linux-stable.git/arch/x86/kernel/microcode_core.c, branch linux-3.4.y

x86, microcode: Sanitize per-cpu microcode reloading interface

2012-08-15T15:10:31+00:00

commit c9fc3f778a6a215ace14ee556067c73982b6d40f upstream.

Microcode reloading in a per-core manner is a very bad idea for both
major x86 vendors. And the thing is, we have such interface with which
we can end up with different microcode versions applied on different
cores of an otherwise homogeneous wrt (family,model,stepping) system.

So turn off the possibility of doing that per core and allow it only
system-wide.

This is a minimal fix which we'd like to see in stable too thus the
more-or-less arbitrary decision to allow system-wide reloading only on
the BSP:

$ echo 1 > /sys/devices/system/cpu/cpu0/microcode/reload
...

and disable the interface on the other cores:

$ echo 1 > /sys/devices/system/cpu/cpu23/microcode/reload
-bash: echo: write error: Invalid argument

Also, allowing the reload only from one CPU (the BSP in
that case) doesn't allow the reload procedure to degenerate
into an O(n^2) deal when triggering reloads from all
/sys/devices/system/cpu/cpuX/microcode/reload sysfs nodes
simultaneously.

A more generic fix will follow.

Signed-off-by: Borislav Petkov 
Cc: Henrique de Moraes Holschuh 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1340280437-7718-2-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86, microcode: microcode_core.c simple_strtoul cleanup

2012-08-15T15:10:31+00:00

commit e826abd523913f63eb03b59746ffb16153c53dc4 upstream.

Change reload_for_cpu() in kernel/microcode_core.c to call kstrtoul()
instead of calling obsoleted simple_strtoul().

Signed-off-by: Shuah Khan 
Reviewed-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1336324264.2897.9.camel@lorien2
Signed-off-by: H. Peter Anvin 
Cc: Henrique de Moraes Holschuh 
Signed-off-by: Greg Kroah-Hartman

x86, microcode: Ensure that module is only loaded on supported AMD CPUs

2012-04-13T09:51:05+00:00

Exit early when there's no support for a particular CPU family. Also,
fixup the "no support for this CPU vendor" to be issued only when the
driver is attempted to be loaded on an unsupported vendor.

Cc: stable@vger.kernel.org
Cc: Tigran Aivazian 
Signed-off-by: Andreas Herrmann 
Acked-by: Greg Kroah-Hartman 
Link: http://lkml.kernel.org/r/20120411163849.GE4794@alberich.amd.com
[Boris: add a commit msg because Andreas is lazy]
Signed-off-by: Borislav Petkov

x86, microcode: Fix sysfs warning during module unload on unsupported CPUs

2012-04-13T09:49:06+00:00

Loading the microcode driver on an unsupported CPU and subsequently
unloading the driver causes

 WARNING: at fs/sysfs/group.c:138 mc_device_remove+0x5f/0x70 [microcode]()
 Hardware name: 01972NG
 sysfs group ffffffffa00013d0 not found for kobject 'cpu0'
 Modules linked in: snd_hda_codec_hdmi snd_hda_codec_conexant snd_hda_intel btusb snd_hda_codec bluetooth thinkpad_acpi rfkill microcode(-) [last unloaded: cfg80211]
 Pid: 4560, comm: modprobe Not tainted 3.4.0-rc2-00002-g258f742 #5
 Call Trace:
  [] ? warn_slowpath_common+0x7b/0xc0
  [] ? warn_slowpath_fmt+0x45/0x50
  [] ? sysfs_remove_group+0x34/0x120
  [] ? mc_device_remove+0x5f/0x70 [microcode]
  [] ? subsys_interface_unregister+0x69/0xa0
  [] ? mutex_lock+0x16/0x40
  [] ? microcode_exit+0x50/0x92 [microcode]
  [] ? sys_delete_module+0x16d/0x260
  [] ? wait_iff_congested+0x45/0x110
  [] ? page_fault+0x1f/0x30
  [] ? system_call_fastpath+0x16/0x1b

on recent kernels.

This is due to commit 8a25a2fd126c ("cpu: convert 'cpu' and
'machinecheck' sysdev_class to a regular subsystem") which renders
commit 6c53cbfced04 ("x86, microcode: Correct sysdev_add error path")
useless.

