History log of /arch/x86/kernel/cpu/mcheck/mce-severity.c
Revision Date Author Comments
e6b2a258ab83555e062cd2bc2a0ade31b8c118d1 23-May-2012 Tony Luck <tony.luck@intel.com> x86/mce: Fix check for processor context when machine check was taken.

commit 875e26648cf9b6db9d8dc07b7959d7c61fb3f49c upstream.

Linus pointed out that there was no value is checking whether m->ip
was zero - because zero is a legimate value. If we have a reliable
(or faked in the VM86 case) "m->cs" we can use it to tell whether we
were in user mode or kernelwhen the machine check hit.

Reported-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
08dda402d60a721ac94e79efd7646b332be3e3b2 27-Jan-2012 Tony Luck <tony.luck@intel.com> x86/mce: Replace hard coded hex constants with symbolic defines

Magic constants like 0x0134 in code just invite questions on
where they come from, what they mean, can they be changed.

Provide #defines for the architecturally defined MCACOD values
with a reference to the Intel Software Developers manual which
describes them.

Signed-off-by: Tony Luck <tony.luck@intel.com>
5f7b88d51e89771f64c15903b96b5933dd0bc6d8 03-Jan-2012 Tony Luck <tony.luck@intel.com> x86/mce: Recognise machine check bank signature for data path error

Action required data path signature is defined in table 15-19 of SDM:

+-----------------------------------------------------------------------------+
| SRAR Error | Valid | OVER | UC | EN | MISCV | ADDRV | PCC | S | AR | MCACOD |
| Data Load | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0x134 |
+-----------------------------------------------------------------------------+

Recognise this, and pass MCE_AR_SEVERITY code back to do_machine_check() if
we have the action handler configured (CONFIG_MEMORY_FAILURE=y)

Acked-by: Borislav Petkov <bp@amd64.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
7639bfc753f70321dbea83852e1cc47a45b681d7 08-Jun-2011 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> x86, mce, severity: Clean up trivial coding style problems

More specifically:

- sort bits in the macros
- use BITCLR/BITSET
- coordinate message pattern
- use m for struct mce
- cleanup for severities_debugfs_init()

No functional change.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/4DEED679.9090503@jp.fujitsu.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
a17957cdec69acb9e26319618b95a810a936e637 08-Jun-2011 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> x86, mce, severity: Cleanup severity table

The current format of an item in this table is:
condition(param, ..., level, message [, condition2 ...])

So we have to check both an item's head and tail to find the conditions
which match the item.

Format them in a more straight forward manner:
item(level, message, condition [, condition2 ...])

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/4DEED61F.5010502@jp.fujitsu.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
901d7691d3238ad68c80a567b88b1e5d614137fb 08-Jun-2011 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> x86, mce, severity: Make formatting a bit more readable

The table looks very complicated and hard to read for people other than
skilled developers. So let's clean it up a bit. At first, change format
to ease reading elements in the table.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/4DEED5EB.6050400@jp.fujitsu.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
880a317abccf60b989951bf1515964cd73245970 08-Jun-2011 Tony Luck <tony.luck@intel.com> x86, mce, severity: Fix two severities table signatures

The "Spurious not enabled" entry is redundant: the "Not enabled" entry
earlier in the table will cover this case.

The "Action required; unknown MCACOD" entry shouldn't specify MCACOD in
the .mask field. Current code will only match for mcacod==0 rather than
all AR=1 entries.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/4DEED5BC.8030703@jp.fujitsu.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
6038f373a3dc1f1c26496e60b6c40b164716f07e 15-Aug-2010 Arnd Bergmann <arnd@arndb.de> llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
e34e77ce348feac3c8c607774efb1f8a9262127d 14-Sep-2009 Andi Kleen <ak@linux.intel.com> x86, mce: Fix compilation with !CONFIG_DEBUG_FS in mce-severity.c

Fix compilation error in arch/x86/kernel/cpu/mcheck/mce-severity.c
when CONFIG_DEBUG_FS is disabled, introduced in commit
5be9ed251f58881dfc3dd6742a81ff9ad1a7bb04.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
5be9ed251f58881dfc3dd6742a81ff9ad1a7bb04 31-Jul-2009 Huang Ying <ying.huang@intel.com> x86, mce: Move debugfs mce dir creating to mce.c

Because more debugfs files under mce dir will be create in mce.c.

ChangeLog:

v5:

- Rebased on x86-tip.git/mce

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
d0c87d1f61704ed589fc0788bedd753632340e98 28-Jul-2009 Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> x86, mce: remove never executed code

fseverities_coverage is never NULL in err_out code path.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
4611a6fa4b37cf6b8b6066ed0d605c994c62a1a0 27-May-2009 Huang Ying <ying.huang@intel.com> x86, mce: export MCE severities coverage via debugfs

The MCE severity judgement code is data-driven, so code coverage tools
such as gcov can not be used for measuring coverage. Instead a dedicated
coverage mechanism is implemented. The kernel keeps track of rules
executed and reports them in debugfs.

This is useful for increasing coverage of the mce-test testsuite.

Right now it's unconditionally enabled because it's very little code.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
ed7290d0ee8f81aa78bfe816f01b012f208cafc5 27-May-2009 Andi Kleen <andi@firstfloor.org> x86, mce: implement new status bits

The x86 architecture recently added some new machine check status bits:
S(ignalled) and AR (Action-Required). Signalled allows to check
if a specific event caused an exception or was just logged through CMCI.
AR allows the kernel to decide if an event needs immediate action
or can be delayed or ignored.

Implement support for these new status bits. mce_severity() uses
the new bits to grade the machine check correctly and decide what
to do. The exception handler uses AR to decide to kill or not.
The S bit is used to separate events between the poll/CMCI handler
and the exception handler.

Classical UC always leads to panic. That was true before anyways
because the existing CPUs always passed a PCC with it.

Also corrects the rules whether to kill in user or kernel context
and how to handle missing RIPV.

The machine check handler largely uses the mce-severity grading
engine now instead of making its own decisions. This means the logic
is centralized in one place. This is useful because it has to be
evaluated multiple times.

v2: Some rule fixes; Add AO events
Fix RIPV, RIPV|EIPV order (Ying Huang)
Fix UCNA with AR=1 message (Ying Huang)
Add comment about panicing in m_c_p.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
817f32d02a52dd7f5941534e0699883691e918df 27-May-2009 Andi Kleen <andi@firstfloor.org> x86, mce: add table driven machine check grading

The machine check grading (as in deciding what should be done for a given
register value) has to be done multiple times soon and it's also getting
more complicated.
So it makes sense to consolidate it into a single function. To get smaller
and more straight forward and possibly more extensible code I opted towards
a new table driven method. The various rules are put into a table
when is then executed by a very simple interpreter.

The grading engine is in a new file mce-severity.c. I also added a private
include file mce-internal.h, because mce.h is already a bit too cluttered.

This is dead code right now, but will be used in followon patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>