linux-kernel - Re: [RFC PATCH 3/3] ARM: vfp: Use cpu pm notifiers to save vfp state

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] [day] [month] [year] [list]

Message-ID: <AANLkTik=RgXyy-RR2aPy4bVeE5XjYTsiHO7OML3ZbU7S@mail.gmail.com>
Date:	Sun, 13 Feb 2011 13:25:05 -0800
From:	Colin Cross <ccross@...roid.com>
To:	Catalin Marinas <catalin.marinas@....com>
Cc:	linux-arm-kernel@...ts.infradead.org, linux@....linux.org.uk,
	santosh.shilimkar@...com, Will Deacon <Will.Deacon@....com>,
	linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH 3/3] ARM: vfp: Use cpu pm notifiers to save vfp state

On Fri, Feb 11, 2011 at 11:50 AM, Colin Cross <ccross@...roid.com> wrote:
>> Something like below (untested):
>>
>>        if (last_VFP_context[cpu]) {
>>                vfp_save_state(last_VFP_context[cpu], fpexc);
>>                /* force a reload when coming back from idle */
>>                last_VFP_context[cpu] = NULL;
>>                fmxr(FPEXC, fpexc & ~FPEXC_EN);
>>        }
One more fix is necessary, the VFP will usually not be enabled when
this is called.  The VFP needs to be enabled before vfp_save_state,
and then disabled after.

>        /* save state for resumption */
>        if (last_VFP_context[ti->cpu]) {
>                printk(KERN_DEBUG "%s: saving vfp state\n", __func__);
>                vfp_save_state(last_VFP_context[ti->cpu], fpexc);
>
>                /* disable, just in case */
>                fmxr(FPEXC, fpexc & ~FPEXC_EN);
>        }
Same fix is needed here.
--
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/