Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2016-01-05 Thread Matan Barak
On Thu, Dec 24, 2015 at 9:46 AM, Matan Barak wrote: > On Wed, Dec 23, 2015 at 10:04 PM, Doug Ledford wrote: >> On 10/15/2015 12:58 PM, Hefty, Sean wrote: >> ib_create_ah_from_wc needs to resolve the DMAC in order to create the >> AH (this may result sending an ARP and waiting for response

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-12-23 Thread Matan Barak
On Wed, Dec 23, 2015 at 10:04 PM, Doug Ledford wrote: > On 10/15/2015 12:58 PM, Hefty, Sean wrote: > ib_create_ah_from_wc needs to resolve the DMAC in order to create the > AH (this may result sending an ARP and waiting for response). > CM uses this function (which is now sleepable). >

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-12-23 Thread Doug Ledford
On 10/15/2015 12:58 PM, Hefty, Sean wrote: ib_create_ah_from_wc needs to resolve the DMAC in order to create the AH (this may result sending an ARP and waiting for response). CM uses this function (which is now sleepable). >>> >>> This is a significant change to the CM. The CM calls

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-20 Thread Jason Gunthorpe
On Tue, Oct 20, 2015 at 03:57:54PM +, Hefty, Sean wrote: > > Today, cm assumes paths are reversible primary_path->reversible = 1. > > I can't quickly find a link, but I believe all CM MADs are > reversible, per the spec. But the Linux CM code doesn't always create the reverse CM MAD from the

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-20 Thread Hal Rosenstock
On 10/20/2015 11:57 AM, Hefty, Sean wrote: >> Today, cm assumes paths are reversible primary_path->reversible = 1. > > I can't quickly find a link, but I believe all CM MADs are reversible, per > the spec. Spec citation for this is: C12-5.1.3: All responses generated by the CM protocol shall

RE: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-20 Thread Hefty, Sean
> Today, cm assumes paths are reversible primary_path->reversible = 1. I can't quickly find a link, but I believe all CM MADs are reversible, per the spec.

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-18 Thread Matan Barak
On Thu, Oct 15, 2015 at 7:58 PM, Hefty, Sean wrote: >> >> ib_create_ah_from_wc needs to resolve the DMAC in order to create the >> >> AH (this may result sending an ARP and waiting for response). >> >> CM uses this function (which is now sleepable). >> > >> > This is a significant change to the CM

RE: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-15 Thread Hefty, Sean
> >> ib_create_ah_from_wc needs to resolve the DMAC in order to create the > >> AH (this may result sending an ARP and waiting for response). > >> CM uses this function (which is now sleepable). > > > > This is a significant change to the CM. The CM calls are invoked > assuming that they return re

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-14 Thread Matan Barak
On Tue, Oct 13, 2015 at 7:18 PM, Hefty, Sean wrote: >> On Mon, Oct 12, 2015 at 7:42 PM, Hefty, Sean wrote: >> >> When IP based addressing was introduced, ib_create_ah_from_wc was >> >> changed in order to support a suitable AH. Since this AH should >> >> now contains the DMAC (which isn't a simpl

RE: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-13 Thread Hefty, Sean
> On Mon, Oct 12, 2015 at 7:42 PM, Hefty, Sean wrote: > >> When IP based addressing was introduced, ib_create_ah_from_wc was > >> changed in order to support a suitable AH. Since this AH should > >> now contains the DMAC (which isn't a simple derivative of the GID). > >> In order to find the DMAC,

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-13 Thread Matan Barak
On 10/12/2015 3:59 PM, Devesh Sharma wrote: Looks good, just one doubt inline: Thanks for looking at this patch. On Sun, Oct 11, 2015 at 6:28 PM, Matan Barak wrote: When IP based addressing was introduced, ib_create_ah_from_wc was changed in order to support a suitable AH. Since this AH

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-13 Thread Matan Barak
On Mon, Oct 12, 2015 at 7:42 PM, Hefty, Sean wrote: >> When IP based addressing was introduced, ib_create_ah_from_wc was >> changed in order to support a suitable AH. Since this AH should >> now contains the DMAC (which isn't a simple derivative of the GID). >> In order to find the DMAC, an ARP sh

RE: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-12 Thread Hefty, Sean
> When IP based addressing was introduced, ib_create_ah_from_wc was > changed in order to support a suitable AH. Since this AH should > now contains the DMAC (which isn't a simple derivative of the GID). > In order to find the DMAC, an ARP should sometime be sent. This ARP > is a sleeping context.

Re: [PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-12 Thread Devesh Sharma
Looks good, just one doubt inline: On Sun, Oct 11, 2015 at 6:28 PM, Matan Barak wrote: > When IP based addressing was introduced, ib_create_ah_from_wc was > changed in order to support a suitable AH. Since this AH should > now contains the DMAC (which isn't a simple derivative of the GID). > In o

[PATCH rdma-RC] IB/cm: Fix sleeping while atomic when creating AH from WC

2015-10-11 Thread Matan Barak
When IP based addressing was introduced, ib_create_ah_from_wc was changed in order to support a suitable AH. Since this AH should now contains the DMAC (which isn't a simple derivative of the GID). In order to find the DMAC, an ARP should sometime be sent. This ARP is a sleeping context. ib_create