Commit Graph

412 Commits

Author SHA1 Message Date
Kazu Hirata 343523d040 [lldb] Use std::nullopt instead of None (NFC)
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-04 16:51:25 -08:00
Pavel Labath 3427cb5b3a [lldb] Prevent an infinite loop while reading memory regions
A malformed qMemoryRegionInfo response can easily trigger an infinite
loop if regions end (base + size) wraps the address space. A
particularly interesting is the case where base+size=0, which a stub
could use to say that the rest of the memory space is unmapped, even
though lldb expects 0xff... in this case.

One could argue which behavior is more correct (technically, the
current behavior does not say anything about the last byte), but unless
we stop using 0xff... to mean "invalid address", that discussion is very
academic. This patch truncates address ranges which wraps the address
space, which handles the zero case as well as other kinds of malformed
packets.
2022-11-25 11:55:41 +01:00
Pavel Labath 8d1de7b34a [lldb/gdb-server] Better reporting of launch errors
Use our "rich error" facility to propagate error reported by the stub to
the user. lldb-server reports rich launch errors as of D133352.

To make this easier to implement, and reduce code duplication, I have
moved the vRun/A/qLaunchSuccess handling into a single
GDBRemoteCommunicationClient function.

Differential Revision: https://reviews.llvm.org/D134754
2022-10-06 17:18:51 +02:00
Jason Molenda 1a608cfb5c Recognize a platform binary in ProcessGDBRemote which determines plugins
Complete support of the binary-addresses key in the qProcessInfo packet
in ProcessGDBRemote, for detecting if one of the binaries needs to be
handled by a Platform plugin, and can be used to set the Process'
DynamicLoader plugin and the Target's Platform plugin.

Implement this method in PlatformDarwinKernel to recognize a kernel
fileset at that address, find the actual kernel address in the
fileset, set DynamicLoaderDarwinKernel and PlatformDarwinKernel
in the Process/Target; register the kernel address with the dynamic
loader so it will be loaded later during attach.

This patch only addresses the live debug scenario with a gdb remote
serial protocol connection. I'll handle corefiles in a subsequent
patch that builds on this.

Differential Revision: https://reviews.llvm.org/D133534
rdar://98754861
2022-09-09 14:57:08 -07:00
Michał Górny bdb4468d39 [gdb-remote] Move broadcasting logic down to GDBRemoteClientBase
Move the broadcasting support from GDBRemoteCommunication
to GDBRemoteClientBase since this is where it is actually used.  Remove
GDBRemoteCommunication and subclass constructor arguments left over
after Communication cleanup.

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D133427
2022-09-09 17:13:08 +02:00
Michał Górny 2f50883c13 [lldb] [gdb-remote] Include PID in vCont packets if multiprocess
Try to always send vCont packets and include the PID in them if running
multiprocess.  This is necessary to ensure that with the upcoming full
multiprocess support always resumes the correct process without having
to resort to the legacy Hc packets.

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D131758
2022-08-20 08:21:32 +02:00
Michael Buch 5517401f93 Revert "[lldb] [gdb-remote] Include PID in vCont packets if multiprocess"
This reverts commit ccb9d4d4ad.

https://reviews.llvm.org/D131758

Differential Revision: https://reviews.llvm.org/D132250
2022-08-19 18:05:41 +01:00
Michał Górny ccb9d4d4ad [lldb] [gdb-remote] Include PID in vCont packets if multiprocess
Try to always send vCont packets and include the PID in them if running
multiprocess.  This is necessary to ensure that with the upcoming full
multiprocess support always resumes the correct process without having
to resort to the legacy Hc packets.

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D131758
2022-08-19 09:02:20 +02:00
Fangrui Song 59d2495fe2 [lldb] LLVM_FALLTHROUGH => [[fallthrough]]. NFC 2022-08-08 11:31:49 -07:00
Slava Gurevich 5a906b70c1 [LLDB][NFC] Fix potential div by 0 "count" can be zero potentially causing div by 0
Differential Revision: https://reviews.llvm.org/D130939
2022-08-03 16:08:18 -07:00
Jason Molenda 96d12187b3 Allow firmware binaries to be specified only by load address
Add support to Mach-O corefiles and to live gdb remote serial protocol
connections for the corefile/remote stub to provide a list of load
addresses of binaries that should be found & loaded by lldb, and nothing
else.  lldb will try to parse the binary out of memory, and if it can
find a UUID, try to find a binary & its debug information based on the
UUID, falling back to using the memory image if it must.

