kernel.git/drivers/s390/char, branch linux-3.7.y

s390/3215: fix tty close handling

2012-11-15T15:33:09Z

The 3215 console always has the RAW3215_FIXED flag set, which causes raw3215_shutdown() not to wait for outstanding I/O requests if an attached tty gets closed. The flag however can be simply removed, so we can guarantee that all requests belonging to the tty have been processed when the tty is closed. However the tasklet that belongs to the 3215 device may be scheduled even if there is no tty attached anymore, since we have a race between console and tty processing. Thefore unconditional tty_wakekup() in raw3215_wakeup() can cause the following NULL pointer dereference: 3.465368 Unable to handle kernel pointer dereference at virtual kernel address (null) 3.465448 Oops: 0004 #1 SMP 3.465454 Modules linked in: 3.465459 CPU: 1 Not tainted 3.6.0 #1 3.465462 Process swapper/1 (pid: 0, task: 000000003ffa4428, ksp: 000000003ffb7ce0) 3.465466 Krnl PSW : 0404100180000000 0000000000162f86 (__wake_up+0x46/0xb8) 3.465480 R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3 Krnl GPRS: fffffffffffffffe 0000000000000000 0000000000000160 0000000000000001 3.465492 0000000000000001 0000000000000004 0000000000000004 000000000096b490 3.465499 0000000000000001 0000000000000100 0000000000000001 0000000000000001 3.465506 070000003fc87d60 0000000000000160 000000003fc87d68 000000003fc87d00 3.465526 Krnl Code: 0000000000162f76: e3c0f0a80004 lg %r12,168(%r15) 0000000000162f7c: 58000370 l %r0,880 #0000000000162f80: c007ffffffff00 xilf %r0,4294967295 >0000000000162f86: ba102000 cs %r1,%r0,0(%r2) 0000000000162f8a: 1211 ltr %r1,%r1 0000000000162f8c: a774002f brc 7,162fea 0000000000162f90: b904002d lgr %r2,%r13 0000000000162f94: b904003a lgr %r3,%r10 3.465597 Call Trace: 3.465599 (<0400000000000000> 0x400000000000000) 3.465602 <000000000048c77e> raw3215_wakeup+0x2e/0x40 3.465607 <0000000000134d66> tasklet_action+0x96/0x168 3.465612 <000000000013423c> __do_softirq+0xd8/0x21c 3.465615 <0000000000134678> irq_exit+0xa8/0xac 3.465617 <000000000046c232> do_IRQ+0x182/0x248 3.465621 <00000000005c8296> io_return+0x0/0x8 3.465625 <00000000005c7cac> vtime_stop_cpu+0x4c/0xb8 3.465629 (<0000000000194e06> tick_nohz_idle_enter+0x4e/0x74) 3.465633 <0000000000104760> cpu_idle+0x170/0x184 3.465636 <00000000005b5182> smp_start_secondary+0xd6/0xe0 3.465641 <00000000005c86be> restart_int_handler+0x56/0x6c 3.465643 <0000000000000000> 0x0 3.465645 Last Breaking-Event-Address: 3.465647 <0000000000403136> tty_wakeup+0x46/0x98 3.465652 3.465654 Kernel panic - not syncing: Fatal exception in interrupt 01: HCPGIR450W CP entered; disabled wait PSW 00020001 80000000 00000000 0010F63C The easiest solution is simply to check if tty is NULL in the tasklet. If it is NULL nothing is to do (no tty attached), otherwise tty_wakeup() can be called, since we hold a reference to the tty. This is not nice... but it is a small patch and it works. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

Merge tag 'tty-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2012-10-01T19:26:52Z

