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path: root/drivers/char/virtio_console.c
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* virtio_console: silence a static checker warningDan Carpenter2015-05-241-2/+2
| | | | | | | | | My static checker complains that this sprintf() can overflow but really it can't. Just silence the warning by using snprintf(). Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* virtio_console: Use bool function return values of true/false not 1/0Joe Perches2015-04-031-1/+1
| | | | | | | | Use the normal return values for bool functions Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* virtio_console: avoid config access from irqMichael S. Tsirkin2015-03-051-0/+16
| | | | | | | | | | | | when multiport is off, virtio console invokes config access from irq context, config access is blocking on s390. Fix this up by scheduling work from config irq - similar to what we do for multiport configs. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
* virtio_console: init work unconditionallyMichael S. Tsirkin2015-03-051-1/+2
| | | | | | | | | | when multiport is off, we don't initialize config work, but we then cancel uninitialized control_work on freeze. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
* virtio: don't require a config space on the console device.Rusty Russell2015-02-111-1/+4
| | | | | | Strictly, it's only needed when we have features (size or multiport). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio/console: verify device has config spaceMichael S. Tsirkin2015-01-211-0/+6
| | | | | | | | | | Some devices might not implement config space access (e.g. remoteproc used not to - before 3.9). virtio/console needs config space access so make it fail gracefully if not there. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio_console: fix sparse warningsMichael S. Tsirkin2014-12-091-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | CHECK drivers/char/virtio_console.c drivers/char/virtio_console.c:687:36: warning: incorrect type in argument 1 (different address spaces) drivers/char/virtio_console.c:687:36: expected void [noderef] <asn:1>*to drivers/char/virtio_console.c:687:36: got char *out_buf drivers/char/virtio_console.c:790:35: warning: incorrect type in argument 2 (different address spaces) drivers/char/virtio_console.c:790:35: expected char *out_buf drivers/char/virtio_console.c:790:35: got char [noderef] <asn:1>*ubuf fill_readbuf is reused with both kernel and userspace pointers, depending on value of to_user flag. Tag address parameter as __user, and cast to/from regular pointer type when we know it's safe. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* virtio: drop VIRTIO_F_VERSION_1 from driversMichael S. Tsirkin2014-12-091-1/+0
| | | | | | | | | | | Core activates this bit automatically now, drop it from drivers that set it explicitly. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* virtio_console: virtio 1.0 supportMichael S. Tsirkin2014-12-091-12/+17
| | | | | | | | | | Pretty straight-forward, just use accessors for all fields. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* virtio: use u32, not bitmap for featuresMichael S. Tsirkin2014-12-091-1/+1
| | | | | | | | | | | | | | | | | | | It seemed like a good idea to use bitmap for features in struct virtio_device, but it's actually a pain, and seems to become even more painful when we get more than 32 feature bits. Just change it to a u32 for now. Based on patch by Rusty. Suggested-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* virtio_console: move early VQ enablementCornelia Huck2014-11-131-2/+2
| | | | | | | | | | | | | | | | | | Commit f5866db6 (virtio_console: enable VQs early) tried to make sure that DRIVER_OK was set when virtio_console started using its virtqueues. Doing this in add_port(), however, means that we try to set DRIVER_OK again when when a port is dynamically added after the probe function is done. Let's move virtio_device_ready() to the probe function just before trying to use the virtqueues instead. This is fine as nothing can fail inbetween. Reported-by: Thomas Graf <tgraf@suug.ch> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* virtio_console: enable VQs early on restoreMichael S. Tsirkin2014-10-151-0/+2
