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path: root/drivers/tty/n_gsm.c
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2016-05-21Merge tag 'tty-4.7-rc1' of ↵Linus Torvalds1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty and serial driver updates from Greg KH: "Here's the large TTY and Serial driver update for 4.7-rc1. A few new serial drivers are added here, and Peter has fixed a bunch of long-standing bugs in the tty layer and serial drivers as normal. Full details in the shortlog. All of these have been in linux-next for a while with no reported issues" * tag 'tty-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (88 commits) MAINTAINERS: 8250: remove website reference serial: core: Fix port mutex assert if lockdep disabled serial: 8250_dw: fix wrong logic in dw8250_check_lcr() tty: vt, finish looping on duplicate tty: vt, return error when con_startup fails QE-UART: add "fsl,t1040-ucc-uart" to of_device_id serial: mctrl_gpio: Drop support for out1-gpios and out2-gpios serial: 8250dw: Add device HID for future AMD UART controller Fix OpenSSH pty regression on close serial: mctrl_gpio: add IRQ locking serial: 8250: Integrate Fintek into 8250_base serial: mps2-uart: add support for early console serial: mps2-uart: add MPS2 UART driver dt-bindings: document the MPS2 UART bindings serial: sirf: Use generic uart-has-rtscts DT property serial: sirf: Introduce helper variable struct device_node *np serial: mxs-auart: Use generic uart-has-rtscts DT property serial: imx: Use generic uart-has-rtscts DT property doc: DT: Add Generic Serial Device Tree Bindings serial: 8250: of: Make tegra_serial_handle_break() static ...
2016-05-04treewide: replace dev->trans_start update with helperFlorian Westphal1-1/+1
Replace all trans_start updates with netif_trans_update helper. change was done via spatch: struct net_device *d; @@ - d->trans_start = jiffies + netif_trans_update(d) Compile tested only. Cc: user-mode-linux-devel@lists.sourceforge.net Cc: linux-xtensa@linux-xtensa.org Cc: linux1394-devel@lists.sourceforge.net Cc: linux-rdma@vger.kernel.org Cc: netdev@vger.kernel.org Cc: MPT-FusionLinux.pdl@broadcom.com Cc: linux-scsi@vger.kernel.org Cc: linux-can@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linux-omap@vger.kernel.org Cc: linux-hams@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: devel@driverdev.osuosl.org Cc: b.a.t.m.a.n@lists.open-mesh.org Cc: linux-bluetooth@vger.kernel.org Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Acked-by: Mugunthan V N <mugunthanvnm@ti.com> Acked-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-30tty: Replace ASYNC_INITIALIZED bit and update atomicallyPeter Hurley1-5/+3
Replace ASYNC_INITIALIZED bit in the tty_port::flags field with TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers tty_port_set_initialized() and tty_port_initialized() to abstract atomic bit ops. Note: the transforms for test_and_set_bit() and test_and_clear_bit() are unnecessary as the state transitions are already mutually exclusive; the tty lock prevents concurrent open/close/hangup. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-29TTY: n_gsm, fix false positive WARN_ONJiri Slaby1-1/+3
Dmitry reported, that the current cleanup code in n_gsm can trigger a warning: WARNING: CPU: 2 PID: 24238 at drivers/tty/n_gsm.c:2048 gsm_cleanup_mux+0x166/0x6b0() ... Call Trace: ... [<ffffffff81247ab9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:490 [<ffffffff828d0456>] gsm_cleanup_mux+0x166/0x6b0 drivers/tty/n_gsm.c:2048 [<ffffffff828d4d87>] gsmld_open+0x5b7/0x7a0 drivers/tty/n_gsm.c:2386 [<ffffffff828b9078>] tty_ldisc_open.isra.2+0x78/0xd0 drivers/tty/tty_ldisc.c:447 [<ffffffff828b973a>] tty_set_ldisc+0x1ca/0xa70 drivers/tty/tty_ldisc.c:567 [< inline >] tiocsetd drivers/tty/tty_io.c:2650 [<ffffffff828a14ea>] tty_ioctl+0xb2a/0x2140 drivers/tty/tty_io.c:2883 ... But this is a legal path when open fails to find a space in the gsm_mux array and tries to clean up. So make it a standard test instead of a warning. Reported-by: "Dmitry Vyukov" <dvyukov@google.com> Cc: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/r/CACT4Y+bHQbAB68VFi7Romcs-Z9ZW3kQRvcq+BvHH1oa5NcAdLA@mail.gmail.com Fixes: 5a640967 ("tty/n_gsm.c: fix a memory leak in gsmld_open()") Cc: stable <stable@vger.kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-29tty: Use termios c_*flag macrosPeter Hurley1-3/+3