Pull TTY changes from Greg Kroah-Hartman: "As we skipped the merge window for 3.6-rc1 for the tty tree, everything is now settled down and working properly, so we are ready for 3.7-rc1. Here's the patchset, it's big, but the large changes are removing a firmware file and adding a staging tty driver (it depended on the tty core changes, so it's going through this tree instead of the staging tree.) All of these patches have been in the linux-next tree for a while. Signed-off-by: Greg Kroah-Hartman " Fix up more-or-less trivial conflicts in - drivers/char/pcmcia/synclink_cs.c: tty NULL dereference fix vs tty_port_cts_enabled() helper function - drivers/staging/{Kconfig,Makefile}: add-add conflict (dgrp driver added close to other staging drivers) - drivers/staging/ipack/devices/ipoctal.c: "split ipoctal_channel from iopctal" vs "TTY: use tty_port_register_device" * tag 'tty-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (235 commits) tty/serial: Add kgdb_nmi driver tty/serial/amba-pl011: Quiesce interrupts in poll_get_char tty/serial/amba-pl011: Implement poll_init callback tty/serial/core: Introduce poll_init callback kdb: Turn KGDB_KDB=n stubs into static inlines kdb: Implement disable_nmi command kernel/debug: Mask KGDB NMI upon entry serial: pl011: handle corruption at high clock speeds serial: sccnxp: Make 'default' choice in switch last serial: sccnxp: Remove mask termios caps for SW flow control serial: sccnxp: Report actual baudrate back to core serial: samsung: Add poll_get_char & poll_put_char Powerpc 8xx CPM_UART setting MAXIDL register proportionaly to baud rate Powerpc 8xx CPM_UART maxidl should not depend on fifo size Powerpc 8xx CPM_UART too many interrupts Powerpc 8xx CPM_UART desynchronisation serial: set correct baud_base for EXSYS EX-41092 Dual 16950 serial: omap: fix the reciever line error case 8250: blacklist Winbond CIR port 8250_pnp: do pnp probe before legacy probe ...

drivers/s390/char/monreader.c: fix error return code

2012-09-26T13:45:26Z

Convert a nonnegative error return code to a negative one, as returned elsewhere in the function. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // ( if@p1 (\(ret < 0\|ret != 0\)) { ... return ret; } | ret@p1 = 0 ) ... when != ret = e1 when != &ret *if(...) { ... when != ret = e2 when forall return ret; } // Signed-off-by: Peter Senna Tschudin Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky

s390/tape: remove even more tape block leftovers

2012-09-26T13:45:20Z

Fix this compile error: In file included from drivers/s390/char/tape_core.c:29:0: drivers/s390/char/tape_std.h:103:66: warning: ‘struct request’ declared inside parameter list [enabled by default] Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/vmlogrdr: change return value from -ENOSYS to -EOPNOTSUPP

2012-09-26T13:45:16Z

Changing the return value of vmlogrdr_open() to -EOPNOTSUPP if O_NONBLOCK is specified shouldn't have any negative side effects. Any existing user wouldn't specify that flag since it wouldn't work anyway. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/sclp: use -EOPNOTSUPP instead of -ENOSYS

2012-09-26T13:45:13Z

The return value was only internally used, so it's ok to change. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/3270: drop unused spinlock from struct con3270

2012-09-26T13:45:11Z

I was checking why this spinlock was never initialized, but it turns out it's not used anywhere, so we can drop it. Signed-off-by: Jean Delvare Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

Merge 3.6-rc3 into tty-next

2012-08-27T14:13:33Z

This picks up all of the different fixes in Linus's tree that we also need here. Signed-off-by: Greg Kroah-Hartman

TTY: tty3270, add tty install

2012-08-13T23:53:14Z

This has two outcomes: * we give the TTY layer a tty_port * we do not find the info structure every time open is called on that tty In this case ->install is the only thing we want to do. We do not need ->open at all. See the tty->count > 1 check. And since we take a reference in ->install, we need also ->cleanup to drop the reference to a view. Final note, see that we leave raw3270_find_view in place. It is because views are removed even from module_exit. Signed-off-by: Jiri Slaby Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

TTY: con3215, add tty install

2012-08-13T23:50:21Z

This has two outcomes: * we give the TTY layer a tty_port * we do not find the info structure every time open is called on that tty Signed-off-by: Jiri Slaby Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman