This is a note to let you know that I've just added the patch titled

IB/core: Fix two kernel warnings triggered by rxe registration

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ib-core-fix-two-kernel-warnings-triggered-by-rxe-registration.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 02ee9da347873699603d9ce0112a80b5dd69dea1 Mon Sep 17 00:00:00 2001

From: Bart Van Assche bart.vanassche@wdc.com Date: Wed, 3 Jan 2018 13:28:18 -0800 Subject: IB/core: Fix two kernel warnings triggered by rxe registration

From: Bart Van Assche bart.vanassche@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.vanassche@wdc.com Cc: Leon Romanovsky leon@kernel.org Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@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;

Patches currently in stable-queue which might be from bart.vanassche@wdc.com are

queue-4.15/ib-core-fix-two-kernel-warnings-triggered-by-rxe-registration.patch queue-4.15/rdma-rxe-fix-a-race-condition-in-rxe_requester.patch queue-4.15/rdma-rxe-fix-rxe_qp_cleanup.patch queue-4.15/rdma-rxe-fix-a-race-condition-related-to-the-qp-error-state.patch