Expressions of the form "tty->termios.c_*flag & FLAG" are more clearly expressed with the termios flags macros, I_FLAG(), C_FLAG(), O_FLAG(), and L_FLAG(). Convert treewide. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-28tty: Remove chars_in_buffer() line discipline methodPeter Hurley1-16/+0
The chars_in_buffer() line discipline method serves no functional purpose, other than as a (dubious) debugging aid for mostly bit-rotting drivers. Despite being documented as an optional method, every caller is unconditionally executed (although conditionally compiled). Furthermore, direct tty->ldisc access without an ldisc ref is unsafe. Lastly, N_TTY's chars_in_buffer() has warned of removal since 3.12. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-24tty: Convert use of __constant_htons to htonsVaishali Thakkar1-1/+1
In little endian cases, macro htons unfolds to __swab16 which provides special case for constants. In big endian cases, __constant_htons and htons expand directly to the same expression. So, replace __constant_htons with htons with the goal of getting rid of the definition of __constant_htons completely. The semantic patch that performs this transformation is as follows: @@expression x;@@ - __constant_htons(x) + htons(x) Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24tty: Spelling s/reseved/reserved/Geert Uytterhoeven1-1/+1
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-19Merge 4.1-rc4 into tty-nextGreg Kroah-Hartman1-3/+2
This resolves some tty driver merge issues. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10tty/n_gsm.c: fix a memory leak when gsmtty is removedPan Xinhui1-3/+2
when gsmtty_remove put dlci, it will cause memory leak if dlci->port's refcount is zero. So we do the cleanup work in .cleanup callback instead. dlci will be last put in two call chains. 1) gsmld_close -> gsm_cleanup_mux -> gsm_dlci_release -> dlci_put 2) gsmld_remove -> dlci_put so there is a race. the memory leak depends on the race. In call chain 2. we hit the memory leak. below comment tells. release_tty -> tty_driver_remove_tty -> gsmtty_remove -> dlci_put -> tty_port_destructor (WARN_ON(port->itty) and return directly) | tty->port->itty = NULL; | tty_kref_put ---> release_one_tty -> gsmtty_cleanup (added by our patch) So our patch fix the memory leak by doing the cleanup work after tty core did. Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com> Fixes: dfabf7ffa30585 Cc: stable <stable@vger.kernel.org> # 3.14+ Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-06tty: remove buf parameter from tty_name()Rasmus Villemoes1-2/+1
tty_name no longer uses the buf parameter, so remove it along with all the 64 byte stack buffers that used to be passed in. Mostly generated by the coccinelle script @depends on patch@ identifier buf; constant C; expression tty; @@ - char buf[C]; <+... - tty_name(tty, buf) + tty_name(tty) ...+> allmodconfig compiles, so I'm fairly confident the stack buffers weren't used for other purposes as well. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-10n_gsm: Drop unneeded cast on netdev_privJulia Lawall1-5/+5
The result of netdev_priv is already implicitly cast to the type of the left side of the assignment. The semantic patch that fixes this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ type T; T *x; @@ x = - (T *) netdev_priv(...) // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26tty/n_gsm: fix sparse warningLad, Prabhakar1-1/+1
this patch fixes following sparse warning: n_gsm.c:2827:22: warning: symbol 'tty_ldisc_packet' was not declared. Should it be static? Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-3/+2
Pull networking updates from David Miller: "Highlights: 1) Steady transitioning of the BPF instructure to a generic spot so all kernel subsystems can make use of it, from Alexei Starovoitov. 2) SFC driver supports busy polling, from Alexandre Rames. 3) Take advantage of hash table in UDP multicast delivery, from David Held. 4) Lighten locking, in particular by getting rid of the LRU lists, in inet frag handling. From Florian Westphal. 5) Add support for various RFC6458 control messages in SCTP, from Geir Ola Vaagland. 6) Allow to filter bridge forwarding database dumps by device, from Jamal Hadi Salim. 7) virtio-net also now supports busy polling, from Jason Wang. 8) Some low level optimization tweaks in pktgen from Jesper Dangaard Brouer. 