56116 2011-03-10 10:05:47 -0800 [Qt][WK2] Need a way to debug the web process after the UI process dies 2011-03-18 15:25:04 -0700 1 1 1 Unclassified WebKit WebKit2 528+ (Nightly build) PC Linux RESOLVED FIXED Qt, QtTriaged P5 Normal --- 1 kbalazs webkit-unassigned benjamin commit-queue oldest_to_newest 365270 0 kbalazs 2011-03-10 10:05:47 -0800 We disallow the web process to live out it's parent dead: prctl(PR_SET_PDEATHSIG, SIGKILL) For developers it could be useful to be able to debug a web process that's parent has already died. Another debugging issue with the current setup is that when one attach to the web process via 'set-follow-fork-mode child' and press ^C to interrupt the web process it terminates immediately. 365282 1 85343 kbalazs 2011-03-10 10:17:26 -0800 Created attachment 85343 Patch 366919 2 benjamin 2011-03-14 03:35:43 -0700 Out of curiosity, what was the use case? 367058 3 kbalazs 2011-03-14 10:45:49 -0700 (In reply to comment #2) > Out of curiosity, what was the use case? (gdb) set follow-fork-mode child (gdb) r Starting program: /home/balazs/master_clean/WebKitBuild/Debug/bin/MiniBrowser [Thread debugging using libthread_db enabled] [New Thread 0x7fffebf45710 (LWP 28471)] [New Thread 0x7fffeb744710 (LWP 28472)] [New process 28473] [Thread debugging using libthread_db enabled] process 28473 is executing new program: /home/balazs/master_clean/WebKitBuild/Debug/bin/QtWebProcess [Thread debugging using libthread_db enabled] [New Thread 0x7fffebf45710 (LWP 28571)] [New Thread 0x7fffea7f2710 (LWP 28572)] ^C[Thread 0x7fffea7f2710 (LWP 28572) exited] [Thread 0x7fffebf45710 (LWP 28571) exited] Program terminated with signal SIGKILL, Killed. The program no longer exists. With the patch via ^C the debugger can normally interrupt execution. 367083 4 benjamin 2011-03-14 11:25:07 -0700 I understand that can happen, but what is the use case for debugging the Web process without having the UI process? It is not like anything will happen and the memory dump seems just as useful. 367342 5 kbalazs 2011-03-14 16:40:19 -0700 (In reply to comment #4) > I understand that can happen, but what is the use case for debugging the Web process without having the UI process? It is not like anything will happen and the memory dump seems just as useful. Oh, I see. Yes, maybe this possibility is not really valuable but it is really annoying that one cannot interrupt the execution while debugging. It's not clear to me why the UI process exiting in that case, maybe gdb is not compatible with our usage of prctl. The target of the patch is to work around this behavior. 369726 6 kbalazs 2011-03-18 10:59:05 -0700 ping 369764 7 85343 benjamin 2011-03-18 11:51:45 -0700 Comment on attachment 85343 Patch Ok, read your comments again, and I finally understand why I don't have the problem. I only gdb the QtWebProcess, by attaching to it. Your use case make sense, I did not fully understand it. Please document QT_WEBKIT_KEEP_ALIVE_WEB_PROCESS on the Wiki. 369842 8 commit-queue 2011-03-18 13:55:17 -0700 The commit-queue encountered the following flaky tests while processing attachment 85343: webarchive/test-link-rel-icon.html bug 56663 (author: ddkilzer@webkit.org) The commit-queue is continuing to process your patch. 