Messages in this thread | | | Date | Fri, 6 Jan 2012 15:43:55 -0200 | From | Thadeu Lima de Souza Cascardo <> | Subject | Re: [PATCH] rds_rdma: don't assume infiniband device is PCI |
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On Fri, Jan 06, 2012 at 01:57:50PM -0200, Thadeu Lima de Souza Cascardo wrote: > On Thu, Jan 05, 2012 at 03:05:24PM -0200, Thadeu Lima de Souza Cascardo wrote: > > > ----- Original Message ----- > > > From: cascardo@linux.vnet.ibm.com > > > To: venkat.x.venkatsubra@oracle.com > > > Cc: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, cascardo@linux.vnet.ibm.com, dledford@redhat.com, Jes.Sorensen@redhat.com, rds-devel@oss.oracle.com > > > Sent: Wednesday, January 4, 2012 4:03:42 PM GMT -06:00 US/Canada Central > > > Subject: [PATCH] rds_rdma: don't assume infiniband device is PCI > > > > > > RDS code assumes that the struct ib_device dma_device member, which is a > > > pointer, points to a struct device embedded in a struct pci_dev. > > > > > > This is not the case for ehca, for example, which is a OF driver, and > > > makes dma_device point to a struct device embedded in a struct > > > platform_device. > > > > > > This will make the system crash when rds_rdma is loaded in a system > > > with ehca, since it will try to access the bus member of a non-existent > > > struct pci_dev. > > > > > > The only reason rds_rdma uses the struct pci_dev is to get the NUMA node > > > the device is attached to. Using dev_to_node for that is much better, > > > since it won't assume which bus the infiniband is attached to. > > > > > > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> > > > Cc: dledford@redhat.com > > > Cc: Jes.Sorensen@redhat.com > > > Cc: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com> > > > Cc: rds-devel@oss.oracle.com > > > --- > > > net/rds/ib.h | 3 +-- > > > 1 files changed, 1 insertions(+), 2 deletions(-) > > > > > > diff --git a/net/rds/ib.h b/net/rds/ib.h > > > index edfaaaf..8d2b3d5 100644 > > > --- a/net/rds/ib.h > > > +++ b/net/rds/ib.h > > > @@ -186,8 +186,7 @@ struct rds_ib_device { > > > struct work_struct free_work; > > > }; > > > > > > -#define pcidev_to_node(pcidev) pcibus_to_node(pcidev->bus) > > > -#define ibdev_to_node(ibdev) pcidev_to_node(to_pci_dev(ibdev->dma_device)) > > > +#define ibdev_to_node(ibdev) dev_to_node(ibdev->dma_device) > > > #define rdsibdev_to_node(rdsibdev) ibdev_to_node(rdsibdev->dev) > > > > > > /* bits for i_ack_flags */ > > > -- > > > 1.7.4.4 > > > > > > > On Thu, Jan 05, 2012 at 08:56:34AM -0800, Venkat Venkatsubra wrote: > > > Hi Cascardo, > > > > > > Your changes look good to me. > > > But our latest code doesn't use this rdsibdev_to_node macro anywhere. > > > Checking with the people in my group who know the history of the NUMA feature. > > > Trying to find out if the call to kzalloc_node() can be replaced by kzalloc(). > > > In which case this macro can be removed. > > > > > > I will keep you posted. > > > > > > Venkat > > > > > > > Hi, Venkat. > > > > Do you have any public tree where we can track the last changes in RDS? > > Note that I have changed ibsdev_to_node, which rdsibdev_to_node makes > > use of. Anyway, replacing kzalloc_node with kzalloc has crossed my mind, > > but since I was not sure if this would affect latency of RDS in any use > > cases, I kept that and used a better function to get the node from the > > device. And we have dev_to_node since 2.6.20, so it should not be a > > problem to use it. > > > > If possible, keep everyone copied and avoid top posting. > > > > Regards. > > Cascardo. > > Just to make it clean, ibdev_to_node is used in Linus' tree and > next/master as of today and this patch fixes a real oops. I should have > probably added the stack trace in the log message. For completion, here > it is, running 3.2.0-rc7-00039-g89307ba: > > NET: Registered protocol family 21 > Registered RDS/iwarp transport > Unable to handle kernel paging request for data at address 0x00000088 > Faulting instruction address: 0xc0000000000336d0 > cpu 0x6: Vector: 300 (Data Access) at [c0000000ddd837e0] > pc: c0000000000336d0: .pcibus_to_node+0x0/0x10 > lr: d000000004590de0: .rds_ib_add_one+0x100/0x360 [rds_rdma] > sp: c0000000ddd83a60 > msr: 8000000000009032 > dar: 88 > dsisr: 40000000 > current = 0xc0000000ee6c0000 > paca = 0xc000000006c32d00 > pid = 8574, comm = modprobe > enter ? for help > [link register ] d000000004590de0 .rds_ib_add_one+0x100/0x360 > [rds_rdma] > [c0000000ddd83a60] d000000004590d88 .rds_ib_add_one+0xa8/0x360 > [rds_rdma] (unreliable) > [c0000000ddd83b10] d000000003195240 .ib_register_client+0xc0/0x120 > [ib_core] > [c0000000ddd83bb0] d00000000459074c .rds_ib_init+0x2c/0xf0 [rds_rdma] > [c0000000ddd83c30] d000000004590144 .rds_rdma_init+0xe4/0x180 [rds_rdma] > [c0000000ddd83cd0] c00000000000aa54 .do_one_initcall+0x64/0x1e0 > [c0000000ddd83d90] c0000000000d359c .SyS_init_module+0xcc/0x220 > [c0000000ddd83e30] c0000000000097e4 syscall_exit+0x0/0x40 > --- Exception: c00 (System Call) at 00000fff7dc3d3d8 > SP (fffe87eeeb0) is in userspace > > Regards. > Cascardo. >
David,
The References was broken by Venkat email, so patchwork is not catching up the new messages in the thread. At least, that's what I expect it uses. So, I am sending this message with a fixed References. Sorry for that.
Regards. Cascardo.
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