From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: KarimAllah Ahmed <karahmed@amazon.de>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
pbonzini@redhat.com, rkrcmar@redhat.com
Subject: Re: [PATCH v5 00/13] KVM/X86: Introduce a new guest mapping interface
Date: Wed, 23 Jan 2019 13:16:39 -0500 [thread overview]
Message-ID: <20190123181636.GR19289@Konrads-MacBook-Pro.local> (raw)
In-Reply-To: <1547026933-31226-1-git-send-email-karahmed@amazon.de>
On Wed, Jan 09, 2019 at 10:42:00AM +0100, KarimAllah Ahmed wrote:
> Guest memory can either be directly managed by the kernel (i.e. have a "struct
> page") or they can simply live outside kernel control (i.e. do not have a
> "struct page"). KVM mostly support these two modes, except in a few places
> where the code seems to assume that guest memory must have a "struct page".
>
> This patchset introduces a new mapping interface to map guest memory into host
> kernel memory which also supports PFN-based memory (i.e. memory without 'struct
> page'). It also converts all offending code to this interface or simply
> read/write directly from guest memory. Patch 2 is additionally fixing an
> incorrect page release and marking the page as dirty (i.e. as a side-effect of
> using the helper function to write).
>
> As far as I can see all offending code is now fixed except the APIC-access page
> which I will handle in a seperate series along with dropping
> kvm_vcpu_gfn_to_page and kvm_vcpu_gpa_to_page from the internal KVM API.
>
> The current implementation of the new API uses memremap to map memory that does
> not have a "struct page". This proves to be very slow for high frequency
> mappings. Since this does not affect the normal use-case where a "struct page"
> is available, the performance of this API will be handled by a seperate patch
> series.
Where could one find this patchset?
Also is there an simple test-case (or a writeup) you have for testing
this code? Specifically I am thinking about the use-case of "memory
without the 'struct page'"
And thank you for posting this patchset. It was a pleasure reviewing the
code!
next prev parent reply other threads:[~2019-01-23 18:17 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-09 9:42 [PATCH v5 00/13] KVM/X86: Introduce a new guest mapping interface KarimAllah Ahmed
2019-01-09 9:42 ` [PATCH v5 01/13] X86/nVMX: handle_vmon: Read 4 bytes from guest memory KarimAllah Ahmed
2019-01-23 16:59 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 02/13] X86/nVMX: Update the PML table without mapping and unmapping the page KarimAllah Ahmed
2019-01-23 17:17 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 03/13] X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs KarimAllah Ahmed
2019-01-23 17:31 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 04/13] KVM: Introduce a new guest mapping API KarimAllah Ahmed
2019-01-10 13:07 ` David Hildenbrand
2019-01-25 18:01 ` Raslan, KarimAllah
2019-01-23 17:41 ` Konrad Rzeszutek Wilk
2019-01-23 17:50 ` Konrad Rzeszutek Wilk
2019-01-25 18:09 ` Raslan, KarimAllah
2019-01-30 17:08 ` Paolo Bonzini
2019-01-09 9:42 ` [PATCH v5 05/13] X86/nVMX: handle_vmptrld: Use kvm_vcpu_map when copying VMCS12 from guest memory KarimAllah Ahmed
2019-01-23 17:44 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 06/13] KVM/nVMX: Use kvm_vcpu_map when mapping the L1 MSR bitmap KarimAllah Ahmed
2019-01-09 9:42 ` [PATCH v5 07/13] KVM/nVMX: Use kvm_vcpu_map when mapping the virtual APIC page KarimAllah Ahmed
2019-01-23 17:57 ` Konrad Rzeszutek Wilk
2019-01-25 18:14 ` Raslan, KarimAllah
2019-01-09 9:42 ` [PATCH v5 08/13] KVM/nVMX: Use kvm_vcpu_map when mapping the posted interrupt descriptor table KarimAllah Ahmed
2019-01-23 18:03 ` Konrad Rzeszutek Wilk
2019-01-25 18:15 ` Raslan, KarimAllah
2019-01-09 9:42 ` [PATCH v5 09/13] KVM/X86: Use kvm_vcpu_map in emulator_cmpxchg_emulated KarimAllah Ahmed
2019-01-23 18:04 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 10/13] KVM/nSVM: Use the new mapping API for mapping guest memory KarimAllah Ahmed
2019-01-23 18:08 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 11/13] KVM/nVMX: Use kvm_vcpu_map for accessing the shadow VMCS KarimAllah Ahmed
2019-01-23 18:10 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 12/13] KVM/nVMX: Use kvm_vcpu_map for accessing the enlightened VMCS KarimAllah Ahmed
2019-01-23 18:11 ` Konrad Rzeszutek Wilk
2019-01-09 9:42 ` [PATCH v5 13/13] KVM/nVMX: Use page_address_valid in a few more locations KarimAllah Ahmed
2019-01-23 18:18 ` Konrad Rzeszutek Wilk
2019-01-25 18:17 ` Raslan, KarimAllah
2019-01-23 18:16 ` Konrad Rzeszutek Wilk [this message]
2019-01-25 18:28 ` [PATCH v5 00/13] KVM/X86: Introduce a new guest mapping interface Raslan, KarimAllah
2019-01-30 17:14 ` Paolo Bonzini
2019-01-31 13:03 ` Raslan, KarimAllah
2019-01-31 13:10 ` Paolo Bonzini
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