linux-kernel - Re: [PATCH v6 05/21] x86/fpu: Make XFD initialization in __fpstate

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: <YdiX5y4KxQ7GY7xn@zn.tnic>
Date:   Fri, 7 Jan 2022 20:43:35 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        guang.zeng@...el.com, jing2.liu@...el.com, kevin.tian@...el.com,
        seanjc@...gle.com, tglx@...utronix.de, wei.w.wang@...el.com,
        yang.zhong@...el.com
Subject: Re: [PATCH v6 05/21] x86/fpu: Make XFD initialization in
 __fpstate_reset() a function argument

On Fri, Jan 07, 2022 at 01:54:56PM -0500, Paolo Bonzini wrote:
> From: Jing Liu <jing2.liu@...el.com>
> 
> vCPU threads are different from native tasks regarding to the initial XFD
> value. While all native tasks follow a fixed value (init_fpstate::xfd)
> established by the FPU core at boot, vCPU threads need to obey the reset
> value (i.e. ZERO) defined by the specification, to meet the expectation of
> the guest.
> 
> Let the caller supply an argument and adjust the host and guest related
> invocations accordingly.
> 
> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>

If Jing is author, then tglx's SOB should come after Jing's to mean,
tglx handled it further.

As it is now, it looks wrong.

Ditto for patches 10, 11, 12, 13.

Also, I wonder if all those Signed-off-by's do mean "handled" or
Co-developed-by but I haven't tracked that particular pile so...

> Signed-off-by: Jing Liu <jing2.liu@...el.com>
> Signed-off-by: Yang Zhong <yang.zhong@...el.com>
> Message-Id: <20220105123532.12586-6-yang.zhong@...el.com>
> Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette