[PATCH for-next v2 0/3] RDMA/rtrs: bugfix and cleanups

[PATCH for-next v2 0/3] RDMA/rtrs: bugfix and cleanups

[Li Zhijian]

V2:
- Add new patch2 to fix a memory leak
- rewrite original patch2 to patch3 by refactoring the cleanup path instead of
  introducing a new flag
- Drop original patch3: RDMA/rtrs: Fix use-after-free in rtrs_clt_rdma_cm_handler
  The problem it tried to addressing doesn't appear after the new patch3
  where it adjust the cleanup order

It's trying to fix 1 issue triggered by the following script which
connect/disconnect rnbd frequently.

# cat rnbd-self.sh 
#!/bin/bash

/root/rpma/tools/config_softroce.sh eth0
modprobe rnbd_server
modprobe rnbd_client

while true;
do
        echo "sessname=xyz path=ip:<server-ip> device_path=/dev/nvme0n1" > /sys/devices/virtual/rnbd-client/ctl/map_device
        for i in /sys/block/rnbd*/rnbd/unmap_device
        do
                echo "normal" > $i
        done
done

Li Zhijian (3):
  RDMA/rtrs: remove duplicate cq_num assignment
  RDMA/rtrs: Fix the last iu->buf leak in err path
  RDMA/rtrs: Fix rxe_dealloc_pd warning

 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 56 +++++++++++---------------
 drivers/infiniband/ulp/rtrs/rtrs.c     |  4 +-
 2 files changed, 26 insertions(+), 34 deletions(-)

-- 
2.29.2

[PATCH for-next v2 1/3] RDMA/rtrs: remove duplicate cq_num assignment

[Li Zhijian]

line 1701 and 1713 are duplicate:
> 1701         cq_num = max_send_wr + max_recv_wr;
 1702         /* alloc iu to recv new rkey reply when server reports flags set */
 1703         if (clt_path->flags & RTRS_MSG_NEW_RKEY_F || con->c.cid == 0) {
 1704                 con->rsp_ius = rtrs_iu_alloc(cq_num, sizeof(*rsp),
 1705                                               GFP_KERNEL,
 1706                                               clt_path->s.dev->ib_dev,
 1707                                               DMA_FROM_DEVICE,
 1708                                               rtrs_clt_rdma_done);
 1709                 if (!con->rsp_ius)
 1710                         return -ENOMEM;
 1711                 con->queue_num = cq_num;
 1712         }
> 1713         cq_num = max_send_wr + max_recv_wr;

Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
---
V2: Add acked-by tags
---
 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index 80abf45a197a..c2065fc33a56 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -1710,7 +1710,6 @@ static int create_con_cq_qp(struct rtrs_clt_con *con)
 			return -ENOMEM;
 		con->queue_num = cq_num;
 	}
-	cq_num = max_send_wr + max_recv_wr;
 	cq_vector = con->cpu % clt_path->s.dev->ib_dev->num_comp_vectors;
 	if (con->c.cid >= clt_path->s.irq_con_num)
 		err = rtrs_cq_qp_create(&clt_path->s, &con->c, max_send_sge,
-- 
2.29.2

[PATCH for-next v2 2/3] RDMA/rtrs: Fix the last iu->buf leak in err path

[Li Zhijian]

The last iu->buf will leak if ib_dma_mapping_error() fails.

Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
---
V2: new patch to address memory leaking
---
 drivers/infiniband/ulp/rtrs/rtrs.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/ulp/rtrs/rtrs.c b/drivers/infiniband/ulp/rtrs/rtrs.c
index 4bf9d868cc52..3696f367ff51 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs.c
@@ -37,8 +37,10 @@ struct rtrs_iu *rtrs_iu_alloc(u32 iu_num, size_t size, gfp_t gfp_mask,
 			goto err;
 
 		iu->dma_addr = ib_dma_map_single(dma_dev, iu->buf, size, dir);
-		if (ib_dma_mapping_error(dma_dev, iu->dma_addr))
+		if (ib_dma_mapping_error(dma_dev, iu->dma_addr)) {
+			kfree(iu->buf);
 			goto err;
+		}
 
 		iu->cqe.done  = done;
 		iu->size      = size;
-- 
2.29.2

Re: [PATCH for-next v2 2/3] RDMA/rtrs: Fix the last iu->buf leak in err path

[Guoqing Jiang]

On 4/23/23 09:26, Li Zhijian wrote:
> The last iu->buf will leak if ib_dma_mapping_error() fails.

Fixes: c0894b3ea69d("RDMA/rtrs: core: lib functions shared between 
client and server modules")

> Signed-off-by: Li Zhijian<lizhijian@fujitsu.com>
> ---
> V2: new patch to address memory leaking
> ---
>   drivers/infiniband/ulp/rtrs/rtrs.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs.c b/drivers/infiniband/ulp/rtrs/rtrs.c
> index 4bf9d868cc52..3696f367ff51 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs.c
> @@ -37,8 +37,10 @@ struct rtrs_iu *rtrs_iu_alloc(u32 iu_num, size_t size, gfp_t gfp_mask,
>   			goto err;
>   
>   		iu->dma_addr = ib_dma_map_single(dma_dev, iu->buf, size, dir);
> -		if (ib_dma_mapping_error(dma_dev, iu->dma_addr))
> +		if (ib_dma_mapping_error(dma_dev, iu->dma_addr)) {
> +			kfree(iu->buf);
>   			goto err;
> +		}
>   
>   		iu->cqe.done  = done;
>   		iu->size      = size;

Good catch, Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>

Thanks,
Guoqing

Re: [PATCH for-next v2 2/3] RDMA/rtrs: Fix the last iu->buf leak in err path

[Jinpu Wang]

On Sun, Apr 23, 2023 at 3:27 AM Li Zhijian <lizhijian@fujitsu.com> wrote:
>
> The last iu->buf will leak if ib_dma_mapping_error() fails.
>
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Yes, as guoqing suggested, please add the Fixes tag.
Acked-by: Jack Wang <jinpu.wang@ionos.com>
> ---
> V2: new patch to address memory leaking
> ---
>  drivers/infiniband/ulp/rtrs/rtrs.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs.c b/drivers/infiniband/ulp/rtrs/rtrs.c
> index 4bf9d868cc52..3696f367ff51 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs.c
> @@ -37,8 +37,10 @@ struct rtrs_iu *rtrs_iu_alloc(u32 iu_num, size_t size, gfp_t gfp_mask,
>                         goto err;
>
>                 iu->dma_addr = ib_dma_map_single(dma_dev, iu->buf, size, dir);
> -               if (ib_dma_mapping_error(dma_dev, iu->dma_addr))
> +               if (ib_dma_mapping_error(dma_dev, iu->dma_addr)) {
> +                       kfree(iu->buf);
>                         goto err;
> +               }
>
>                 iu->cqe.done  = done;
>                 iu->size      = size;
> --
> 2.29.2
>

[PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Li Zhijian]

In current design:
1. PD and clt_path->s.dev are shared among connections.
2. every con[n]'s cleanup phase will call destroy_con_cq_qp()
3. clt_path->s.dev will be always decreased in destroy_con_cq_qp(), and
   when clt_path->s.dev become zero, it will destroy PD.
4. when con[1] failed to create, con[1] will not take clt_path->s.dev,
   but it try to decreased clt_path->s.dev

So, in case create_cm(con[0]) succeeds but create_cm(con[1])
fails, destroy_con_cq_qp(con[1]) will be called first which will destory
the PD while this PD is still taken by con[0].

Here, we refactor the error path of create_cm() and init_conns(), so that
we do the cleanup in the order they are created.

The warning occurs when destroying RXE PD whose reference count is not
zero.
-----------------------------------------------
 rnbd_client L597: Mapping device /dev/nvme0n1 on session client, (access_mode: rw, nr_poll_queues: 0)
 ------------[ cut here ]------------
 WARNING: CPU: 0 PID: 26407 at drivers/infiniband/sw/rxe/rxe_pool.c:256 __rxe_cleanup+0x13a/0x170 [rdma_rxe]
 Modules linked in: rpcrdma rdma_ucm ib_iser rnbd_client libiscsi rtrs_client scsi_transport_iscsi rtrs_core rdma_cm iw_cm ib_cm crc32_generic rdma_rxe udp_tunnel ib_uverbs ib_core kmem device_dax nd_pmem dax_pmem nd_
vme crc32c_intel fuse nvme_core nfit libnvdimm dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_mirror dm_region_hash dm_log dm_mod
 CPU: 0 PID: 26407 Comm: rnbd-client.sh Kdump: loaded Not tainted 6.2.0-rc6-roce-flush+ #53
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
 RIP: 0010:__rxe_cleanup+0x13a/0x170 [rdma_rxe]
 Code: 45 84 e4 0f 84 5a ff ff ff 48 89 ef e8 5f 18 71 f9 84 c0 75 90 be c8 00 00 00 48 89 ef e8 be 89 1f fa 85 c0 0f 85 7b ff ff ff <0f> 0b 41 bc ea ff ff ff e9 71 ff ff ff e8 84 7f 1f fa e9 d0 fe ff
 RSP: 0018:ffffb09880b6f5f0 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff99401f15d6a8 RCX: 0000000000000000
 RDX: 0000000000000001 RSI: ffffffffbac8234b RDI: 00000000ffffffff
 RBP: ffff99401f15d6d0 R08: 0000000000000001 R09: 0000000000000001
 R10: 0000000000002d82 R11: 0000000000000000 R12: 0000000000000001
 R13: ffff994101eff208 R14: ffffb09880b6f6a0 R15: 00000000fffffe00
 FS:  00007fe113904740(0000) GS:ffff99413bc00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007ff6cde656c8 CR3: 000000001f108004 CR4: 00000000001706f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  <TASK>
  rxe_dealloc_pd+0x16/0x20 [rdma_rxe]
  ib_dealloc_pd_user+0x4b/0x80 [ib_core]
  rtrs_ib_dev_put+0x79/0xd0 [rtrs_core]
  destroy_con_cq_qp+0x8a/0xa0 [rtrs_client]
  init_path+0x1e7/0x9a0 [rtrs_client]
  ? __pfx_autoremove_wake_function+0x10/0x10
  ? lock_is_held_type+0xd7/0x130
  ? rcu_read_lock_sched_held+0x43/0x80
  ? pcpu_alloc+0x3dd/0x7d0
  ? rtrs_clt_init_stats+0x18/0x40 [rtrs_client]
  rtrs_clt_open+0x24f/0x5a0 [rtrs_client]
  ? __pfx_rnbd_clt_link_ev+0x10/0x10 [rnbd_client]
  rnbd_clt_map_device+0x6a5/0xe10 [rnbd_client]

Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
---
V2: refactor error path instead of introducing a new flag #Leon
---
 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 55 +++++++++++---------------
 1 file changed, 23 insertions(+), 32 deletions(-)

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index c2065fc33a56..5234be5c6bf8 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -2039,6 +2039,7 @@ static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id,
 	return 0;
 }
 
+/* The caller should the do the cleanup in case of error */
 static int create_cm(struct rtrs_clt_con *con)
 {
 	struct rtrs_path *s = con->c.path;
@@ -2061,14 +2062,14 @@ static int create_cm(struct rtrs_clt_con *con)
 	err = rdma_set_reuseaddr(cm_id, 1);
 	if (err != 0) {
 		rtrs_err(s, "Set address reuse failed, err: %d\n", err);
-		goto destroy_cm;
+		return err;
 	}
 	err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr,
 				(struct sockaddr *)&clt_path->s.dst_addr,
 				RTRS_CONNECT_TIMEOUT_MS);
 	if (err) {
 		rtrs_err(s, "Failed to resolve address, err: %d\n", err);
-		goto destroy_cm;
+		return err;
 	}
 	/*
 	 * Combine connection status and session events. This is needed
@@ -2083,29 +2084,15 @@ static int create_cm(struct rtrs_clt_con *con)
 		if (err == 0)
 			err = -ETIMEDOUT;
 		/* Timedout or interrupted */
-		goto errr;
-	}
-	if (con->cm_err < 0) {
-		err = con->cm_err;
-		goto errr;
+		return err;
 	}
-	if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) {
+	if (con->cm_err < 0)
+		return con->cm_err;
+	if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING)
 		/* Device removal */
-		err = -ECONNABORTED;
-		goto errr;
-	}
+		return -ECONNABORTED;
 
 	return 0;
-
-errr:
-	stop_cm(con);
-	mutex_lock(&con->con_mutex);
-	destroy_con_cq_qp(con);
-	mutex_unlock(&con->con_mutex);
-destroy_cm:
-	destroy_cm(con);
-
-	return err;
 }
 
 static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path)
@@ -2333,7 +2320,7 @@ static void rtrs_clt_close_work(struct work_struct *work)
 static int init_conns(struct rtrs_clt_path *clt_path)
 {
 	unsigned int cid;
-	int err;
+	int err, i;
 
