nixiaoming c79dde629d tty fix oops when rmmod 8250 ...

After rmmod 8250.ko
tty_kref_put starts kwork (release_one_tty) to release proc interface
oops when accessing driver->driver_name in proc_tty_unregister_driver

Use jprobe, found driver->driver_name point to 8250.ko
static static struct uart_driver serial8250_reg
.driver_name= serial,

Use name in proc_dir_entry instead of driver->driver_name to fix oops

test on linux 4.1.12:

BUG: unable to handle kernel paging request at ffffffffa01979de
IP: [<ffffffff81310f40>] strchr+0x0/0x30
PGD 1a0d067 PUD 1a0e063 PMD 851c1f067 PTE 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: ... ...  [last unloaded: 8250]
CPU: 7 PID: 116 Comm: kworker/7:1 Tainted: G           O    4.1.12 #1
Hardware name: Insyde RiverForest/Type2 - Board Product Name1, BIOS NE5KV904 12/21/2015
Workqueue: events release_one_tty
task: ffff88085b684960 ti: ffff880852884000 task.ti: ffff880852884000
RIP: 0010:[<ffffffff81310f40>]  [<ffffffff81310f40>] strchr+0x0/0x30
RSP: 0018:ffff880852887c90  EFLAGS: 00010282
RAX: ffffffff81a5eca0 RBX: ffffffffa01979de RCX: 0000000000000004
RDX: ffff880852887d10 RSI: 000000000000002f RDI: ffffffffa01979de
RBP: ffff880852887cd8 R08: 0000000000000000 R09: ffff88085f5d94d0
R10: 0000000000000195 R11: 0000000000000000 R12: ffffffffa01979de
R13: ffff880852887d00 R14: ffffffffa01979de R15: ffff88085f02e840
FS:  0000000000000000(0000) GS:ffff88085f5c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa01979de CR3: 0000000001a0c000 CR4: 00000000001406e0
Stack:
 ffffffff812349b1 ffff880852887cb8 ffff880852887d10 ffff88085f5cd6c2
 ffff880852800a80 ffffffffa01979de ffff880852800a84 0000000000000010
 ffff88085bb28bd8 ffff880852887d38 ffffffff812354f0 ffff880852887d08
Call Trace:
 [<ffffffff812349b1>] ? __xlate_proc_name+0x71/0xd0
 [<ffffffff812354f0>] remove_proc_entry+0x40/0x180
 [<ffffffff815f6811>] ? _raw_spin_lock_irqsave+0x41/0x60
 [<ffffffff813be520>] ? destruct_tty_driver+0x60/0xe0
 [<ffffffff81237c68>] proc_tty_unregister_driver+0x28/0x40
 [<ffffffff813be548>] destruct_tty_driver+0x88/0xe0
 [<ffffffff813be5bd>] tty_driver_kref_put+0x1d/0x20
 [<ffffffff813becca>] release_one_tty+0x5a/0xd0
 [<ffffffff81074159>] process_one_work+0x139/0x420
 [<ffffffff810745a1>] worker_thread+0x121/0x450
 [<ffffffff81074480>] ? process_scheduled_works+0x40/0x40
 [<ffffffff8107a16c>] kthread+0xec/0x110
 [<ffffffff81080000>] ? tg_rt_schedulable+0x210/0x220
 [<ffffffff8107a080>] ? kthread_freezable_should_stop+0x80/0x80
 [<ffffffff815f7292>] ret_from_fork+0x42/0x70
 [<ffffffff8107a080>] ? kthread_freezable_should_stop+0x80/0x80

Signed-off-by: nixiaoming <nixiaoming@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2017-10-20 14:06:45 +02:00

..

array.c

sched/debug: Add explicit TASK_PARKED printing

2017-09-29 11:02:57 +02:00

base.c

mm: treewide: remove GFP_TEMPORARY allocation flag

2017-09-13 18:53:16 -07:00

cmdline.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

consoles.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

cpuinfo.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

devices.c

block: order /proc/devices by major number

2017-07-17 15:42:20 +02:00

fd.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>

2017-03-02 08:42:29 +01:00

fd.h

proc: unsigned file descriptors

2016-09-27 18:47:38 -04:00

generic.c

procfs: use faster rb_first_cached()

2017-09-08 18:26:49 -07:00

inode.c

fs/proc/inode.c: remove cast from memory allocation

2017-05-08 17:15:10 -07:00

internal.h

procfs: use faster rb_first_cached()

2017-09-08 18:26:49 -07:00

interrupts.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

Kconfig

fs, proc: add help for CONFIG_PROC_CHILDREN

2015-07-17 16:39:52 -07:00

kcore.c

fs/proc: kcore: use kcore_list type to check for vmalloc/module address

2017-06-20 12:42:57 +01:00

kmsg.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

loadavg.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/stat.h>

2017-03-02 08:42:34 +01:00

Makefile

fs/proc: Add compiler check for -Wno-override-init to support gcc < 4.2

2016-08-03 12:45:23 -04:00

meminfo.c

mm: rename global_page_state to global_zone_page_state

2017-09-06 17:27:29 -07:00

namespaces.c

pidns: expose task pid_ns_for_children to userspace

2017-05-08 17:15:12 -07:00

nommu.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

page.c

mm: fix KPF_SWAPCACHE in /proc/kpageflags

2017-02-07 12:08:32 -08:00

proc_net.c

procfs: use faster rb_first_cached()

2017-09-08 18:26:49 -07:00

proc_sysctl.c

Merge branch 'akpm' (patches from Andrew)

2017-07-13 12:38:49 -07:00

proc_tty.c

tty fix oops when rmmod 8250

2017-10-20 14:06:45 +02:00

root.c

procfs: use faster rb_first_cached()

2017-09-08 18:26:49 -07:00

self.c

vfs: remove ".readlink = generic_readlink" assignments

2016-12-09 16:45:04 +01:00

softirqs.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

stat.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

task_mmu.c

mm: treewide: remove GFP_TEMPORARY allocation flag

2017-09-13 18:53:16 -07:00

task_nommu.c

procfs: remove unused variable

2017-09-13 18:53:15 -07:00

thread_self.c

vfs: remove ".readlink = generic_readlink" assignments

2016-12-09 16:45:04 +01:00

uptime.c

sched/cputime: Convert kcpustat to nsecs

2017-02-01 09:13:47 +01:00

version.c

fs/proc: don't use module_init for non-modular core code

2014-01-23 16:37:02 -08:00

vmcore.c

userfaultfd: non-cooperative: add event for memory unmaps

2017-02-24 17:46:55 -08:00