4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Bart Van Assche <bart.vanass...@wdc.com>

commit 02ee9da347873699603d9ce0112a80b5dd69dea1 upstream.

Eliminate the WARN_ONs that create following two warnings when
registering an rxe device:

WARNING: CPU: 2 PID: 1005 at drivers/infiniband/core/device.c:449 
ib_register_device+0x591/0x640 [ib_core]
CPU: 2 PID: 1005 Comm: run_tests Not tainted 4.15.0-rc4-dbg+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 
1.0.0-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:ib_register_device+0x591/0x640 [ib_core]
Call Trace:
 rxe_register_device+0x3c6/0x470 [rdma_rxe]
 rxe_add+0x543/0x5e0 [rdma_rxe]
 rxe_net_add+0x37/0xb0 [rdma_rxe]
 rxe_param_set_add+0x5a/0x120 [rdma_rxe]
 param_attr_store+0x5e/0xc0
 module_attr_store+0x19/0x30
 sysfs_kf_write+0x3d/0x50
 kernfs_fop_write+0x116/0x1a0
 __vfs_write+0x23/0x120
 vfs_write+0xbe/0x1b0
 SyS_write+0x44/0xa0
 entry_SYSCALL_64_fastpath+0x23/0x9a

WARNING: CPU: 2 PID: 1005 at drivers/infiniband/core/sysfs.c:1279 
ib_device_register_sysfs+0x11d/0x160 [ib_core]
CPU: 2 PID: 1005 Comm: run_tests Tainted: G        W        4.15.0-rc4-dbg+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 
1.0.0-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:ib_device_register_sysfs+0x11d/0x160 [ib_core]
Call Trace:
 ib_register_device+0x3f7/0x640 [ib_core]
 rxe_register_device+0x3c6/0x470 [rdma_rxe]
 rxe_add+0x543/0x5e0 [rdma_rxe]
 rxe_net_add+0x37/0xb0 [rdma_rxe]
 rxe_param_set_add+0x5a/0x120 [rdma_rxe]
 param_attr_store+0x5e/0xc0
 module_attr_store+0x19/0x30
 sysfs_kf_write+0x3d/0x50
 kernfs_fop_write+0x116/0x1a0
 __vfs_write+0x23/0x120
 vfs_write+0xbe/0x1b0
 SyS_write+0x44/0xa0
 entry_SYSCALL_64_fastpath+0x23/0x9a

The code should accept either a parent pointer or a fully specified DMA
specification without producing warnings.

Fixes: 99db9494035f ("IB/core: Remove ib_device.dma_device")
Signed-off-by: Bart Van Assche <bart.vanass...@wdc.com>
Cc: Leon Romanovsky <l...@kernel.org>
Signed-off-by: Jason Gunthorpe <j...@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/infiniband/core/device.c |   20 ++++++++++++++------
 drivers/infiniband/core/sysfs.c  |    1 -
 2 files changed, 14 insertions(+), 7 deletions(-)

--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -462,7 +462,6 @@ int ib_register_device(struct ib_device
        struct ib_udata uhw = {.outlen = 0, .inlen = 0};
        struct device *parent = device->dev.parent;
 
-       WARN_ON_ONCE(!parent);
        WARN_ON_ONCE(device->dma_device);
        if (device->dev.dma_ops) {
                /*
@@ -471,16 +470,25 @@ int ib_register_device(struct ib_device
                 * into device->dev.
                 */
                device->dma_device = &device->dev;
-               if (!device->dev.dma_mask)
-                       device->dev.dma_mask = parent->dma_mask;
-               if (!device->dev.coherent_dma_mask)
-                       device->dev.coherent_dma_mask =
-                               parent->coherent_dma_mask;
+               if (!device->dev.dma_mask) {
+                       if (parent)
+                               device->dev.dma_mask = parent->dma_mask;
+                       else
+                               WARN_ON_ONCE(true);
+               }
+               if (!device->dev.coherent_dma_mask) {
+                       if (parent)
+                               device->dev.coherent_dma_mask =
+                                       parent->coherent_dma_mask;
+                       else
+                               WARN_ON_ONCE(true);
+               }
        } else {
                /*
                 * The caller did not provide custom DMA operations. Use the
                 * DMA mapping operations of the parent device.
                 */
+               WARN_ON_ONCE(!parent);
                device->dma_device = parent;
        }
 
--- a/drivers/infiniband/core/sysfs.c
+++ b/drivers/infiniband/core/sysfs.c
@@ -1276,7 +1276,6 @@ int ib_device_register_sysfs(struct ib_d
        int ret;
        int i;
 
-       WARN_ON_ONCE(!device->dev.parent);
        ret = dev_set_name(class_dev, "%s", device->name);
        if (ret)
                return ret;


Reply via email to