A bit of code unification from three parts of lldb that were loading
individual binaries already, so there is a shared method in
DynamicLoader to handle all of the variations they were doing.

Re-landing this with a uuid_is_null() implementation added to
Utility/UuidCompatibility.h for non-Darwin systems.

Differential Revision: https://reviews.llvm.org/D130813
rdar://94249937
rdar://94249384
2022-08-02 14:14:16 -07:00
Jason Molenda 803386da2f Revert "Allow firmware binaries to be specified only by load address"
This reverts commit d8879fba88.

Debian bot failure; I included <uuid/uuid.h> to get uuid_is_null() but
don't get it there.  Will memcmp or whatever & recommit.
2022-08-02 13:53:34 -07:00
Jason Molenda d8879fba88 Allow firmware binaries to be specified only by load address
Add support to Mach-O corefiles and to live gdb remote serial protocol
connections for the corefile/remote stub to provide a list of load
addresses of binaries that should be found & loaded by lldb, and nothing
else.  lldb will try to parse the binary out of memory, and if it can
find a UUID, try to find a binary & its debug information based on the
UUID, falling back to using the memory image if it must.

A bit of code unification from three parts of lldb that were loading
individual binaries already, so there is a shared method in
DynamicLoader to handle all of the variations they were doing.

Differential Revision: https://reviews.llvm.org/D130813
rdar://94249937
rdar://94249384
2022-08-02 13:49:30 -07:00
Michał Górny 8068751189 [lldb] [gdb-remote] Refactor killing process and move it to client
Refactor the code responsible for sending the "k" packet and move it
into GDBRemoteCommunicationClient::KillProcess() method.  This is part
of refactoring to enable multiprocess support in the client,
and to support using the vKill packet instead.

As part of the refactoring, the following functional changes apply:

- Some redundant logging has been removed, as any failures are returned
  via exit_string anyway.

- SetLastStopPacket() is no longer called.  It is used only to populate
  the thread list, and since the process has just exited and we're
  terminating the process instance, there's really no reason to set it.

- On successful kill, exit_string is set to "killed", to clearly
  indicate that the process has terminated on our request rather than
  on its own.

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D130340
2022-07-25 18:43:32 +02:00
Kazu Hirata e5f568a49f Use has_value instead of hasValue (NFC) 2022-07-13 01:58:03 -07:00
Kazu Hirata 96d1b4ddb2 [lld] Don't use Optional::hasValue (NFC)
This patch replaces x.hasValue() with x where x is contextually
convertible to bool.
2022-06-26 19:29:40 -07:00
Kazu Hirata 3b7c3a654c Revert "Don't use Optional::hasValue (NFC)"
This reverts commit aa8feeefd3.
2022-06-25 11:56:50 -07:00
Kazu Hirata aa8feeefd3 Don't use Optional::hasValue (NFC) 2022-06-25 11:55:57 -07:00
Kazu Hirata ed8fceaa09 Don't use Optional::getValue (NFC) 2022-06-20 23:35:53 -07:00
Walter Erquinigo 1a3f996972 [trace][intelpt] Support system-wide tracing [13] - Add context switch decoding
- Add the logic that parses all cpu context switch traces and produces blocks of continuous executions, which will be later used to assign intel pt subtraces to threads and to identify gaps. This logic can also identify if the context switch trace is malformed.
- The continuous executions blocks are able to indicate when there were some contention issues when producing the context switch trace. See the inline comments for more information.
- Update the 'dump info' command to show information and stats related to the multicore decoding flow, including timing about context switch decoding.
- Add the logic to conver nanoseconds to TSCs.
- Fix a bug when returning the context switches. Now they data returned makes sense and even empty traces can be returned from lldb-server.
- Finish the necessary bits for loading and saving a multi-core trace bundle from disk.
- Change some size_t to uint64_t for compatibility with 32 bit systems.

