-17 3:42 ` Anup Patel
2019-09-19 13:36 ` Guo Ren
2019-09-19 13:36 ` Guo Ren
2019-09-19 13:36 ` Guo Ren
2019-09-19 13:36 ` Guo Ren
2019-09-19 13:36 ` Guo Ren
2019-06-19 11:51 ` Guo Ren
2019-06-19 11:51 ` Guo Ren
2019-06-19 11:51 ` Guo Ren
2019-06-19 11:51 ` Guo Ren
2019-06-19 12:52 ` Julien Grall
2019-06-19 12:52 ` Julien Grall
2019-06-19 12:52 ` Julien Grall
2019-06-19 12:52 ` Julien Grall
2019-06-21 14:16 ` Catalin Marinas
2019-06-21 14:16 ` Catalin Marinas
2019-06-21 14:16 ` Catalin Marinas
2019-06-21 14:16 ` Catalin Marinas
2019-06-23 16:35 ` Guo Ren
2019-06-23 16:35 ` Guo Ren
2019-06-23 16:35 ` Guo Ren
2019-06-23 16:35 ` Guo Ren
2019-06-24 10:22 ` Will Deacon
2019-06-24 10:22 ` Will Deacon
2019-06-24 10:22 ` Will Deacon
2019-06-24 10:22 ` Will Deacon
2019-06-27 9:41 ` qi.fuli
2019-06-27 9:41 ` qi.fuli
2019-06-27 9:41 ` qi.fuli
2019-06-27 9:41 ` qi.fuli
2019-06-27 10:26 ` Will Deacon
2019-06-27 10:26 ` Will Deacon
2019-06-27 10:26 ` Will Deacon
2019-06-27 10:26 ` Will Deacon
2019-06-24 15:38 ` Catalin Marinas
2019-06-24 15:38 ` Catalin Marinas
2019-06-24 15:38 ` Catalin Marinas
2019-06-24 15:38 ` Catalin Marinas
2019-06-30 4:29 ` Guo Ren
2019-06-30 4:29 ` Guo Ren
2019-06-30 4:29 ` Guo Ren
2019-06-30 4:29 ` Guo Ren
2019-07-01 9:17 ` Catalin Marinas
2019-07-01 9:17 ` Catalin Marinas
2019-07-01 9:17 ` Catalin Marinas
2019-07-01 9:17 ` Catalin Marinas
2019-07-16 3:31 ` Guo Ren
2019-07-16 3:31 ` Guo Ren
2019-07-16 3:31 ` Guo Ren
2019-07-16 3:31 ` Guo Ren
2019-07-22 16:38 ` Catalin Marinas [this message]
2019-07-22 16:38 ` Catalin Marinas
2019-07-22 16:38 ` Catalin Marinas
2019-07-22 16:38 ` Catalin Marinas
2019-03-21 16:36 ` [PATCH RFC 12/14] arm64/lib: asid: Allow user to update the context under the lock Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 13/14] arm/kvm: Introduce a new VMID allocator Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` [PATCH RFC 14/14] kvm/arm: Align the VMID allocation with the arm64 ASID one Julien Grall
2019-03-21 16:36 ` Julien Grall
2019-03-21 16:36 ` Julien Grall
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