9) Add support for ipv6 address generation modes, so that userland can have some input into the process. From Jiri Pirko. 10) Consolidate common TCP connection request code in ipv4 and ipv6, from Octavian Purdila. 11) New ARP packet logger in netfilter, from Pablo Neira Ayuso. 12) Generic resizable RCU hash table, with intial users in netlink and nftables. From Thomas Graf. 13) Maintain a name assignment type so that userspace can see where a network device name came from (enumerated by kernel, assigned explicitly by userspace, etc.) From Tom Gundersen. 14) Automatic flow label generation on transmit in ipv6, from Tom Herbert. 15) New packet timestamping facilities from Willem de Bruijn, meant to assist in measuring latencies going into/out-of the packet scheduler, latency from TCP data transmission to ACK, etc" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits) cxgb4 : Disable recursive mailbox commands when enabling vi net: reduce USB network driver config options. tg3: Modify tg3_tso_bug() to handle multiple TX rings amd-xgbe: Perform phy connect/disconnect at dev open/stop amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask net: sun4i-emac: fix memory leak on bad packet sctp: fix possible seqlock seadlock in sctp_packet_transmit() Revert "net: phy: Set the driver when registering an MDIO bus device" cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine team: Simplify return path of team_newlink bridge: Update outdated comment on promiscuous mode net-timestamp: ACK timestamp for bytestreams net-timestamp: TCP timestamping net-timestamp: SCHED timestamp on entering packet scheduler net-timestamp: add key to disambiguate concurrent datagrams net-timestamp: move timestamp flags out of sk_flags net-timestamp: extend SCM_TIMESTAMPING ancillary data struct cxgb4i : Move stray CPL definitions to cxgb4 driver tcp: reduce spurious retransmits due to transient SACK reneging qlcnic: Initialize dcbnl_ops before register_netdev ...
2014-08-02tty/n_gsm.c: fix a memory leak in gsmld_openxinhui.pan1-1/+8
If gsmld_attach_gsm fails, the gsm is not used anymore. tty core will not call gsmld_close to do the cleanup work. tty core just restore to the tty old ldisc. That always causes memory leak. Signed-off-by: xinhui.pan <xinhuiX.pan@intel.com> Reported-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-02tty: n_gsm, use setup_timerJiri Slaby1-3/+1
Just a simple cleanup of init_timer with setting the fields manually. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-24tty/n_gsm.c: get gsm->num after gsm_activate_muxxinhui.pan1-2/+2
gsm->num is the index of gsm_mux[], it's invalid before calling gsm_activate_mux. Signed-off-by: xinhui.pan <xinhuiX.pan@intel.com> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-16net: set name_assign_type in alloc_netdev()Tom Gundersen1-3/+2
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert all users to pass NET_NAME_UNKNOWN. Coccinelle patch: @@ expression sizeof_priv, name, setup, txqs, rxqs, count; @@ ( -alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs) +alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs) | -alloc_netdev_mq(sizeof_priv, name, setup, count) +alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count) | -alloc_netdev(sizeof_priv, name, setup) +alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup) ) v9: move comments here from the wrong commit Signed-off-by: Tom Gundersen <teg@jklm.no> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-07tty: n_gsm: Fix for modems with brk in modem status controlLars Poeschel1-0/+11
3GPP TS 07.10 states in section 5.4.6.3.7: "The length byte contains the value 2 or 3 ... depending on the break signal." The break byte is optional and if it is sent, the length is 3. In fact the driver was not able to work with modems that send this break byte in their modem status control message. If the modem just sends the break byte if it is really set, then weird things might happen. The code for deconding the modem status to the internal linux presentation in gsm_process_modem has already a big comment about this 2 or 3 byte length thing and it is already able to decode the brk, but the code calling the gsm_process_modem function in gsm_control_modem does not encode it and hand it over the right way. This patch fixes this. Without this fix if the modem sends the brk byte in it's modem status control message the driver will hang when opening a muxed channel. Signed-off-by: Lars Poeschel <poeschel@lemonage.de> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-19TTY/n_gsm: Removing the wrong tty_unlock/lock() in gsm_dlci_release()Chuansheng Liu1-4/+1
