linux-kernel - Re: [PATCH v3 5/9] x86/mm/tlb: Privatize cpu

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:   Fri, 19 Jul 2019 11:48:13 -0700
From:   Dave Hansen <dave.hansen@...el.com>
To:     Nadav Amit <namit@...are.com>
Cc:     Andy Lutomirski <luto@...nel.org>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        the arch/x86 maintainers <x86@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>
Subject: Re: [PATCH v3 5/9] x86/mm/tlb: Privatize cpu_tlbstate

On 7/19/19 11:43 AM, Nadav Amit wrote:
> Andy said that for the lazy tlb optimizations there might soon be more
> shared state. If you prefer, I can move is_lazy outside of tlb_state, and
> not set it in any alternative struct.

I just wanted to make sure that we capture these rules:

1. If the data is only ever accessed on the "owning" CPU via
   this_cpu_*(), put it in 'tlb_state'.
2. If the data is read by other CPUs, put it in 'tlb_state_shared'.

I actually like the idea of having two structs.