linux-kernel - Re: [PATCH 4/4] x86/fpu: don't abuse drop_init_fpu() in flush

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150316143944.GA3300@redhat.com>
Date:	Mon, 16 Mar 2015 15:39:44 +0100
From:	Oleg Nesterov <oleg@...hat.com>
To:	Borislav Petkov <bp@...e.de>
Cc:	Dave Hansen <dave.hansen@...el.com>,
	Ingo Molnar <mingo@...nel.org>,
	Andy Lutomirski <luto@...capital.net>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Pekka Riikonen <priikone@....fi>,
	Rik van Riel <riel@...hat.com>,
	Suresh Siddha <sbsiddha@...il.com>,
	LKML <linux-kernel@...r.kernel.org>,
	"Yu, Fenghua" <fenghua.yu@...el.com>,
	Quentin Casasnovas <quentin.casasnovas@...cle.com>
Subject: Re: [PATCH 4/4] x86/fpu: don't abuse drop_init_fpu() in
	flush_thread()

On 03/16, Borislav Petkov wrote:
>
> -static inline void drop_init_fpu(struct task_struct *tsk)
> +/*
> + * Reset the FPU state in the eager case and drop it in the lazy case (later use
> + * will reinit it).
> + */
> +static inline void fpu_reset_state(struct task_struct *tsk)

ACK!

Perhaps you can also find a beter name for __save_init_fpu/etc ;) The
name clearly suggests that it does "save + init" while in fact it does
"save and may be destroy FPU state". At least for the callers, the fact
that "destroy" is actually "init" doesn't really matter.

But lets not rename it right now. This can conflict with the fixes we
need to do first.

Oleg.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/