.raSearchStart in the cases where there are alignment operators in
the program string.
If alignment operators are found in the program string, the current
value of %ebp must be valid and it is the only reliable data point
that can be used for getting to the previous frame. Previously, the
.raSearchStart calculation was based on %esp and when %esp is aligned
in the current frame (which is a lossy operation) the resulting
.raSearchStart cannot was incorrect. There is code that is trying to
work around this problem (scanning of up to 3 words for a return
address) which is unreliable and it doesn't work in many cases (e.g.
when the alignment is on a 64-byte boundary).
This fix is already deployed in Google and it was measured to reduce
the number of wrong stack traces (for Windows crashes) by 45%. No
regressions have been found so far.
Here is an example of an issue that was fixed by this change (where
register %esp is aligned on the 64-byte boundary and the workarounds
that we already had didn't work):
https://code.google.com/p/chromium/issues/detail?id=311359
0:013> uf chrome_59630000!base::MessagePumpForIO::DoRunLoop
518 59685c39 55 push ebp
518 59685c3a 8bec mov ebp,esp
518 59685c3c 83e4c0 and esp,0FFFFFFC0h <== 64-byte boundary
518 59685c3f 83ec34 sub esp,34h
518 59685c42 53 push ebx
518 59685c43 56 push esi
Program string contains 64-byte alignment:
$T1 .raSearch = $T0 $T1 4 - 64 @ = $ebp $T1 4 - ^ = $eip $T1 ^ =
$esp $T1 4 + = $20 $T0 56 - ^ = $23 $T0 60 - ^ = $24 $T0 64 - ^ =
Review URL: https://breakpad.appspot.com/694002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1232 4c0a9323-5329-0410-9bdc-e9ce6186880e
This is achieved by:
1. Extending the span of the scan for return address in the conext frame. Initially, I wanted to extend the span of the scan for all frames but then I noticed that there is code for ARM already that is extending the search only for the context frame. This kind of makes sense so I decided to reuse the same idea everywhere.
2. Attempting to restore the EBP chain after a successful scan for return address so that the stackwalker can switch back to FRAME_TRUST_CFI for the rest of the frames when possible.
I also fixed the lint errors in the files touched.
Review URL: https://breakpad.appspot.com/605002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1193 4c0a9323-5329-0410-9bdc-e9ce6186880e
do with FPO (frame-pointer-omission) optimized context
frames where the context frame represents a Windows
System call stub.
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@971 4c0a9323-5329-0410-9bdc-e9ce6186880e
Add a CFIFrameInfo class (named for symmetry with WindowsFrameInfo) to
represent the set of STACK CFI rules in effect at a given instruction,
and apply them to a set of register values. Provide a SimpleCFIWalker
class template, to allow the essential CFI code to be shared amongst
the different architectures.
Teach BasicSourceLineResolver to partially parse 'STACK CFI' records,
and produce the set of rules in effect at a given instruction on
demand, by combining the initial rule set and the appropriate rule
deltas in a CFIFrameInfo object.
Adapt StackwalkerX86 and StackFrameX86 to retrieve, store, and apply
CFI stack walking information.
Add validity flags for all the general-purpose registers to
StackFrameX86::ContextValidity.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@549 4c0a9323-5329-0410-9bdc-e9ce6186880e
We've gotten mixed advice from the lawyery types about whether this
matters. But it's easy enough to do.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@517 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch moves the code for finding caller frames using STACK WIN
data and the code to do so using the traditional frame layout (%ebp
points at saved %ebp, pushed just after return address) into their own
functions. In addition to making things a little clearer, this is
preparation for adding support for STACK CFI records into the mix.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@512 4c0a9323-5329-0410-9bdc-e9ce6186880e
The Google C++ Style Guide requires all parameters passed by reference
to be labeled 'const', and says that pointers should be used for
output arguments. This patch brings google_breakpad::StackwalkerX86
into line.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@510 4c0a9323-5329-0410-9bdc-e9ce6186880e
At the moment, StackwalkerX86::GetCallerFrame doesn't save the
WindowsFrameInfo that it finds for a frame unless it successfully
constructs the caller frame. This means that the windows_frame_info
field of the last frame on the stack is left unset, even when that
frame does have windows unwinding information.