369843 9 85343 commit-queue 2011-03-18 13:57:28 -0700 Comment on attachment 85343 Patch Clearing flags on attachment: 85343 Committed r81507: <http://trac.webkit.org/changeset/81507> 369844 10 commit-queue 2011-03-18 13:57:33 -0700 All reviewed patches have been landed. Closing bug. 369954 11 commit-queue 2011-03-18 15:25:04 -0700 The commit-queue encountered the following flaky tests while processing attachment 85343: webarchive/test-link-rel-icon.html bug 56663 (author: ddkilzer@webkit.org) The commit-queue is continuing to process your patch. 85343 2011-03-10 10:17:26 -0800 2011-03-18 13:57:27 -0700 Patch bug-56116-20110310181725.patch text/plain 1710 kbalazs U3VidmVyc2lvbiBSZXZpc2lvbjogODA3MjEKZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJLaXQyL0No YW5nZUxvZyBiL1NvdXJjZS9XZWJLaXQyL0NoYW5nZUxvZwppbmRleCAzNTAwMDNkMDRjZTUwZTQw N2Q3Yjg1ZDU5NzA4MThmZGNiNWE3NmMzLi41ZjlmZWRkOTYzNTIzNDRkZDcwZmU4N2M3MDg3NDI3 NGNiNGE1ZDNkIDEwMDY0NAotLS0gYS9Tb3VyY2UvV2ViS2l0Mi9DaGFuZ2VMb2cKKysrIGIvU291 cmNlL1dlYktpdDIvQ2hhbmdlTG9nCkBAIC0yLDYgKzIsMjMgQEAKIAogICAgICAgICBSZXZpZXdl ZCBieSBOT0JPRFkgKE9PUFMhKS4KIAorICAgICAgICBbUXRdW1dLMl0gTmVlZCBhIHdheSB0byBk ZWJ1ZyB0aGUgd2ViIHByb2Nlc3MgYWZ0ZXIgdGhlIFVJIHByb2Nlc3MgZGllcworICAgICAgICBo dHRwczovL2J1Z3Mud2Via2l0Lm9yZy9zaG93X2J1Zy5jZ2k/aWQ9NTYxMTYKKworICAgICAgICBB bGxvdyB0aGUgd2ViIHByb2Nlc3MgdG8gb3V0bGl2ZSBpdCdzIHBhcmVudCBwcm9jZXNzCisgICAg ICAgIGluIGRlYnVnIGJ1aWxkcyBpZiB0aGUgUVRfV0VCS0lUX0tFRVBfQUxJVkVfV0VCX1BST0NF U1MKKyAgICAgICAgZW52aXJvbm1lbnQgdmFyaWFibGUgaXMgc2V0LgorCisgICAgICAgICogVUlQ cm9jZXNzL0xhdW5jaGVyL3F0L1Byb2Nlc3NMYXVuY2hlclF0LmNwcDoKKyAgICAgICAgKFdlYktp dDo6UXRXZWJQcm9jZXNzOjpzZXR1cENoaWxkUHJvY2Vzcyk6IFVzZWQgZ2V0ZW52CisgICAgICAg IHNpbmNlIHRoZSBwcmN0bCBjYWxsIGlzIGFscmVhZHkgaW4gYSBMaW51eC1vbmx5IGJsb2NrCisg ICAgICAgIGFuZCB0aGUgaW1wbGVtZW50YXRpb24gaW4gdGhpcyBmaWxlIGlzIGEgY2FuZGlkYXRl CisgICAgICAgIGZvciBzaGFyaW5nIGFjcm9zcyBwb3J0cyBpbiB0aGUgZnV0dXJlLgorCisyMDEx LTAzLTEwICBCYWxhenMgS2VsZW1lbiAgPGtiYWxhenNAd2Via2l0Lm9yZz4KKworICAgICAgICBS ZXZpZXdlZCBieSBOT0JPRFkgKE9PUFMhKS4KKwogICAgICAgICBbV0syXSBIYW5kbGUga2V5Ym9h cmQgYW5kIG1vdXNlIGV2ZW50cyBvbiBYMTEKICAgICAgICAgaHR0cHM6Ly9idWdzLndlYmtpdC5v cmcvc2hvd19idWcuY2dpP2lkPTU2MTAzCiAKZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJLaXQyL1VJ UHJvY2Vzcy9MYXVuY2hlci9xdC9Qcm9jZXNzTGF1bmNoZXJRdC5jcHAgYi9Tb3VyY2UvV2ViS2l0 Mi9VSVByb2Nlc3MvTGF1bmNoZXIvcXQvUHJvY2Vzc0xhdW5jaGVyUXQuY3BwCmluZGV4IDFlN2Ux NGE0ZTgzMTk4OTM2YjJiYzE5MzJmYTljN2M1ZGRlY2JmM2UuLmRiZTNmMTA2ZDE4ZTllZDYzOGQ4 YmJkM2ZlOGU3YWE1YjNkZDAxNzAgMTAwNjQ0Ci0tLSBhL1NvdXJjZS9XZWJLaXQyL1VJUHJvY2Vz cy9MYXVuY2hlci9xdC9Qcm9jZXNzTGF1bmNoZXJRdC5jcHAKKysrIGIvU291cmNlL1dlYktpdDIv VUlQcm9jZXNzL0xhdW5jaGVyL3F0L1Byb2Nlc3NMYXVuY2hlclF0LmNwcApAQCAtNzUsNiArNzUs MTAgQEAgcHJvdGVjdGVkOgogdm9pZCBRdFdlYlByb2Nlc3M6OnNldHVwQ2hpbGRQcm9jZXNzKCkK IHsKICNpZiBkZWZpbmVkIFFfT1NfTElOVVgKKyNpZm5kZWYgTkRFQlVHCisgICAgaWYgKGdldGVu digiUVRfV0VCS0lUX0tFRVBfQUxJVkVfV0VCX1BST0NFU1MiKSkKKyAgICAgICAgcmV0dXJuOwor I2VuZGlmCiAgICAgcHJjdGwoUFJfU0VUX1BERUFUSFNJRywgU0lHS0lMTCk7CiAjZW5kaWYKIH0K