Impact: fix deadlock
This is in response to the following bug report:
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12100
Subject : resume (S2R) broken by Intel microcode module, on A110L
Submitter : Andreas Mohr <andi@lisas.de>
Date : 2008-11-25 08:48 (19 days old)
Handled-By : Dmitry Adamushko <dmitry.adamushko@gmail.com>
[ The deadlock scenario has been discovered by Andreas Mohr ]
I think I might have a logical explanation why the system:
(http://bugzilla.kernel.org/show_bug.cgi?id=12100)
might hang upon resuming, OTOH it should have likely hanged each and every time.
(1) possible deadlock in microcode_resume_cpu() if either 'if' section is
taken;
(2) now, I don't see it in spec. and can't experimentally verify it (newer
ucodes don't seem to be available for my Core2duo)... but logically-wise, I'd
think that when read upon resuming, the 'microcode revision' (MSR 0x8B) should
be back to its original one (we need to reload ucode anyway so it doesn't seem
logical if a cpu doesn't drop the version)... if so, the comparison with
memcmp() for the full 'struct cpu_signature' is wrong... and that's how one of
the aforementioned 'if' sections might have been triggered - leading to a
deadlock.
Obviously, in my tests I simulated loading/resuming with the ucode of the same
version (just to see that the file is loaded/re-loaded upon resuming) so this
issue has never popped up.
I'd appreciate if someone with an appropriate system might give a try to the
2nd patch (titled "fix a comparison && deadlock...").
In any case, the deadlock situation is a must-have fix.
Reported-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Tested-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: make global variables and a function static
Fix following sparse warnings:
arch/x86/kernel/microcode_core.c:102:22: warning: symbol
'microcode_ops' was not declared. Should it be static?
arch/x86/kernel/microcode_core.c:206:24: warning: symbol
'microcode_pdev' was not declared. Should it be static?
arch/x86/kernel/microcode_core.c:322:6: warning: symbol
'microcode_update_cpu' was not declared. Should it be static?
arch/x86/kernel/microcode_intel.c:468:22: warning: symbol
'microcode_intel_ops' was not declared. Should it be static?
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Combine both generic and arch-specific parts of microcode into a
single module (arch-specific parts are config-dependent).
Also while we are at it, move arch-specific parts from microcode.h
into their respective arch-specific .c files.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: "Peter Oruba" <peter.oruba@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
this is a rework of the microcode splitup in tip/x86/microcode
(1) I think this new interface is cleaner (look at the changes
in 'struct microcode_ops' in microcode.h);
(2) it's -64 lines of code;
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is the 1st patch in the series. Here the aim was to avoid any
significant changes, logically-wise.
So it's mainly about generic interface refactoring: e.g. make
microcode_{intel,amd}.c more about arch-specific details and less
about policies like make-sure-we-run-on-a-target-cpu
(no more set_cpus_allowed_ptr() here) and generic synchronization (no
more microcode_mutex here).
All in all, more line have been deleted than added.
4 files changed, 145 insertions(+), 198 deletions(-)
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Don't use get_cpu() at all. Resort to checking a boot-up CPU (#0) in
microcode_{intel,amd}_module_init().
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The microcode stores its date in a uint32_t in some weird order
approximating pdp-endian. Rather than printing it like that, print it
properly in ISO standard form.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Refactored code by introducing a two-module solution.
There is one general module in which vendor specific modules can hook into.
However, that is exclusive, there is only one vendor specific module
allowed at a time. A CPU vendor check makes sure only the correct
module for the underlying system gets called.
Functinally in terms of patch loading itself there are no changes. This
refactoring provides a basis for future implementations of other vendors'
patch loaders.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Renamed common structures to vendor specific naming scheme
so other vendors will be able to use the same naming
convention.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Split off existing code into two seperate files. One file holds general
code, the other file vendor specific parts.
No functional changes, only refactoring.
Temporarily Introduced a new module name 'ucode' for result,
due to already taken name 'microcode'.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This structure will be later used by other modules as well and
needs therfore to be moved out to a header file.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Removed typedefs. No functional changes to the code.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Intel specific microcode declarations have been moved to a seperate header file.
There are no code changes to the code itself and no side effects to other parts.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Replace previous instances of the cpumask_of_cpu_ptr* macros
with a the new (lvalue capable) generic cpumask_of_cpu().
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.
I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.
I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.
Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* This patch replaces the dangerous lvalue version of cpumask_of_cpu
with new cpumask_of_cpu_ptr macros. These are patterned after the
node_to_cpumask_ptr macros.
In general terms, if there is a cpumask_of_cpu_map[] then a pointer to
the cpumask_of_cpu_map[cpu] entry is used. The cpumask_of_cpu_map
is provided when there is a large NR_CPUS count, reducing
greatly the amount of code generated and stack space used for
cpumask_of_cpu(). The pointer to the cpumask_t value is needed for
calling set_cpus_allowed_ptr() to reduce the amount of stack space
needed to pass the cpumask_t value.
If there isn't a cpumask_of_cpu_map[], then a temporary variable is
declared and filled in with value from cpumask_of_cpu(cpu) as well as
a pointer variable pointing to this temporary variable. Afterwards,
the pointer is used to reference the cpumask value. The compiler
will optimize out the extra dereference through the pointer as well
as the stack space used for the pointer, resulting in identical code.
A good example of the orthogonal usages is in net/sunrpc/svc.c:
case SVC_POOL_PERCPU:
{
unsigned int cpu = m->pool_to[pidx];
cpumask_of_cpu_ptr(cpumask, cpu);
*oldmask = current->cpus_allowed;
set_cpus_allowed_ptr(current, cpumask);
return 1;
}
case SVC_POOL_PERNODE:
{
unsigned int node = m->pool_to[pidx];
node_to_cpumask_ptr(nodecpumask, node);
*oldmask = current->cpus_allowed;
set_cpus_allowed_ptr(current, nodecpumask);
return 1;
}
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
First announce ourself, then start working. Currently this module reports
itself when all is completed which is not most modules do. Plus some
cosmetic/whitespace cleanups.
Signed-off-by: Ben Castricum <lk0806@bencastricum.nl>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Use new set_cpus_allowed_ptr() function added by previous patch,
which instead of passing the "newly allowed cpus" cpumask_t arg
by value, pass it by pointer:
-int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
+int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
* Cleanup uses of CPU_MASK_ALL.
* Collapse other NR_CPUS changes to arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
Use pointers to cpumask_t arguments whenever possible.
Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function
Cc: Len Brown <len.brown@intel.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Report when microcode was successfully updated. It used to be there but
now with DEBUG unset it becomes very silent. Also some cosmetic fixes.
Signed-off-by: Ben Castricum <lk08@bencastricum.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix the following warnings:
WARNING: arch/x86/kernel/built-in.o(.exit.text+0xf8): Section mismatch in reference from the function msr_exit() to the variable .cpuinit.data:msr_class_cpu_notifier
WARNING: arch/x86/kernel/built-in.o(.exit.text+0x158): Section mismatch in reference from the function cpuid_exit() to the variable .cpuinit.data:cpuid_class_cpu_notifier
WARNING: arch/x86/kernel/built-in.o(.exit.text+0x171): Section mismatch in reference from the function microcode_exit() to the variable .cpuinit.data:mc_cpu_notifier
In all three cases there were a function annotated __exit
that referenced a variable annotated __cpuinitdata.
The fix was to replace the annotation of the notifier
with __refdata to tell modpost that the reference to
a _cpuinit function in the notifier are OK.
The unregister call that references the notifier
variable will simple delete the function pointer
so there is no problem ignoring the reference.
Note: This looks like another case where __cpuinit
has been used as replacement for proper use
of CONFIG_HOTPLUG_CPU to decide what code are used for
HOTPLUG_CPU.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Replace all lock_cpu_hotplug/unlock_cpu_hotplug from the kernel and use
get_online_cpus and put_online_cpus instead as it highlights the
refcount semantics in these operations.
The new API guarantees protection against the cpu-hotplug operation, but
it doesn't guarantee serialized access to any of the local data
structures. Hence the changes needs to be reviewed.
In case of pseries_add_processor/pseries_remove_processor, use
cpu_maps_update_begin()/cpu_maps_update_done() as we're modifying the
cpu_present_map there.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cpu_data is currently an array defined using NR_CPUS. This means that
we overallocate since we will rarely really use maximum configured cpus.
When NR_CPU count is raised to 4096 the size of cpu_data becomes
3,145,728 bytes.
These changes were adopted from the sparc64 (and ia64) code. An
additional field was added to cpuinfo_x86 to be a non-ambiguous cpu
index. This corresponds to the index into a cpumask_t as well as the
per_cpu index. It's used in various places like show_cpuinfo().
cpu_data is defined to be the boot_cpu_data structure for the NON-SMP
case.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fix the following section mismatch warnings in microcode.c:
WARNING: arch/i386/kernel/built-in.o(.init.text+0x3966): Section mismatch: reference to .exit.text: (between 'microcode_init' and 'parse_maxcpus')
WARNING: arch/i386/kernel/built-in.o(.init.text+0x3992): Section mismatch: reference to .exit.text: (between 'microcode_init' and 'parse_maxcpus')
The warning are caused by a function marked __init that
calls a function marked __exit.
