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Changeset 259673 in webkit


Ignore:
Timestamp:
Apr 7, 2020, 3:07:54 PM (6 years ago)
Author:
commit-queue@webkit.org
Message:

Simplify and fortify network getNetworkProcessConnection and getGPUProcessConnection
​https://bugs.webkit.org/show_bug.cgi?id=210142
<rdar://problem/59488963>

Patch by Alex Christensen <​achristensen@webkit.org> on 2020-04-07
Reviewed by Youenn Fablet.

We have reports of hangs inside WebKit::getNetworkProcessConnection that seem to last forever.
Some of the reports indicate the network process is being suspended while a connection is being established with it.

To fix this issue we do three things:

  1. We take a foregroundActivity when sending an async message to establish a connection.
  2. We use sendWithAsyncReply which already has logic to handle the case where we are currently launching the process. Instead of the complicated retry logic, we add a retry attempt in WebProcessPool if the connection identifier is invalid.
  3. Add some release logging so we can better diagnose problems with this flow in the future.

The functional change is adding the foreground activity, which should prevent some hangs.
The rest is just to make this code more sane to understand and debug.
I do the same changes to NetworkProcess and GPUProcess because they are intended to be the same. The latter is based on the former.

The API test WebKit.NetworkProcessCrashWithPendingConnection covers what happens when the network process crashes during connection establishment.
It fails if we don't retry somewhere, which I did in WebProcessPool. We also need to try again in getNetworkProcessConnection and getGPUProcessConnection.
If it fails twice, there's nothing we can do, and we crash the web process to avoid a crash loop.

  • UIProcess/GPU/GPUProcessProxy.cpp:

(WebKit::GPUProcessProxy::getGPUProcessConnection):
(WebKit::GPUProcessProxy::didFinishLaunching):
(WebKit::GPUProcessProxy::~GPUProcessProxy): Deleted.
(WebKit::GPUProcessProxy::openGPUProcessConnection): Deleted.

  • UIProcess/GPU/GPUProcessProxy.h:
  • UIProcess/Network/NetworkProcessProxy.cpp:

(WebKit::NetworkProcessProxy::~NetworkProcessProxy):
(WebKit::NetworkProcessProxy::getNetworkProcessConnection):
(WebKit::NetworkProcessProxy::networkProcessCrashed):
(WebKit::NetworkProcessProxy::didFinishLaunching):
(WebKit::NetworkProcessProxy::openNetworkProcessConnection): Deleted.

  • UIProcess/Network/NetworkProcessProxy.h:
  • UIProcess/WebProcessPool.cpp:

(WebKit::WebProcessPool::networkProcessCrashed):
(WebKit::WebProcessPool::getNetworkProcessConnection):
(WebKit::WebProcessPool::getGPUProcessConnection):

  • UIProcess/WebProcessPool.h:
  • WebProcess/GPU/GPUProcessConnectionInfo.h:

(WebKit::GPUProcessConnectionInfo::identifier const):
(WebKit::GPUProcessConnectionInfo::identifier): Deleted.

  • WebProcess/Network/NetworkProcessConnectionInfo.h:

(WebKit::NetworkProcessConnectionInfo::identifier const):
(WebKit::NetworkProcessConnectionInfo::identifier): Deleted.

Location:
trunk/Source/WebKit
Files:
10 edited

Legend:

