| Message ID | 1697009600-22367-4-git-send-email-alibuda@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | net/smc: bugfixs for smc-r | expand |
On 11.10.23 09:33, D. Wythe wrote: > From: "D. Wythe" <alibuda@linux.alibaba.com> > > This patch re-fix the issues memtianed by commit 22a825c541d7 > ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()"). > > Blocking sending message do solve the issues though, but it also > prevents the peer to receive the final message. Besides, in logic, > whether the sndbuf_desc is NULL or not have no impact on the processing > of cdc message sending. > Agree. > Hence that, this patch allow the cdc message sending but to check the > sndbuf_desc with care in smc_cdc_tx_handler(). > > Fixes: 22a825c541d7 ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()") > Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> > --- > net/smc/smc_cdc.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c > index 01bdb79..3c06625 100644 > --- a/net/smc/smc_cdc.c > +++ b/net/smc/smc_cdc.c > @@ -28,13 +28,15 @@ static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd, > { > struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd; > struct smc_connection *conn = cdcpend->conn; > + struct smc_buf_desc *sndbuf_desc; > struct smc_sock *smc; > int diff; > > + sndbuf_desc = conn->sndbuf_desc; > smc = container_of(conn, struct smc_sock, conn); > bh_lock_sock(&smc->sk); > - if (!wc_status) { > - diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len, > + if (!wc_status && sndbuf_desc) { > + diff = smc_curs_diff(sndbuf_desc->len, How could this guarantee that the sndbuf_desc would not be NULL? > &cdcpend->conn->tx_curs_fin, > &cdcpend->cursor); > /* sndbuf_space is decreased in smc_sendmsg */ > @@ -114,9 +116,6 @@ int smc_cdc_msg_send(struct smc_connection *conn, > union smc_host_cursor cfed; > int rc; > > - if (unlikely(!READ_ONCE(conn->sndbuf_desc))) > - return -ENOBUFS; > - > smc_cdc_add_pending_send(conn, pend); > > conn->tx_cdc_seq++;
On 10/12/23 4:37 AM, Wenjia Zhang wrote: > > > On 11.10.23 09:33, D. Wythe wrote: >> From: "D. Wythe" <alibuda@linux.alibaba.com> >> >> This patch re-fix the issues memtianed by commit 22a825c541d7 >> ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()"). >> >> Blocking sending message do solve the issues though, but it also >> prevents the peer to receive the final message. Besides, in logic, >> whether the sndbuf_desc is NULL or not have no impact on the processing >> of cdc message sending. >> > Agree. > >> Hence that, this patch allow the cdc message sending but to check the >> sndbuf_desc with care in smc_cdc_tx_handler(). >> >> Fixes: 22a825c541d7 ("net/smc: fix NULL sndbuf_desc in >> smc_cdc_tx_handler()") >> Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> >> --- >> net/smc/smc_cdc.c | 9 ++++----- >> 1 file changed, 4 insertions(+), 5 deletions(-) >> >> diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c >> index 01bdb79..3c06625 100644 >> --- a/net/smc/smc_cdc.c >> +++ b/net/smc/smc_cdc.c >> @@ -28,13 +28,15 @@ static void smc_cdc_tx_handler(struct >> smc_wr_tx_pend_priv *pnd_snd, >> { >> struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend >> *)pnd_snd; >> struct smc_connection *conn = cdcpend->conn; >> + struct smc_buf_desc *sndbuf_desc; >> struct smc_sock *smc; >> int diff; >> + sndbuf_desc = conn->sndbuf_desc; >> smc = container_of(conn, struct smc_sock, conn); >> bh_lock_sock(&smc->sk); >> - if (!wc_status) { >> - diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len, >> + if (!wc_status && sndbuf_desc) { >> + diff = smc_curs_diff(sndbuf_desc->len, > How could this guarantee that the sndbuf_desc would not be NULL? > It can not guarantee he sndbuf_desc would not be NULL, but it will prevents the smc_cdc_tx_handler() to access a NULL sndbuf_desc. So that we can avoid the panic descried in commit 22a825c541d7 ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()"). >> &cdcpend->conn->tx_curs_fin, >> &cdcpend->cursor); >> /* sndbuf_space is decreased in smc_sendmsg */ >> @@ -114,9 +116,6 @@ int smc_cdc_msg_send(struct smc_connection *conn, >> union smc_host_cursor cfed; >> int rc; >> - if (unlikely(!READ_ONCE(conn->sndbuf_desc))) >> - return -ENOBUFS; >> - >> smc_cdc_add_pending_send(conn, pend); >> conn->tx_cdc_seq++;