Commit 4d9b109060f690f5c835(tty: Prevent deadlock in n_gsm driver) tried to close all the virtual ports synchronously before closing the phycial ports, so the tty_vhangup() is used. But the tty_unlock/lock() is wrong: tty_release tty_ldisc_release tty_lock_pair(tty, o_tty) < == Here the tty is for physical port tty_ldisc_kill gsmld_close gsm_cleanup_mux gsm_dlci_release tty = tty_port_tty_get(&dlci->port) < == Here the tty(s) are for virtual port They are different ttys, so before tty_vhangup(virtual tty), do not need to call the tty_unlock(virtual tty) at all which causes unbalanced unlock warning. When enabling mutex debugging option, we will hit the below warning also: [ 99.276903] ===================================== [ 99.282172] [ BUG: bad unlock balance detected! ] [ 99.287442] 3.10.20-261976-gaec5ba0 #44 Tainted: G O [ 99.293972] ------------------------------------- [ 99.299240] mmgr/152 is trying to release lock (&tty->legacy_mutex) at: [ 99.306693] [<c1b2dcad>] mutex_unlock+0xd/0x10 [ 99.311669] but there are no more locks to release! [ 99.317131] [ 99.317131] other info that might help us debug this: [ 99.324440] 3 locks held by mmgr/152: [ 99.328542] #0: (&tty->legacy_mutex/1){......}, at: [<c1b30ab0>] tty_lock_nested+0x40/0x90 [ 99.338116] #1: (&tty->ldisc_mutex){......}, at: [<c15dbd02>] tty_ldisc_kill+0x22/0xd0 [ 99.347284] #2: (&gsm->mutex){......}, at: [<c15e3d83>] gsm_cleanup_mux+0x73/0x170 [ 99.356060] [ 99.356060] stack backtrace: [ 99.360932] CPU: 0 PID: 152 Comm: mmgr Tainted: G O 3.10.20-261976-gaec5ba0 #44 [ 99.370086] ef4a4de0 ef4a4de0 ef4c1d98 c1b27b91 ef4c1db8 c1292655 c1dd10f5 c1b2dcad [ 99.378921] c1b2dcad ef4a4de0 ef4a528c ffffffff ef4c1dfc c12930dd 00000246 00000000 [ 99.387754] 00000000 00000000 c15e1926 00000000 00000001 ddfa7530 00000003 c1b2dcad [ 99.396588] Call Trace: [ 99.399326] [<c1b27b91>] dump_stack+0x16/0x18 [ 99.404307] [<c1292655>] print_unlock_imbalance_bug+0xe5/0xf0 [ 99.410840] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.416110] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.421382] [<c12930dd>] lock_release_non_nested+0x1cd/0x210 [ 99.427818] [<c15e1926>] ? gsm_destroy_network+0x36/0x130 [ 99.433964] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.439235] [<c12931a2>] lock_release+0x82/0x1c0 [ 99.444505] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.449776] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.455047] [<c1b2dc2f>] __mutex_unlock_slowpath+0x5f/0xd0 [ 99.461288] [<c1b2dcad>] mutex_unlock+0xd/0x10 [ 99.466365] [<c1b30bb1>] tty_unlock+0x21/0x50 [ 99.471345] [<c15e3dd1>] gsm_cleanup_mux+0xc1/0x170 [ 99.476906] [<c15e44d2>] gsmld_close+0x52/0x90 [ 99.481983] [<c15db905>] tty_ldisc_close.isra.1+0x35/0x50 [ 99.488127] [<c15dbd0c>] tty_ldisc_kill+0x2c/0xd0 [ 99.493494] [<c15dc7af>] tty_ldisc_release+0x2f/0x50 [ 99.499152] [<c15d572c>] tty_release+0x37c/0x4b0 [ 99.504424] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.509695] [<c1b2dcad>] ? mutex_unlock+0xd/0x10 [ 99.514967] [<c1372f6e>] ? eventpoll_release_file+0x7e/0x90 [ 99.521307] [<c1335849>] __fput+0xd9/0x200 [ 99.525996] [<c133597d>] ____fput+0xd/0x10 [ 99.530685] [<c125c731>] task_work_run+0x81/0xb0 [ 99.535957] [<c12019e9>] do_notify_resume+0x49/0x70 [ 99.541520] [<c1b30dc4>] work_notifysig+0x29/0x31 [ 99.546897] ------------[ cut here ]------------ So here we can call tty_vhangup() directly which is for virtual port. Reviewed-by: Chao Bi <chao.bi@intel.com> Signed-off-by: Liu, Chuansheng <chuansheng.liu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17drivers: tty: Mark the functions as static in n_gsm.cRashika Kheria1-9/+5
Marks the functions gsm_cleanup_mux(), gsm_activate_mux(), gsm_free_mux(), gsm_alloc_mux() and gsm_change_mtu() as static in n_gsm.c because they are not used outside this file. Also, drop the EXPORT_SYMBOL_GPL for the above mentioned functions because nothing else in the kernel calls them. This eliminates the following warnings in n_gsm.c: drivers/tty/n_gsm.c:2022:6: warning: no previous prototype for ‘gsm_cleanup_mux’ [-Wmissing-prototypes] drivers/tty/n_gsm.c:2076:5: warning: no previous prototype for ‘gsm_activate_mux’ [-Wmissing-prototypes] drivers/tty/n_gsm.c:2120:6: warning: no previous prototype for ‘gsm_free_mux’ [-Wmissing-prototypes] drivers/tty/n_gsm.c:2156:17: warning: no previous prototype for ‘gsm_alloc_mux’ [-Wmissing-prototypes] drivers/tty/n_gsm.c:2714:5: warning: no previous prototype for ‘gsm_change_mtu’ [-Wmissing-prototypes] Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-09n_gsm: race between ld close and gsmtty openChao Bi1-10/+29
