linux-kernel - Re: [PATCH RFC 04/13] iommu/vt-d: Add helper and flag to check/disable posted MSI

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]

Message-ID: <87o7f3uvi7.ffs@tglx>
Date:   Wed, 06 Dec 2023 17:49:04 +0100
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Jacob Pan <jacob.jun.pan@...ux.intel.com>,
        LKML <linux-kernel@...r.kernel.org>, X86 Kernel <x86@...nel.org>,
        iommu@...ts.linux.dev, Lu Baolu <baolu.lu@...ux.intel.com>,
        kvm@...r.kernel.org, Dave Hansen <dave.hansen@...el.com>,
        Joerg Roedel <joro@...tes.org>,
        "H. Peter Anvin" <hpa@...or.com>, Borislav Petkov <bp@...en8.de>,
        Ingo Molnar <mingo@...hat.com>
Cc:     Raj Ashok <ashok.raj@...el.com>,
        "Tian, Kevin" <kevin.tian@...el.com>, maz@...nel.org,
        peterz@...radead.org, seanjc@...gle.com,
        Robin Murphy <robin.murphy@....com>,
        Jacob Pan <jacob.jun.pan@...ux.intel.com>
Subject: Re: [PATCH RFC 04/13] iommu/vt-d: Add helper and flag to
 check/disable posted MSI

On Sat, Nov 11 2023 at 20:16, Jacob Pan wrote:
> Allow command line opt-out posted MSI under CONFIG_X86_POSTED_MSI=y.
> And add a helper function for testing if posted MSI is supported on the
> CPU side.

That's backwards. You want command line opt-in first and not enforce
this posted muck on everyone including RT which will regress and suffer
from that.