<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=Windows-1252"> <style type="text/css" style="display:none;"></style> </head> <body dir="ltr"> <div id="divtagdefaultwrapper" style="font-size:12pt;color:#000000;font-family:Calibri,Helvetica,sans-serif;" dir="ltr"> If the call to dri_destroy_buffer is delayed until the next eglMakeCurrent, that would also solve the problem (I'm not sure how that would affect other things, though). As long as dri_make_current doesn't compare against a dangling pointer, I'm happy. Johan </div> <hr style="display:inline-block;width:98%" tabindex="-1"> <div id="divRplyFwdMsg" dir="ltr">From: Michel Dänzer <michel@daenzer.net> Sent: Tuesday, April 24, 2018 10:36:00 AM To: Johan Helsing; Marek Olšák Cc: Daniel Stone; pekka.paalanen@collabora.co.uk; ML Mesa-dev Subject: Re: [Mesa-dev] [PATCH] st/dri: Fix dangling pointer to a destroyed dri_drawable <div> </div> </div> <div class="BodyFragment"> <div class="PlainText">On 2018-04-24 09:13 AM, Johan Helsing wrote: > Emil: Your alternative patch won't work because dri_make_current is not necessarily called with NULL after a buffer has been destroyed. > > > The problematic sequence is a pattern we use in QtWayland: > > > //create temporary context > > surface1 = eglCreateWindowSurface() <-- dri_drawable pointer is malloced > > eglMakeCurrent(surface1) <-- ctx->dPriv is set > > > // ... (Get some information about available GL extensions etc) > > > eglDestroySurface(surface1) <-- pointer is freed, ctx->dPriv is now dangling Is this the problem? The memory pointed to by ctx->dPriv shouldn't be freed as long as the surface is bound to the current context? -- Earthling Michel Dänzer | <a href="http://www.amd.com"> http://www.amd.com</a> Libre software enthusiast | Mesa and X developer </div> </div> </body> </html>