ttyA has ld associated to n_gsm, when ttyA is closing, it triggers to release gsmttyB's ld data dlci[B], then race would happen if gsmttyB is opening in parallel. (Note: This patch set differs from previous set in that it uses mutex instead of spin lock to avoid race, so that it avoids sleeping in automic context) Here are race cases we found recently in test: CASE #1 ==================================================================== releasing dlci[B] race with gsmtty_install(gsmttyB), then panic in gsmtty_open(gsmttyB), as below: tty_release(ttyA) tty_open(gsmttyB) | | ----- gsmtty_install(gsmttyB) | | ----- gsm_dlci_alloc(gsmttyB) => alloc dlci[B] tty_ldisc_release(ttyA) ----- | | gsm_dlci_release(dlci[B]) ----- | | gsm_dlci_free(dlci[B]) ----- | | ----- gsmtty_open(gsmttyB) gsmtty_open() { struct gsm_dlci *dlci = tty->driver_data; => here it uses dlci[B] ... } In gsmtty_open(gsmttyA), it uses dlci[B] which was release, so hit a panic. ===================================================================== CASE #2 ===================================================================== releasing dlci[0] race with gsmtty_install(gsmttyB), then panic in gsmtty_open(), as below: tty_release(ttyA) tty_open(gsmttyB) | | ----- gsmtty_install(gsmttyB) | | ----- gsm_dlci_alloc(gsmttyB) => alloc dlci[B] | | ----- gsmtty_open(gsmttyB) fail | | ----- tty_release(gsmttyB) | | ----- gsmtty_close(gsmttyB) | | ----- gsmtty_detach_dlci(dlci[B]) | | ----- dlci_put(dlci[B]) | | tty_ldisc_release(ttyA) ----- | | gsm_dlci_release(dlci[0]) ----- | | gsm_dlci_free(dlci[0]) ----- | | ----- dlci_put(dlci[0]) In gsmtty_detach_dlci(dlci[B]), it tries to use dlci[0] which was released, then hit panic. ===================================================================== IMHO, n_gsm tty operations would refer released ldisc, as long as gsm_dlci_release() has chance to release ldisc data when some gsmtty operations are ongoing.. This patch is try to avoid it by: 1) in n_gsm driver, use a global gsm mutex lock to avoid gsm_dlci_release() run in parallel with gsmtty_install(); 2) Increase dlci's ref count in gsmtty_install() instead of in gsmtty_open(), the purpose is to prevent gsm_dlci_release() releasing dlci after gsmtty_install() allocats dlci but before gsmtty_open increases dlci's ref count; 3) Decrease dlci's ref count in gsmtty_remove(), a tty framework API, this is the opposite process of step 2). Signed-off-by: Chao Bi <chao.bi@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-09tty: Always handle NULL flag ptrPeter Hurley1-2/+3
Most line disciplines already handle the undocumented NULL flag ptr in their .receive_buf method; however, several don't. Document the NULL flag ptr, and correct handling in the N_MOUSE, N_GSM0710 and N_R394 line disciplines. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25Drivers: tty: n_gsm.c: fixed 7 errors & 6 warnings that checkpatch complainedAldo Iljazi1-13/+16
Specifically: n_gsm.c:810: ERROR: space required before the open parenthesis '(' n_gsm.c:830: WARNING: line over 80 characters n_gsm.c:971: ERROR: trailing whitespace n_gsm.c:984: ERROR: code indent should use tabs where possible n_gsm.c:984: WARNING: please, no space before tabs n_gsm.c:984: WARNING: please, no spaces at the start of a line n_gsm.c:1141: WARNING: space prohibited before semicolon n_gsm.c:1743: ERROR: space required before the open brace '{' n_gsm.c:1744: WARNING: line over 80 characters n_gsm.c:1745: ERROR: code indent should use tabs where possible n_gsm.c:1746: ERROR: code indent should use tabs where possible n_gsm.c:2908: WARNING: line over 80 characters n_gsm.c:2912: ERROR: trailing whitespace Signed-off-by: Aldo Iljazi <neonsync1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-19TTY: fix DTR not being dropped on hang upJohan Hovold1-0/+4
