Go to file
Farhan Ali b49bdc8602 vfio-ccw: Release any channel program when releasing/removing vfio-ccw mdev
When releasing the vfio-ccw mdev, we currently do not release
any existing channel program and its pinned pages. This can
lead to the following warning:

[1038876.561565] WARNING: CPU: 2 PID: 144727 at drivers/vfio/vfio_iommu_type1.c:1494 vfio_sanity_check_pfn_list+0x40/0x70 [vfio_iommu_type1]

....

1038876.561921] Call Trace:
[1038876.561935] ([<00000009897fb870>] 0x9897fb870)
[1038876.561949]  [<000003ff8013bf62>] vfio_iommu_type1_detach_group+0xda/0x2f0 [vfio_iommu_type1]
[1038876.561965]  [<000003ff8007b634>] __vfio_group_unset_container+0x64/0x190 [vfio]
[1038876.561978]  [<000003ff8007b87e>] vfio_group_put_external_user+0x26/0x38 [vfio]
[1038876.562024]  [<000003ff806fc608>] kvm_vfio_group_put_external_user+0x40/0x60 [kvm]
[1038876.562045]  [<000003ff806fcb9e>] kvm_vfio_destroy+0x5e/0xd0 [kvm]
[1038876.562065]  [<000003ff806f63fc>] kvm_put_kvm+0x2a4/0x3d0 [kvm]
[1038876.562083]  [<000003ff806f655e>] kvm_vm_release+0x36/0x48 [kvm]
[1038876.562098]  [<00000000003c2dc4>] __fput+0x144/0x228
[1038876.562113]  [<000000000016ee82>] task_work_run+0x8a/0xd8
[1038876.562125]  [<000000000014c7a8>] do_exit+0x5d8/0xd90
[1038876.562140]  [<000000000014d084>] do_group_exit+0xc4/0xc8
[1038876.562155]  [<000000000015c046>] get_signal+0x9ae/0xa68
[1038876.562169]  [<0000000000108d66>] do_signal+0x66/0x768
[1038876.562185]  [<0000000000b9e37e>] system_call+0x1ea/0x2d8
[1038876.562195] 2 locks held by qemu-system-s39/144727:
[1038876.562205]  #0: 00000000537abaf9 (&container->group_lock){++++}, at: __vfio_group_unset_container+0x3c/0x190 [vfio]
[1038876.562230]  #1: 00000000670008b5 (&iommu->lock){+.+.}, at: vfio_iommu_type1_detach_group+0x36/0x2f0 [vfio_iommu_type1]
[1038876.562250] Last Breaking-Event-Address:
[1038876.562262]  [<000003ff8013aa24>] vfio_sanity_check_pfn_list+0x3c/0x70 [vfio_iommu_type1]
[1038876.562272] irq event stamp: 4236481
[1038876.562287] hardirqs last  enabled at (4236489): [<00000000001cee7a>] console_unlock+0x6d2/0x740
[1038876.562299] hardirqs last disabled at (4236496): [<00000000001ce87e>] console_unlock+0xd6/0x740
[1038876.562311] softirqs last  enabled at (4234162): [<0000000000b9fa1e>] __do_softirq+0x556/0x598
[1038876.562325] softirqs last disabled at (4234153): [<000000000014e4cc>] irq_exit+0xac/0x108
[1038876.562337] ---[ end trace 6c96d467b1c3ca06 ]---

Similarly we do not free the channel program when we are removing
the vfio-ccw device. Let's fix this by resetting the device and freeing
the channel program and pinned pages in the release path. For the remove
path we can just quiesce the device, since in the remove path the mediated
device is going away for good and so we don't need to do a full reset.

Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <ae9f20dc8873f2027f7b3c5d2aaa0bdfe06850b8.1554756534.git.alifm@linux.ibm.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-04-24 14:18:51 +02:00
Documentation vfs: Update mount API docs 2019-03-28 08:54:20 -07:00
LICENSES LICENSES: Add GCC runtime library exception text 2019-01-16 14:54:15 -07:00
arch s390/cpum_cf_diag: Add support for CPU-MF SVN 6 2019-04-23 16:30:06 +02:00
block io_uring-20190323 2019-03-23 10:25:12 -07:00
certs kexec, KEYS: Make use of platform keyring for signature verify 2019-02-04 17:34:07 -05:00
crypto lib/lzo: separate lzo-rle from lzo 2019-03-07 18:32:03 -08:00
drivers vfio-ccw: Release any channel program when releasing/removing vfio-ccw mdev 2019-04-24 14:18:51 +02:00
fs afs: Fix StoreData op marshalling 2019-03-28 08:54:20 -07:00
include vfio-ccw: add handling for async channel instructions 2019-04-24 14:18:51 +02:00
init init/main: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
ipc Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 14:08:19 -07:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-27 12:22:57 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-27 12:22:57 -07:00
mm device-dax for 5.1 2019-03-16 13:05:32 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-27 12:22:57 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-11 08:54:01 -07:00
scripts kconfig: remove stale lxdialog/.gitignore 2019-03-17 15:47:02 +09:00
security selinux: fix NULL dereference in policydb_destroy() 2019-03-18 12:19:48 -04:00
sound sound fixes for 5.1-rc2 2019-03-22 14:04:38 -07:00
tools s390/rseq: use trap4 for RSEQ_SIG 2019-04-10 17:48:34 +02:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt ARM: some cleanups, direct physical timer assignment, cache sanitization 2019-03-15 15:00:28 -07:00
.clang-format Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 13:43:42 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap .mailmap: Add Mathieu Othacehe 2019-02-21 11:41:19 +00:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Char/Misc driver patches for 5.1-rc1 2019-03-06 14:18:59 -08:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS io_uring-20190323 2019-03-23 10:25:12 -07:00
Makefile Linux 5.1-rc2 2019-03-24 14:02:26 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.

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.