[webkit-dev] Gdklauncher Craches

Thu Feb 22 20:25:03 PST 2007

On 2/22/07, Krzysztof Kowalczyk <kkowalczyk at gmail.com> wrote:
> Looking more closely at both callstacks, there is a re-entrance in
> curl i.e. a data callback is called from within curl_multi_perform, it
> triggers html processing which triggers a download of another resource
> which enters curl again. Maybe the problem is that curl version on
> Ubuntu 6.10 is not re-entrant (or maybe it's not re-entrant at all and
> I'm just lucky to not see it so often using custom debug build of
> latest curl code).
>

This should work.  Did you get my latest changes in ?
I fixed a few bugs some stuff with malloc's etc that was causing
crashes like what your seeing
when a second resource was loaded. So their were bugs in the code that
caused crashes on the second load that where fixed.

> Either way, my final plan is to move curl networking to a separate
> thread, the way qt and windows do, so that the app can be more
> responsive (currently I see cases where blocking network calls,
> especially DNS resolution, stalls gdklauncher for a long time). That
> might help with this problem since in that model the curl data
> callback would just post received data for processing to the main
> thread, removing the curl re-entrancy. But don't hold your breath -
> for now I would recommend building your own curl library.
>
> -- kjk
>
> On 2/22/07, Robin Dunn <robin at alldunn.com> wrote:
> > Krzysztof Kowalczyk wrote:
> > > On my Ubuntu 6.10 with the default curl libraries (7.15.4, I believe),
> > > I've been seeing often crashes in curl. They all pretty much went away
> > > when I uninstalled curl and build my own debug version from latest
> > > curl sources (http://curl.haxx.se/download/curl-7.16.1.tar.gz) and
> > > made gdklauncher use that.
> > >
> > > While it's hard for me to believe that such a widely used library like
> > > curl could be broken on one of the most popular distros, the evidence
> > > is in favor of that conclusion.
> > >
> > > Another possibility is that we're not using curl code correctly in gdk
> > > port and newer version (or debug build) is more resilient to that
> > > incorrect usage, but I spent some time studying the code and nothing
> > > jumps out as wrong.
> >
> >
> > I can confirm this problem when using the wxWidgets build on Linux (also
> > Ubuntu 6.10 here.)  I've pasted a gdb backtrace below since mine is a
> > little different than the one posted already.  Maybe that will give some
> > additional hints for fixing this.
> >
> > Also, on Windows when using libcurl for the network layer it's possible
> > that the first time that downloadTimerCallback is called for each job
> > that curl_multi_fdset will not load any handles into the fd_sets, so the
> > call to select will fail, returning -1.  However this seems to be a
> > valid state so downloadTimerCallback should not be bailing out as it
> > currently does right after the select() call.  Commenting out that if
> > statement allows it to work properly and be able to do the downloading
> > on subsequent timer callbacks.
> >
> >
> > Here's the backtrace on Ubuntu:
> >
> > Program received signal SIGSEGV, Segmentation fault.
> > 0xb7358f52 in curl_memdebug () from /usr/lib/libcurl.so.3
> > (gdb) bt
> > #0  0xb7358f52 in curl_memdebug () from /usr/lib/libcurl.so.3
> > #1  0xb7358fa5 in curl_memdebug () from /usr/lib/libcurl.so.3
> > #2  0xb735a5de in curl_multi_add_handle () from /usr/lib/libcurl.so.3
> > #3  0xb6ea218a in WebCore::ResourceHandleManager::add (this=0x825c5a8,
> > job=0x845b450) at ../../platform/network/gdk/ResourceHandleManager.cpp:239
> > #4  0xb6e9ff1f in WebCore::ResourceHandle::start (this=0x845b450,
> > frame=0x822b630) at ../../platform/network/gdk/ResourceHandleCurl.cpp:56
