K. Y. Srinivasan, On Wed, Dec 10, 2014 at 05:13:00PM -0800, K. Y. Srinivasan wrote: > Correctly compute the local (gpadl) handle.
This description is still too sparse for me. How was it computed before and why was this incorrect? Pretend like you are trying to explain your patch to someone who has no idea what you did. > I would like to thank Michael Brown <mc...@ipxe.org> for seeing this bug. > > Signed-off-by: K. Y. Srinivasan <k...@microsoft.com> > Reported-by: Michael Brown <mc...@ipxe.org> > --- > Changes in V2: Added the Reported-by tag. > Changes in V3: Cleaned up the commit log. > > drivers/hv/channel.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c > index 433f72a..c76ffbe 100644 > --- a/drivers/hv/channel.c > +++ b/drivers/hv/channel.c > @@ -366,8 +366,8 @@ int vmbus_establish_gpadl(struct vmbus_channel *channel, > void *kbuffer, > unsigned long flags; > int ret = 0; > > - next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle); > - atomic_inc(&vmbus_connection.next_gpadl_handle); > + next_gpadl_handle = > + (atomic_inc_return(&vmbus_connection.next_gpadl_handle) - 1); > Tell me if I understand this correctly. Before it read the handle and incremented it. y = x + 1 Now it reads the handle, increments it, then decrements it. y = (x + 1) - 1 = x > ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount); > if (ret) > -- > 1.7.4.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- - Jeremiah Mahler -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