Move HUPCL handling to port shutdown so that DTR is dropped also on hang up (tty_port_close is a noop for hung-up ports). Also do not try to drop DTR for uninitialised ports where it has never been raised (e.g. after a failed open). Note that this is also the current behaviour of serial-core. Nine drivers currently call tty_port_close_start directly (rather than through tty_port_close) and seven of them lower DTR as part of their close (if the port has been initialised). Fixup the remaining two drivers so that it continues to be lowered also on normal (non-HUP) close. [ Note that most of those other seven drivers did not expect DTR to have been dropped by tty_port_close_start in the first place. ] Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-19TTY: add tty_port_tty_hangup helperJiri Slaby1-5/+1
It allows for cleaning up on a considerable amount of places. They did port_get, hangup, kref_put. Now the only thing needed is to call tty_port_tty_hangup which does exactly that. And they can also decide whether to consider CLOCAL or completely ignore that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-30tty: Prevent deadlock in n_gsm driverDirkjan Bussink1-1/+41
This change fixes a deadlock when the multiplexer is closed while there are still client side ports open. When the multiplexer is closed and there are active tty's it tries to close them with tty_vhangup. This has a problem though, because tty_vhangup needs the tty_lock. This patch changes it to unlock the tty_lock before attempting the hangup and relocks afterwards. The additional call to tty_port_tty_set is needed because otherwise the port stays active because of the reference counter. This change also exposed another problem that other code paths don't expect that the multiplexer could have been closed. This patch also adds checks for these cases in the gsmtty_ class of function that could be called. The documentation explicitly states that "first close all virtual ports before closing the physical port" but we've found this to not always reality in our field situations. The GPRS / UTMS modem sometimes crashes and needs a power cycle in that case which means cleanly shutting down everything is not always possible. This change makes it much more robust for our situation where at least the system is recoverable with this patch and doesn't hang in a deadlock situation inside the kernel. The patch is against the long term support kernel (3.4.27) and should apply cleanly to more recent branches. Tested with a Telit GE864-QUADV2 and Telit HE910 modem. Signed-off-by: Dirkjan Bussink <dirkjan.bussink@nedap.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16Revert "n_gsm.c: add tx_lock in gsm_send"Greg Kroah-Hartman1-3/+0
This reverts commit f96f7f7f39af53274d98aa9c29d6fa4d122218a4, at the request of Jin. Cc: xiaojin <jin.xiao@intel.com> Cc: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16TTY: switch tty_flip_buffer_pushJiri Slaby1-31/+27
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16TTY: switch tty_insert_flip_stringJiri Slaby1-1/+1
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_string this time. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16TTY: switch tty_insert_flip_charJiri Slaby1-10/+14
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_char is the next one to proceed. This one is used all over the code, so the patch is huge. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16n_gsm.c: add tx_lock in gsm_sendxiaojin1-0/+3
All the call to gsm->output should be in the tx_lock, that could avoid potential race from MUX level. But we have no tx_lock in gsm_send. This patch is to add tx_lock in gsm_send. Signed-off-by: xiaojin <jin.xiao@intel.com> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-16TTY: n_gsm, use kref from tty_portJiri Slaby1-6/+5
After commit "TTY: move tty buffers to tty_port", the tty buffers are not freed in some drivers. This is because tty_port_destructor is not called whenever a tty_port is freed. This was an assumption I counted with but was unfortunately untrue. So fix the drivers to fulfil this assumption. Here it is enough to switch to refcounting in tty_port. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-17tty: n_gsm: Fix incorrect debug displayAlan Cox1-1/+1
In the trace we print the wrong values for N(R) on an I frame. Correct the mask. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm: memory leak in uplink error pathRuss Gorby1-2/+5
