Go to file
Xiubo Li c22adc0b0c tcmu: fix crash when removing the tcmu device
Before the nl REMOVE msg has been sent to the userspace, the ring's
and other resources have been released, but the userspace maybe still
using them. And then we can see the crash messages like:

ring broken, not handling completions
BUG: unable to handle kernel paging request at ffffffffffffffd0
IP: tcmu_handle_completions+0x134/0x2f0 [target_core_user]
PGD 11bdc0c067
P4D 11bdc0c067
PUD 11bdc0e067
PMD 0

Oops: 0000 [#1] SMP
cmd_id not found, ring is broken
RIP: 0010:tcmu_handle_completions+0x134/0x2f0 [target_core_user]
RSP: 0018:ffffb8a2d8983d88 EFLAGS: 00010296
RAX: 0000000000000000 RBX: ffffb8a2aaa4e000 RCX: 00000000ffffffff
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000220
R10: 0000000076c71401 R11: ffff8d2e76c713f0 R12: ffffb8a2aad56bc0
R13: 000000000000001c R14: ffff8d2e32c90000 R15: ffff8d2e76c713f0
FS:  00007f411ffff700(0000) GS:ffff8d1e7fdc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd0 CR3: 0000001027070000 CR4:
00000000001406e0
Call Trace:
? tcmu_irqcontrol+0x2a/0x40 [target_core_user]
? uio_write+0x7b/0xc0 [uio]
? __vfs_write+0x37/0x150
? __getnstimeofday64+0x3b/0xd0
? vfs_write+0xb2/0x1b0
? syscall_trace_enter+0x1d0/0x2b0
? SyS_write+0x55/0xc0
? do_syscall_64+0x67/0x150
? entry_SYSCALL64_slow_path+0x25/0x25
Code: 41 5d 41 5e 41 5f 5d c3 83 f8 01 0f 85 cf 01 00
00 48 8b 7d d0 e8 dd 5c 1d f3 41 0f b7 74 24 04 48 8b
7d c8 31 d2 e8 5c c7 1b f3 <48> 8b 7d d0 49 89 c7 c6 07
00 0f 1f 40 00 4d 85 ff 0f 84 82 01  RIP:
tcmu_handle_completions+0x134/0x2f0 [target_core_user]
RSP: ffffb8a2d8983d88
CR2: ffffffffffffffd0

And the crash also could happen in tcmu_page_fault and other places.

Signed-off-by: Zhang Zhuoyu <zhangzhuoyu@cmss.chinamobile.com>
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-11-04 14:48:21 -07:00
Documentation Staging/IIO fixes for 4.14-rc6 2017-10-23 06:37:16 -04:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-22 06:58:23 -04:00
block bio_copy_user_iov(): don't ignore ->iov_offset 2017-10-10 23:55:14 -04:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto Merge commit 'tags/keys-fixes-20171018' into fixes-v4.14-rc5 2017-10-19 12:28:38 +11:00
drivers tcmu: fix crash when removing the tcmu device 2017-11-04 14:48:21 -07:00
firmware firmware: Restore support for built-in firmware 2017-09-16 10:58:48 -07:00
fs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-10-21 21:39:18 -04:00
include target: add sense code INSUFFICIENT REGISTRATION RESOURCES 2017-11-04 14:45:23 -07:00
init Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ipc fix a typo in put_compat_shm_info() 2017-09-25 20:41:46 -04:00
kernel Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-22 06:54:42 -04:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-21 22:44:48 -04:00
mm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-21 22:44:48 -04:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-21 22:44:48 -04:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-10-21 22:44:48 -04:00
scripts Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2017-10-22 16:19:12 -04:00
security commoncap: move assignment of fs_ns to avoid null pointer dereference 2017-10-19 13:09:33 +11:00
sound ALSA: hda - Fix incorrect TLV callback check introduced during set_fs() removal 2017-10-18 12:27:00 +02:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-22 06:52:53 -04:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt Revert "KVM: Don't accept obviously wrong gsi values via KVM_IRQFD" 2017-09-19 08:37:17 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap Update James Hogan's email address 2017-10-04 17:11:53 -07:00
COPYING
CREDITS selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS USB/PHY fixes for 4.14-rc6 2017-10-23 06:33:05 -04:00
Makefile Linux 4.14-rc6 2017-10-23 06:49:47 -04:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.