| | | | | | | | | | | | virtio spec requires drivers to set DRIVER_OK before using VQs. This is set automatically after resume returns, virtio console violated this rule by adding inbufs, which causes the VQ to be used directly within restore. To fix, call virtio_device_ready before using VQs. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio_console: enable VQs earlyMichael S. Tsirkin2014-10-151-0/+2
| | | | | | | | | | | | virtio spec requires drivers to set DRIVER_OK before using VQs. This is set automatically after probe returns, virtio console violated this rule by adding inbufs, which causes the VQ to be used directly within probe. To fix, call virtio_device_ready before using VQs. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: remove unnecessary null test before debugfs_remove_recursiveFabian Frederick2014-07-271-4/+2
| | | | | | | | | | | Fix checkpatch warning: WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required Cc: Arnd Bergmann <arnd@arndb.de> Cc: virtualization@lists.linux-foundation.org Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* pipe: kill ->map() and ->unmap()Al Viro2014-04-011-2/+2
| | | | | | all pipe_buffer_operations have the same instances of those... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fix a kmap leak in virtio_consoleAl Viro2014-02-091-6/+3
| | | | | | | | | While we are at it, don't do kmap() under kmap_atomic(), *especially* for a page we'd allocated with GFP_KERNEL. It's spelled "page_address", and had that been more than that, we'd have a real trouble - kmap_high() can block, and doing that while holding kmap_atomic() is a Bad Idea(tm). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* virtio_console: verify if queue is broken after virtqueue_get_buf()Heinz Graalfs2013-10-291-2/+4
| | | | | | | | If virtqueue_get_buf() returns with a NULL pointer it should be verified if the virtqueue is broken, in order to avoid loop calling cpu_relax(). Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: use size-based config accessors.Rusty Russell2013-10-171-10/+5
| | | | | | | | | This lets the transport do endian conversion if necessary, and insulates the drivers from the difference. Most drivers can use the simple helpers virtio_cread() and virtio_cwrite(). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: pm: use CONFIG_PM_SLEEP instead of CONFIG_PMAaron Lu2013-09-231-2/+2
| | | | | | | | | | | The freeze and restore functions defined in virtio drivers are used for suspend and hibernate, so CONFIG_PM_SLEEP is more appropriate than CONFIG_PM. This patch replace all CONFIG_PM with CONFIG_PM_SLEEP for virtio drivers that implement freeze and restore callbacks. Signed-off-by: Aaron Lu <aaron.lu@intel.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: console: prevent use-after-free of port name in port unplugAmit Shah2013-08-091-2/+1
| | | | | | | | | Remove the debugfs path before freeing port->name, to prevent a possible use-after-free. Reported-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Merge branch 'master' into virtio-nextRusty Russell2013-08-091-22/+48
|\ | | | | | | | | | | | | | | The next commit gets conflicts because it relies on patches which were cc:stable and thus had to be merged into Linus' tree before the coming merge window. So pull in master now. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: return -ENODEV on all read operations after unplugAmit Shah2013-07-291-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a port gets unplugged while a user is blocked on read(), -ENODEV is returned. However, subsequent read()s returned 0, indicating there's no host-side connection (but not indicating the device went away). This also happened when a port was unplugged and the user didn't have any blocking operation pending. If the user didn't monitor the SIGIO signal, they won't have a chance to find out if the port went away. Fix by returning -ENODEV on all read()s after the port gets unplugged. write() already behaves this way. CC: <stable@vger.kernel.org> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: fix raising SIGIO after port unplugAmit Shah2013-07-291-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SIGIO should be sent when a port gets unplugged. It should only be sent to prcesses that have the port opened, and have asked for SIGIO to be delivered. We were clearing out guest_connected before calling send_sigio_to_port(), resulting in a sigio not getting sent to processes. Fix by setting guest_connected to false after invoking the sigio function. CC: <stable@vger.kernel.org> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: clean up port data immediately at time of unplugAmit Shah2013-07-291-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We used to keep the port's char device structs and the /sys entries around till the last reference to the port was dropped. This is actually unnecessary, and resulted in buggy behaviour: 1. Open port in guest 2. Hot-unplug port 3. Hot-plug a port with the same 'name' property as the unplugged one This resulted in hot-plug being unsuccessful, as a port with the same name already exists (even though it was unplugged). This behaviour resulted in a warning message like this one: -------------------8<--------------------------------------- WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted) Hardware name: KVM sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1' Call Trace: [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60 [<ffffffff812734b4>] ? kobject_add+0x44/0x70 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0 [<ffffffff8134b389>] ? device_add+0xc9/0x650 -------------------8<--------------------------------------- Instead of relying on guest applications to release all references to the ports, we should go ahead and unregister the port from all the core layers. Any open/read calls on the port will then just return errors, and an unplug/plug operation on the host will succeed as expected. This also caused buggy behaviour in case of the device removal (not just a port): when the device was removed (which means all ports on that device are removed automatically as well), the ports with active users would clean up only when the last references were dropped -- and it would be too late then to be referencing char device pointers, resulting in oopses: -------------------8<--------------------------------------- PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat" #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5 [exception RIP: strlen+2] RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000 RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030 RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500 R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10 R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb #9 [ffff88011b9d5de0] device_del at ffffffff813440c7 -------------------8<--------------------------------------- So clean up when we have all the context, and all that's left to do when the references to the port have dropped is to free up the port struct itself. CC: <stable@vger.kernel.org> Reported-by: chayang <chayang@redhat.com> Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com> Reported-by: FuXiangChun <xfu@redhat.com> Reported-by: Qunfang Zhang <qzhang@redhat.com> Reported-by: Sibiao Luo <sluo@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: fix race in port_fops_open() and port unplugAmit Shah2013-07-291-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Between open() being called and processed, the port can be unplugged. Check if this happened, and bail out. A simple test script to reproduce this is: while true; do for i in $(seq 1 100); do echo $i > /dev/vport0p3; done; done; This opens and closes the port a lot of times; unplugging the port while this is happening triggers the bug. CC: <stable@vger.kernel.org> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio: console: fix race with port unplug and open/closeAmit Shah2013-07-291-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | There's a window between find_port_by_devt() returning a port and us taking a kref on the port, where the port could get unplugged. Fix it by taking the reference in find_port_by_devt() itself. Problem reported and analyzed by Mateusz Guzik. CC: <stable@vger.kernel.org> Reported-by: Mateusz Guzik <mguzik@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio/console: Add pipe_lock/unlock for splice_writeYoshihiro YUNOMAE2013-07-231-5/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add pipe_lock/unlock for splice_write to avoid oops by following competition: (1) An application gets fds of a trace buffer, virtio-serial, pipe. (2) The application does fork() (3) The processes execute splice_read(trace buffer) and splice_write(virtio-serial) via same pipe. <parent> <child> get fds of a trace