Uplink (TX) network data will go through gsm_dlci_data_output_framed there is a bug where if memory allocation fails, the skb which has already been pulled off the list will be lost. In addition TX skbs were being processed in LIFO order Fixed the memory leak, and changed to FIFO order processing Signed-off-by: Russ Gorby <russ.gorby@intel.com> Tested-by: Kappel, LaurentX <laurentx.kappel@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Showjumping <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm: replace kfree_skb w/ appropriate dev_* versionsRuss Gorby1-4/+4
Drivers are supposed to use the dev_* versions of the kfree_skb interfaces. In a couple of cases we were called with IRQs disabled as well which kfree_skb() does not expect. Replaced kfree_skb calls w/ dev_kfree_skb and dev_kfree_skb_any Signed-off-by: Russ Gorby <russ.gorby@intel.com> Tested-by: Yin, Fengwei <fengwei.yin@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Grooming <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm: avoid accessing freed memory during CMD_FCOFF conditionRuss Gorby1-27/+13
gsm_data_kick was recently modified to allow messages on the tx queue bound for DLCI0 to flow even during FCOFF conditions. Unfortunately we introduced a bug discovered by code inspection where subsequent list traversers can access freed memory if the DLCI0 messages were not all at the head of the list. Replaced singly linked tx list w/ a list_head and used provided interfaces for traversing and deleting members. Signed-off-by: Russ Gorby <russ.gorby@intel.com> Tested-by: Yin, Fengwei <fengwei.yin@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Riding School <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm: added interlocking for gsm_data_lock for certain code pathsRuss Gorby1-2/+6
There were some locking holes in the management of the MUX's message queue for 2 code paths: 1) gsmld_write_wakeup 2) receipt of CMD_FCON flow-control message In both cases gsm_data_kick is called w/o locking so it can collide with other other instances of gsm_data_kick (pulling messages tx_tail) or potentially other instances of __gsm_data_queu (adding messages to tx_head) Changed to take the tx_lock in these 2 cases Signed-off-by: Russ Gorby <russ.gorby@intel.com> Tested-by: Yin, Fengwei <fengwei.yin@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Riding School <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16char: n_gsm: remove message filtering for contipated DLCIsamix.lebsir1-24/+1
The design of uplink flow control in the mux driver is that for constipated channels data will backup into the per-channel fifos, and any messages that make it to the outbound message queue will still go out. Code was added to also stop messages that were in the outbound queue but this requires filtering through all the messages on the queue for stopped dlcis and changes some of the mux logic unneccessarily. The message fiiltering was removed to be in line w/ the original design as the message filtering does not provide any solution. Extra debug messages used during investigation were also removed. Signed-off-by: samix.lebsir <samix.lebsir@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Dressage <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm : Flow control handling in Mux driverFrederic Berat1-22/+57
- Correcting handling of FCon/FCoff in order to respect 27.010 spec - Consider FCon/off will overide all dlci flow control except for dlci0 as we must be able to send control frames. - Dlci constipated handling according to FC, RTC and RTR values. - Modifying gsm_dlci_data_kick and gsm_dlci_data_sweep according to dlci constipated value Signed-off-by: Frederic Berat <fredericx.berat@intel.com> Signed-off-by: Russ Gorby <russ.gorby@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm: uplink SKBs accumulate on listRuss Gorby1-2/+5
gsm_dlci_data_kick will not call any output function if tx_bytes > THRESH_LO furthermore it will call the output function only once if tx_bytes == 0 If the size of the IP writes are on the order of THRESH_LO we can get into a situation where skbs accumulate on the outbound list being starved for events to call the output function. gsm_dlci_data_kick now calls the sweep function when tx_bytes==0 Signed-off-by: Russ Gorby <russ.gorby@intel.com> Tested-by: Kappel, LaurentX <laurentx.kappel@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Hay and Water <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16n_gsm.c: Implement 3GPP27.010 DLC start-up procedure in MUXxiaojin1-0/+4