Tested by saving a trace session of a program that sleeps 100 times, it was able to produce the following 'dump info' text:

```
(lldb) trace load /tmp/trace3/trace.json                                                                   (lldb) thread trace dump info                                                                              Trace technology: intel-pt

thread #1: tid = 4192415
  Total number of instructions: 1

  Memory usage:
    Total approximate memory usage (excluding raw trace): 2.51 KiB
    Average memory usage per instruction (excluding raw trace): 2573.00 bytes

  Timing for this thread:

  Timing for global tasks:
    Context switch trace decoding: 0.00s

  Events:
    Number of instructions with events: 0
    Number of individual events: 0

  Multi-core decoding:
    Total number of continuous executions found: 2499
    Number of continuous executions for this thread: 102

  Errors:
    Number of TSC decoding errors: 0
```

Differential Revision: https://reviews.llvm.org/D126267
2022-06-16 11:23:01 -07:00
Fangrui Song c129220eaa [lldb/gdb-remote] Fix -Wswitch after D116462 2022-04-19 18:01:06 -07:00
Jonas Devlieghere fc54427e76
[lldb] Refactor DataBuffer so we can map files as read-only
Currently, all data buffers are assumed to be writable. This is a
problem on macOS where it's not allowed to load unsigned binaries in
memory as writable. To be more precise, MAP_RESILIENT_CODESIGN and
MAP_RESILIENT_MEDIA need to be set for mapped (unsigned) binaries on our
platform.

Binaries are mapped through FileSystem::CreateDataBuffer which returns a
DataBufferLLVM. The latter is backed by a llvm::WritableMemoryBuffer
because every DataBuffer in LLDB is considered to be writable. In order
to use a read-only llvm::MemoryBuffer I had to split our abstraction
around it.

This patch distinguishes between a DataBuffer (read-only) and
WritableDataBuffer (read-write) and updates LLDB to use the appropriate
one.

rdar://74890607

Differential revision: https://reviews.llvm.org/D122856
2022-04-05 13:46:37 -07:00
Chris Bieneman dfde354958 NFC. Fixing warnings from adding DXContainer
Adds DXContainer to switch statements in Clang and LLDB to silence
warnings.
2022-03-29 14:46:24 -05:00
Jonas Devlieghere 4ef07e5ffe
[lldb] Don't overwrite the host arch with the process arch
Don't overwrite the host architecture (obtained from qHostInfo) with the
process info (obtained from qProcessInfo).

Differential revision: https://reviews.llvm.org/D121442
2022-03-11 09:23:01 -08:00
Pavel Labath c34698a811 [lldb] Rename Logging.h to LLDBLog.h and clean up includes
Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.

After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.
2022-02-03 14:47:01 +01:00
Pavel Labath a007a6d844 [lldb] Convert "LLDB" log channel to the new API 2022-02-02 14:13:08 +01:00
Pavel Labath b1127753b9 [lldb] Convert ProcessGDBRemoteLog to the new API 2022-02-01 14:36:29 +01:00
Michał Górny ac666d1799 [lldb] [gdb-remote] Support getting siginfo via API
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.

Differential Revision: https://reviews.llvm.org/D118055
2022-01-28 17:47:47 +01:00
Michał Górny 59a3f65f5e Revert "[lldb] [gdb-remote] Support getting siginfo via API"
This reverts commit 1a8f60f5f5.
The API requires further work.
2022-01-28 10:15:52 +01:00
Michał Górny 1a8f60f5f5 [lldb] [gdb-remote] Support getting siginfo via API
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.

Differential Revision: https://reviews.llvm.org/D118055
2022-01-27 13:33:47 +01:00
Jason Molenda 8a26ba6a02 Load binary by UUID from qProcessInfo packet fields
Support three new keys in the qProcessInfo response from the remote
gdb stub to handle the case of attaching to a core running some type
of standalone/firmware code and the stub knows the UUID and load
address-or-slide for the binary.  There will be no proper DynamicLoader
plugin in this scenario, but we can try to locate and load the binary
into lldb at the correct offset.