Unmodified
Added
Removed

  • trunk/Source/WebKit/ChangeLog

    r259672 r259673  
     12020-04-07  Alex Christensen  <achristensen@webkit.org>
     2
     3        Simplify and fortify network getNetworkProcessConnection and getGPUProcessConnection
     4        https://bugs.webkit.org/show_bug.cgi?id=210142
     5        <rdar://problem/59488963>
     6
     7        Reviewed by Youenn Fablet.
     8
     9        We have reports of hangs inside WebKit::getNetworkProcessConnection that seem to last forever.
     10        Some of the reports indicate the network process is being suspended while a connection is being established with it.
     11
     12        To fix this issue we do three things:
     13        1. We take a foregroundActivity when sending an async message to establish a connection.
     14        2. We use sendWithAsyncReply which already has logic to handle the case where we are currently launching the process.
     15           Instead of the complicated retry logic, we add a retry attempt in WebProcessPool if the connection identifier is invalid.
     16        3. Add some release logging so we can better diagnose problems with this flow in the future.
     17
     18        The functional change is adding the foreground activity, which should prevent some hangs.
     19        The rest is just to make this code more sane to understand and debug.
     20        I do the same changes to NetworkProcess and GPUProcess because they are intended to be the same.  The latter is based on the former.
     21
     22        The API test WebKit.NetworkProcessCrashWithPendingConnection covers what happens when the network process crashes during connection establishment.
     23        It fails if we don't retry somewhere, which I did in WebProcessPool.  We also need to try again in getNetworkProcessConnection and getGPUProcessConnection.
     24        If it fails twice, there's nothing we can do, and we crash the web process to avoid a crash loop.
     25
     26        * UIProcess/GPU/GPUProcessProxy.cpp:
     27        (WebKit::GPUProcessProxy::getGPUProcessConnection):
     28        (WebKit::GPUProcessProxy::didFinishLaunching):
     29        (WebKit::GPUProcessProxy::~GPUProcessProxy): Deleted.
     30        (WebKit::GPUProcessProxy::openGPUProcessConnection): Deleted.
     31        * UIProcess/GPU/GPUProcessProxy.h:
     32        * UIProcess/Network/NetworkProcessProxy.cpp:
     33        (WebKit::NetworkProcessProxy::~NetworkProcessProxy):
     34        (WebKit::NetworkProcessProxy::getNetworkProcessConnection):
     35        (WebKit::NetworkProcessProxy::networkProcessCrashed):
     36        (WebKit::NetworkProcessProxy::didFinishLaunching):
     37        (WebKit::NetworkProcessProxy::openNetworkProcessConnection): Deleted.
     38        * UIProcess/Network/NetworkProcessProxy.h:
     39        * UIProcess/WebProcessPool.cpp:
     40        (WebKit::WebProcessPool::networkProcessCrashed):
     41        (WebKit::WebProcessPool::getNetworkProcessConnection):
     42        (WebKit::WebProcessPool::getGPUProcessConnection):
     43        * UIProcess/WebProcessPool.h:
     44        * WebProcess/GPU/GPUProcessConnectionInfo.h:
     45        (WebKit::GPUProcessConnectionInfo::identifier const):
     46        (WebKit::GPUProcessConnectionInfo::identifier): Deleted.
     47        * WebProcess/Network/NetworkProcessConnectionInfo.h:
     48        (WebKit::NetworkProcessConnectionInfo::identifier const):
     49        (WebKit::NetworkProcessConnectionInfo::identifier): Deleted.
     50
    1512020-04-07  Simon Fraser  <simon.fraser@apple.com>
    252

