linux-stable.git/arch/x86/kernel/microcode_core.c, branch linux-3.6.y

perf/x86: Fix microcode revision check for SNB-PEBS

2012-08-27T06:48:19+00:00

The following patch makes the microcode update code path
actually invoke the perf_check_microcode() function and
thus potentially renabling SNB PEBS.

By default, CONFIG_MICROCODE_OLD_INTERFACE is
forced to Y in arch/x86/Kconfig. There is no
way to disable this. That means that the code
path used in arch/x86/kernel/microcode_core.c
did not include the call to perf_check_microcode().

Thus, even though the microcode was updated to a
version that fixes the SNB PEBS problem, perf_event
would still return EOPNOTSUPP when enabling precise
sampling.

This patch simply adds a call to perf_check_microcode()
in the call path used when OLD_INTERFACE=y.

Signed-off-by: Stephane Eranian 
Acked-by: Borislav Petkov 
Cc: peterz@infradead.org
Cc: andi@firstfloor.org
Link: http://lkml.kernel.org/r/20120824133434.GA8014@quad
Signed-off-by: Ingo Molnar

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

2012-07-22T19:04:44+00:00

Pull debug-for-linus git tree from Ingo Molnar.

Fix up trivial conflict in arch/x86/kernel/cpu/perf_event_intel.c due to
a printk() having changed to a pr_info() differently in the two branches.

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Move call to print_modules() out of show_regs()
  x86/mm: Mark free_initrd_mem() as __init
  x86/microcode: Mark microcode_id[] as __initconst
  x86/nmi: Clean up register_nmi_handler() usage
  x86: Save cr2 in NMI in case NMIs take a page fault (for i386)
  x86: Remove cmpxchg from i386 NMI nesting code
  x86: Save cr2 in NMI in case NMIs take a page fault
  x86/debug: Add KERN_ to bare printks, convert printks to pr_

perf/x86: Add a microcode revision check for SNB-PEBS

2012-07-05T19:55:57+00:00

Recent Intel microcode resolved the SNB-PEBS issues, so conditionally
enable PEBS on SNB hardware depending on the microcode revision.

Thanks to Stephane for figuring out the various microcode revisions.

Suggested-by: Stephane Eranian 
Acked-by: Borislav Petkov 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/n/tip-v3672ziwh9damwqwh1uz3krm@git.kernel.org
Signed-off-by: Ingo Molnar

x86, microcode: Make reload interface per system

2012-07-01T17:24:09+00:00

The reload interface should be per-system so that a full system ucode
reload happens (on each core) when doing

echo 1 > /sys/devices/system/cpu/microcode/reload

Move it to the cpu subsys directory instead of it being per-cpu.

Cc: Henrique de Moraes Holschuh 
Cc: Peter Zijlstra 
Signed-off-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1340280437-7718-3-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin

x86, microcode: Sanitize per-cpu microcode reloading interface

2012-07-01T17:24:05+00:00

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.

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

x86/microcode: Mark microcode_id[] as __initconst

2012-06-20T12:33:47+00:00

It's not being used for other than creating module aliases (i.e.
no loadable section has any reference to it).

Signed-off-by: Jan Beulich 
Link: http://lkml.kernel.org/r/4FDF1EFD020000780008A65D@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar

x86, microcode: microcode_core.c simple_strtoul cleanup

2012-05-07T18:36:49+00:00

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

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