This is not user-visible behavior, so it doesn't matter, but it is a
blemish on the interface, and unit tests (added in a later patch)
expect it.
This patch saves the information in the frame as soon as we find it.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@508 4c0a9323-5329-0410-9bdc-e9ce6186880e
At the moment, the StackWalker GetCallerFrame member function expects
a vector of WindowsFrameInfo structures, even though WindowsFrameInfo
is only used or useful on one one implementation (StackWalkerX86).
This patch changes StackWalker::GetCallerFrame to no longer expect the
WindowsFrameInfo structures, and changes all implementations to match.
In particular, StackWalkerX86 is changed to find the WindowsFrameInfo
data itself, and store a pointer to whatever it got in the StackFrame
object itself (which is really a StackFrameX86).
To allow GetCallerFrame implementations to look up stack walking data,
StackWalker::resolver_ needs to be made protected, not private.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@491 4c0a9323-5329-0410-9bdc-e9ce6186880e
Also, rename stack_frame_info.h to windows_frame_info.h.
If it seems odd to have functions like FillSourceLineInfo returning
Windows-specific data structures... well, it is! This patch just makes
it more obvious what's going on.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@471 4c0a9323-5329-0410-9bdc-e9ce6186880e
- Introduces a standard API for dealing with modules. MinidumpModule
is now a concrete implementation of this API. Code may interact with
single modules using the CodeModule interface, and collections of
modules using its container, the CodeModules interface.
- CodeModule is used directly by SymbolSupplier implementations and
SourceLineResolver. Reliance on the specific implementation in
MinidumpModule has been eliminated.
- Module lists are now added to ProcessState objects. Module references
in each stack frame are now pointers to objects in these module lists.
- The sample minidump_stackwalk tool prints the module list after printing
all threads' stacks.
http://groups.google.com/group/airbag-dev/browse_frm/thread/a9c0550edde54cf8
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@74 4c0a9323-5329-0410-9bdc-e9ce6186880e
- minidump_stackwalk is now much more useful as a debugging tool and
even as a standalone tool.
- Reimplementation of minidump_stackwalk around MinidumpProcessor.
- minidump_stackwalk displays all pertinent information returned by
MinidumpProcessor in the ProcessState.
- New PathnameStripper::File static utility method to display only the
leaf file name in a pathname, cleaning up minidump_stackwalk's output.
- New SimpleSymbolSupplier class, which implements a simple
filesystem-based symbol supplier compatible with the layout used by
Microsoft Symbol Server and its client cache.
- minidump_stackwalk now accepts an optional second argument, a pathname
to use as a symbol directory for a SimpleSymbolSupplier.
- Updated test data to be compatible with SimpleSymbolSupplier, and added
test data for kernel32.pdb. Test data converted from CRLF line endings
to LF.
http://groups.google.com/group/airbag-dev/browse_thread/thread/cce30a84f6b2d728
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@53 4c0a9323-5329-0410-9bdc-e9ce6186880e
caller-implemented SymbolSupplier object to get a symbol file.
Add a CrashReportProcessor object which provides a simple API for processing
a CrashReport struct, given a SymbolSupplier and a minidump file.
r=mmentovai (#17))
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@18 4c0a9323-5329-0410-9bdc-e9ce6186880e
- In class definitions, one-space indent for public/protected/private.
- Multi-line initializer format puts comma at end of line.
Also:
- Eliminate the long list of friends in Minidump by making swap() public.
(People who need to access unknown stream types directly will need
access to swap() too.)
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@16 4c0a9323-5329-0410-9bdc-e9ce6186880e