  • trunk/Source/WebKit/UIProcess/GPU/GPUProcessProxy.cpp

    r258322 r259673  
    133133}
    134134
    135 GPUProcessProxy::~GPUProcessProxy()
    136 {
    137     for (auto& request : m_connectionRequests.values())
    138         request.reply({ });
    139 }
     135GPUProcessProxy::~GPUProcessProxy() = default;
    140136
    141137#if ENABLE(MEDIA_STREAM)
    … …  
    179175void GPUProcessProxy::getGPUProcessConnection(WebProcessProxy& webProcessProxy, Messages::WebProcessProxy::GetGPUProcessConnection::DelayedReply&& reply)
    180176{
    181     m_connectionRequests.add(++m_connectionRequestIdentifier, ConnectionRequest { makeWeakPtr(webProcessProxy), WTFMove(reply) });
    182     if (state() == State::Launching)
    183         return;
    184     openGPUProcessConnection(m_connectionRequestIdentifier, webProcessProxy);
    185 }
    186 
    187 void GPUProcessProxy::openGPUProcessConnection(ConnectionRequestIdentifier connectionRequestIdentifier, WebProcessProxy& webProcessProxy)
    188 {
    189177    addSession(webProcessProxy.websiteDataStore());
    190    
    191178#if HAVE(VISIBILITY_PROPAGATION_VIEW)
    192179    if (m_contextIDForVisibilityPropagation)
    … …  
    196183#endif
    197184
    198     sendWithAsyncReply(Messages::GPUProcess::CreateGPUConnectionToWebProcess { webProcessProxy.coreProcessIdentifier(), webProcessProxy.sessionID() }, [this, weakThis = makeWeakPtr(this), webProcessProxy = makeWeakPtr(webProcessProxy), connectionRequestIdentifier](auto&& connectionIdentifier) mutable {
    199         if (!weakThis)
    200             return;
    201 
    202         if (!connectionIdentifier) {
    203             // GPU process probably crashed, the connection request should have been moved.
    204             ASSERT(m_connectionRequests.isEmpty());
    205             return;
     185    RELEASE_LOG(ProcessSuspension, "%p - GPUProcessProxy is taking a background assertion because a web process is requesting a connection", this);
     186    sendWithAsyncReply(Messages::GPUProcess::CreateGPUConnectionToWebProcess { webProcessProxy.coreProcessIdentifier(), webProcessProxy.sessionID() }, [this, weakThis = makeWeakPtr(*this), reply = WTFMove(reply), activity = throttler().backgroundActivity("GPUProcessProxy::getGPUProcessConnection"_s)](auto&& connectionIdentifier) mutable {
     187        if (!weakThis) {
     188            RELEASE_LOG_ERROR(Process, "GPUProcessProxy::getGPUProcessConnection: GPUProcessProxy deallocated during connection establishment");
     189            return reply({ });
    206190        }
    207 
    208         ASSERT(m_connectionRequests.contains(connectionRequestIdentifier));
    209         auto request = m_connectionRequests.take(connectionRequestIdentifier);
    210 
    211191#if USE(UNIX_DOMAIN_SOCKETS) || OS(WINDOWS)
    212         request.reply(GPUProcessConnectionInfo { WTFMove(*connectionIdentifier) });
     192        reply(GPUProcessConnectionInfo { WTFMove(*connectionIdentifier) });
    213193#elif OS(DARWIN)
    214194        MESSAGE_CHECK(MACH_PORT_VALID(connectionIdentifier->port()));
    215         request.reply(GPUProcessConnectionInfo { IPC::Attachment { connectionIdentifier->port(), MACH_MSG_TYPE_MOVE_SEND }, this->connection()->getAuditToken() });
     195        reply(GPUProcessConnectionInfo { IPC::Attachment { connectionIdentifier->port(), MACH_MSG_TYPE_MOVE_SEND }, this->connection()->getAuditToken() });
    216196#else
    217197        notImplemented();
    … …  
    253233        gpuProcessCrashed();
    254234        return;
    255     }
    256 
    257     auto connectionRequests = WTFMove(m_connectionRequests);
    258     for (auto& connectionRequest : connectionRequests.values()) {
    259         if (connectionRequest.webProcess)
    260             getGPUProcessConnection(*connectionRequest.webProcess, WTFMove(connectionRequest.reply));
    261         else
    262             connectionRequest.reply({ });
    263235    }
    264236   

  • trunk/Source/WebKit/UIProcess/GPU/GPUProcessProxy.h

    r259540 r259673  
    9797    void didFinishLaunching(ProcessLauncher*, IPC::Connection::Identifier) override;
    9898
    99     typedef uint64_t ConnectionRequestIdentifier;
    100     void openGPUProcessConnection(ConnectionRequestIdentifier, WebProcessProxy&);
    101 
    10299    // IPC::Connection::Client
    103100    void didReceiveMessage(IPC::Connection&, IPC::Decoder&) override;
    … …  
    110107
    111108    static GPUProcessProxy* m_singleton;
    112 
    113     struct ConnectionRequest {
    114         WeakPtr<WebProcessProxy> webProcess;
    115         Messages::WebProcessProxy::GetGPUProcessConnectionDelayedReply reply;
    116     };
    117     ConnectionRequestIdentifier m_connectionRequestIdentifier { 0 };
    118     HashMap<ConnectionRequestIdentifier, ConnectionRequest> m_connectionRequests;
    119109
    120110    ProcessThrottler m_throttler;