See http://marc.info/?l=linux-kernel&m=133416246406478

Avoid above warning by restoring the old driver behaviour before
6c53cbfced04 ("x86, microcode: Correct sysdev_add error path").

Cc: stable@vger.kernel.org
Cc: Tigran Aivazian 
Signed-off-by: Andreas Herrmann 
Acked-by: Greg Kroah-Hartman 
Link: http://lkml.kernel.org/r/20120411163849.GE4794@alberich.amd.com
Signed-off-by: Borislav Petkov

x86: autoload microcode driver on Intel and AMD systems v2

2012-01-27T00:49:07+00:00

Don't try to describe the actual models for now.

v2: Fix typo: X86_VENDOR_ANY -> X86_FAMILY_ANY (trenn)

Signed-off-by: Andi Kleen 
Signed-off-by: Thomas Renninger 
Acked-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2012-01-07T20:03:30+00:00

* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
  arm: fix up some samsung merge sysdev conversion problems
  firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
  Drivers:hv: Fix a bug in vmbus_driver_unregister()
  driver core: remove __must_check from device_create_file
  debugfs: add missing #ifdef HAS_IOMEM
  arm: time.h: remove device.h #include
  driver-core: remove sysdev.h usage.
  clockevents: remove sysdev.h
  arm: convert sysdev_class to a regular subsystem
  arm: leds: convert sysdev_class to a regular subsystem
  kobject: remove kset_find_obj_hinted()
  m86k: gpio - convert sysdev_class to a regular subsystem
  mips: txx9_sram - convert sysdev_class to a regular subsystem
  mips: 7segled - convert sysdev_class to a regular subsystem
  sh: dma - convert sysdev_class to a regular subsystem
  sh: intc - convert sysdev_class to a regular subsystem
  power: suspend - convert sysdev_class to a regular subsystem
  power: qe_ic - convert sysdev_class to a regular subsystem
  power: cmm - convert sysdev_class to a regular subsystem
  s390: time - convert sysdev_class to a regular subsystem
  ...

Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
 - arch/arm/mach-exynos/cpu.c
 - arch/arm/mach-exynos/irq-eint.c
 - arch/arm/mach-s3c64xx/common.c
 - arch/arm/mach-s3c64xx/cpu.c
 - arch/arm/mach-s5p64x0/cpu.c
 - arch/arm/mach-s5pv210/common.c
 - arch/arm/plat-samsung/include/plat/cpu.h
 - arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h

Merge branch 'driver-core-next' into Linux 3.2

2012-01-06T19:42:52+00:00

This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.

The microcode_core.c patch was provided by Stephen Rothwell
 who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.

Signed-off-by: Greg Kroah-Hartman

cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem

2011-12-21T22:29:42+00:00

This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.

After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.

Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.

Cc: Haavard Skinnemoen 
Cc: Hans-Christian Egtvedt 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Paul Mundt 
Cc: "David S. Miller" 
Cc: Chris Metcalf 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: Borislav Petkov 
Cc: Tigran Aivazian 
Cc: Len Brown 
Cc: Zhang Rui 
Cc: Dave Jones 
Cc: Peter Zijlstra 
Cc: Russell King 
Cc: Andrew Morton 
Cc: Arjan van de Ven 
Cc: "Rafael J. Wysocki" 
Cc: "Srivatsa S. Bhat" 
Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman

x86, microcode, AMD: Add a vendor-specific exit function

2011-12-14T11:46:47+00:00

This will be used to do cleanup work before the driver exits.

Signed-off-by: Borislav Petkov

x86, microcode: Fix the failure path of microcode update driver init code

2011-12-05T13:21:01+00:00

The microcode update driver's initialization code does not handle
failures correctly. This patch fixes this issue.

Signed-off-by: Jan Beulich 
Signed-off-by: Srivatsa S. Bhat 
Link: http://lkml.kernel.org/r/20111107123530.12164.31227.stgit@srivatsabhat.in.ibm.com
Link: http://lkml.kernel.org/r/4ED8E2270200007800065120@nat28.tlf.novell.com
Signed-off-by: Borislav Petkov