The various stack tracing routines take a 'bp' argument in which the
caller is supposed to provide the base pointer to use, or 0 if doesn't
have one. Since bp is garbage whenever CONFIG_FRAME_POINTER is not
defined, this means all callers in principle should either always pass
0, or be conditional on CONFIG_FRAME_POINTER.
However, there are only really three use cases for stack tracing:
(a) Trace the current task, including IRQ stack if any
(b) Trace the current task, but skip IRQ stack
(c) Trace some other task
In all cases, if CONFIG_FRAME_POINTER is not defined, bp should just
be 0. If it _is_ defined, then
- in case (a) bp should be gotten directly from the CPU's register, so
the caller should pass NULL for regs,
- in case (b) the caller should should pass the IRQ registers to
dump_trace(),
- in case (c) bp should be gotten from the top of the task's stack, so
the caller should pass NULL for regs.
Hence, the bp argument is not necessary because the combination of
task and regs is sufficient to determine an appropriate value for bp.
This patch introduces a new inline function stack_frame(task, regs)
that computes the desired bp. This function is then called from the
two versions of dump_stack().
Signed-off-by: Soren Sandmann <ssp@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@infradead.org>,
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>,
LKML-Reference: <m3oc9rop28.fsf@dhcp-100-3-82.bos.redhat.com>>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86-32, percpu: Correct the ordering of the percpu readmostly section
x86, mm: Enable ARCH_DMA_ADDR_T_64BIT with X86_64 || HIGHMEM64G
x86: Spread tlb flush vector between nodes
percpu: Introduce a read-mostly percpu API
x86, mm: Fix incorrect data type in vmalloc_sync_all()
x86, mm: Hold mm->page_table_lock while doing vmalloc_sync
x86, mm: Fix bogus whitespace in sync_global_pgds()
x86-32: Fix sparse warning for the __PHYSICAL_MASK calculation
x86, mm: Add RESERVE_BRK_ARRAY() helper
mm, x86: Saving vmcore with non-lazy freeing of vmas
x86, kdump: Change copy_oldmem_page() to use cached addressing
x86, mm: fix uninitialized addr in kernel_physical_mapping_init()
x86, kmemcheck: Remove double test
x86, mm: Make spurious_fault check explicitly check the PRESENT bit
x86-64, mem: Update all PGDs for direct mapping and vmemmap mapping changes
x86, mm: Separate x86_64 vmalloc_sync_all() into separate functions
x86, mm: Avoid unnecessary TLB flush
In x86, faults exit by executing the iret instruction, which then
reenables NMIs if we faulted in NMI context. Then if a fault
happens in NMI, another NMI can nest after the fault exits.
But we don't yet support nested NMIs because we have only one NMI
stack. To prevent from that, check that vmalloc and kmemcheck
faults don't happen in this context. Most of the other kernel faults
in NMIs can be more easily spotted by finding explicit
copy_from,to_user() calls on review.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
The opcodes 0x2e and 0x3e are tested for in the first Group 2
line as well.
The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@expression@
expression E;
@@
(
* E
|| ... || E
|
* E
&& ... && E
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
LKML-Reference: <1283010066-20935-5-git-send-email-julia@diku.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is a fix for bug #14845 (bugzilla.kernel.org). The update_checksum()
function in mm/kmemleak.c calls kmemcheck_is_obj_initialised() before scanning
an object. When KMEMCHECK_PARTIAL_OK is enabled, this function returns true.
However, the crc32_le() reads smaller intervals (32-bit) for which
kmemleak_is_obj_initialised() may be false leading to a kmemcheck warning.
Note that kmemcheck_is_obj_initialized() is currently only used by
kmemleak before scanning a memory location.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian Casteyde <casteyde.christian@free.fr>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
As suggested by Vegard Nossum, use KERN_WARNING for error
reporting to make sure kmemcheck reports end up in syslog.
Suggested-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1261990935.4641.7.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix the following 'make includecheck' warning:
arch/x86/mm/kmemcheck/shadow.c: linux/module.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <1247065179.4382.51.camel@ht.satnam>
Ingo Molnar reported the following kmemcheck warning when running both
kmemleak and kmemcheck enabled:
PM: Adding info for No Bus:vcsa7
WARNING: kmemcheck: Caught 32-bit read from uninitialized memory
(f6f6e1a4)
d873f9f600000000c42ae4c1005c87f70000000070665f666978656400000000
i i i i u u u u i i i i i i i i i i i i i i i i i i i i i u u u
^
Pid: 3091, comm: kmemleak Not tainted (2.6.31-rc7-tip #1303) P4DC6
EIP: 0060:[<c110301f>] EFLAGS: 00010006 CPU: 0
EIP is at scan_block+0x3f/0xe0
EAX: f40bd700 EBX: f40bd780 ECX: f16b46c0 EDX: 00000001
ESI: f6f6e1a4 EDI: 00000000 EBP: f10f3f4c ESP: c2605fcc
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: e89a4844 CR3: 30ff1000 CR4: 000006f0
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff4ff0 DR7: 00000400
[<c110313c>] scan_object+0x7c/0xf0
[<c1103389>] kmemleak_scan+0x1d9/0x400
[<c1103a3c>] kmemleak_scan_thread+0x4c/0xb0
[<c10819d4>] kthread+0x74/0x80
[<c10257db>] kernel_thread_helper+0x7/0x3c
[<ffffffff>] 0xffffffff
kmemleak: 515 new suspected memory leaks (see
/sys/kernel/debug/kmemleak)
kmemleak: 42 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
The problem here is that kmemleak will scan partially initialized
objects that makes kmemcheck complain. Fix that up by skipping
uninitialized memory regions when kmemcheck is enabled.
Reported-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
This check is a left-over from ancient times. We now have the equivalent
check much earlier in both the page fault handler and the debug trap
handler (the calls to kmemcheck_active()).
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>