On Wed, Oct 17, 2007 at 10:27:47AM -0600, Matthew Wilcox wrote: > On Wed, Oct 17, 2007 at 10:53:06AM -0400, Tony Battersby wrote: > > After looking at it carefully, this is true of pci_map_mem, but not > > pci_unmap_mem. pci_unmap_mem can be called from both ->detect and > > ->release. io_request_lock is held in ->detect but not in ->release. > > So, your patch locks up the system on module unload. > > My mistake. I should have checked the iorl was held over ->release too. > > This is a pretty ugly patch, but I think the three alternatives are > worse: > > - Drop the iorl at the beginning of ->detect and reacquire it at exit. > We don't know what else the iorl might be protecting. Probably > nothing, but I don't want to audit it. > - Convert sym2 back to old error handling so the midlayer doesn't > acquire the iorl for us in ->detect. > - Acquire the iorl in ->release. We might deadlock on something. > > So, sure, apply this patch. Matthew, Sincere thanks for your help and review. I'll apply this patch in 2.4.36-pre2 and in next 2.4.35.X. An ugly fix is clearly better than a massive change at this stage. Natalie, if you want, you can close the bug right now, I've queued the patch for both branches. Best regards, Willy - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