  • trunk/Source/WebKit/UIProcess/Network/NetworkProcessProxy.cpp

    r259540 r259673  
    109109    if (m_downloadProxyMap)
    110110        m_downloadProxyMap->invalidate();
    111 
    112     for (auto& request : m_connectionRequests.values())
    113         request.reply({ });
    114111}
    115112
    … …  
    141138void NetworkProcessProxy::getNetworkProcessConnection(WebProcessProxy& webProcessProxy, Messages::WebProcessProxy::GetNetworkProcessConnection::DelayedReply&& reply)
    142139{
    143     m_connectionRequests.add(++m_connectionRequestIdentifier, ConnectionRequest { makeWeakPtr(webProcessProxy), WTFMove(reply) });
    144     if (state() == State::Launching)
    145         return;
    146     openNetworkProcessConnection(m_connectionRequestIdentifier, webProcessProxy);
    147 }
    148 
    149 void NetworkProcessProxy::openNetworkProcessConnection(uint64_t connectionRequestIdentifier, WebProcessProxy& webProcessProxy)
    150 {
    151     connection()->sendWithAsyncReply(Messages::NetworkProcess::CreateNetworkConnectionToWebProcess { webProcessProxy.coreProcessIdentifier(), webProcessProxy.sessionID() }, [this, weakThis = makeWeakPtr(this), webProcessProxy = makeWeakPtr(webProcessProxy), connectionRequestIdentifier](auto&& connectionIdentifier, HTTPCookieAcceptPolicy cookieAcceptPolicy) mutable {
    152         if (!weakThis)
    153             return;
    154 
    155         if (!connectionIdentifier) {
    156             // Network process probably crashed, the connection request should have been moved.
    157             ASSERT(m_connectionRequests.isEmpty());
    158             return;
     140    RELEASE_LOG(ProcessSuspension, "%p - NetworkProcessProxy is taking a background assertion because a web process is requesting a connection", this);
     141    sendWithAsyncReply(Messages::NetworkProcess::CreateNetworkConnectionToWebProcess { webProcessProxy.coreProcessIdentifier(), webProcessProxy.sessionID() }, [this, weakThis = makeWeakPtr(*this), reply = WTFMove(reply), activity = throttler().backgroundActivity("NetworkProcessProxy::getNetworkProcessConnection"_s)](auto&& connectionIdentifier, auto cookieAcceptPolicy) mutable {
     142        if (!weakThis) {
     143            RELEASE_LOG_ERROR(Process, "NetworkProcessProxy::getNetworkProcessConnection: NetworkProcessProxy deallocated during connection establishment");
     144            return reply({ });
    159145        }
    160146
    161         ASSERT(m_connectionRequests.contains(connectionRequestIdentifier));
    162         auto request = m_connectionRequests.take(connectionRequestIdentifier);
    163 
    164147#if USE(UNIX_DOMAIN_SOCKETS) || OS(WINDOWS)
    165         request.reply(NetworkProcessConnectionInfo { WTFMove(*connectionIdentifier), cookieAcceptPolicy });
     148        reply(NetworkProcessConnectionInfo { WTFMove(*connectionIdentifier), cookieAcceptPolicy });
    166149#elif OS(DARWIN)
    167150        MESSAGE_CHECK(MACH_PORT_VALID(connectionIdentifier->port()));
    168         request.reply(NetworkProcessConnectionInfo { IPC::Attachment { connectionIdentifier->port(), MACH_MSG_TYPE_MOVE_SEND }, cookieAcceptPolicy, connection()->getAuditToken() });
     151        reply(NetworkProcessConnectionInfo { IPC::Attachment { connectionIdentifier->port(), MACH_MSG_TYPE_MOVE_SEND }, cookieAcceptPolicy, connection()->getAuditToken() });
    169152#else
    170153        notImplemented();
    … …  
    249232    clearCallbackStates();
    250233
    251     Vector<std::pair<RefPtr<WebProcessProxy>, Messages::WebProcessProxy::GetNetworkProcessConnection::DelayedReply>> pendingRequests;
    252     pendingRequests.reserveInitialCapacity(m_connectionRequests.size());
    253     for (auto& request : m_connectionRequests.values()) {
    254         if (request.webProcess)
    255             pendingRequests.uncheckedAppend(std::make_pair(makeRefPtr(request.webProcess.get()), WTFMove(request.reply)));
    256         else
    257             request.reply({ });
    258     }
    259     m_connectionRequests.clear();
    260 
    261234    // Tell the network process manager to forget about this network process proxy. This will cause us to be deleted.
    262     m_processPool.networkProcessCrashed(*this, WTFMove(pendingRequests));
     235    m_processPool.networkProcessCrashed(*this);
    263236}
    264237
    … …  
    408381        networkProcessCrashed();
    409382        return;
    410     }
    411 
    412     auto connectionRequests = WTFMove(m_connectionRequests);
    413     for (auto& connectionRequest : connectionRequests.values()) {
    414         if (connectionRequest.webProcess)
    415             getNetworkProcessConnection(*connectionRequest.webProcess, WTFMove(connectionRequest.reply));
    416         else
    417             connectionRequest.reply({ });
    418383    }
    419384

