On 07/20/2010 06:21 PM, Hidetoshi Seto wrote: > With v2.6.35-rc5, my x86-64 server doesn't boot but reports a > Completer Abort on lpfc card. > > The result of git-bisect is: > 6175ddf06b6172046a329e3abfd9c901a43efd2e is the first bad commit > commit 6175ddf06b6172046a329e3abfd9c901a43efd2e > Author: Brian Gerst <brgerst@xxxxxxxxx> > Date: Fri Feb 5 09:37:07 2010 -0500 > x86: Clean up mem*io functions. > > What I found are: > - memcpy for 64bit uses movq if count >= 64 (arch/x86/lib/memcpy_64.S) > - memcpy_toio and memcpy_fromio have changed to use this memcpy by > the above commit. > - my debug shows that lpfc calls memcpy_toio with not-qword-aligned > addresses and count >= 64, e.g.: > memcpy_toio(0xffffc900118de004, 0xffff88047293d614, 124); > and it seems that it comes from: > [drivers/scsi/lpfc/lpfc_sli.c] > 4929 /* First copy mbox command data to HBA SLIM, skip past first > 4930 word */ > 4931 to_slim = phba->MBslimaddr + sizeof (uint32_t); > 4932 lpfc_memcpy_to_slim(to_slim, &mb->un.varWords[0], > 4933 MAILBOX_CMD_SIZE - sizeof (uint32_t)); > > Still I'm not sure what is wrong in software or hardware, however > I suppose that qword access to iomem is not always safe, so it will > be OK to back to use __inline_memcpy which uses movsl. > > I confirmed that my server (w/ lpfc) boots with 35-rc5 + this patch. > > Signed-off-by: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx> A driver should not use the memcpy-like instructions if it isn't set up to act as memory (meaning it can handle arbitrary byte enables.) The function it should be using is called, fairly counterintuitively, __iowrite32_copy(). It really should be called memcpy_toio32() or something similar. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- 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