 	/*
 	 * On every new session connections increase reconnect counter
@@ -2349,10 +2336,8 @@ static int init_conns(struct rtrs_clt_path *clt_path)
 			goto destroy;
 
 		err = create_cm(to_clt_con(clt_path->s.con[cid]));
-		if (err) {
-			destroy_con(to_clt_con(clt_path->s.con[cid]));
+		if (err)
 			goto destroy;
-		}
 	}
 	err = alloc_path_reqs(clt_path);
 	if (err)
@@ -2363,15 +2348,21 @@ static int init_conns(struct rtrs_clt_path *clt_path)
 	return 0;
 
 destroy:
-	while (cid--) {
-		struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]);
+	/* Make sure we do the cleanup in the order they are created */
+	for (i = 0; i <= cid; i++) {
+		struct rtrs_clt_con *con;
 
-		stop_cm(con);
+		if (!clt_path->s.con[i])
+			break;
 
-		mutex_lock(&con->con_mutex);
-		destroy_con_cq_qp(con);
-		mutex_unlock(&con->con_mutex);
-		destroy_cm(con);
+		con = to_clt_con(clt_path->s.con[i]);
+		if (con->c.cm_id) {
+			stop_cm(con);
+			mutex_lock(&con->con_mutex);
+			destroy_con_cq_qp(con);
+			mutex_unlock(&con->con_mutex);
+			destroy_cm(con);
+		}
 		destroy_con(con);
 	}
 	/*
-- 
2.29.2

Re: [PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Guoqing Jiang]

On 4/23/23 09:26, Li Zhijian wrote:
> In current design:
> 1. PD and clt_path->s.dev are shared among connections.
> 2. every con[n]'s cleanup phase will call destroy_con_cq_qp()
> 3. clt_path->s.dev will be always decreased in destroy_con_cq_qp(), and
>     when clt_path->s.dev become zero, it will destroy PD.
> 4. when con[1] failed to create, con[1] will not take clt_path->s.dev,
>     but it try to decreased clt_path->s.dev
>
> So, in case create_cm(con[0]) succeeds but create_cm(con[1])
> fails, destroy_con_cq_qp(con[1]) will be called first which will destory
> the PD while this PD is still taken by con[0].
>
> Here, we refactor the error path of create_cm() and init_conns(), so that
> we do the cleanup in the order they are created.
>
> The warning occurs when destroying RXE PD whose reference count is not
> zero.
> -----------------------------------------------
>   rnbd_client L597: Mapping device /dev/nvme0n1 on session client, (access_mode: rw, nr_poll_queues: 0)
>   ------------[ cut here ]------------
>   WARNING: CPU: 0 PID: 26407 at drivers/infiniband/sw/rxe/rxe_pool.c:256 __rxe_cleanup+0x13a/0x170 [rdma_rxe]
>   Modules linked in: rpcrdma rdma_ucm ib_iser rnbd_client libiscsi rtrs_client scsi_transport_iscsi rtrs_core rdma_cm iw_cm ib_cm crc32_generic rdma_rxe udp_tunnel ib_uverbs ib_core kmem device_dax nd_pmem dax_pmem nd_
> vme crc32c_intel fuse nvme_core nfit libnvdimm dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_mirror dm_region_hash dm_log dm_mod
>   CPU: 0 PID: 26407 Comm: rnbd-client.sh Kdump: loaded Not tainted 6.2.0-rc6-roce-flush+ #53
>   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
>   RIP: 0010:__rxe_cleanup+0x13a/0x170 [rdma_rxe]
>   Code: 45 84 e4 0f 84 5a ff ff ff 48 89 ef e8 5f 18 71 f9 84 c0 75 90 be c8 00 00 00 48 89 ef e8 be 89 1f fa 85 c0 0f 85 7b ff ff ff <0f> 0b 41 bc ea ff ff ff e9 71 ff ff ff e8 84 7f 1f fa e9 d0 fe ff
>   RSP: 0018:ffffb09880b6f5f0 EFLAGS: 00010246
>   RAX: 0000000000000000 RBX: ffff99401f15d6a8 RCX: 0000000000000000
>   RDX: 0000000000000001 RSI: ffffffffbac8234b RDI: 00000000ffffffff
>   RBP: ffff99401f15d6d0 R08: 0000000000000001 R09: 0000000000000001
>   R10: 0000000000002d82 R11: 0000000000000000 R12: 0000000000000001
>   R13: ffff994101eff208 R14: ffffb09880b6f6a0 R15: 00000000fffffe00
>   FS:  00007fe113904740(0000) GS:ffff99413bc00000(0000) knlGS:0000000000000000
>   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>   CR2: 00007ff6cde656c8 CR3: 000000001f108004 CR4: 00000000001706f0
>   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>   Call Trace:
>    <TASK>
>    rxe_dealloc_pd+0x16/0x20 [rdma_rxe]
>    ib_dealloc_pd_user+0x4b/0x80 [ib_core]
>    rtrs_ib_dev_put+0x79/0xd0 [rtrs_core]
>    destroy_con_cq_qp+0x8a/0xa0 [rtrs_client]
>    init_path+0x1e7/0x9a0 [rtrs_client]
>    ? __pfx_autoremove_wake_function+0x10/0x10
>    ? lock_is_held_type+0xd7/0x130
>    ? rcu_read_lock_sched_held+0x43/0x80
>    ? pcpu_alloc+0x3dd/0x7d0
>    ? rtrs_clt_init_stats+0x18/0x40 [rtrs_client]
>    rtrs_clt_open+0x24f/0x5a0 [rtrs_client]
>    ? __pfx_rnbd_clt_link_ev+0x10/0x10 [rnbd_client]
>    rnbd_clt_map_device+0x6a5/0xe10 [rnbd_client]
>
> Signed-off-by: Li Zhijian<lizhijian@fujitsu.com>
> ---
> V2: refactor error path instead of introducing a new flag #Leon
> ---
>   drivers/infiniband/ulp/rtrs/rtrs-clt.c | 55 +++++++++++---------------
>   1 file changed, 23 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> index c2065fc33a56..5234be5c6bf8 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> @@ -2039,6 +2039,7 @@ static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id,
>   	return 0;
>   }
>   
> +/* The caller should the do the cleanup in case of error */

Remove the first 'the' from above sentence.

>   static int create_cm(struct rtrs_clt_con *con)
>   {
>   	struct rtrs_path *s = con->c.path;
> @@ -2061,14 +2062,14 @@ static int create_cm(struct rtrs_clt_con *con)
>   	err = rdma_set_reuseaddr(cm_id, 1);
>   	if (err != 0) {
>   		rtrs_err(s, "Set address reuse failed, err: %d\n", err);
> -		goto destroy_cm;
> +		return err;
>   	}
>   	err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr,
>   				(struct sockaddr *)&clt_path->s.dst_addr,
>   				RTRS_CONNECT_TIMEOUT_MS);
>   	if (err) {
>   		rtrs_err(s, "Failed to resolve address, err: %d\n", err);
> -		goto destroy_cm;
> +		return err;
>   	}
>   	/*
>   	 * Combine connection status and session events. This is needed
> @@ -2083,29 +2084,15 @@ static int create_cm(struct rtrs_clt_con *con)
>   		if (err == 0)
>   			err = -ETIMEDOUT;
>   		/* Timedout or interrupted */
> -		goto errr;
> -	}
> -	if (con->cm_err < 0) {
> -		err = con->cm_err;
> -		goto errr;
> +		return err;
>   	}
> -	if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) {
> +	if (con->cm_err < 0)
> +		return con->cm_err;
> +	if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING)
>   		/* Device removal */
> -		err = -ECONNABORTED;
> -		goto errr;
> -	}
> +		return -ECONNABORTED;
>   
>   	return 0;
> -
> -errr:
> -	stop_cm(con);
> -	mutex_lock(&con->con_mutex);
> -	destroy_con_cq_qp(con);
> -	mutex_unlock(&con->con_mutex);
> -destroy_cm:
> -	destroy_cm(con);
> -
> -	return err;
>   }
>   
>   static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path)
> @@ -2333,7 +2320,7 @@ static void rtrs_clt_close_work(struct work_struct *work)
>   static int init_conns(struct rtrs_clt_path *clt_path)
>   {
>   	unsigned int cid;
> -	int err;
> +	int err, i;
>   
>   	/*
>   	 * On every new session connections increase reconnect counter
> @@ -2349,10 +2336,8 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>   			goto destroy;
>   
>   		err = create_cm(to_clt_con(clt_path->s.con[cid]));
> -		if (err) {
> -			destroy_con(to_clt_con(clt_path->s.con[cid]));
> +		if (err)
>   			goto destroy;
> -		}
>   	}
>   	err = alloc_path_reqs(clt_path);
>   	if (err)
> @@ -2363,15 +2348,21 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>   	return 0;
>   
>   destroy:
> -	while (cid--) {
> -		struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]);
> +	/* Make sure we do the cleanup in the order they are created */
> +	for (i = 0; i <= cid; i++) {
> +		struct rtrs_clt_con *con;
>   
> -		stop_cm(con);
> +		if (!clt_path->s.con[i])
> +			break;
>   
> -		mutex_lock(&con->con_mutex);
> -		destroy_con_cq_qp(con);
> -		mutex_unlock(&con->con_mutex);
> -		destroy_cm(con);
> +		con = to_clt_con(clt_path->s.con[i]);
> +		if (con->c.cm_id) {
> +			stop_cm(con);
> +			mutex_lock(&con->con_mutex);
> +			destroy_con_cq_qp(con);
> +			mutex_unlock(&con->con_mutex);
> +			destroy_cm(con);
> +		}
>   		destroy_con(con);
>   	}

Can we factor out a function for above? Then rtrs_clt_stop_and_destroy_conns
might reuse it as well.

Thanks,
Guoqing

Re: [PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Zhijian Li (Fujitsu)]

On 23/04/2023 11:08, Guoqing Jiang wrote:
> 
> 
> On 4/23/23 09:26, Li Zhijian wrote:
>> In current design:
>> 1. PD and clt_path->s.dev are shared among connections.
>> 2. every con[n]'s cleanup phase will call destroy_con_cq_qp()
>> 3. clt_path->s.dev will be always decreased in destroy_con_cq_qp(), and
>>     when clt_path->s.dev become zero, it will destroy PD.
>> 4. when con[1] failed to create, con[1] will not take clt_path->s.dev,
>>     but it try to decreased clt_path->s.dev
>>
>> So, in case create_cm(con[0]) succeeds but create_cm(con[1])
>> fails, destroy_con_cq_qp(con[1]) will be called first which will destory
>> the PD while this PD is still taken by con[0].
>>
>> Here, we refactor the error path of create_cm() and init_conns(), so that
>> we do the cleanup in the order they are created.
>>
>> The warning occurs when destroying RXE PD whose reference count is not
>> zero.
>> -----------------------------------------------
>>   rnbd_client L597: Mapping device /dev/nvme0n1 on session client, (access_mode: rw, nr_poll_queues: 0)
>>   ------------[ cut here ]------------
>>   WARNING: CPU: 0 PID: 26407 at drivers/infiniband/sw/rxe/rxe_pool.c:256 __rxe_cleanup+0x13a/0x170 [rdma_rxe]
>>   Modules linked in: rpcrdma rdma_ucm ib_iser rnbd_client libiscsi rtrs_client scsi_transport_iscsi rtrs_core rdma_cm iw_cm ib_cm crc32_generic rdma_rxe udp_tunnel ib_uverbs ib_core kmem device_dax nd_pmem dax_pmem nd_
>> vme crc32c_intel fuse nvme_core nfit libnvdimm dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_mirror dm_region_hash dm_log dm_mod
>>   CPU: 0 PID: 26407 Comm: rnbd-client.sh Kdump: loaded Not tainted 6.2.0-rc6-roce-flush+ #53
>>   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
>>   RIP: 0010:__rxe_cleanup+0x13a/0x170 [rdma_rxe]
>>   Code: 45 84 e4 0f 84 5a ff ff ff 48 89 ef e8 5f 18 71 f9 84 c0 75 90 be c8 00 00 00 48 89 ef e8 be 89 1f fa 85 c0 0f 85 7b ff ff ff <0f> 0b 41 bc ea ff ff ff e9 71 ff ff ff e8 84 7f 1f fa e9 d0 fe ff
>>   RSP: 0018:ffffb09880b6f5f0 EFLAGS: 00010246
>>   RAX: 0000000000000000 RBX: ffff99401f15d6a8 RCX: 0000000000000000
>>   RDX: 0000000000000001 RSI: ffffffffbac8234b RDI: 00000000ffffffff
>>   RBP: ffff99401f15d6d0 R08: 0000000000000001 R09: 0000000000000001
>>   R10: 0000000000002d82 R11: 0000000000000000 R12: 0000000000000001
>>   R13: ffff994101eff208 R14: ffffb09880b6f6a0 R15: 00000000fffffe00
>>   FS:  00007fe113904740(0000) GS:ffff99413bc00000(0000) knlGS:0000000000000000
>>   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>   CR2: 00007ff6cde656c8 CR3: 000000001f108004 CR4: 00000000001706f0
>>   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>>   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>>   Call Trace:
>>    <TASK>
>>    rxe_dealloc_pd+0x16/0x20 [rdma_rxe]
>>    ib_dealloc_pd_user+0x4b/0x80 [ib_core]
>>    rtrs_ib_dev_put+0x79/0xd0 [rtrs_core]
>>    destroy_con_cq_qp+0x8a/0xa0 [rtrs_client]
>>    init_path+0x1e7/0x9a0 [rtrs_client]
>>    ? __pfx_autoremove_wake_function+0x10/0x10
>>    ? lock_is_held_type+0xd7/0x130
>>    ? rcu_read_lock_sched_held+0x43/0x80
>>    ? pcpu_alloc+0x3dd/0x7d0
>>    ? rtrs_clt_init_stats+0x18/0x40 [rtrs_client]
>>    rtrs_clt_open+0x24f/0x5a0 [rtrs_client]
>>    ? __pfx_rnbd_clt_link_ev+0x10/0x10 [rnbd_client]
>>    rnbd_clt_map_device+0x6a5/0xe10 [rnbd_client]
>>
>> Signed-off-by: Li Zhijian<lizhijian@fujitsu.com>
>> ---
>> V2: refactor error path instead of introducing a new flag #Leon
>> ---
>>   drivers/infiniband/ulp/rtrs/rtrs-clt.c | 55 +++++++++++---------------
>>   1 file changed, 23 insertions(+), 32 deletions(-)
>>
>> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> index c2065fc33a56..5234be5c6bf8 100644
>> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
>> @@ -2039,6 +2039,7 @@ static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id,
>>       return 0;
>>   }
>> +/* The caller should the do the cleanup in case of error */
> 
> Remove the first 'the' from above sentence.