Differential Revision: https://reviews.llvm.org/D116211
rdar://75191077
2021-12-23 15:20:50 -08:00
Pavel Labath a6fedbf20c [lldb/gdb-remote] Remove initial pipe-draining workaround
This code, added in rL197579 (Dec 2013) is supposed to work around what
was presumably a qemu bug, where it would send unsolicited stop-reply
packets after the initial connection.

At present, qemu does not exhibit such behavior. Also, the 10ms delay
introduced by this code is sufficient to mask bugs in other stubs, but
it is not sufficient to *reliably* mask those bugs. This resulted in
flakyness in one of our stubs, which was (incorrectly) sending a +
packet at the start of the connection, resulting in a small-but-annoying
number of dropped connections.

Differential Revision: https://reviews.llvm.org/D114529
2021-11-25 12:33:23 +01:00
Michał Górny 3f1372365a [lldb] Support gdbserver signals
GDB and LLDB use different signal models.  GDB uses a predefined set
of signal codes, and maps platform's signos to them.  On the other hand,
LLDB has historically simply passed native signos.

In order to improve compatibility between LLDB and gdbserver, the GDB
signal model should be used.  However, GDB does not provide a mapping
for all existing signals on Linux and unsupported signals are passed
as 'unknown'.  Limiting LLDB to this behavior could be considered
a regression.

To get the best of both worlds, use the LLDB signal model when talking
to lldb-server, and the GDB signal model otherwise.  For this purpose,
new versions of lldb-server indicate "native-signals+" via qSupported.
At the same time, we also detect older versions of lldb-server
via QThreadSuffixSupported for backwards compatibility.  If neither test
succeeds, we assume gdbserver or another implementation using GDB model.

Differential Revision: https://reviews.llvm.org/D108078
2021-11-10 09:38:55 +01:00
Jonas Devlieghere 6d48e2505c [lldb] Use std::string instead of llvm::Twine in GDBRemoteCommunicationClient
From the documentation:

  A Twine is not intended for use directly and should not be stored, its
  implementation relies on the ability to store pointers to temporary
  stack objects which may be deallocated at the end of a statement.
  Twines should only be used accepted as const references in arguments,
  when an API wishes to accept possibly-concatenated strings.

rdar://84799118

Differential revision: https://reviews.llvm.org/D113314
2021-11-05 13:19:00 -07:00
Pavel Labath f5158ca48c Modernize Platform::GetOSKernelDescription 2021-10-27 10:46:47 +02:00
Pavel Labath 40e4ac3e5b [lldb] Modernize Platform::GetOSBuildString 2021-10-25 15:58:58 +02:00
Kazu Hirata 4ba9d9c84f Use StringRef::contains (NFC) 2021-10-23 20:41:46 -07:00
Michał Górny 66e06cc8cb [llvm] [ADT] Update llvm::Split() per Pavel Labath's suggestions
Optimize the iterator comparison logic to compare Current.data()
pointers.  Use std::tie for assignments from std::pair.  Replace
the custom class with a function returning iterator_range.

Differential Revision: https://reviews.llvm.org/D110535
2021-10-22 12:27:46 +02:00
Pavel Labath f4145c074c [lldb/gdb-remote] Refactor ReadExtFeature
replace stl and lldb apis with standard llvm ones.
2021-10-08 10:43:37 +02:00
Pavel Labath 81a2f39307 [lldb/gdb-remote] Delete SendPacketsAndConcatenateResponses
ReadExtFeature provides equivalent functionality. Also fix a but in
ReadExtFeature, which prevented it from being used for auxv data (it
contains nul characters).
2021-10-07 13:09:27 +02:00
Pavel Labath 156cb4cc64 [lldb] Remove non-stop mode code
We added some support for this mode back in 2015, but the feature was
never productionized. It is completely untested, and there are known
major structural lldb issues that need to be resolved before this
feature can really be supported.

It also complicates making further changes to stop reply packet
handling, which is what I am about to do.

