• Helge Deller's avatar
    ide-cd: fix kernel crash on hppa regression · a1f9a89c
    Helge Deller authored
    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
     [<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
    After applying the trivial patch below, which just initializes 
    the variable to zero, the kernel doesn't crash any longer:
    Starting the hotplug events dispatcher: udevd.
    Synthesizing the initial hotplug events...
    hda: command error: status=0x51 { DriveReady SeekComplete Error }
    hda: command error: error=0x54 <3>{ AbortedCommand LastFailedSense=0x05 }
    ide: failed opcode was: unknown
    Signed-off-by: default avatarHelge Deller <deller@gmx.de>
    Acked-by: default avatarBorislav Petkov <petkovbb@gmail.com>
    Cc: Linus <torvalds@linux-foundation.org>
    Cc: Kyle McMartin <kyle@mcmartin.ca>
    Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
    Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
ide-cd.c 47.1 KB