Hi Borislav, Borislav Petkov wrote: > Hi, > > On Thu, Apr 16, 2009 at 12:45:31AM +0200, Helge Deller wrote: >> With 2.6.30-rc2 I face a kernel crash on the 32bit hppa architecture >> due to ide-cd when udev creates the device nodes at startup: >> >> Kernel Fault: Code=26 regs=8ed34c40 (Addr=00000024) >> IASQ: 00000000 00000000 IAOQ: 1034b5ac 1034b5b0 >> IIR: 4ab30048 ISR: 00000000 IOR: 00000024 >> CPU: 0 CR30: 8ed34000 CR31: ffff55ff >> ORIG_R28: 00000000 >> IAOQ[0]: ide_complete_rq+0x2c/0x70 >> IAOQ[1]: ide_complete_rq+0x30/0x70 >> RP(r2): cdrom_newpc_intr+0x178/0x46c >> Backtrace: >> [<1035c608>] cdrom_newpc_intr+0x178/0x46c >> [<1034c494>] ide_intr+0x1b0/0x214 >> [<1016d284>] handle_IRQ_event+0x70/0x150 >> [<1016d4b0>] __do_IRQ+0x14c/0x1cc >> [<102f7864>] superio_interrupt+0x88/0xbc >> [<1016d284>] handle_IRQ_event+0x70/0x150 >> [<1016d4b0>] __do_IRQ+0x14c/0x1cc >> [<10112efc>] do_cpu_irq_mask+0x9c/0xd0 >> [<10116068>] intr_return+0x0/0x4 >> >> This crash seems to happen due to an uninitialized variable "rc". >> The compiler even warns about that: >> CC drivers/ide/ide-cd.o >> /mnt/sda4/home/cvs/parisc/git-kernel/linus-linux-2.6/drivers/ide/ide-cd.c: In function `cdrom_newpc_intr': >> /mnt/sda4/home/cvs/parisc/git-kernel/linus-linux-2.6/drivers/ide/ide-cd.c:612: warning: `rc' might be used uninitialized in this function > > can you do > > gdb ./vmlinux > > and then > > (gdb) l *(cdrom_newpc_intr+0x178) > > I think I have a suspect but I want to be sure. In order to do that > you'll need a debug kernel (set CONFIG_DEBUG_INFO to 'y' in your > .config). In case the oops above is not from a debug kernel, can you > catch it again and _then_ do the gdb thing since the offset of 0x178 is > most probably going to change. In that case, you have to do > > (gdb) l *(cdrom_newpc_intr+NEW_OFFSET_FROM_THE_OOPS) I tried to build a kernel with CONFIG_DEBUG_INFO. There are two problem with that, because I'm cross-compiling: a) I don't have a cross-gdb (but I could use addr2line instead though) b) the resulting kernel is becoming too big and won't link/boot: ... SYSMAP System.map SYSMAP .tmp_System.map /sbin/palo -f /mnt/sda4/home/cvs/parisc/git-kernel/linus-linux-2.6-32bit/palo.conf palo version 1.14 deller@p100 Fri Jul 28 22:55:11 CEST 2006 ELF32 executable ipl: addr 2048 size 36864 entry 0x0 ko 0x0 ksz 0 k64o 0x0 k64sz 0 rdo 0 rdsz 0 <> Your 32-bit-kernel is too big for your F0 partition make[3]: *** [palo] Error 2 I could now just try to look into the assembly by hand and try to find which line produces the problem. But reading hppa assembly code for such a big function is not very easy though. So, my question would be: If you have an idea where the problem is, maybe you have a patch for me to try? That would simplify the whole thing for me a lot, as just compiling/run-testing is much easier for me. Best regards, Helge BTW, even with my patch ATAPI CDROM accesses don't work with the current kernel... -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
