Commit Graph

9 Commits

Author SHA1 Message Date
Vegard Nossum ac61a75796 kmemcheck: add opcode self-testing at boot
We've had some troubles in the past with weird instructions. This
patch adds a self-test framework which can be used to verify that
a certain set of opcodes are decoded correctly. Of course, the
opcodes which are not tested can still give the wrong results.

In short, this is just a safeguard to catch unintentional changes
in the opcode decoder. It does not mean that errors can't still
occur!

[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 15:49:22 +02:00
Vegard Nossum b1eeab6768 kmemcheck: add hooks for the page allocator
This adds support for tracking the initializedness of memory that
was allocated with the page allocator. Highmem requests are not
tracked.

Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>

[build fix for !CONFIG_KMEMCHECK]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 15:48:33 +02:00
Pekka Enberg f8b4ece2a9 kmemcheck: use kmemcheck_pte_lookup() instead of open-coding it
Lets use kmemcheck_pte_lookup() in kmemcheck_fault() instead of
open-coding it there.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 12:40:00 +02:00
Pekka Enberg 6d9609c132 kmemcheck: move 64-bit ifdef out of kmemcheck_opcode_decode()
This patch moves the CONFIG_X86_64 ifdef out of kmemcheck_opcode_decode() by
introducing a version of the function that always returns false for
CONFIG_X86_32.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 12:39:59 +02:00
Pekka Enberg 0c33cacd86 kmemcheck: remove multiple ifdef'd definitions of the same global variable
Multiple ifdef'd definitions of the same global variable is ugly and
error-prone. Fix that up.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 12:39:57 +02:00
Pekka Enberg 5b53b76a61 kmemcheck: make initialization message less confusing
The "Bugs, beware!" printout during is cute but confuses users that something
bad happened so change the text to the more boring "Initialized" message.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 12:39:56 +02:00
Pekka Enberg 6a19638719 kmemcheck: remove forward declarations from error.c
This patch reorders code in error.c so that we can get rid of the forward
declarations.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15 12:39:47 +02:00
Randy Dunlap 60e383931d kmemcheck: include module.h to prevent warnings
kmemcheck/shadow.c needs to include <linux/module.h> to prevent
the following warnings:

linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : data definition has no type or storage class
linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : parameter names (without types) in function declaration

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: vegardno@ifi.uio.no
Cc: penberg@cs.helsinki.fi
Cc: akpm <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-13 15:37:49 +02:00
Vegard Nossum dfec072ecd kmemcheck: add the kmemcheck core
General description: kmemcheck is a patch to the linux kernel that
detects use of uninitialized memory. It does this by trapping every
read and write to memory that was allocated dynamically (e.g. using
kmalloc()). If a memory address is read that has not previously been
written to, a message is printed to the kernel log.

Thanks to Andi Kleen for the set_memory_4k() solution.

Andrew Morton suggested documenting the shadow member of struct page.

Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

[export kmemcheck_mark_initialized]
[build fix for setup_max_cpus]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
2009-06-13 15:37:30 +02:00