In 3GPP27.010 5.8.1, it defined: The TE multiplexer initiates the establishment of the multiplexer control channel by sending a SABM frame on DLCI 0 using the procedures of clause 5.4.1. Once the multiplexer channel is established other DLCs may be established using the procedures of clause 5.4.1. This patch implement 5.8.1 in MUX level, it make sure DLC0 is the first channel to be setup. [or for those not familiar with the specification: it was possible to try and open a data connection while the control channel was not yet fully open, which is a spec violation and confuses some modems] Signed-off-by: xiaojin <jin.xiao@intel.com> Tested-by: Yin, Fengwei <fengwei.yin@intel.com> [tweaked the order we check things and error code] Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: The Horsebox <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-11TTY: n_gsm, use tty_port_installJiri Slaby1-6/+24
We need to link a port to a tty in install. And since dlci is allocated even in open, we need to create gsmtty_install, allocate dlci there and create also the link. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17tty: move the termios object into the ttyAlan Cox1-4/+4
This will let us sort out a whole pile of tty related races. The alternative would be to keep points and refcount the termios objects. However 1. They are tiny anyway 2. Many devices don't use the stored copies 3. We can remove a pty special case Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08TTY: remove re-assignments to tty_driver membersJiri Slaby1-1/+0
All num, magic and owner are set by alloc_tty_driver. No need to re-set them on each allocation site. pti driver sets something different to what it passes to alloc_tty_driver. It is not a bug, since we don't use the lines parameter in any way. Anyway this is fixed, and now we do the right thing. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-11-08n_gsm: Fix timingsAlan Cox1-5/+7
Alek Du reported that the code erroneously applies time to jiffies conversions twice to the t1 and t2 values. In normal use on a modem link this cases no visible problem but on a slower link it will break as with HZ=1000 as is typical we are running t1/t2 ten times too fast. Alek's original patch removed the conversion from the timer setting but we in fact have to be more careful as the contents of t1/t2 are visible via the device API and we thus need to correct the constants. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-27tty/n_gsm: avoid fifo overflow in gsm_dlci_data_outputMikhail Kshevetskiy1-27/+31
n_gsm use a simple approach: every writing to fifo correspond exactly one reading from fifo. There are no problem in this approach until we read less bytes then we write. As result fifo may owerflow. This leads to packet loss and very slow responce. For example, this happens with ping packets (about 96 byte each) and default gsm->mtu = 64. As result we get 50 sec ping timeout and 20% packet loss. Fix the problem by reading and sending all data from the fifo Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-27tty/n_gsm: fix a bug in gsm_dlci_data_output (adaption = 2 case)Mikhail Kshevetskiy1-2/+1
in adaption=2 case we should put 1 or 2 byte with modem status bits at the beginning of a buffer pointed by "dp". n_gsm use 1 byte case, so it allocate a buffer of len + 1 size. As result we should: * put 1 byte of modem status bits * increase data pointer * put "len" bytes of data but actually we have: * increase first byte with the value of modem status bits * decrease "len" * put orig_len - 1 bytes of data starting from the buffer beggining This is evidently wrong. Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-27tty/n_gsm: fix bug in tiocmsetNikola Diklic-Perin1-1/+1
Clear bitmask was not inverted before masking modem_tx. Calling ioctl(fd, TIOCMBIC, TIOCM_RTS) results in: [ 197.430000] pre_modem_tx: 0x00000006 [ 197.430000] clear: 0x00000004 [ 197.430000] set: 0x00000000 [ 197.440000] post_modem_tx: 0x00000004 which is wrong. Signed-off-by: Nikola Diklic-Perin <diklic.perin.nikola@gmail.com> Acked-by: Alan Cox <alan@linx.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26n_gsm: Send CLD command on exitAlan Cox1-0/+8
A DISC on DLCI 0 should close down the mux but Michael Lauer reports this is not the case for some modems. Send a CLD as well. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Michael Lauer Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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