linux-kernel - Re: WARNING: CPU: 0 PID: 3031 at ./arch/x86/include/asm/fpu/internal.h:530 fpu_

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: <20160212170010.GE4099@pd.tnic>
Date:	Fri, 12 Feb 2016 18:00:10 +0100
From:	Borislav Petkov <bp@...en8.de>
To:	Andy Lutomirski <luto@...capital.net>
Cc:	x86-ml <x86@...nel.org>, lkml <linux-kernel@...r.kernel.org>
Subject: Re: WARNING: CPU: 0 PID: 3031 at
 ./arch/x86/include/asm/fpu/internal.h:530 fpu__restore+0x90/0x130()

On Thu, Feb 11, 2016 at 05:16:00PM -0800, Andy Lutomirski wrote:
>         fpu__drop(fpu);
>         if (__copy_from_user(&fpu->state.xsave, buf_fx, state_size) ||
>             __copy_from_user(&env, buf, sizeof(env))) {
>             fpstate_init(&fpu->state);
>             err = -1;
>         } else {
>             sanitize_restored_xstate(tsk, &env, xfeatures, fx_only);
>         }
> 
>         fpu->fpstate_active = 1;
> 
> <-- preempted right here

>From IRC:

<amluto> you could try sticking a schedule() right after that fpu->fpstate_active = 1; line

>         if (use_eager_fpu()) {
>             preempt_disable();
>             fpu__restore(fpu);
>             preempt_enable();

Something for me to try when I get a chance.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.