On Fri, 2014-10-24 at 13:13 +0800, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > This is a note to let you know that I've just added the patch titled > > powerpc/powernv: Fix endian bug in LPC bus debugfs accessors > > to the 3.17-stable tree which can be found at: > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary Hi Greg ! Please take it out, it's actually bogus :-( (And from 3.16 too and any other stable queue it might have landed in) Michael, can you send a revert to Linus please ? The original code was fine, I think the bug was actually in the userspace tool I was using (don't worry, nothing on the field uses that interface... yet and I can still fix the tool). Sorry about that. Ben. > The filename of the patch is: > powerpc-powernv-fix-endian-bug-in-lpc-bus-debugfs-accessors.patch > and it can be found in the queue-3.17 subdirectory. > > If you, or anyone else, feels it should not be added to the stable tree, > please let <stable@xxxxxxxxxxxxxxx> know about it. > > > >From bf7588a0859580a45c63cb082825d77c13eca357 Mon Sep 17 00:00:00 2001 > From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Date: Fri, 3 Oct 2014 17:12:25 +1000 > Subject: powerpc/powernv: Fix endian bug in LPC bus debugfs accessors > > From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > > commit bf7588a0859580a45c63cb082825d77c13eca357 upstream. > > When reading from the LPC, the OPAL FW calls return the value via pointer > to a uint32_t which is always returned big endian. Our internal inb/outb > implementation byteswaps that fine but our debugfs code is still broken. > > Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > --- > arch/powerpc/platforms/powernv/opal-lpc.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > --- a/arch/powerpc/platforms/powernv/opal-lpc.c > +++ b/arch/powerpc/platforms/powernv/opal-lpc.c > @@ -191,6 +191,7 @@ static ssize_t lpc_debug_read(struct fil > { > struct lpc_debugfs_entry *lpc = filp->private_data; > u32 data, pos, len, todo; > + __be32 bedata; > int rc; > > if (!access_ok(VERIFY_WRITE, ubuf, count)) > @@ -213,9 +214,10 @@ static ssize_t lpc_debug_read(struct fil > len = 2; > } > rc = opal_lpc_read(opal_lpc_chip_id, lpc->lpc_type, pos, > - &data, len); > + &bedata, len); > if (rc) > return -ENXIO; > + data = be32_to_cpu(bedata); > switch(len) { > case 4: > rc = __put_user((u32)data, (u32 __user *)ubuf); > > > Patches currently in stable-queue which might be from benh@xxxxxxxxxxxxxxxxxxx are > > queue-3.17/powerpc-powernv-fix-endian-bug-in-lpc-bus-debugfs-accessors.patch > queue-3.17/powerpc-iommu-ddw-fix-endianness.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html