  • trunk/Source/WebKit/UIProcess/Network/NetworkProcessProxy.h

    r259540 r259673  
    287287    void didFinishLaunching(ProcessLauncher*, IPC::Connection::Identifier) override;
    288288
    289     void openNetworkProcessConnection(uint64_t connectionRequestIdentifier, WebProcessProxy&);
    290 
    291289    void processAuthenticationChallenge(PAL::SessionID, Ref<AuthenticationChallengeProxy>&&);
    292290
    293291    WebProcessPool& m_processPool;
    294 
    295     struct ConnectionRequest {
    296         WeakPtr<WebProcessProxy> webProcess;
    297         Messages::WebProcessProxy::GetNetworkProcessConnectionDelayedReply reply;
    298     };
    299     uint64_t m_connectionRequestIdentifier { 0 };
    300     HashMap<uint64_t, ConnectionRequest> m_connectionRequests;
    301292
    302293    HashMap<uint64_t, CompletionHandler<void(WebsiteData)>> m_pendingFetchWebsiteDataCallbacks;

  • trunk/Source/WebKit/UIProcess/WebProcessPool.cpp

    r259540 r259673  
    4040#include "DownloadProxy.h"
    4141#include "DownloadProxyMessages.h"
     42#include "GPUProcessConnectionInfo.h"
    4243#include "GamepadData.h"
    4344#include "HighPerformanceGraphicsUsageSampler.h"
    … …  
    4546#include "LogInitialization.h"
    4647#include "Logging.h"
     48#include "NetworkProcessConnectionInfo.h"
    4749#include "NetworkProcessCreationParameters.h"
    4850#include "NetworkProcessMessages.h"
    … …  
    712714}
    713715
    714 void WebProcessPool::networkProcessCrashed(NetworkProcessProxy& networkProcessProxy, Vector<std::pair<RefPtr<WebProcessProxy>, Messages::WebProcessProxy::GetNetworkProcessConnection::DelayedReply>>&& pendingReplies)
     716void WebProcessPool::networkProcessCrashed(NetworkProcessProxy& networkProcessProxy)
    715717{
    716718    ASSERT(m_networkProcess);
    … …  
    728730    m_networkProcess = nullptr;
    729731
    730     // Attempt to re-launch.
    731     if (pendingReplies.isEmpty())
    732         return;
    733     auto& newNetworkProcess = ensureNetworkProcess();
    734     for (auto& reply : pendingReplies)
    735         newNetworkProcess.getNetworkProcessConnection(*reply.first, WTFMove(reply.second));
    736 
    737732    terminateServiceWorkers();
    738733}
    … …  
    748743{
    749744    ensureNetworkProcess();
    750     ASSERT(m_networkProcess);
    751 
    752     m_networkProcess->getNetworkProcessConnection(webProcessProxy, WTFMove(reply));
     745    m_networkProcess->getNetworkProcessConnection(webProcessProxy, [this, weakThis = makeWeakPtr(*this), webProcessProxy = makeWeakPtr(webProcessProxy), reply = WTFMove(reply)] (auto& connectionInfo) mutable {
     746        if (UNLIKELY(!IPC::Connection::identifierIsValid(connectionInfo.identifier()) && webProcessProxy && weakThis)) {
     747            WEBPROCESSPOOL_RELEASE_LOG_ERROR(Process, "getNetworkProcessConnection: Failed first attempt, retrying");
     748            ensureNetworkProcess();
     749            m_networkProcess->getNetworkProcessConnection(*webProcessProxy, WTFMove(reply));
     750            return;
     751        }
     752        reply(connectionInfo);
     753    });
    753754}
    754755
    … …  
    765766void WebProcessPool::getGPUProcessConnection(WebProcessProxy& webProcessProxy, Messages::WebProcessProxy::GetGPUProcessConnection::DelayedReply&& reply)
    766767{
    767     GPUProcessProxy::singleton().getGPUProcessConnection(webProcessProxy, WTFMove(reply));
     768    GPUProcessProxy::singleton().getGPUProcessConnection(webProcessProxy, [this, weakThis = makeWeakPtr(*this), webProcessProxy = makeWeakPtr(webProcessProxy), reply = WTFMove(reply)] (auto& connectionInfo) mutable {
     769        if (UNLIKELY(!IPC::Connection::identifierIsValid(connectionInfo.identifier()) && webProcessProxy && weakThis)) {
     770            WEBPROCESSPOOL_RELEASE_LOG_ERROR(Process, "getGPUProcessConnection: Failed first attempt, retrying");
     771            GPUProcessProxy::singleton().getGPUProcessConnection(*webProcessProxy, WTFMove(reply));
     772            return;
     773        }
     774        reply(connectionInfo);
     775    });
    768776}
    769777#endif

