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</o:shapelayout></xml><![endif]--></head><body lang=FR link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>We can put aside Java Memory Leak.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>I downgraded to kernel 3.10.0-957.27.2.el7.x86_64, there are no more crashes. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The bug comes from ‘futex‘ syscall. What can causes that bug and how can i investigate ?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Christophe Dumont<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Ligne directe : 0476842574<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Arial",sans-serif;color:black'><img width=171 height=101 style='width:1.7812in;height:1.052in' id="Image_x0020_1" src="cid:image001.png@01D584CF.DC7C5490" alt="Description : Logo_Yoni_Groupe_small"></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>De :</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Valdis Kletnieks <valdis@vt.edu> <b>De la part de</b> Valdis Kletnieks<br><b>Envoyé :</b> mercredi 16 octobre 2019 16:17<br><b>À :</b> Christophe DUMONT <Christophe.DUMONT@yoni.fr><br><b>Cc :</b> kernelnewbies@kernelnewbies.org<br><b>Objet :</b> Re: Kernel Panic<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p><span style='font-family:"Calibri",sans-serif'>On Wed, 16 Oct 2019 07:34:01 -0000, Christophe DUMONT said:</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>> What made me think about a memory leak is the message : Java Not Tainted 3.10.0-1062.1.1.el7.x86_64.=20</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>That just tells you that the currently executing process was java.</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>It says nothing at all about a memory leak, and as I already mentioned, if Java</span> <br><span style='font-family:"Calibri",sans-serif'>was leaking memory, it would almost certainly have been leaking memory on a</span> <br><span style='font-family:"Calibri",sans-serif'>previous kernel.</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>The important part almost always isn't the running process, it's the kernel</span> <br><span style='font-family:"Calibri",sans-serif'>stack traceback, which in this case has 'futex' scribbled *all* over it.</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>General rule of thumb:</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>If you get more than one crash that has a similar traceback that points at a</span> <br><span style='font-family:"Calibri",sans-serif'>specific syscall, or file system driver, etc, the bug is almost guaranteed to</span> <br><span style='font-family:"Calibri",sans-serif'>be in that code.</span> <o:p></o:p></p><p><span style='font-family:"Calibri",sans-serif'>If you get a rash of crashes with *different* tracebacks, you probably have</span> <br><span style='font-family:"Calibri",sans-serif'>some other code that's overlaying memory.</span> <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>