> > #5  0xb6e6bf06 in WebCore::ResourceHandle::create (request=@0xbf896620,
> > client=0x8442360, frame=0x822b630, defersLoading=false,
> > mightDownloadFromHandle=false) at
> > ../../platform/network/ResourceHandle.cpp:43
> > #6  0xb6d23ccc in WebCore::ResourceLoader::load (this=0x8442360,
> > r=@0xbf8968f8) at ../../loader/ResourceLoader.cpp:116
> > #7  0xb6d26b40 in WebCore::SubresourceLoader::load (this=0x8442360,
> > r=@0xbf8968f8) at ../../loader/SubresourceLoader.cpp:81
> > #8  0xb6d271ba in WebCore::SubresourceLoader::create (frame=0x822b630,
> > client=0xb70918b8, request=@0xbf896a60) at
> > ../../loader/SubresourceLoader.cpp:119
> > #9  0xb6d1830d in WebCore::Loader::servePendingRequests
> > (this=0xb70918b8) at ../../loader/loader.cpp:88
> > #10 0xb6d19528 in WebCore::Loader::load (this=0xb70918b8, dl=0x8290fc0,
> > object=0x845b2c8, incremental=true) at ../../loader/loader.cpp:63
> > #11 0xb6cdeb8e in CachedImage (this=0x845b2c8, docLoader=0x8290fc0,
> > url=@0xbf896e94, cachePolicy=WebCore::CachePolicyVerify, _expireDate=0)
> > at ../../loader/CachedImage.cpp:63
> > #12 0xb6cdc879 in WebCore::Cache::requestResource (this=0xb70918a0,
> > docLoader=0x8290fc0, type=WebCore::CachedResource::ImageResource,
> > url=@0xbf897020, expireDate=0, charset=0x0) at ../../loader/Cache.cpp:65
> > #13 0xb6ce4521 in WebCore::DocLoader::requestResource (this=0x8290fc0,
> > type=WebCore::CachedResource::ImageResource, url=@0xbf897178,
> > charset=0x0, skipCanLoadCheck=false) at ../../loader/DocLoader.cpp:134
> > #14 0xb6ce4734 in WebCore::DocLoader::requestImage (this=0x8290fc0,
> > url=@0xbf897178) at ../../loader/DocLoader.cpp:88
> > #15 0xb6c3b614 in WebCore::HTMLImageLoader::updateFromElement
> > (this=0x845beac) at ../../html/HTMLImageLoader.cpp:102
> > #16 0xb6c39b2e in WebCore::HTMLImageElement::parseMappedAttribute
> > (this=0x845be40, attr=0x8459dc0) at ../../html/HTMLImageElement.cpp:95
> > #17 0xb6b62ffe in WebCore::StyledElement::attributeChanged
> > (this=0x845be40, attr=0x8459dc0, preserveDecls=false) at
> > ../../dom/StyledElement.cpp:178
> > #18 0xb6b36522 in WebCore::Element::setAttributeMap (this=0x845be40,
> > list=0x843d850) at ../../dom/Element.cpp:437
> > #19 0xb6c5dc7c in WebCore::HTMLParser::parseToken (this=0x8297030,
> > t=0x8296af4) at ../../html/HTMLParser.cpp:208
> > #20 0xb6c7a88f in WebCore::HTMLTokenizer::processToken (this=0x8296ae0)
> > at ../../html/HTMLTokenizer.cpp:1590
> > #21 0xb6c80133 in WebCore::HTMLTokenizer::parseTag (this=0x8296ae0,
> > src=@0x8296fe0, state={static EntityShift = 4, m_bits = 1}) at
> > ../../html/HTMLTokenizer.cpp:1163
> > #22 0xb6c82cba in WebCore::HTMLTokenizer::write (this=0x8296ae0,
> > str=@0xbf89752c, appendData=true) at ../../html/HTMLTokenizer.cpp:1389
> > #23 0xb6cf1ed8 in WebCore::FrameLoader::write (this=0x822b2c0,
> > str=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > len=4904, flush=false) at ../../loader/FrameLoader.cpp:896
> > #24 0xb6cf22ec in WebCore::FrameLoader::addData (this=0x822b2c0,
> > bytes=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904) at ../../loader/FrameLoader.cpp:1516
> > #25 0xb6cec96c in WebCore::FrameLoader::committedLoad (this=0x822b2c0,
> > loader=0x8255868, data=0x827da10 "<html><head><meta
> > http-equiv=\"content-type\" content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904) at ../../loader/FrameLoader.cpp:2944
> > #26 0xb6ce6931 in WebCore::DocumentLoader::commitLoad (this=0x8255868,
> > data=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904) at ../../loader/DocumentLoader.cpp:320
> > #27 0xb6ce6a35 in WebCore::DocumentLoader::receivedData (this=0x8255868,
> > data=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904) at ../../loader/DocumentLoader.cpp:332
> > #28 0xb6ced383 in WebCore::FrameLoader::receivedData (this=0x822b2c0,
