linux-kernel - Re: [PATCH] PCI/ACPI: Disable AER when

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:   Thu, 11 Jan 2018 20:04:16 +0100
From:   Borislav Petkov <bp@...e.de>
To:     "Rafael J. Wysocki" <rafael@...nel.org>
Cc:     "Ghannam, Yazen" <Yazen.Ghannam@....com>,
        ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Linux PCI <linux-pci@...r.kernel.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Len Brown <lenb@...nel.org>,
        Bjorn Helgaas <bhelgaas@...gle.com>
Subject: Re: [PATCH] PCI/ACPI: Disable AER when _OSC control bit is clear.

On Thu, Jan 11, 2018 at 07:03:23PM +0100, Rafael J. Wysocki wrote:
> >> > +       if (!(requested & control & OSC_PCI_EXPRESS_AER_CONTROL))
> >>
> >> One of the operators above needs to be a && I suppose?
> >>
> >
> > It's a 3-way bitwise AND to check that OSC_PCI_EXPRESS_AER_CONTROL is
> > set in both "requested" and "control".
> >
> > IOW, we check if AER was requested by the OS and that the platform
> > granted the request.
> 
> OK

This definitely needs a comment - people will keep tripping over this.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--