Functions marked __exit may be discarded either during link or run-time
and thus the reference is not good.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the microcode driver use the suspend-related CPU hotplug notifications
to handle the CPU hotplug events occuring during system-wide suspend and
resume transitions. Remove the global variable suspend_cpu_hotplug
previously used for this purpose.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress. This
patch introduces such notifications and causes them to be used during
suspend and resume transitions. It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).
[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the regression resulting from the recent change of suspend code
ordering that causes systems based on Intel x86 CPUs using the microcode
driver to hang during the resume.
The problem occurs since the microcode driver uses request_firmware() in
its CPU hotplug notifier, which is called after tasks has been frozen and
hangs. It can be fixed by telling the microcode driver to use the
microcode stored in memory during the resume instead of trying to load it
from disk.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Adrian Bunk <bunk@stusta.de>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maxim <maximlevitsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix bogus gcc warning
linux/arch/i386/kernel/microcode.c:387: warning: ‘new_mc’ may be used uninitialized in this function
Signed-off-by: Andi Kleen <ak@suse.de>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
[akpm@osdl.org: sparc64 fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As Adrian pointed out recently, there were still a couple of places where
I should have fixed my email address.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There was lots of #ifdef noise in the kernel due to hotcpu_notifier(fn,
prio) not correctly marking 'fn' as used in the !HOTPLUG_CPU case, and thus
generating compiler warnings of unused symbols, hence forcing people to add
#ifdefs.
the compiler can skip truly unused functions just fine:
text data bss dec hex filename
1624412 728710 3674856 6027978 5bfaca vmlinux.before
1624412 728710 3674856 6027978 5bfaca vmlinux.after
[akpm@osdl.org: topology.c fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If the microcode driver is built in (rather than module) there are some,
ehm, interesting effects happening due to the new "call out to userspace"
behavior that is introduced.. and which runs too early. The result is a
boot hang; which is really nasty.
The patch below is a minimally safe patch to fix this regression for 2.6.19
by just not requesting actual microcode updates during early boot. (That
is a good idea in general anyway)
The "real" fix is a lot more complex given the entire cpu hotplug scenario
(during cpu hotplug you normally need to load the microcode as well); but
the interactions for that are just really messy at this point; this fix at
least makes it work and avoids a full detangle of hotplug.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
IA32 manual says if micorcode update's size is 0, then the size is
default size (2048 bytes). But this doesn't suggest all microcode
update's size should be above 2048 bytes to me. We actually had a
microcode update whose size is 1024 bytes. The patch just removed the
check.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Tigran Aivazian <tigran@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add sysfs support. Currently each CPU has three microcode related
attributes. One is 'version' which shows current ucode version of CPU.
Tools can use the attribute do validation or show CPU ucode status. one is
'reload' which allows manually reloading ucode. Another is
'processor_flags', which exports processor flags, so we can write tools to
check if CPU has latest ucode. Also add suspend/resume and CPU hotplug
support.
[akpm@osdl.org: cleanups, build fix]
[bunk@stusta.de: Kconfig fixes]
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Tigran Aivazian <tigran@veritas.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Using request_firmware to pull ucode from userspace, so we don't need the
application 'microcode_ctl' to assist. We name each ucode file according
to CPU's info as intel-ucode/family-model-stepping. In this way we could
split ucode file as small one. This has a lot of advantages such as
selectively update and validate microcode for specific models, better
manage microcode file, easily write tools for administerators and so on.
with the changes, we should put all intel-ucode/xx-xx-xx microcode files
into the firmware dir (I had a tool to split previous big data file into
small one and later we will release new style data file). The init script
should be changed to just loading the driver without unloading
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Tigran Aivazian <tigran@veritas.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clean up microcode update driver and make it more readable.
[akpm@osdl.org: cleanups]
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Tigran Aivazian <tigran@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When multiple updates matching a given CPU are found in the update file, the
action taken by the microcode update driver was inappropriate:
- when lower revision microcode was found before matching or higher revision
one, the driver would needlessly complain that it would not downgrade the
CPU
- when microcode matching the currently installed revision was found before
newer revision code, no update would actually take place
To change this behavior, the driver now concludes about possibly updates and
issues messages only when the entire input was parsed.
Additionally, this adds back (in different places, and conditionalized upon
a new module option) some messages removed by a previous patch.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: Tigran Aivazian <tigran_aivazian@symantec.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Nowadays, even Debian stable ships a microcode_ctl utility recent enough to no
longer use this ioctl.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Tigran Aivazian <tigran_aivazian@symantec.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ingo Molnar