validation: fix deadlock in XrDestroyInstance #23
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
GenValidUsageNextXrDestroyInstance locks the non-recursive g_instance_dispatch_mutex and then calls GenValidUsageCleanUpMaps under the lock, which calls EraseAllInstanceTableMapElements, which tries to lock g_instance_dispatch_mutex again, causing a deadlock. Since EraseAllInstanceTableMapElements is only called from GenValidUsageNextXrDestroyInstance, g_instance_dispatch_mutex is always guaranteed to be locked, so drop the local std::unique_lock.
|
oh jeepers, I totally didn't see this or your other one before submitting #24 , you must not have been in one of the channels where I warned "hey I'm changing a zillion validation things". I'll see if I can port this across. The code is simpler post-refactoring, but still may share the underlying issue of "it's already locked", haven't dug into too far. (I did manage to shrink lock periods substantially in some cases, so there's a chance it's fixed, but not 100% sure esp. since I'm getting #25 )
|
rpavlik
approved these changes
Apr 2, 2019
|
Merging since validation is broken without this. |
rpavlik
added a commit
that referenced
this pull request
May 9, 2019
No API changes, and only minimal consistency changes to the spec/registry. Mostly an update for tooling, layers, loader, and sample code. Header version has been bumped to 43, but no symbols that should have actually been in use have changed. ### GitHub Pull Requests These had been integrated into the public repo incrementally. - General, Build, Other - #8, #11, #12 - Improve BUILDING and README - #9 - Make Vulkan SDK dependency optional - #17 - Add install target to CMake files - #17 - API dump layer, build: timespec extension fixes - #19 - build: fix CMAKE_PRESENTATION_BACKEND default on linux - #34 - list: Fix list test output - validation layer - #18, #22, #23 - Fix build and execution - #24 - Fix crash and refactor - hello_xr - #13 - Do not query GL context API version before creating context - #26 - Fix a warning - Loader - #3 - Don't cross 32/64 registry silos - #14 - Initialize XrExtensionProperties array parameter for rt_xrEnumerateInstanceExtensionProperties - #20 - Fix Linux manifest file search - #30 - Add default implementations of API functions to dispatch chains - #32 - Avoid crash when evaluating layer disable environment vars - #35 - Add 'unknown' strings to loader's *ToString fallback functions - #36 - Allow null instance in xrGetInstanceProcAddr() for certain entry points - #39 - Default to static loader only on Windows ### Internal Issues - General, Build, Other - Unify (for the most part) the OpenXR and Vulkan generator scripts. (internal MR 1166) - List instance extensions in the "list" test. (internal MR 1169) - Avoid dllexport for all apps compiled with `openxr_platform_defines.h` (internal MR 1187) - Don't offer `BUILD_SPECIFICATION` unless the spec makefile is there. (internal MR 1179) - Add simple input example to hello_xr. (internal MR 1178) - Add a clang-format script for ease of development. - API Registry and Headers - Remove impossible and undocumented error codes. (internal MR 1185 and 1189) - Mark layers in `XrFrameEndInfo` as optional. (internal MR 1151, internal issue 899) - Remove unused windows types from `openxr_platform.h` (internal MR 1197) - Make `openxr_platform.h` include `openxr.h` on which it depends. (internal MR 1140, internal issue 918) - Remove unused, undocumented defines. (internal MR 1238, internal issue 1012) - Loader - Fix loader regkey search logic so 64bit application loads 64bit regkey value. (internal MR 1180) - Modify loader to be friendly to UWP (Universal Windows Platform) build target. (internal MR 1198)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
GenValidUsageNextXrDestroyInstancelocks the non-recursiveg_instance_dispatch_mutexand then callsGenValidUsageCleanUpMapsunder the lock, which callsEraseAllInstanceTableMapElements, which tries to lockg_instance_dispatch_mutexagain, causing a deadlock.Since
EraseAllInstanceTableMapElementsis only called fromGenValidUsageNextXrDestroyInstance,g_instance_dispatch_mutexis always guaranteed to be locked, so drop the localstd::unique_lock.