Good catch.


> 
>>   static int create_cm(struct rtrs_clt_con *con)
>>   {
>>       struct rtrs_path *s = con->c.path;
>> @@ -2061,14 +2062,14 @@ static int create_cm(struct rtrs_clt_con *con)
>>       err = rdma_set_reuseaddr(cm_id, 1);
>>       if (err != 0) {
>>           rtrs_err(s, "Set address reuse failed, err: %d\n", err);
>> -        goto destroy_cm;
>> +        return err;
>>       }
>>       err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr,
>>                   (struct sockaddr *)&clt_path->s.dst_addr,
>>                   RTRS_CONNECT_TIMEOUT_MS);
>>       if (err) {
>>           rtrs_err(s, "Failed to resolve address, err: %d\n", err);
>> -        goto destroy_cm;
>> +        return err;
>>       }
>>       /*
>>        * Combine connection status and session events. This is needed
>> @@ -2083,29 +2084,15 @@ static int create_cm(struct rtrs_clt_con *con)
>>           if (err == 0)
>>               err = -ETIMEDOUT;
>>           /* Timedout or interrupted */
>> -        goto errr;
>> -    }
>> -    if (con->cm_err < 0) {
>> -        err = con->cm_err;
>> -        goto errr;
>> +        return err;
>>       }
>> -    if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) {
>> +    if (con->cm_err < 0)
>> +        return con->cm_err;
>> +    if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING)
>>           /* Device removal */
>> -        err = -ECONNABORTED;
>> -        goto errr;
>> -    }
>> +        return -ECONNABORTED;
>>       return 0;
>> -
>> -errr:
>> -    stop_cm(con);
>> -    mutex_lock(&con->con_mutex);
>> -    destroy_con_cq_qp(con);
>> -    mutex_unlock(&con->con_mutex);
>> -destroy_cm:
>> -    destroy_cm(con);
>> -
>> -    return err;
>>   }
>>   static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path)
>> @@ -2333,7 +2320,7 @@ static void rtrs_clt_close_work(struct work_struct *work)
>>   static int init_conns(struct rtrs_clt_path *clt_path)
>>   {
>>       unsigned int cid;
>> -    int err;
>> +    int err, i;
>>       /*
>>        * On every new session connections increase reconnect counter
>> @@ -2349,10 +2336,8 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>>               goto destroy;
>>           err = create_cm(to_clt_con(clt_path->s.con[cid]));
>> -        if (err) {
>> -            destroy_con(to_clt_con(clt_path->s.con[cid]));
>> +        if (err)
>>               goto destroy;
>> -        }
>>       }
>>       err = alloc_path_reqs(clt_path);
>>       if (err)
>> @@ -2363,15 +2348,21 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>>       return 0;
>>   destroy:
>> -    while (cid--) {
>> -        struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]);
>> +    /* Make sure we do the cleanup in the order they are created */
>> +    for (i = 0; i <= cid; i++) {
>> +        struct rtrs_clt_con *con;
>> -        stop_cm(con);
>> +        if (!clt_path->s.con[i])
>> +            break;
>> -        mutex_lock(&con->con_mutex);
>> -        destroy_con_cq_qp(con);
>> -        mutex_unlock(&con->con_mutex);
>> -        destroy_cm(con);
>> +        con = to_clt_con(clt_path->s.con[i]);
>> +        if (con->c.cm_id) {
>> +            stop_cm(con);
>> +            mutex_lock(&con->con_mutex);
>> +            destroy_con_cq_qp(con);
>> +            mutex_unlock(&con->con_mutex);
>> +            destroy_cm(con);
>> +        }
>>           destroy_con(con);
>>       }
> 
> Can we factor out a function for above? Then rtrs_clt_stop_and_destroy_conns
> might reuse it as well.

I'm open to this. but they are a bit difference IMHO.



> 
> Thanks,
> Guoqing

Re: [PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Jinpu Wang]