buffer, virtio-serial, pipe | fork()----------create--------+ | | splice(read) | ---+ splice(write) | +-- no competition | splice(read) | | splice(write) ---+ | | splice(read) | splice(write) splice(read) ------ competition | splice(write) Two processes share a pipe_inode_info structure. If the child execute splice(read) when the parent tries to execute splice(write), the structure can be broken. Existing virtio-serial driver does not get lock for the structure in splice_write, so this competition will induce oops. <oops messages> BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 PGD 7223e067 PUD 72391067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: lockd bnep bluetooth rfkill sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer snd soundcore pcspkr virtio_net virtio_balloon i2c_piix4 i2c_core microcode uinput floppy CPU: 0 PID: 1072 Comm: compete-test Not tainted 3.10.0ws+ #55 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880071b98000 ti: ffff88007b55e000 task.ti: ffff88007b55e000 RIP: 0010:[<ffffffff811a6b5f>] [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 RSP: 0018:ffff88007b55fd78 EFLAGS: 00010287 RAX: 0000000000000000 RBX: ffff88007b55fe20 RCX: 0000000000000000 RDX: 0000000000001000 RSI: ffff88007a95ba30 RDI: ffff880036f9e6c0 RBP: ffff88007b55fda8 R08: 00000000000006ec R09: ffff880077626708 R10: 0000000000000003 R11: ffffffff8139ca59 R12: ffff88007a95ba30 R13: 0000000000000000 R14: ffffffff8139dd00 R15: ffff880036f9e6c0 FS: 00007f2e2e3a0740(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000018 CR3: 0000000071bd1000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffffffff8139ca59 ffff88007b55fe20 ffff880036f9e6c0 ffffffff8139dd00 ffff8800776266c0 ffff880077626708 ffff88007b55fde8 ffffffff811a6e8e ffff88007b55fde8 ffffffff8139ca59 ffff880036f9e6c0 ffff88007b55fe20 Call Trace: [<ffffffff8139ca59>] ? alloc_buf.isra.13+0x39/0xb0 [<ffffffff8139dd00>] ? virtcons_restore+0x100/0x100 [<ffffffff811a6e8e>] __splice_from_pipe+0x7e/0x90 [<ffffffff8139ca59>] ? alloc_buf.isra.13+0x39/0xb0 [<ffffffff8139d739>] port_fops_splice_write+0xe9/0x140 [<ffffffff8127a3f4>] ? selinux_file_permission+0xc4/0x120 [<ffffffff8139d650>] ? wait_port_writable+0x1b0/0x1b0 [<ffffffff811a6fe0>] do_splice_from+0xa0/0x110 [<ffffffff811a951f>] SyS_splice+0x5ff/0x6b0 [<ffffffff8161facf>] tracesys+0xdd/0xe2 Code: 49 8b 87 80 00 00 00 4c 8d 24 d0 8b 53 04 41 8b 44 24 0c 4d 8b 6c 24 10 39 d0 89 03 76 02 89 13 49 8b 44 24 10 4c 89 e6 4c 89 ff <ff> 50 18 85 c0 0f 85 aa 00 00 00 48 89 da 4c 89 e6 4c 89 ff 41 RIP [<ffffffff811a6b5f>] splice_from_pipe_feed+0x6f/0x130 RSP <ffff88007b55fd78> CR2: 0000000000000018 ---[ end trace 24572beb7764de59 ]--- V2: Fix a locking problem for error V3: Add Reviewed-by lines and stable@ line in sign-off area Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Amit Shah <amit.shah@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio/console: Quit from splice_write if pipe->nrbufs is 0Yoshihiro YUNOMAE2013-07-231-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quit from splice_write if pipe->nrbufs is 0 for avoiding oops in virtio-serial. When an application was doing splice from a kernel buffer to virtio-serial on a guest, the application received signal(SIGINT). This situation will normally happen, but the kernel executed a kernel panic by oops as follows: BUG: unable to handle kernel paging request at ffff882071c8ef28 IP: [<ffffffff812de48f>] sg_init_table+0x2f/0x50 PGD 1fac067 PUD 0 Oops: 0000 [#1] SMP Modules linked in: lockd sunrpc bnep bluetooth rfkill ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer snd microcode virtio_balloon virtio_net pcspkr soundcore i2c_piix4 i2c_core uinput floppy CPU: 1 PID: 908 Comm: trace-cmd Not tainted 3.10.0+ #49 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880071c64650 ti: ffff88007bf24000 task.ti: ffff88007bf24000 RIP: 0010:[<ffffffff812de48f>] [<ffffffff812de48f>] sg_init_table+0x2f/0x50 RSP: 0018:ffff88007bf25dd8 EFLAGS: 00010286 RAX: 0000001fffffffe0 RBX: ffff882071c8ef28 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880071c8ef48 RBP: ffff88007bf25de8 R08: ffff88007fd15d40 R09: ffff880071c8ef48 R10: ffffea0001c71040 R11: ffffffff8139c555 R12: 0000000000000000 R13: ffff88007506a3c0 R14: ffff88007c862500 R15: ffff880071c8ef00 FS: 00007f0a3646c740(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff882071c8ef28 CR3: 