linux-kernel - Re: [PATCH V8 26/44] x86/fault: Print PKS MSR on fault

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: <edb6706a-6e06-2510-3bbc-84da97b8cd52@intel.com>
Date:   Fri, 18 Feb 2022 12:20:58 -0800
From:   Dave Hansen <dave.hansen@...el.com>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>,
        "Weiny, Ira" <ira.weiny@...el.com>
Cc:     "hpa@...or.com" <hpa@...or.com>,
        "Williams, Dan J" <dan.j.williams@...el.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "Yu, Fenghua" <fenghua.yu@...el.com>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>
Subject: Re: [PATCH V8 26/44] x86/fault: Print PKS MSR on fault

On 2/18/22 09:28, Edgecombe, Rick P wrote:
> On Thu, 2022-02-17 at 22:01 -0800, Ira Weiny wrote:
>> Are you suggesting the PKRU should be printed instead or in addition
>> to the
>> PKS?
> Well I was just thinking that PKRS should only be printed if it's an
> access via a supervisor pte.

That's not *wrong* per se, but it's not what we do for PKU:

        if (cpu_feature_enabled(X86_FEATURE_OSPKE))
                printk("%sPKRU: %08x\n", log_lvl, read_pkru());

If the feature is enabled, we print the register.  We don't try to be
fancy and decide if it's relevant to the oops.  Why don't you just stick
PKRS on the same line as PKRU whenever it's supported?