On Sun, Apr 23, 2023 at 9:29 AM Zhijian Li (Fujitsu)
<lizhijian@fujitsu.com> wrote:
>
>
>
> On 23/04/2023 11:08, Guoqing Jiang wrote:
> >
> >
> > On 4/23/23 09:26, Li Zhijian wrote:
> >> In current design:
> >> 1. PD and clt_path->s.dev are shared among connections.
> >> 2. every con[n]'s cleanup phase will call destroy_con_cq_qp()
> >> 3. clt_path->s.dev will be always decreased in destroy_con_cq_qp(), and
> >>     when clt_path->s.dev become zero, it will destroy PD.
> >> 4. when con[1] failed to create, con[1] will not take clt_path->s.dev,
> >>     but it try to decreased clt_path->s.dev
> >>
> >> So, in case create_cm(con[0]) succeeds but create_cm(con[1])
> >> fails, destroy_con_cq_qp(con[1]) will be called first which will destory
> >> the PD while this PD is still taken by con[0].
> >>
> >> Here, we refactor the error path of create_cm() and init_conns(), so that
> >> we do the cleanup in the order they are created.
> >>
> >> The warning occurs when destroying RXE PD whose reference count is not
> >> zero.
> >> -----------------------------------------------
> >>   rnbd_client L597: Mapping device /dev/nvme0n1 on session client, (access_mode: rw, nr_poll_queues: 0)
> >>   ------------[ cut here ]------------
> >>   WARNING: CPU: 0 PID: 26407 at drivers/infiniband/sw/rxe/rxe_pool.c:256 __rxe_cleanup+0x13a/0x170 [rdma_rxe]
> >>   Modules linked in: rpcrdma rdma_ucm ib_iser rnbd_client libiscsi rtrs_client scsi_transport_iscsi rtrs_core rdma_cm iw_cm ib_cm crc32_generic rdma_rxe udp_tunnel ib_uverbs ib_core kmem device_dax nd_pmem dax_pmem nd_
> >> vme crc32c_intel fuse nvme_core nfit libnvdimm dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_mirror dm_region_hash dm_log dm_mod
> >>   CPU: 0 PID: 26407 Comm: rnbd-client.sh Kdump: loaded Not tainted 6.2.0-rc6-roce-flush+ #53
> >>   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
> >>   RIP: 0010:__rxe_cleanup+0x13a/0x170 [rdma_rxe]
> >>   Code: 45 84 e4 0f 84 5a ff ff ff 48 89 ef e8 5f 18 71 f9 84 c0 75 90 be c8 00 00 00 48 89 ef e8 be 89 1f fa 85 c0 0f 85 7b ff ff ff <0f> 0b 41 bc ea ff ff ff e9 71 ff ff ff e8 84 7f 1f fa e9 d0 fe ff
> >>   RSP: 0018:ffffb09880b6f5f0 EFLAGS: 00010246
> >>   RAX: 0000000000000000 RBX: ffff99401f15d6a8 RCX: 0000000000000000
> >>   RDX: 0000000000000001 RSI: ffffffffbac8234b RDI: 00000000ffffffff
> >>   RBP: ffff99401f15d6d0 R08: 0000000000000001 R09: 0000000000000001
> >>   R10: 0000000000002d82 R11: 0000000000000000 R12: 0000000000000001
> >>   R13: ffff994101eff208 R14: ffffb09880b6f6a0 R15: 00000000fffffe00
> >>   FS:  00007fe113904740(0000) GS:ffff99413bc00000(0000) knlGS:0000000000000000
> >>   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> >>   CR2: 00007ff6cde656c8 CR3: 000000001f108004 CR4: 00000000001706f0
> >>   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> >>   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> >>   Call Trace:
> >>    <TASK>
> >>    rxe_dealloc_pd+0x16/0x20 [rdma_rxe]
> >>    ib_dealloc_pd_user+0x4b/0x80 [ib_core]
> >>    rtrs_ib_dev_put+0x79/0xd0 [rtrs_core]
> >>    destroy_con_cq_qp+0x8a/0xa0 [rtrs_client]
> >>    init_path+0x1e7/0x9a0 [rtrs_client]
> >>    ? __pfx_autoremove_wake_function+0x10/0x10
> >>    ? lock_is_held_type+0xd7/0x130
> >>    ? rcu_read_lock_sched_held+0x43/0x80
> >>    ? pcpu_alloc+0x3dd/0x7d0
> >>    ? rtrs_clt_init_stats+0x18/0x40 [rtrs_client]
> >>    rtrs_clt_open+0x24f/0x5a0 [rtrs_client]
> >>    ? __pfx_rnbd_clt_link_ev+0x10/0x10 [rnbd_client]
> >>    rnbd_clt_map_device+0x6a5/0xe10 [rnbd_client]
> >>
> >> Signed-off-by: Li Zhijian<lizhijian@fujitsu.com>
> >> ---
> >> V2: refactor error path instead of introducing a new flag #Leon
> >> ---
> >>   drivers/infiniband/ulp/rtrs/rtrs-clt.c | 55 +++++++++++---------------
> >>   1 file changed, 23 insertions(+), 32 deletions(-)
> >>
> >> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> >> index c2065fc33a56..5234be5c6bf8 100644
> >> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> >> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> >> @@ -2039,6 +2039,7 @@ static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id,
> >>       return 0;
> >>   }
> >> +/* The caller should the do the cleanup in case of error */
> >
> > Remove the first 'the' from above sentence.
>
> Good catch.
>
>
> >
> >>   static int create_cm(struct rtrs_clt_con *con)
> >>   {
> >>       struct rtrs_path *s = con->c.path;
> >> @@ -2061,14 +2062,14 @@ static int create_cm(struct rtrs_clt_con *con)
> >>       err = rdma_set_reuseaddr(cm_id, 1);
> >>       if (err != 0) {
> >>           rtrs_err(s, "Set address reuse failed, err: %d\n", err);
> >> -        goto destroy_cm;
> >> +        return err;
> >>       }
> >>       err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr,
> >>                   (struct sockaddr *)&clt_path->s.dst_addr,
> >>                   RTRS_CONNECT_TIMEOUT_MS);
> >>       if (err) {
> >>           rtrs_err(s, "Failed to resolve address, err: %d\n", err);
> >> -        goto destroy_cm;
> >> +        return err;
> >>       }
> >>       /*
> >>        * Combine connection status and session events. This is needed
> >> @@ -2083,29 +2084,15 @@ static int create_cm(struct rtrs_clt_con *con)
> >>           if (err == 0)
> >>               err = -ETIMEDOUT;
> >>           /* Timedout or interrupted */
> >> -        goto errr;
> >> -    }
> >> -    if (con->cm_err < 0) {
> >> -        err = con->cm_err;
> >> -        goto errr;
> >> +        return err;
> >>       }
> >> -    if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) {
> >> +    if (con->cm_err < 0)
> >> +        return con->cm_err;
> >> +    if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING)
> >>           /* Device removal */
> >> -        err = -ECONNABORTED;
> >> -        goto errr;
> >> -    }
> >> +        return -ECONNABORTED;
> >>       return 0;
> >> -
> >> -errr:
> >> -    stop_cm(con);
> >> -    mutex_lock(&con->con_mutex);
> >> -    destroy_con_cq_qp(con);
> >> -    mutex_unlock(&con->con_mutex);
> >> -destroy_cm:
> >> -    destroy_cm(con);
> >> -
> >> -    return err;
> >>   }
> >>   static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path)
> >> @@ -2333,7 +2320,7 @@ static void rtrs_clt_close_work(struct work_struct *work)
> >>   static int init_conns(struct rtrs_clt_path *clt_path)
> >>   {
> >>       unsigned int cid;
> >> -    int err;
> >> +    int err, i;
> >>       /*
> >>        * On every new session connections increase reconnect counter
> >> @@ -2349,10 +2336,8 @@ static int init_conns(struct rtrs_clt_path *clt_path)
> >>               goto destroy;
> >>           err = create_cm(to_clt_con(clt_path->s.con[cid]));
> >> -        if (err) {
> >> -            destroy_con(to_clt_con(clt_path->s.con[cid]));
> >> +        if (err)
> >>               goto destroy;
> >> -        }
> >>       }
> >>       err = alloc_path_reqs(clt_path);
> >>       if (err)
> >> @@ -2363,15 +2348,21 @@ static int init_conns(struct rtrs_clt_path *clt_path)
> >>       return 0;
> >>   destroy:
> >> -    while (cid--) {
> >> -        struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]);
> >> +    /* Make sure we do the cleanup in the order they are created */
> >> +    for (i = 0; i <= cid; i++) {
> >> +        struct rtrs_clt_con *con;
> >> -        stop_cm(con);
> >> +        if (!clt_path->s.con[i])
> >> +            break;
> >> -        mutex_lock(&con->con_mutex);
> >> -        destroy_con_cq_qp(con);
> >> -        mutex_unlock(&con->con_mutex);
> >> -        destroy_cm(con);
> >> +        con = to_clt_con(clt_path->s.con[i]);
> >> +        if (con->c.cm_id) {
> >> +            stop_cm(con);
> >> +            mutex_lock(&con->con_mutex);
> >> +            destroy_con_cq_qp(con);
> >> +            mutex_unlock(&con->con_mutex);
> >> +            destroy_cm(con);
> >> +        }
> >>           destroy_con(con);
> >>       }
> >
> > Can we factor out a function for above? Then rtrs_clt_stop_and_destroy_conns
> > might reuse it as well.
>
> I'm open to this. but they are a bit difference IMHO.
we can do the refactor later after bugfix.

