From: Dave Hansen <dave@sr71.net>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de,
dave.hansen@linux.intel.com, oleg@redhat.com, bp@alien8.de,
riel@redhat.com, sbsiddha@gmail.com, luto@amacapital.net,
mingo@redhat.com, hpa@zytor.com, fenghua.yu@intel.com
Subject: Re: [PATCH 02/19] x86, fpu: Wrap get_xsave_addr() to make it safer
Date: Thu, 28 May 2015 07:45:18 -0700 [thread overview]
Message-ID: <556729FE.1020007@sr71.net> (raw)
In-Reply-To: <20150528084140.GA31719@gmail.com>
On 05/28/2015 01:41 AM, Ingo Molnar wrote:
> What you want here is to make the (in-memory) FPU state valid and current, before
> reading it, and the function to use for that is fpu__activate_fpstate_read()
> (available in the latest tip:x86/fpu tree).
Do we really want to unconditionally activate the FPU?
Let's say supporting MPX didn't require eager mode and someone called
get_xsave_addr(). We would ideally want to keep the FPU inactive and
just return NULL. Right?
next prev parent reply other threads:[~2015-05-28 14:45 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-27 18:36 [PATCH 00/19] x86, mpx updates for 4.2 (take 8) Dave Hansen
2015-05-27 18:36 ` [PATCH 01/19] x86, mpx, xsave: Fix up bad get_xsave_addr() assumptions Dave Hansen
2015-05-27 18:36 ` [PATCH 02/19] x86, fpu: Wrap get_xsave_addr() to make it safer Dave Hansen
2015-05-28 8:41 ` Ingo Molnar
2015-05-28 14:45 ` Dave Hansen [this message]
2015-05-28 15:01 ` Ingo Molnar
2015-05-28 16:02 ` Dave Hansen
2015-05-29 18:49 ` Ingo Molnar
2015-05-28 16:24 ` Dave Hansen
2015-05-29 1:05 ` Andy Lutomirski
2015-05-29 15:31 ` Dave Hansen
2015-05-29 16:10 ` Borislav Petkov
2015-05-29 18:51 ` Ingo Molnar
2015-05-29 18:17 ` Ingo Molnar
2015-05-29 18:29 ` Andy Lutomirski
2015-05-29 18:44 ` Ingo Molnar
2015-05-29 16:47 ` Dave Hansen
2015-05-29 18:48 ` Ingo Molnar
2015-05-27 18:36 ` [PATCH 03/19] x86, mpx: Use new get_xsave_field_ptr() Dave Hansen
2015-05-27 18:36 ` [PATCH 05/19] x86, mpx: remove redundant MPX_BNDCFG_ADDR_MASK Dave Hansen
2015-05-27 18:36 ` [PATCH 04/19] x86, mpx: Cleanup: Do not pass task around when unnecessary Dave Hansen
2015-05-27 18:36 ` [PATCH 06/19] x86, mpx: Restrict mmap size check to bounds tables Dave Hansen
2015-05-27 18:36 ` [PATCH 07/19] x86, mpx: boot-time disable Dave Hansen
2015-05-27 18:36 ` [PATCH 10/19] x86, mpx: Trace the attempts to find bounds tables Dave Hansen
2015-05-27 18:36 ` [PATCH 11/19] x86, mpx: trace allocation of new " Dave Hansen
2015-05-27 18:36 ` [PATCH 08/19] x86, mpx: trace #BR exceptions Dave Hansen
2015-05-27 18:36 ` [PATCH 09/19] x86, mpx: trace entry to bounds exception paths Dave Hansen
2015-05-27 18:36 ` [PATCH 12/19] x86: make is_64bit_mm() widely available Dave Hansen
2015-05-27 18:36 ` [PATCH 14/19] x86, mpx: new directory entry to addr helper Dave Hansen
2015-05-27 18:36 ` [PATCH 13/19] x86, mpx: Add temporary variable to reduce masking Dave Hansen
2015-05-27 18:36 ` [PATCH 17/19] x86, mpx: rewrite unmap code Dave Hansen
2015-05-27 18:36 ` [PATCH 16/19] x86, mpx: support 32-bit binaries on 64-bit kernel Dave Hansen
2015-05-27 18:36 ` [PATCH 15/19] x86, mpx: do 32-bit-only cmpxchg for 32-bit apps Dave Hansen
2015-05-27 18:36 ` [PATCH 18/19] x86, mpx: do not count MPX VMAs as neighbors when unmapping Dave Hansen
2015-05-27 18:36 ` [PATCH 19/19] x86, mpx: allow mixed binaries again Dave Hansen
-- strict thread matches above, loose matches on Subject: below --
2015-06-07 18:37 [PATCH 00/19] x86, mpx updates for 4.2 (take 9) Dave Hansen
2015-06-07 18:37 ` [PATCH 02/19] x86, fpu: Wrap get_xsave_addr() to make it safer Dave Hansen
2015-05-29 22:34 [PATCH 00/19] x86, mpx updates for 4.2 (take 8) Dave Hansen
2015-05-29 22:34 ` [PATCH 02/19] x86, fpu: Wrap get_xsave_addr() to make it safer Dave Hansen
2015-05-19 6:25 [PATCH 00/19] x86, mpx updates for 4.2 (take 7) Dave Hansen
2015-05-19 6:25 ` [PATCH 02/19] x86, fpu: Wrap get_xsave_addr() to make it safer Dave Hansen
2015-05-19 8:15 ` Thomas Gleixner
2015-05-08 18:59 [PATCH 00/19] x86, mpx updates for 4.2 (take 6) Dave Hansen
2015-05-08 18:59 ` [PATCH 02/19] x86, fpu: wrap get_xsave_addr() to make it safer Dave Hansen
2015-05-18 19:38 ` Thomas Gleixner
2015-05-18 19:42 ` Thomas Gleixner
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