On Wednesday 11 February 2009, Stanislaw Gruszka wrote: > Hello. > > I entered a problem with double decreasing module reference counter > where it become "negative", here is the usage scenario: > > # modprobe at91_ide > # modprobe ide_gd_mod > # lsmod > Module Size Used by Not tainted > ide_gd_mod 22948 0 > at91_ide 4672 0 > ide_core 77020 2 ide_gd_mod,at91_ide > # rmmod ide_gd_mod > # lsmod > Module Size Used by Not tainted > at91_ide 4672 4294967295 > ide_core 77020 1 at91_ide > > Note when I first remove at91_ide module and then ide_gd_mod > everyting is ok. > > I tired to debug issue and I did not found any suspicious in at91_ide. > I think probable reason is double free in ide-gd.c . Here is patch with > workaround (or maybe it is a real fix, but I'm not sure): > > diff --git a/drivers/ide/ide-gd.c b/drivers/ide/ide-gd.c > index 7857b20..31ae04e 100644 > --- a/drivers/ide/ide-gd.c > +++ b/drivers/ide/ide-gd.c > @@ -70,8 +70,6 @@ static void ide_gd_remove(ide_drive_t *drive) > del_gendisk(g); > > drive->disk_ops->flush(drive); > - > - ide_disk_put(idkp); > } > > static void ide_disk_release(struct kref *kref) > > If this patch is ok, maybe similar things need to be done also in ide-cd and > perhaps other device type modules. Seems like ide_device_put() needs the same module_refcount() check that is present in scsi_device_put() so removal of device driver won't trigger a spurious module_put() on a host driver? Thanks, Bart -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