> > data=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904) at ../../loader/FrameLoader.cpp:1911
> > #29 0xb6d1ac06 in WebCore::MainResourceLoader::addData (this=0x825ba78,
> > data=0x827da10 "<html><head><meta http-equiv=\"content-type\"
> > content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904, allAtOnce=false) at ../../loader/MainResourceLoader.cpp:133
> > #30 0xb6d218d1 in WebCore::ResourceLoader::didReceiveData
> > (this=0x825ba78, data=0x827da10 "<html><head><meta
> > http-equiv=\"content-type\" content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904, lengthReceived=0, allAtOnce=false) at
> > ../../loader/ResourceLoader.cpp:206
> > #31 0xb6d1bc31 in WebCore::MainResourceLoader::didReceiveData
> > (this=0x825ba78, data=0x827da10 "<html><head><meta
> > http-equiv=\"content-type\" content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904, lengthReceived=0, allAtOnce=false) at
> > ../../loader/MainResourceLoader.cpp:291
> > #32 0xb6d20fa8 in WebCore::ResourceLoader::didReceiveData
> > (this=0x825ba78, data=0x827da10 "<html><head><meta
> > http-equiv=\"content-type\" content=\"text/html;
> > charset=UTF-8\"><title>Google</title><style><!--\nbody,td,a,p,.h{font-family:arial,sans-serif}\n.h{font-size:20px}\n.h{color:#3366cc}\n.q{col"...,
> > length=4904, lengthReceived=0) at ../../loader/ResourceLoader.cpp:318
> > #33 0xb6ea1110 in writeCallback (ptr=0x827da10, size=1, nmemb=4904,
> > obj=0x823b028) at ../../platform/network/gdk/ResourceHandleManager.cpp:80
> > #34 0xb73417d0 in curl_slist_free_all () from /usr/lib/libcurl.so.3
> > #35 0xb735a951 in curl_multi_init () from /usr/lib/libcurl.so.3
> > #36 0xb735aaf2 in curl_multi_init () from /usr/lib/libcurl.so.3
> > #37 0xb73563f9 in curl_mvsnprintf () from /usr/lib/libcurl.so.3
> > #38 0xb735970d in curl_multi_timeout () from /usr/lib/libcurl.so.3
> > #39 0xb7359d94 in curl_multi_perform () from /usr/lib/libcurl.so.3
> > #40 0xb6ea1302 in WebCore::ResourceHandleManager::downloadTimerCallback
> > (this=0x825c5a8, timer=0x825c5a8) at
> > ../../platform/network/gdk/ResourceHandleManager.cpp:120
> > #41 0xb6ea23db in WebCore::Timer<WebCore::ResourceHandleManager>::fired
> > (this=0x825c5a8) at ../../platform/Timer.h:96
> > #42 0xb6d90dc4 in WebCore::TimerBase::fireTimers
> > (fireTime=1172200670.95, firingTimers=@0xbf897bec) at
> > ../../platform/Timer.cpp:336
> > #43 0xb6d90ebf in WebCore::TimerBase::sharedTimerFired () at
> > ../../platform/Timer.cpp:353
> > #44 0xb6e9c408 in WebCore::WebKitTimer::Notify (this=0x826ed58) at
> > ../../platform/wx/wxSharedTimer.cpp:62
> > #45 0xb6584f72 in timeout_callback (data=0x826ed58) at
> > ../src/gtk/timer.cpp:43
> > #46 0xb59b8dd6 in g_source_get_current_time () from
> > /usr/lib/libglib-2.0.so.0
> > #47 0xb59b8802 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
> > #48 0xb59bb7df in g_main_context_check () from /usr/lib/libglib-2.0.so.0
> > #49 0xb59bbb89 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
> > #50 0xb5e18574 in IA__gtk_main () at gtkmain.c:1024
> > #51 0xb657a3bb in wxEventLoop::Run (this=0x8279088) at
> > ../src/gtk/evtloop.cpp:76
> > #52 0xb6625774 in wxAppBase::MainLoop (this=0x809c098) at
> > ../src/common/appcmn.cpp:308
> > #53 0xb66250bd in wxAppBase::OnRun (this=0x809c098) at
> > ../src/common/appcmn.cpp:363
> > #54 0xb630023c in wxEntry (argc=@0xb6407a2c, argv=0x808a758) at
> > ../src/common/init.cpp:449
> > #55 0xb6300307 in wxEntry (argc=@0xbf897ee0, argv=0xbf897f64) at
> > ../src/common/init.cpp:461
> > #56 0x080620e0 in main (argc=Cannot access memory at address 0x0
> > ) at webkittest.cpp:151
> > (gdb)
> >
> >
> >
> > --
> > Robin Dunn
> > Software Craftsman
> > http://wxPython.org  Java give you jitters?  Relax with wxPython!
> >
> >
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