linux-kernel - Re: [PATCH 00/26] KVM: vfio: Hide KVM internals from others

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Mon, 24 Jun 2024 08:32:18 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@...wei.com>
Cc: Catalin Marinas <catalin.marinas@....com>, Will Deacon <will@...nel.org>, 
	Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>, 
	Huacai Chen <chenhuacai@...nel.org>, Michael Ellerman <mpe@...erman.id.au>, 
	Anup Patel <anup@...infault.org>, Paul Walmsley <paul.walmsley@...ive.com>, 
	Palmer Dabbelt <palmer@...belt.com>, Albert Ou <aou@...s.berkeley.edu>, 
	Heiko Carstens <hca@...ux.ibm.com>, Vasily Gorbik <gor@...ux.ibm.com>, 
	Alexander Gordeev <agordeev@...ux.ibm.com>, Christian Borntraeger <borntraeger@...ux.ibm.com>, 
	Janosch Frank <frankja@...ux.ibm.com>, Claudio Imbrenda <imbrenda@...ux.ibm.com>, 
	Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, 
	Dave Hansen <dave.hansen@...ux.intel.com>, "x86@...nel.org" <x86@...nel.org>, 
	Peter Zijlstra <peterz@...radead.org>, Arnaldo Carvalho de Melo <acme@...nel.org>, 
	Paolo Bonzini <pbonzini@...hat.com>, Tony Krowiak <akrowiak@...ux.ibm.com>, 
	Halil Pasic <pasic@...ux.ibm.com>, Jason Herne <jjherne@...ux.ibm.com>, 
	Harald Freudenberger <freude@...ux.ibm.com>, Alex Williamson <alex.williamson@...hat.com>, 
	Andy Lutomirski <luto@...nel.org>, 
	"linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org>, 
	"kvmarm@...ts.linux.dev" <kvmarm@...ts.linux.dev>, 
	"linux-mips@...r.kernel.org" <linux-mips@...r.kernel.org>, "kvm@...r.kernel.org" <kvm@...r.kernel.org>, 
	"linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>, 
	"kvm-riscv@...ts.infradead.org" <kvm-riscv@...ts.infradead.org>, 
	"linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>, 
	"linux-s390@...r.kernel.org" <linux-s390@...r.kernel.org>, 
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, 
	"linux-perf-users@...r.kernel.org" <linux-perf-users@...r.kernel.org>, Anish Ghulati <aghulati@...gle.com>, 
	Venkatesh Srinivas <venkateshs@...omium.org>, Andrew Thornton <andrewth@...gle.com>
Subject: Re: [PATCH 00/26] KVM: vfio: Hide KVM internals from others

On Thu, Jun 20, 2024, Shameerali Kolothum Thodi wrote:
> > This is a borderline RFC series to hide KVM's internals from the rest of
> > the kernel, where "internals" means data structures, enums, #defines,
> > APIs, etc. that are intended to be KVM-only, but are exposed everywhere
> > due to kvm_host.h (and other headers) living in the global include paths.
>
> Hi Sean,
> 
> Just thought of checking with you on this series. Do you have plans to revive this
> series?

Yep!

> The reason I am asking is, on ARM64/KVM side we do have a requirement
> to share the KVM VMID with SMMUV3. Please see the RFC I sent out earlier this
> year[1]. The series basically provides a way for KVM to pin a VMID and also
> associates an iommufd ctx with a struct kvm * to retrieve that VMID. 
> 
> As mentioned above, some of the patches in this series(especially 1-4 & 6) that
> does the VFIO cleanups and dropping CONFIG_KVM_VFIO looks very straightforward
> and useful. I am thinking of including those when I re-spin my RFC series, if
> that’s ok.

Please don't include them, as the patch they build towards (patch 5) is buggy[*],
and I am fairly certain that at least some of the patches will change significantly.

I expect to re-start working on the series in ~2 weeks, and am planning on actively
pushing the series (i.e. not ignoring it for months on end).

[*] https://lore.kernel.org/all/ZWp_q1w01NCZi8KX@google.com

> Please let me know your thoughts.
>
> [1]. https://lore.kernel.org/linux-iommu/20240209115824.GA2922446@myrica