@samitouri / QOSAMI-WSL-1 / commits / 2c42f23a

diagnostics: collect MSI verbose install logs in diagnostic bundle (#40218)

* diagnostics: collect MSI verbose install log in diagnostic bundle The MSI verbose log (wsl-install-logs.txt) is generated during MSI upgrades via MsiEnableLog but was not collected by the diagnostic script. Additionally, the Store/winget upgrade path (WslInstaller) did not write an MSI log at all when no registry override was set. Changes: - WslInstaller.cpp: default to %TEMP%\wsl-install-logs.txt when UpgradeLogFile registry key is empty, with delete-on-success / preserve-on-failure (same pattern as wsl --update in install.cpp) - collect-wsl-logs.ps1: collect %TEMP%\wsl-install-logs.txt Now all MSI upgrade paths write to the same log location: - wsl --update: already writes here (install.cpp) - Store/winget: now also writes here (WslInstaller.cpp) - Both: delete on success, preserve on failure Tested: installed MSI with file lock contention, collected log contains Warning 1946 detail for diagnosis. Refs: microsoft/WSL#13469, microsoft/WSL#11276, microsoft/WSL#12759 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Address review: handle reboot-required and service temp path - Treat ERROR_SUCCESS_REBOOT_REQUIRED (3010) as success when deciding whether to preserve MSI logs (delete-on-success, keep-on-failure). - Collect logs from both user temp and system temp (WslInstaller service runs as SYSTEM, so its temp_directory_path resolves to %WINDIR%\Temp). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Address review feedback: respect UpgradeLogFile registry, fix collector - Add UpgradeLogInfo struct with fromRegistry flag to skip log deletion when the UpgradeLogFile registry value is explicitly set (per OneBlue) - Remove duplicate system temp copy in collector (per OneBlue) - Fix forward-slash inconsistency in collector (per ptrivedi) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Gordon Lam committed Apr 24, 2026 at 15:31 UTC 2c42f23a759c8ca435546dabcb7da602261dc247

2 files changed +31 -4

diagnostics/collect-wsl-logs.ps1

@@ -177,8 +177,12 @@ if (Test-Path $wslconfig)

177 Copy-Item $wslconfig $folder | Out-Null

178 }

179

180 +# Collect high-level WSL install log (written by WriteInstallLog() in install.cpp)

181 Copy-Item "C:\Windows\temp\wsl-install-log.txt" $folder -ErrorAction ignore

182

183 +# Collect MSI verbose install log (preserved on failure by wsl --update or WslInstaller service).

184 +Copy-Item "$env:TEMP\wsl-install-logs.txt" $folder -ErrorAction ignore

185 +

186 get-appxpackage MicrosoftCorporationII.WindowsSubsystemforLinux -ErrorAction Ignore > $folder/appxpackage.txt

187 get-acl "C:\ProgramData\Microsoft\Windows\WindowsApps" -ErrorAction Ignore | Format-List > $folder/acl.txt

188 Get-WindowsOptionalFeature -Online > $folder/optional-components.txt

src/windows/wslinstaller/exe/WslInstaller.cpp

+27 -4

@@ -31,18 +31,26 @@ std::wstring GetMsiPackagePath()

31 return (wsl::windows::common::wslutil::GetBasePath() / L"wsl.msi").wstring();

32 }

34 -std::optional<std::wstring> GetUpgradeLogFileLocation()

34 +struct UpgradeLogInfo

35 +{

36 + std::wstring path;

37 + bool fromRegistry; // true when the path was explicitly configured via UpgradeLogFile registry value

38 +};

39 +

40 +std::optional<UpgradeLogInfo> GetUpgradeLogFileLocation()

41 try

42 {

43 const auto key = wsl::windows::common::registry::OpenLxssMachineKey();

44 const auto path = wsl::windows::common::registry::ReadString(key.get(), L"MSI", L"UpgradeLogFile", L"");

45 if (path.empty())

46 {

41 - return {};

47 + // Default to the same path used by wsl --update so all MSI logs

48 + // are collected from one location by the diagnostic script.

49 + return UpgradeLogInfo{(std::filesystem::temp_directory_path() / L"wsl-install-logs.txt").wstring(), false};

50 }

52 // A canonical path is required because msiexec doesn't like symlinks.

45 - return std::filesystem::weakly_canonical(path);

53 + return UpgradeLogInfo{std::filesystem::weakly_canonical(path), true};

54 }

55 catch (...)

56 {

@@ -54,6 +62,16 @@ std::pair<UINT, std::wstring> InstallMsipackageImpl()

62 {

63 const auto logFile = GetUpgradeLogFileLocation();

65 + // Delete MSI log on success, preserve on failure for diagnostics (same as wsl --update).

66 + // When the UpgradeLogFile registry value is set, always keep the log — the registry key

67 + // is explicitly designed to retain MSI logs across installs.

68 + auto clearLogs = wil::scope_exit_log(WI_DIAGNOSTICS_INFO, [&logFile]() {

69 + if (logFile.has_value() && !logFile->fromRegistry)

70 + {

71 + LOG_IF_WIN32_BOOL_FALSE(DeleteFile(logFile->path.c_str()));

72 + }

73 + });

74 +

75 std::wstring errors;

76 auto messageCallback = [&errors](INSTALLMESSAGE type, LPCWSTR message) {

77 switch (type)

@@ -77,7 +95,7 @@ std::pair<UINT, std::wstring> InstallMsipackageImpl()

95 };

97 auto result = wsl::windows::common::install::UpgradeViaMsi(

80 - GetMsiPackagePath().c_str(), L"SKIPMSIX=1", logFile.has_value() ? logFile->c_str() : nullptr, messageCallback);

98 + GetMsiPackagePath().c_str(), L"SKIPMSIX=1", logFile.has_value() ? logFile->path.c_str() : nullptr, messageCallback);

100 // ERROR_SUCCESS_REBOOT_REQUIRED (3010) means the install succeeded but some files

101 // will be replaced on the next reboot. Treat as success since the service runs

@@ -94,6 +112,11 @@ std::pair<UINT, std::wstring> InstallMsipackageImpl()

112 TraceLoggingValue(rebootRequired, "rebootRequired"),

113 TraceLoggingValue(errors.c_str(), "errorMessage"));

114

115 + if (result != ERROR_SUCCESS && result != ERROR_SUCCESS_REBOOT_REQUIRED)

116 + {

117 + clearLogs.release();

118 + }

119 +

120 return {result, errors};

121 }

122