Le mercredi 04 janvier 2006 à 18:19 +0100, Gilles Chanteperdrix a écrit : > Stelian Pop wrote: > > Before hanging, sometimes it just prints: > > Unable to handle kernel NULL pointer dereference at virtual address > 0000004d > > > > Sometimes the oops is more complete (note that sometimes it also hangs in > the middle of > > the printout): > > Unable to handle kernel NULL pointer dereference at virtual address > 0000004d > > pgd = c0004000 > > [0000004d] *pgd=00000000 > > Internal error: Oops: 817 [#1] > > Modules linked in: xeno_timerbench > > CPU: 0 > > PC is at xnpod_schedule+0x6b4/0x7f0 > > LR is at xnpod_schedule+0x54c/0x7f0 > > pc : [<c0056cc4>] lr : [<c0056b5c>] Not tainted > > sp : c7d41830 ip : c79e8044 fp : c7d41860 > > r10: c0283c2c r9 : c0282 > > > > Does this rings a bell to someone ? > > Not much, but two remarks: > - last summer, there use to be such a problem on x86 because of some > wrong FPU switch. So, is FPU enabled ? Are you compiling latency with > -msoft-float ?
Yes, everything is soft float. > When announcing the ARM Adeos port, you told us that not all > exceptions were trapped by the Adeos patch. If one of the FPU > exceptions is not trapped, it would explain why we do not get the > usual message "Invalid use of FPU at ..." before the oops. Time has passed and the exceptions are now trapped. > - as far as I know, xnpod_schedule never recurses, so, there is little > chance for PC and LR to be both in xnpod_schedule. If I am not wrong, > it means that you will have to have a look at the disassembly (sorry) > and see in really what functions the bugs happen. Sometimes the -r and > -S option of objdump help... I'll take a look. Stelian. -- Stelian Pop <[EMAIL PROTECTED]>