This is a note to let you know that I've just added the patch titled RDMA/mlx5: Initialize the ODP xarray when creating an ODP MR to the 5.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: rdma-mlx5-initialize-the-odp-xarray-when-creating-an-odp-mr.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 5508546631a0f555d7088203dec2614e41b5106e Mon Sep 17 00:00:00 2001 From: Aharon Landau <aharonl@xxxxxxxxxx> Date: Tue, 19 Oct 2021 14:30:10 +0300 Subject: RDMA/mlx5: Initialize the ODP xarray when creating an ODP MR From: Aharon Landau <aharonl@xxxxxxxxxx> commit 5508546631a0f555d7088203dec2614e41b5106e upstream. Normally the zero fill would hide the missing initialization, but an errant set to desc_size in reg_create() causes a crash: BUG: unable to handle page fault for address: 0000000800000000 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 5 PID: 890 Comm: ib_write_bw Not tainted 5.15.0-rc4+ #47 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:mlx5_ib_dereg_mr+0x14/0x3b0 [mlx5_ib] Code: 48 63 cd 4c 89 f7 48 89 0c 24 e8 37 30 03 e1 48 8b 0c 24 eb a0 90 0f 1f 44 00 00 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 30 <48> 8b 2f 65 48 8b 04 25 28 00 00 00 48 89 44 24 28 31 c0 8b 87 c8 RSP: 0018:ffff88811afa3a60 EFLAGS: 00010286 RAX: 000000000000001c RBX: 0000000800000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000800000000 RBP: 0000000800000000 R08: 0000000000000000 R09: c0000000fffff7ff R10: ffff88811afa38f8 R11: ffff88811afa38f0 R12: ffffffffa02c7ac0 R13: 0000000000000000 R14: ffff88811afa3cd8 R15: ffff88810772fa00 FS: 00007f47b9080740(0000) GS:ffff88852cd40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000800000000 CR3: 000000010761e003 CR4: 0000000000370ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mlx5_ib_free_odp_mr+0x95/0xc0 [mlx5_ib] mlx5_ib_dereg_mr+0x128/0x3b0 [mlx5_ib] ib_dereg_mr_user+0x45/0xb0 [ib_core] ? xas_load+0x8/0x80 destroy_hw_idr_uobject+0x1a/0x50 [ib_uverbs] uverbs_destroy_uobject+0x2f/0x150 [ib_uverbs] uobj_destroy+0x3c/0x70 [ib_uverbs] ib_uverbs_cmd_verbs+0x467/0xb00 [ib_uverbs] ? uverbs_finalize_object+0x60/0x60 [ib_uverbs] ? ttwu_queue_wakelist+0xa9/0xe0 ? pty_write+0x85/0x90 ? file_tty_write.isra.33+0x214/0x330 ? process_echoes+0x60/0x60 ib_uverbs_ioctl+0xa7/0x110 [ib_uverbs] __x64_sys_ioctl+0x10d/0x8e0 ? vfs_write+0x17f/0x260 do_syscall_64+0x3c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Add the missing xarray initialization and remove the desc_size set. Fixes: a639e66703ee ("RDMA/mlx5: Zero out ODP related items in the mlx5_ib_mr") Link: https://lore.kernel.org/r/a4846a11c9de834663e521770da895007f9f0d30.1634642730.git.leonro@xxxxxxxxxx Signed-off-by: Aharon Landau <aharonl@xxxxxxxxxx> Reviewed-by: Maor Gottlieb <maorg@xxxxxxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/mr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1338,7 +1338,6 @@ static struct mlx5_ib_mr *reg_create(str goto err_2; } mr->mmkey.type = MLX5_MKEY_MR; - mr->desc_size = sizeof(struct mlx5_mtt); mr->umem = umem; set_mr_fields(dev, mr, umem->length, access_flags); kvfree(in); @@ -1532,6 +1531,7 @@ static struct ib_mr *create_user_odp_mr( ib_umem_release(&odp->umem); return ERR_CAST(mr); } + xa_init(&mr->implicit_children); odp->private = mr; err = mlx5r_store_odp_mkey(dev, &mr->mmkey); Patches currently in stable-queue which might be from aharonl@xxxxxxxxxx are queue-5.14/rdma-mlx5-initialize-the-odp-xarray-when-creating-an-odp-mr.patch