From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH for-next 5/5] IB/isert: Fix for lib/dma_debug check_sync warning Date: Wed, 16 May 2018 14:04:41 -0600 Message-ID: <20180516200441.GN25661@ziepe.ca> References: <20180516012947.12474.2286.stgit@scvm10.sc.intel.com> <20180516013137.12474.10259.stgit@scvm10.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180516013137.12474.10259.stgit@scvm10.sc.intel.com> Sender: stable-owner@vger.kernel.org To: Dennis Dalessandro Cc: dledford@redhat.com, linux-rdma@vger.kernel.org, Mike Marciniszyn , Don Dutile , Alex Estrin , stable@vger.kernel.org List-Id: linux-rdma@vger.kernel.org On Tue, May 15, 2018 at 06:31:39PM -0700, Dennis Dalessandro wrote: > From: Alex Estrin > > The following error message occurs on a target host in a debug build > during session login: > > [ 3524.411874] WARNING: CPU: 5 PID: 12063 at lib/dma-debug.c:1207 check_sync+0x4ec/0x5b0 > [ 3524.421057] infiniband hfi1_0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x0000000000000000] [size=76 bytes] > ......snip ..... > > [ 3524.535846] CPU: 5 PID: 12063 Comm: iscsi_np Kdump: loaded Not tainted 3.10.0-862.el7.x86_64.debug #1 > [ 3524.546764] Hardware name: Dell Inc. PowerEdge R430/03XKDV, BIOS 1.2.6 06/08/2015 > [ 3524.555740] Call Trace: > [ 3524.559102] [] dump_stack+0x19/0x1b > [ 3524.565477] [] __warn+0xd8/0x100 > [ 3524.571557] [] warn_slowpath_fmt+0x5f/0x80 > [ 3524.578610] [] check_sync+0x4ec/0x5b0 > [ 3524.585177] [] ? set_cpus_allowed_ptr+0x5f/0x1c0 > [ 3524.592812] [] debug_dma_sync_single_for_cpu+0x80/0x90 > [ 3524.601029] [] ? x2apic_send_IPI_mask+0x13/0x20 > [ 3524.608574] [] ? native_smp_send_reschedule+0x5b/0x80 > [ 3524.616699] [] ? resched_curr+0xf6/0x140 > [ 3524.623567] [] isert_create_send_desc.isra.26+0xe0/0x110 [ib_isert] > [ 3524.633060] [] isert_put_login_tx+0x55/0x8b0 [ib_isert] > [ 3524.641383] [] ? try_to_wake_up+0x1a4/0x430 > [ 3524.648561] [] iscsi_target_do_tx_login_io+0xdd/0x230 [iscsi_target_mod] > [ 3524.658557] [] iscsi_target_do_login+0x1a7/0x600 [iscsi_target_mod] > [ 3524.668084] [] ? kstrdup+0x49/0x60 > [ 3524.674420] [] iscsi_target_start_negotiation+0x56/0xc0 [iscsi_target_mod] > [ 3524.684656] [] __iscsi_target_login_thread+0x90e/0x1070 [iscsi_target_mod] > [ 3524.694901] [] ? __iscsi_target_login_thread+0x1070/0x1070 [iscsi_target_mod] > [ 3524.705446] [] ? __iscsi_target_login_thread+0x1070/0x1070 [iscsi_target_mod] > [ 3524.715976] [] iscsi_target_login_thread+0x28/0x60 [iscsi_target_mod] > [ 3524.725739] [] kthread+0xef/0x100 > [ 3524.732007] [] ? insert_kthread_work+0x80/0x80 > [ 3524.739540] [] ret_from_fork_nospec_begin+0x21/0x21 > [ 3524.747558] [] ? insert_kthread_work+0x80/0x80 > [ 3524.755088] ---[ end trace 23f8bf9238bd1ed8 ]--- > [ 3595.510822] iSCSI/iqn.1994-05.com.redhat:537fa56299: Unsupported SCSI Opcode 0xa3, sending CHECK_CONDITION. > > The code calls dma_sync on login_tx_desc->dma_addr prior to initializing it > with dma-mapped address. > login_tx_desc is a part of iser_conn structure and is used only once > during login negotiation, so the issue is fixed by eliminating > dma_sync call for this buffer using a special case routine. > > Cc: > Reviewed-by: Mike Marciniszyn > Reviewed-by: Don Dutile > Signed-off-by: Alex Estrin > Signed-off-by: Dennis Dalessandro > --- > drivers/infiniband/ulp/isert/ib_isert.c | 26 +++++++++++++++++--------- > 1 files changed, 17 insertions(+), 9 deletions(-) This sounds like -rc material? Why is it for-next? > diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c > index fff40b0..6a55b87 100644 > --- a/drivers/infiniband/ulp/isert/ib_isert.c > +++ b/drivers/infiniband/ulp/isert/ib_isert.c > @@ -886,15 +886,9 @@ > } > > static void > -isert_create_send_desc(struct isert_conn *isert_conn, > - struct isert_cmd *isert_cmd, > - struct iser_tx_desc *tx_desc) > +__isert_create_send_desc(struct isert_device *device, > + struct iser_tx_desc *tx_desc) > { > - struct isert_device *device = isert_conn->device; > - struct ib_device *ib_dev = device->ib_device; > - > - ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr, > - ISER_HEADERS_LEN, DMA_TO_DEVICE); > > memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl)); > tx_desc->iser_header.flags = ISCSI_CTRL; > @@ -907,6 +901,20 @@ > } > } > > +static void > +isert_create_send_desc(struct isert_conn *isert_conn, > + struct isert_cmd *isert_cmd, > + struct iser_tx_desc *tx_desc) > +{ > + struct isert_device *device = isert_conn->device; > + struct ib_device *ib_dev = device->ib_device; > + > + ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr, > + ISER_HEADERS_LEN, DMA_TO_DEVICE); > + > + __isert_create_send_desc(device, tx_desc); > +} > + > static int > isert_init_tx_hdrs(struct isert_conn *isert_conn, > struct iser_tx_desc *tx_desc) > @@ -994,7 +1002,7 @@ > struct iser_tx_desc *tx_desc = &isert_conn->login_tx_desc; > int ret; > > - isert_create_send_desc(isert_conn, NULL, tx_desc); > + __isert_create_send_desc(device, tx_desc); > > memcpy(&tx_desc->iscsi_header, &login->rsp[0], > sizeof(struct iscsi_hdr)); >