Thx
>
>
>
> >
> > Thanks,
> > Guoqing

Re: [PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Guoqing Jiang]

On 4/24/23 12:33, Jinpu Wang wrote:
>>> Can we factor out a function for above? Then rtrs_clt_stop_and_destroy_conns
>>> might reuse it as well.
>> I'm open to this. but they are a bit difference IMHO.
> we can do the refactor later after bugfix.

Yes, maybe next cycle.

Thanks,
Guoqing

Re: [PATCH for-next v2 3/3] RDMA/rtrs: Fix rxe_dealloc_pd warning

[Jinpu Wang]

On Sun, Apr 23, 2023 at 3:27 AM Li Zhijian <lizhijian@fujitsu.com> wrote:
>
> In current design:
> 1. PD and clt_path->s.dev are shared among connections.
> 2. every con[n]'s cleanup phase will call destroy_con_cq_qp()
> 3. clt_path->s.dev will be always decreased in destroy_con_cq_qp(), and
>    when clt_path->s.dev become zero, it will destroy PD.
> 4. when con[1] failed to create, con[1] will not take clt_path->s.dev,
>    but it try to decreased clt_path->s.dev
>
> So, in case create_cm(con[0]) succeeds but create_cm(con[1])
> fails, destroy_con_cq_qp(con[1]) will be called first which will destory
> the PD while this PD is still taken by con[0].
>
> Here, we refactor the error path of create_cm() and init_conns(), so that
> we do the cleanup in the order they are created.
>
> The warning occurs when destroying RXE PD whose reference count is not
> zero.
> -----------------------------------------------
>  rnbd_client L597: Mapping device /dev/nvme0n1 on session client, (access_mode: rw, nr_poll_queues: 0)
>  ------------[ cut here ]------------
>  WARNING: CPU: 0 PID: 26407 at drivers/infiniband/sw/rxe/rxe_pool.c:256 __rxe_cleanup+0x13a/0x170 [rdma_rxe]
>  Modules linked in: rpcrdma rdma_ucm ib_iser rnbd_client libiscsi rtrs_client scsi_transport_iscsi rtrs_core rdma_cm iw_cm ib_cm crc32_generic rdma_rxe udp_tunnel ib_uverbs ib_core kmem device_dax nd_pmem dax_pmem nd_
> vme crc32c_intel fuse nvme_core nfit libnvdimm dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua dm_mirror dm_region_hash dm_log dm_mod
>  CPU: 0 PID: 26407 Comm: rnbd-client.sh Kdump: loaded Not tainted 6.2.0-rc6-roce-flush+ #53
>  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
>  RIP: 0010:__rxe_cleanup+0x13a/0x170 [rdma_rxe]
>  Code: 45 84 e4 0f 84 5a ff ff ff 48 89 ef e8 5f 18 71 f9 84 c0 75 90 be c8 00 00 00 48 89 ef e8 be 89 1f fa 85 c0 0f 85 7b ff ff ff <0f> 0b 41 bc ea ff ff ff e9 71 ff ff ff e8 84 7f 1f fa e9 d0 fe ff
>  RSP: 0018:ffffb09880b6f5f0 EFLAGS: 00010246
>  RAX: 0000000000000000 RBX: ffff99401f15d6a8 RCX: 0000000000000000
>  RDX: 0000000000000001 RSI: ffffffffbac8234b RDI: 00000000ffffffff
>  RBP: ffff99401f15d6d0 R08: 0000000000000001 R09: 0000000000000001
>  R10: 0000000000002d82 R11: 0000000000000000 R12: 0000000000000001
>  R13: ffff994101eff208 R14: ffffb09880b6f6a0 R15: 00000000fffffe00
>  FS:  00007fe113904740(0000) GS:ffff99413bc00000(0000) knlGS:0000000000000000
>  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>  CR2: 00007ff6cde656c8 CR3: 000000001f108004 CR4: 00000000001706f0
>  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>  Call Trace:
>   <TASK>
>   rxe_dealloc_pd+0x16/0x20 [rdma_rxe]
>   ib_dealloc_pd_user+0x4b/0x80 [ib_core]
>   rtrs_ib_dev_put+0x79/0xd0 [rtrs_core]
>   destroy_con_cq_qp+0x8a/0xa0 [rtrs_client]
>   init_path+0x1e7/0x9a0 [rtrs_client]
>   ? __pfx_autoremove_wake_function+0x10/0x10
>   ? lock_is_held_type+0xd7/0x130
>   ? rcu_read_lock_sched_held+0x43/0x80
>   ? pcpu_alloc+0x3dd/0x7d0
>   ? rtrs_clt_init_stats+0x18/0x40 [rtrs_client]
>   rtrs_clt_open+0x24f/0x5a0 [rtrs_client]
>   ? __pfx_rnbd_clt_link_ev+0x10/0x10 [rnbd_client]
>   rnbd_clt_map_device+0x6a5/0xe10 [rnbd_client]
>
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
I've tested this version, and it works fine and looks fine.
Ack-by: Jack Wang <jinpu.wang@ionos.com>
Tested-by: Jack Wang <jinpu.wang@ionos.com>