  • trunk/Source/WebKit/UIProcess/WebProcessPool.h

    r258949 r259673  
    390390    NetworkProcessProxy& ensureNetworkProcess(WebsiteDataStore* withWebsiteDataStore = nullptr);
    391391    NetworkProcessProxy* networkProcess() { return m_networkProcess.get(); }
    392     void networkProcessCrashed(NetworkProcessProxy&, Vector<std::pair<RefPtr<WebProcessProxy>, Messages::WebProcessProxy::GetNetworkProcessConnectionDelayedReply>>&&);
     392    void networkProcessCrashed(NetworkProcessProxy&);
    393393
    394394    void getNetworkProcessConnection(WebProcessProxy&, Messages::WebProcessProxy::GetNetworkProcessConnectionDelayedReply&&);

  • trunk/Source/WebKit/WebProcess/GPU/GPUProcessConnectionInfo.h

    r254392 r259673  
    3636#endif
    3737
    38     IPC::Connection::Identifier identifier()
     38    IPC::Connection::Identifier identifier() const
    3939    {
    4040#if USE(UNIX_DOMAIN_SOCKETS)

  • trunk/Source/WebKit/WebProcess/Network/NetworkProcessConnectionInfo.h

    r254931 r259673  
    3737#endif
    3838
    39     IPC::Connection::Identifier identifier()
     39    IPC::Connection::Identifier identifier() const
    4040    {
    4141#if USE(UNIX_DOMAIN_SOCKETS)

  • trunk/Source/WebKit/WebProcess/WebProcess.cpp

    r259307 r259673  
    10951095    NetworkProcessConnectionInfo connectionInfo;
    10961096    if (!connection.sendSync(Messages::WebProcessProxy::GetNetworkProcessConnection(), Messages::WebProcessProxy::GetNetworkProcessConnection::Reply(connectionInfo), 0)) {
     1097        // If we failed the first time, retry once. The attachment may have become invalid
     1098        // before it was received by the web process if the network process crashed.
     1099        if (!connection.sendSync(Messages::WebProcessProxy::GetNetworkProcessConnection(), Messages::WebProcessProxy::GetNetworkProcessConnection::Reply(connectionInfo), 0)) {
    10971100#if PLATFORM(GTK) || PLATFORM(WPE)
    1098         // GTK+ and WPE ports don't exit on send sync message failure.
    1099         // In this particular case, the network process can be terminated by the UI process while the
    1100         // Web process is still initializing, so we always want to exit instead of crashing. This can
    1101         // happen when the WebView is created and then destroyed quickly.
    1102         // See https://bugs.webkit.org/show_bug.cgi?id=183348.
    1103         exit(0);
     1101            // GTK+ and WPE ports don't exit on send sync message failure.
     1102            // In this particular case, the network process can be terminated by the UI process while the
     1103            // Web process is still initializing, so we always want to exit instead of crashing. This can
     1104            // happen when the WebView is created and then destroyed quickly.
     1105            // See https://bugs.webkit.org/show_bug.cgi?id=183348.
     1106            exit(0);
    11041107#else
    1105         CRASH();
    1106 #endif
     1108            CRASH();
     1109#endif
     1110        }
    11071111    }
    11081112
    … …  
    12181222{
    12191223    GPUProcessConnectionInfo connectionInfo;
    1220     if (!connection.sendSync(Messages::WebProcessProxy::GetGPUProcessConnection(), Messages::WebProcessProxy::GetGPUProcessConnection::Reply(connectionInfo), 0))
    1221         CRASH();
     1224    if (!connection.sendSync(Messages::WebProcessProxy::GetGPUProcessConnection(), Messages::WebProcessProxy::GetGPUProcessConnection::Reply(connectionInfo), 0)) {
     1225        // If we failed the first time, retry once. The attachment may have become invalid
     1226        // before it was received by the web process if the network process crashed.
     1227        if (!connection.sendSync(Messages::WebProcessProxy::GetGPUProcessConnection(), Messages::WebProcessProxy::GetGPUProcessConnection::Reply(connectionInfo), 0))
     1228            CRASH();
     1229    }
    12221230
    12231231    return connectionInfo;
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