On 12.10.23 04:49, D. Wythe wrote: > > > On 10/12/23 4:37 AM, Wenjia Zhang wrote: >> >> >> On 11.10.23 09:33, D. Wythe wrote: >>> From: "D. Wythe" <alibuda@linux.alibaba.com> >>> >>> This patch re-fix the issues memtianed by commit 22a825c541d7 >>> ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()"). >>> >>> Blocking sending message do solve the issues though, but it also >>> prevents the peer to receive the final message. Besides, in logic, >>> whether the sndbuf_desc is NULL or not have no impact on the processing >>> of cdc message sending. >>> >> Agree. >> >>> Hence that, this patch allow the cdc message sending but to check the >>> sndbuf_desc with care in smc_cdc_tx_handler(). >>> >>> Fixes: 22a825c541d7 ("net/smc: fix NULL sndbuf_desc in >>> smc_cdc_tx_handler()") >>> Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> >>> --- >>> net/smc/smc_cdc.c | 9 ++++----- >>> 1 file changed, 4 insertions(+), 5 deletions(-) >>> >>> diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c >>> index 01bdb79..3c06625 100644 >>> --- a/net/smc/smc_cdc.c >>> +++ b/net/smc/smc_cdc.c >>> @@ -28,13 +28,15 @@ static void smc_cdc_tx_handler(struct >>> smc_wr_tx_pend_priv *pnd_snd, >>> { >>> struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend >>> *)pnd_snd; >>> struct smc_connection *conn = cdcpend->conn; >>> + struct smc_buf_desc *sndbuf_desc; >>> struct smc_sock *smc; >>> int diff; >>> + sndbuf_desc = conn->sndbuf_desc; >>> smc = container_of(conn, struct smc_sock, conn); >>> bh_lock_sock(&smc->sk); >>> - if (!wc_status) { >>> - diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len, >>> + if (!wc_status && sndbuf_desc) { >>> + diff = smc_curs_diff(sndbuf_desc->len, >> How could this guarantee that the sndbuf_desc would not be NULL? >> > > It can not guarantee he sndbuf_desc would not be NULL, but it will prevents > the smc_cdc_tx_handler() to access a NULL sndbuf_desc. So that we > can avoid the panic descried in commit 22a825c541d7 > ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()"). > got it, thanks! Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com> >>> &cdcpend->conn->tx_curs_fin, >>> &cdcpend->cursor); >>> /* sndbuf_space is decreased in smc_sendmsg */ >>> @@ -114,9 +116,6 @@ int smc_cdc_msg_send(struct smc_connection *conn, >>> union smc_host_cursor cfed; >>> int rc; >>> - if (unlikely(!READ_ONCE(conn->sndbuf_desc))) >>> - return -ENOBUFS; >>> - >>> smc_cdc_add_pending_send(conn, pend); >>> conn->tx_cdc_seq++; >
diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c index 01bdb79..3c06625 100644 --- a/net/smc/smc_cdc.c +++ b/net/smc/smc_cdc.c @@ -28,13 +28,15 @@ static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd, { struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd; struct smc_connection *conn = cdcpend->conn; + struct smc_buf_desc *sndbuf_desc; struct smc_sock *smc; int diff; + sndbuf_desc = conn->sndbuf_desc; smc = container_of(conn, struct smc_sock, conn); bh_lock_sock(&smc->sk); - if (!wc_status) { - diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len, + if (!wc_status && sndbuf_desc) { + diff = smc_curs_diff(sndbuf_desc->len, &cdcpend->conn->tx_curs_fin, &cdcpend->cursor); /* sndbuf_space is decreased in smc_sendmsg */ @@ -114,9 +116,6 @@ int smc_cdc_msg_send(struct smc_connection *conn, union smc_host_cursor cfed; int rc; - if (unlikely(!READ_ONCE(conn->sndbuf_desc))) - return -ENOBUFS; - smc_cdc_add_pending_send(conn, pend); conn->tx_cdc_seq++;