Differential Revision: https://reviews.llvm.org/D110553
2021-09-28 14:13:50 +02:00
Michał Górny f4b71e3479 [llvm] [ADT] Add a range/iterator-based Split()
Add a llvm::Split() implementation that can be used via range-for loop,
e.g.:

    for (StringRef x : llvm::Split("foo,bar,baz", ','))
      ...

The implementation uses an additional SplittingIterator class that
uses StringRef::split() internally.

Differential Revision: https://reviews.llvm.org/D110496
2021-09-27 10:43:09 +02:00
Michał Górny e2f780fba9 [lldb] [gdb-remote] Use llvm::StringRef.split() and llvm::to_integer()
Replace the uses of StringConvert combined with hand-rolled array
splitting with llvm::StringRef.split() and llvm::to_integer().

Differential Revision: https://reviews.llvm.org/D110472
2021-09-26 21:23:26 +02:00
Ted Woodward 953ddded1a [lldb] Handle malformed qfThreadInfo reply
If the remote gdbserver's qfThreadInfo reply has a trailing comma,
GDBRemoteCommunicationClient::GetCurrentProcessAndThreadIDs will return
an empty vector of thread ids. This will cause lldb to recurse through
three functions trying to get the list of threads, until it blows its
stack and crashes.

A trailing comma is a malformed response, but it shouldn't cause lldb to
crash. This patch will return the tids received before the malformed
response.

Reviewed By: clayborg, labath

Differential Revision: https://reviews.llvm.org/D109937
2021-09-23 17:03:47 -05:00
Michał Górny b1099120ff [lldb] [gdb-remote] Always send PID when detaching w/ multiprocess
Always send PID in the detach packet when multiprocess extensions are
enabled.  This is required by qemu's GDB server, as plain 'D' packet
results in an error and the emulated system is not resumed.

Differential Revision: https://reviews.llvm.org/D110033
2021-09-20 13:29:07 +02:00
Michał Górny 3d3017d344 [lldb] [gdb-remote] Use standardized GDB errno values
GDB uses normalized errno values for vFile errors.  Implement
the translation between them and system errno values in the gdb-remote
plugin.

Differential Revision: https://reviews.llvm.org/D108148
2021-09-10 14:08:36 +02:00
Michał Górny 3fade95422 [lldb] [gdb-remote] Support QEnvironment fallback to hex-encoded
Fall back to QEnvironmentHexEncoded if QEnvironment is not supported.
The latter packet is an LLDB extension, while the former is universally
supported.

Add tests for both QEnvironment and QEnvironmentHexEncoded packets,
including both use due to characters that need escaping and fallback
when QEnvironment is not supported.

Differential Revision: https://reviews.llvm.org/D108018
2021-09-10 14:08:36 +02:00
Michał Górny 6ba3f7237d [lldb] [gdb-remote] Implement the vRun packet
Implement the simpler vRun packet and prefer it over the A packet.
Unlike the latter, it tranmits command-line arguments without redundant
indices and lengths.  This also improves GDB compatibility since modern
versions of gdbserver do not implement the A packet at all.

Make qLaunchSuccess not obligatory when using vRun.  It is not
implemented by gdbserver, and since vRun returns the stop reason,
we can assume it to be successful.

Differential Revision: https://reviews.llvm.org/D107931
2021-09-10 14:08:36 +02:00
Michał Górny 501eaf8877 [lldb] [gdb-remote] Add fallbacks for vFile:mode and vFile:exists
Add a GDB-compatible fallback to vFile:fstat for vFile:mode, and to
vFile:open for vFile:exists.  Note that this is only partial fallback,
as it fails if the file cannot be opened.

Differential Revision: https://reviews.llvm.org/D107811
2021-09-10 14:08:36 +02:00
Michał Górny 21e2d7ce43 [lldb] [gdb-remote] Implement fallback to vFile:stat for GetFileSize()
Implement a fallback to getting the file size via vFile:stat packet
when the remote server does not implement vFile:size.  This makes it
possible to query file sizes from remote gdbserver.

Note that unlike vFile:size, the fallback will not work if the server is
unable to open the file.

While at it, add a few tests for the 'platform get-size' command.

Differential Revision: https://reviews.llvm.org/D107780
2021-09-10 11:09:35 +02:00