Thx!
> ---
> V2: refactor error path instead of introducing a new flag #Leon
> ---
>  drivers/infiniband/ulp/rtrs/rtrs-clt.c | 55 +++++++++++---------------
>  1 file changed, 23 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> index c2065fc33a56..5234be5c6bf8 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
> @@ -2039,6 +2039,7 @@ static int rtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id,
>         return 0;
>  }
>
> +/* The caller should the do the cleanup in case of error */
>  static int create_cm(struct rtrs_clt_con *con)
>  {
>         struct rtrs_path *s = con->c.path;
> @@ -2061,14 +2062,14 @@ static int create_cm(struct rtrs_clt_con *con)
>         err = rdma_set_reuseaddr(cm_id, 1);
>         if (err != 0) {
>                 rtrs_err(s, "Set address reuse failed, err: %d\n", err);
> -               goto destroy_cm;
> +               return err;
>         }
>         err = rdma_resolve_addr(cm_id, (struct sockaddr *)&clt_path->s.src_addr,
>                                 (struct sockaddr *)&clt_path->s.dst_addr,
>                                 RTRS_CONNECT_TIMEOUT_MS);
>         if (err) {
>                 rtrs_err(s, "Failed to resolve address, err: %d\n", err);
> -               goto destroy_cm;
> +               return err;
>         }
>         /*
>          * Combine connection status and session events. This is needed
> @@ -2083,29 +2084,15 @@ static int create_cm(struct rtrs_clt_con *con)
>                 if (err == 0)
>                         err = -ETIMEDOUT;
>                 /* Timedout or interrupted */
> -               goto errr;
> -       }
> -       if (con->cm_err < 0) {
> -               err = con->cm_err;
> -               goto errr;
> +               return err;
>         }
> -       if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING) {
> +       if (con->cm_err < 0)
> +               return con->cm_err;
> +       if (READ_ONCE(clt_path->state) != RTRS_CLT_CONNECTING)
>                 /* Device removal */
> -               err = -ECONNABORTED;
> -               goto errr;
> -       }
> +               return -ECONNABORTED;
>
>         return 0;
> -
> -errr:
> -       stop_cm(con);
> -       mutex_lock(&con->con_mutex);
> -       destroy_con_cq_qp(con);
> -       mutex_unlock(&con->con_mutex);
> -destroy_cm:
> -       destroy_cm(con);
> -
> -       return err;
>  }
>
>  static void rtrs_clt_path_up(struct rtrs_clt_path *clt_path)
> @@ -2333,7 +2320,7 @@ static void rtrs_clt_close_work(struct work_struct *work)
>  static int init_conns(struct rtrs_clt_path *clt_path)
>  {
>         unsigned int cid;
> -       int err;
> +       int err, i;
>
>         /*
>          * On every new session connections increase reconnect counter
> @@ -2349,10 +2336,8 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>                         goto destroy;
>
>                 err = create_cm(to_clt_con(clt_path->s.con[cid]));
> -               if (err) {
> -                       destroy_con(to_clt_con(clt_path->s.con[cid]));
> +               if (err)
>                         goto destroy;
> -               }
>         }
>         err = alloc_path_reqs(clt_path);
>         if (err)
> @@ -2363,15 +2348,21 @@ static int init_conns(struct rtrs_clt_path *clt_path)
>         return 0;
>
>  destroy:
> -       while (cid--) {
> -               struct rtrs_clt_con *con = to_clt_con(clt_path->s.con[cid]);
> +       /* Make sure we do the cleanup in the order they are created */
> +       for (i = 0; i <= cid; i++) {
> +               struct rtrs_clt_con *con;
>
> -               stop_cm(con);
> +               if (!clt_path->s.con[i])
> +                       break;
>
> -               mutex_lock(&con->con_mutex);
> -               destroy_con_cq_qp(con);
> -               mutex_unlock(&con->con_mutex);
> -               destroy_cm(con);
> +               con = to_clt_con(clt_path->s.con[i]);
> +               if (con->c.cm_id) {
> +                       stop_cm(con);
> +                       mutex_lock(&con->con_mutex);
> +                       destroy_con_cq_qp(con);
> +                       mutex_unlock(&con->con_mutex);
> +                       destroy_cm(con);
> +               }
>                 destroy_con(con);
>         }
>         /*
> --
> 2.29.2
>

Re: [PATCH for-next v2 0/3] RDMA/rtrs: bugfix and cleanups

[Zhijian Li (Fujitsu)]

Jack, Guoqing


Thank you all for the reviewing and testing, I will post a new version soon.



On 23/04/2023 09:26, Li Zhijian wrote:
> V2:
> - Add new patch2 to fix a memory leak
> - rewrite original patch2 to patch3 by refactoring the cleanup path instead of
>    introducing a new flag
> - Drop original patch3: RDMA/rtrs: Fix use-after-free in rtrs_clt_rdma_cm_handler
>    The problem it tried to addressing doesn't appear after the new patch3Jack
>    where it adjust the cleanup order
> 
> It's trying to fix 1 issue triggered by the following script which
> connect/disconnect rnbd frequently.
> 
> # cat rnbd-self.sh
> #!/bin/bash
> 
> /root/rpma/tools/config_softroce.sh eth0
> modprobe rnbd_server
> modprobe rnbd_client
> 
> while true;
> do
>          echo "sessname=xyz path=ip:<server-ip> device_path=/dev/nvme0n1" > /sys/devices/virtual/rnbd-client/ctl/map_device
>          for i in /sys/block/rnbd*/rnbd/unmap_device
>          do
>                  echo "normal" > $i
>          done
> done
> 
> Li Zhijian (3):
>    RDMA/rtrs: remove duplicate cq_num assignment
>    RDMA/rtrs: Fix the last iu->buf leak in err path
>    RDMA/rtrs: Fix rxe_dealloc_pd warning
> 
>   drivers/infiniband/ulp/rtrs/rtrs-clt.c | 56 +++++++++++---------------
>   drivers/infiniband/ulp/rtrs/rtrs.c     |  4 +-
>   2 files changed, 26 insertions(+), 34 deletions(-)
>