mainlining shenanigans
57c5f4df0a
For the target_core_user use case, after the device is unregistered it maybe still opened in user space, then the kernel will crash, like: [ 251.163692] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 251.163820] IP: [<ffffffffc0736213>] show_name+0x23/0x40 [uio] [ 251.163965] PGD 8000000062694067 PUD 62696067 PMD 0 [ 251.164097] Oops: 0000 [#1] SMP ... [ 251.165605] e1000 mptscsih mptbase drm_panel_orientation_quirks dm_mirror dm_region_hash dm_log dm_mod [ 251.166014] CPU: 0 PID: 13380 Comm: tcmu-runner Kdump: loaded Not tainted 3.10.0-916.el7.test.x86_64 #1 [ 251.166381] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017 [ 251.166747] task: ffff971eb91db0c0 ti: ffff971e9e384000 task.ti: ffff971e9e384000 [ 251.167137] RIP: 0010:[<ffffffffc0736213>] [<ffffffffc0736213>] show_name+0x23/0x40 [uio] [ 251.167563] RSP: 0018:ffff971e9e387dc8 EFLAGS: 00010282 [ 251.167978] RAX: 0000000000000000 RBX: ffff971e9e3f8000 RCX: ffff971eb8368d98 [ 251.168408] RDX: ffff971e9e3f8000 RSI: ffffffffc0738084 RDI: ffff971e9e3f8000 [ 251.168856] RBP: ffff971e9e387dd0 R08: ffff971eb8bc0018 R09: 0000000000000000 [ 251.169296] R10: 0000000000001000 R11: ffffffffa09d444d R12: ffffffffa1076e80 [ 251.169750] R13: ffff971e9e387f18 R14: 0000000000000001 R15: ffff971e9cfb1c80 [ 251.170213] FS: 00007ff37d175880(0000) GS:ffff971ebb600000(0000) knlGS:0000000000000000 [ 251.170693] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 251.171248] CR2: 0000000000000008 CR3: 00000000001f6000 CR4: 00000000003607f0 [ 251.172071] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 251.172640] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 251.173236] Call Trace: [ 251.173789] [<ffffffffa0c9b2d3>] dev_attr_show+0x23/0x60 [ 251.174356] [<ffffffffa0f561b2>] ? mutex_lock+0x12/0x2f [ 251.174892] [<ffffffffa0ac6d9f>] sysfs_kf_seq_show+0xcf/0x1f0 [ 251.175433] [<ffffffffa0ac54e6>] kernfs_seq_show+0x26/0x30 [ 251.175981] [<ffffffffa0a63be0>] seq_read+0x110/0x3f0 [ 251.176609] [<ffffffffa0ac5d45>] kernfs_fop_read+0xf5/0x160 [ 251.177158] [<ffffffffa0a3d3af>] vfs_read+0x9f/0x170 [ 251.177707] [<ffffffffa0a3e27f>] SyS_read+0x7f/0xf0 [ 251.178268] [<ffffffffa0f648af>] system_call_fastpath+0x1c/0x21 [ 251.178823] Code: 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 d3 e8 7e 96 56 e0 48 8b 80 d8 02 00 00 48 89 df 48 c7 c6 84 80 73 c0 <48> 8b 50 08 31 c0 e8 e2 67 44 e0 5b 48 98 5d c3 0f 1f 00 66 2e [ 251.180115] RIP [<ffffffffc0736213>] show_name+0x23/0x40 [uio] [ 251.180820] RSP <ffff971e9e387dc8> [ 251.181473] CR2: 0000000000000008 CC: Hamish Martin <hamish.martin@alliedtelesis.co.nz> CC: Mike Christie <mchristi@redhat.com> Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Signed-off-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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.