000000007acbb000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff880071c8ef48 ffff88007bf25e20 ffff88007bf25e88 ffffffff8139d6fa ffff88007bf25e28 ffffffff8127a3f4 0000000000000000 0000000000000000 ffff880071c8ef48 0000100000000000 0000000000000003 ffff88007bf25e08 Call Trace: [<ffffffff8139d6fa>] port_fops_splice_write+0xaa/0x130 [<ffffffff8127a3f4>] ? selinux_file_permission+0xc4/0x120 [<ffffffff8139d650>] ? wait_port_writable+0x1b0/0x1b0 [<ffffffff811a6fe0>] do_splice_from+0xa0/0x110 [<ffffffff811a951f>] SyS_splice+0x5ff/0x6b0 [<ffffffff8161f8c2>] system_call_fastpath+0x16/0x1b Code: c1 e2 05 48 89 e5 48 83 ec 10 4c 89 65 f8 41 89 f4 31 f6 48 89 5d f0 48 89 fb e8 8d ce ff ff 41 8d 44 24 ff 48 c1 e0 05 48 01 c3 <48> 8b 03 48 83 e0 fe 48 83 c8 02 48 89 03 48 8b 5d f0 4c 8b 65 RIP [<ffffffff812de48f>] sg_init_table+0x2f/0x50 RSP <ffff88007bf25dd8> CR2: ffff882071c8ef28 ---[ end trace 86323505eb42ea8f ]--- It seems to induce pagefault in sg_init_tabel() when pipe->nrbufs is equal to zero. This may happen in a following situation: (1) The application normally does splice(read) from a kernel buffer, then does splice(write) to virtio-serial. (2) The application receives SIGINT when is doing splice(read), so splice(read) is failed by EINTR. However, the application does not finish the operation. (3) The application tries to do splice(write) without pipe->nrbufs. (4) The virtio-console driver tries to touch scatterlist structure sgl in sg_init_table(), but the region is out of bound. To avoid the case, a kernel should check whether pipe->nrbufs is empty or not when splice_write is executed in the virtio-console driver. V3: Add Reviewed-by lines and stable@ line in sign-off area. Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Amit Shah <amit.shah@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: cleanup an error messageDan Carpenter2013-07-301-4/+2
| | | | | | | | | | | | | | | | The PTR_ERR(NULL) here is not useful. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: fix locking around send_sigio_to_port()Amit Shah2013-07-291-3/+5
| | | | | | | | | | | | | | | | | | send_sigio_to_port() checks the value of guest_connected, which we always modify under the inbuf_lock; make sure invocations of send_sigio_to_port() have take the inbuf_lock around the call. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: add locking in port unplug pathAmit Shah2013-07-291-0/+2
| | | | | | | | | | | | | | | | | | Port unplug can race with close() in port_fops_release(). port_fops_release() already takes the necessary locks, ensure unplug_port() does that too. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: add locks around buffer removal in port unplug pathAmit Shah2013-07-291-2/+6
|/ | | | | | | | The removal functions act on the vqs, and the vq operations need to be locked. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds2013-05-021-7/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio & lguest updates from Rusty Russell: "Lots of virtio work which wasn't quite ready for last merge window. Plus I dived into lguest again, reworking the pagetable code so we can move the switcher page: our fixmaps sometimes take more than 2MB now..." Ugh. Annoying conflicts with the tcm_vhost -> vhost_scsi rename. Hopefully correctly resolved. * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (57 commits) caif_virtio: Remove bouncing email addresses lguest: improve code readability in lg_cpu_start. virtio-net: fill only rx queues which are being used lguest: map Switcher below fixmap. lguest: cache last cpu we ran on. lguest: map Switcher text whenever we allocate a new pagetable. lguest: don't share Switcher PTE pages between guests. lguest: expost switcher_pages array (as lg_switcher_pages). lguest: extract shadow PTE walking / allocating. lguest: make check_gpte et. al return bool. lguest: assume Switcher text is a single page. lguest: rename switcher_page to switcher_pages. lguest: remove RESERVE_MEM constant. lguest: check vaddr not pgd for Switcher protection. lguest: prepare to make SWITCHER_ADDR a variable. virtio: console: replace EMFILE with EBUSY for already-open port virtio-scsi: reset virtqueue affinity when doing cpu hotplug virtio-scsi: introduce multiqueue support virtio-scsi: push vq lock/unlock into virtscsi_vq_done virtio-scsi: pass struct virtio_scsi to virtqueue completion function ...
| * virtio: console: replace EMFILE with EBUSY for already-open portAmit Shah2013-04-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Returning EMFILE (process has too many open files) is incorrect to indicate a port is already open by another process. Use EBUSY for that. This does change what we report to userspace, but I believe userspace can look at it this way: it gets EBUSY, a new error code, instead of EMFILE. It's still an error, and that's not changing. Reported-by: Mateusz Guzik <mguzik@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: make local symbols staticWei Yongjun2013-04-081-3/+3
| | | | | | | | | | | | | | | | Those symbols only used within this file, and should be static. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: use simplified virtqueue accessors.Rusty Russell2013-03-201-3/+3
| | | | | | | | | | | | | | We never add buffers with input and output parts, so use the new accessors. Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio: console: add locking around c_ovq operationsAmit Shah2013-03-301-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When multiple ovq operations are being performed (lots of open/close operations on virtio_console fds), the __send_control_msg() function can get confused without locking. A simple recipe to cause badness is: * create a QEMU VM with two virtio-serial ports * in the guest, do while true;do echo abc >/dev/vport0p1;done while true;do echo edf >/dev/vport0p2;done In one run, this caused a panic in __send_control_msg(). In another, I got virtio_console virtio0: control-o:id 0 is not a head! This also results repeated messages similar to these on the host: qemu-kvm: virtio-serial-bus: Unexpected port id 478762112 for device virtio-serial-bus.0 qemu-kvm: virtio-serial-bus: Unexpected port id 478762368 for device virtio-serial-bus.0 Reported-by: FuXiangChun <xfu@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Reviewed-by: Asias He <asias@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
* | virtio: console: rename cvq_lock to c_ivq_lockAmit Shah2013-03-301-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The cvq_lock was taken for the c_ivq. Rename the lock to make that obvious. We'll also add a lock around the c_ovq in the next commit, so there's no ambiguity. Signed-off-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Asias He <asias@redhat.com> Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
* | Revert "virtio_console: Initialize guest_connected=true for rproc_serial"Sjur Brændeland2013-03-181-6/+16
|/ | | | | | | | | | | | | This reverts commit 8078db789a92b10ff6e2d713231b5367e014c53b, and adds a lengthy comment explaining the problem area. The reverted patch caused opening of ports to fail for rproc_serial. In probe guest_connected was set to true, but port_fops_open() fails with -EMFILE if guest_connected already is true. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds2013-02-261-14/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio updates from Rusty Russell: "All trivial, thanks to the stuff which didn't quite make it time" * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: virtio_console: Initialize guest_connected=true for rproc_serial virtio: use module_virtio_driver. virtio: Add module driver macro for virtio drivers. virtio_console: Use virtio device index to generate port name virtio: make pci_device_id const virtio: make config_ops const virtio-mmio: fix wrong comment about register offset virtio_console: Let unconnected rproc device receive data.
| * virtio_console: Initialize guest_connected=true for rproc_serialSjur Brændeland2013-02-131-5/+2
| | | | | | | | | | | | | | | | | | When rproc_serial is initialized, guest_connected should be set to true. We can then revert the extra checks introduced in commit: "virtio_console: Let unconnected rproc device receive data." Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Use virtio device index to generate port nameSjur Brændeland2013-02-121-13/+3
| | | | | | | | | | | | | | | | | | | | Use virtio device index for creating unique device port names. Current index allocation in virtio is based on a monotonically increasing variable "index". A better handling of this is to use device index which is allocated by ida. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Let unconnected rproc device receive data.Sjur Brændeland2013-01-221-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | Allow rproc serial ports to receive data before the port is connected. Rproc serial ports usually talk to very simple remote devices with no control queue managing open/close events. So we must let remote devices write to the virtio ring even if the device is not yet fully initialized. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | virtio_console: Don't access uninitialized data.Sjur Brændeland2013-02-071-1/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't access uninitialized work-queue when removing device. The work queue is initialized only if the device multi-queue. So don't call cancel_work unless this is a multi-queue device. This fixes the following panic: Kernel panic - not syncing: BUG! Call Trace: 62031b28: [<6026085d>] panic+0x16b/0x2d3 62031b30: [<6004ef5e>] flush_work+0x0/0x1d7 62031b60: [<602606f2>] panic+0x0/0x2d3 62031b68: [<600333b0>] memcpy+0x0/0x140 62031b80: [<6002d58a>] unblock_signals+0x0/0x84 62031ba0: [<602609c5>] printk+0x0/0xa0 62031bd8: [<60264e51>] __mutex_unlock_slowpath+0x13d/0x148 62031c10: [<6004ef5e>] flush_work+0x0/0x1d7 62031c18: [<60050234>] try_to_grab_pending+0x0/0x17e 62031c38: [<6004e984>] get_work_gcwq+0x71/0x8f 62031c48: [<60050539>] __cancel_work_timer+0x5b/0x115 62031c78: [<628acc85>] unplug_port+0x0/0x191 [virtio_console] 62031c98: [<6005061c>] cancel_work_sync+0x12/0x14 62031ca8: [<628ace96>] virtcons_remove+0x80/0x15c [virtio_console] 62031ce8: [<628191de>] virtio_dev_remove+0x1e/0x7e [virtio] 62031d08: [<601cf242>] __device_release_driver+0x75/0xe4 62031d28: [<601cf2dd>] device_release_driver+0x2c/0x40 62031d48: [<601ce0dd>] driver_unbind+0x7d/0xc6 62031d88: [<601cd5d9>] drv_attr_store+0x27/0x29 62031d98: [<60115f61>] sysfs_write_file+0x100/0x14d 62031df8: [<600b737d>] vfs_write+0xcb/0x184 62031e08: [<600b58b8>] filp_close+0x88/0x94 62031e38: [<600b7686>] sys_write+0x59/0x88 62031e88: [<6001ced1>] handle_syscall+0x5d/0x80 62031ea8: [<60030a74>] userspace+0x405/0x531 62031f08: [<600d32cc>] sys_dup+0x0/0x5e 62031f28: [<601b11d6>] strcpy+0x0/0x18 62031f38: [<600be46c>] do_execve+0x10/0x12 62031f48: [<600184c7>] run_init_process+0x43/0x45 62031fd8: [<60019a91>] new_thread_handler+0xba/0xbc Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Cc: stable@kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Drivers: char: remove __dev* attributes.Greg Kroah-Hartman2013-01-031-5/+1
| | | | | | | | | | | | | | | | | CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: David Airlie <airlied@linux.ie> Cc: Matt Mackall <mpm@selenic.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'virtio-next-for-linus' of ↵Linus Torvalds2012-12-201-99/+230
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
| * virtio_console: Add support for remoteproc serialSjur Brændeland2012-12-181-23/+169
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a simple serial connection driver called VIRTIO_ID_RPROC_SERIAL (11) for communicating with a remote processor in an asymmetric multi-processing configuration. This implementation reuses the existing virtio_console implementation, and adds support for DMA allocation of data buffers and disables use of tty console and the virtio control queue. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Merge struct buffer_token into struct port_bufferSjur Brændeland2012-12-181-76/+53
| | | | | | | | | | | | | | | | | | | | | | | | Refactoring the splice functionality by unifying the approach for sending scatter-lists and regular buffers. This simplifies buffer handling and reduces code size. Splice will now allocate a port_buffer and send_buf() and free_buf() can always be used for any buffer. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| * virtio_console: Free buffers from out-queue upon closesjur.brandeland@stericsson.com2012-12-181-0/+4
| | | | | | | | | | | | | | | | Free pending output buffers from the virtio out-queue when host has acknowledged port_close. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (rebased & cut down)
| * virtio_console: Use kmalloc instead of kzallocSjur Brændeland2012-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | Avoid the more cpu expensive kzalloc when allocating buffers. Originally kzalloc was intended for isolating the guest from the host by not sending random guest data to the host. But device isolation is not yet in place so kzalloc is not really needed. Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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