Andy Lutomirski 37868fe113 x86/ldt: Make modify_ldt synchronous ...

modify_ldt() has questionable locking and does not synchronize
threads.  Improve it: redesign the locking and synchronize all
threads' LDTs using an IPI on all modifications.

This will dramatically slow down modify_ldt in multithreaded
programs, but there shouldn't be any multithreaded programs that
care about modify_ldt's performance in the first place.

This fixes some fallout from the CVE-2015-5157 fixes.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org <security@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/4c6978476782160600471bd865b318db34c7b628.1438291540.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2015-07-31 10:23:23 +02:00

..

mcheck

Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 17:59:09 -07:00

microcode

x86/microcode: Correct CPU family related variable types

2015-06-07 15:38:15 +02:00

mtrr

x86/mm/pat: Wrap pat_enabled into a function API

2015-05-27 14:41:01 +02:00

.gitignore

…

amd.c

Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 17:59:09 -07:00

bugs_64.c

…

bugs.c

x86/fpu: Move various internal function prototypes to fpu/internal.h

2015-05-19 15:47:48 +02:00

centaur.c

x86: Remove CONFIG_X86_OOSTORE

2014-03-11 10:16:18 -07:00

common.c

x86/ldt: Make modify_ldt synchronous

2015-07-31 10:23:23 +02:00

cpu.h

x86/cpu: Track legacy CPU model data only on 32-bit kernels

2013-10-26 13:34:39 +02:00

cyrix.c

x86: Delete non-required instances of include <linux/init.h>

2014-01-06 21:25:18 -08:00

hypervisor.c

hypervisor/x86/xen: Unset X86_BUG_SYSRET_SS_ATTRS on Xen PV guests

2015-05-05 18:27:43 +01:00

intel_cacheinfo.c

x86: Kill CONFIG_X86_HT

2015-06-07 15:33:44 +02:00

intel_pt.h

perf/x86/intel/pt: Add Intel PT PMU driver

2015-04-02 17:14:20 +02:00

intel.c

x86/cpu/intel: Fix trivial typo in intel_tlb_table[]

2015-02-22 08:55:58 +01:00

Makefile

perf/x86/intel/bts: Add BTS PMU driver

2015-04-02 17:14:21 +02:00

match.c

x86: align x86 arch with generic CPU modalias handling

2014-02-18 12:45:38 -08:00

mkcapflags.sh

x86/build: Fix mkcapflags.sh bash-ism

2015-02-19 02:21:00 +01:00

mshyperv.c

x86: Use entering[_ack]_irq() instead of open coding it

2015-05-15 16:03:18 +02:00

perf_event_amd_ibs.c

perf/x86/amd/ibs: Convert force_ibs_eilvt_setup() to void

2015-02-18 17:01:46 +01:00

perf_event_amd_iommu.c

cpumask: factor out show_cpumap into separate helper function

2014-11-07 11:45:00 -08:00

perf_event_amd_iommu.h

perf/x86/amd: AMD IOMMU Performance Counter PERF uncore PMU implementation

2013-06-19 13:04:53 +02:00

perf_event_amd_uncore.c

cpumask: factor out show_cpumap into separate helper function

2014-11-07 11:45:00 -08:00

perf_event_amd.c

perf/x86: Add 'index' param to get_event_constraint() callback

2015-04-02 17:33:10 +02:00

perf_event_intel_bts.c

Merge tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2015-07-02 10:36:29 -07:00

perf_event_intel_cqm.c

perf/x86/intel/cqm: Return cached counter value from IRQ context

2015-07-26 10:22:29 +02:00

perf_event_intel_ds.c

perf/x86/intel/pebs: Add PEBSv3 decoding

2015-06-07 16:09:16 +02:00

perf_event_intel_lbr.c

perf/x86/intel: Drain the PEBS buffer during context switches

2015-06-07 16:08:54 +02:00

perf_event_intel_pt.c

Merge tag 'module_init-alternate_initcall-v4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2015-07-02 10:36:29 -07:00

perf_event_intel_rapl.c

Merge branch 'linus' into timers/core

2015-05-19 16:12:32 +02:00

perf_event_intel_uncore_nhmex.c

perf/x86/uncore: Fix coccinelle warnings

2014-08-13 07:51:09 +02:00

perf_event_intel_uncore_snb.c

perf/x86/intel/uncore: Add Broadwell-U uncore IMC PMU support

2015-05-11 11:57:47 +02:00

perf_event_intel_uncore_snbep.c

perf/x86/intel/uncore: Fix CBOX bit wide and UBOX reg on Haswell-EP

2015-06-07 15:46:50 +02:00

perf_event_intel_uncore.c

Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 18:57:44 -07:00

perf_event_intel_uncore.h

Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 15:19:21 -07:00

perf_event_intel.c

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 15:52:04 -07:00

perf_event_knc.c

x86: Replace __get_cpu_var uses

2014-08-26 13:45:49 -04:00

perf_event_p4.c

x86: Replace __get_cpu_var uses

2014-08-26 13:45:49 -04:00

perf_event_p6.c

perf/x86/intel/p6: Add userspace RDPMC quirk for PPro

2014-02-09 13:08:24 +01:00

perf_event.c

x86/ldt: Make modify_ldt synchronous

2015-07-31 10:23:23 +02:00

perf_event.h

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-06-22 15:45:41 -07:00

perfctr-watchdog.c

…

powerflags.c

update AMD powerflags comments

2013-05-28 12:02:10 +02:00

proc.c

x86: Replace cpu_**_mask() with topology_**_cpumask()

2015-05-27 15:22:17 +02:00

rdrand.c

x86, rdrand: When nordrand is specified, disable RDSEED as well

2014-05-11 20:25:20 -07:00

scattered.c

x86: Add Intel Processor Trace (INTEL_PT) cpu feature detection

2015-04-02 17:14:18 +02:00

topology.c

x86: delete __cpuinit usage from all x86 files

2013-07-14 19:36:56 -04:00

transmeta.c

x86: Delete non-required instances of include <linux/init.h>

2014-01-06 21:25:18 -08:00

umc.c

x86: Delete non-required instances of include <linux/init.h>

2014-01-06 21:25:18 -08:00

vmware.c

x86: Correctly detect hypervisor

2013-08-05 06:35:33 -07:00