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>
I dived into lguest again, reworking the pagetable code so we can move
the switcher page: our fixmaps sometimes take more than 2MB now...
Cheers,
Rusty.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=1tYL
-----END PGP SIGNATURE-----
Merge tag 'virtio-next-for-linus' of 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
...
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>
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>
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
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
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>
This reverts commit 8078db789a, 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>
Cheers,
Rusty.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)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=KcDx
-----END PGP SIGNATURE-----
Merge tag 'virtio-next-for-linus' of 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.
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>
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>
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>
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>
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.
You can see my solution in my pending-rebases branch, if that helps, but I
know you love merging:
https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe
Cheers,
Rusty.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)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=myDR
-----END PGP SIGNATURE-----
Merge tag 'virtio-next-for-linus' of 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.
...
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>
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>
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)
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>
Free the allocated scatter list if send_pages fails in function
port_splice_write.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If register_virtio_driver() fails, virtio-ports class is not destroyed.
The patch adds error handling of register_virtio_driver().
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Allocate scatterlist according to the current pipe size.
This allows splicing bigger buffer if the pipe size has
been changed by fcntl.
Changes in v2:
- Just a minor fix for avoiding a confliction with previous patch.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Wait if the port is not connected or full on splice
like as write is doing.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add a failback memcpy path for unstealable pipe buffer.
If buf->ops->steal() fails, virtio-serial tries to
copy the page contents to an allocated page, instead
of just failing splice().
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Enable to use splice_write from pipe to virtio-console port.
This steals pages from pipe and directly send it to host.
Note that this may accelerate only the guest to host path.
Changes in v2:
- Use GFP_KERNEL instead of GFP_ATOMIC in syscall context function.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a port was open before going into one of the sleep states, the port
can continue normal operation after restore. However, the host has to
be told that the guest side of the connection is open to restore
pre-suspend state.
This wasn't noticed so far due to a bug in qemu that was fixed recently
(which marked the guest-side connection as always open).
CC: stable@vger.kernel.org # Only for 3.3
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Many users of debugfs copy the implementation of default_open() when
they want to support a custom read/write function op. This leads to a
proliferation of the default_open() implementation across the entire
tree.
Now that the common implementation has been consolidated into libfs we
can replace all the users of this function with simple_open().
This replacement was done with the following semantic patch:
<smpl>
@ open @
identifier open_f != simple_open;
identifier i, f;
@@
-int open_f(struct inode *i, struct file *f)
-{
(
-if (i->i_private)
-f->private_data = i->i_private;
|
-f->private_data = i->i_private;
)
-return 0;
-}
@ has_open depends on open @
identifier fops;
identifier open.open_f;
@@
struct file_operations fops = {
...
-.open = open_f,
+.open = simple_open,
...
};
</smpl>
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To ensure we don't receive any more interrupts from the host after we
enter the freeze function, disable all vq interrupts.
There wasn't any problem seen due to this in tests, but applying this
patch makes the freeze case more robust.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Remove all vqs and associated buffers in the freeze callback which
prepares us to go into hibernation state. On restore, re-create all the
vqs and populate the input vqs with buffers to get to the pre-hibernate
state.
Note: Any outstanding unconsumed buffers are discarded; which means
there's a possibility of data loss in case the host or the guest didn't
consume any data already present in the vqs. This can be addressed in a
later patch series, perhaps in virtio common code.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This common code will be shared with the PM freeze function.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Remove wrapper functions. This makes the allocation type explicit in
all callers; I used GPF_KERNEL where it seemed obvious, left it at
GFP_ATOMIC otherwise.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
On s390 I have seen some random
"Warning: unable to open an initial console"
boot failure. Turns out that tty_open fails, because the
hvc_alloc was not yet done. In former times this could not happen,
since the probe function automatically called hvc_alloc. With newer
versions (multiport) some host<->guest interaction is required
before hvc_alloc is called. This might be too late, especially if
an initramfs is involved. Lets use a completion if we have
multiport and an early console.
[Amit:
* Use NULL instead of 0 for pointer comparison
* Rename 'port_added' to 'early_console_added'
* Re-format, re-word commit message
* Rebase patch on top of current queue]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Acked-by: Chrstian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit adds port-specific stats for the number of bytes received,
sent and discarded. They're exposed via the debugfs interface. This
data can be used to check for data loss bugs (or disprove such claims).
It can also be used for accounting, if there's such a need.
The stats remain valid throughout the lifetime of the port. Unplugging
a port will reset the stats. The numbers are not reset across port
opens/closes.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
discard_port_data() used virtqueue_get_buf() directly instead of using
get_inbuf(). Fix this, so that we get accounting for all received
bytes. This also simplifies the code a lot.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of pulling in a buffer from the vq each time it's called,
get_inbuf() now checks if the current active buffer, in port->inbuf is
valid. If it is, just returns a pointer to it. This ends up
simplifying a lot of code calling get_inbuf() since the check for
port->inbuf being valid was done by all the callers.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
get_inbuf() returns void *. There's no reason to return void pointers
instead of the correct struct port_buffer *.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Get ready to support suspend/resume by using the freezable calls so that
blocking read/write syscalls are handled properly across suspend/resume.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't allow port name changes dynamically for a port. So any
requests by the host to change the name are ignored.
Before this patch, if the hypervisor sent a port name while we had one
set already, we would leak memory equivalent to the size of the old
name.
This scenario wasn't expected so far, but with the suspend-resume
support, we'll send the VIRTIO_CONSOLE_PORT_READY message after restore,
which can get us into this situation.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Convert spaces to tabs and fix indentation for an if statement split
into multiple lines.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch modifies virtio-console to use virtio_config_val() instead
of a 'if(virtio_has_feature()) vdev->config->get()' construct to retrieve
optional values from the config space.
Cc: Amit Shah <amit.shah@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
A pending cleanup will mean that module.h won't be implicitly
everywhere anymore. Make sure the modular drivers in char are
actually calling out for <module.h> explicitly in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
That's already been done by the virtio infrastructure before the probe
function is called.
Reported-by: alexey.kardashevskiy@au1.ibm.com
Acked-by: Amit Shah <amit.shah@redhat.com>
Tested-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This call was disabled as hot-unplugging one virtconsole port led to
another virtconsole port freezing.
Upon testing it again, this now works, so enable it.
In addition, a bug was found in qemu wherein removing a port of one type
caused the guest output from another port to stop working. I doubt it
was just this bug that caused it (since disabling the hvc_remove() call
did allow other ports to continue working), but since it's all solved
now, we're fine with hot-unplugging of virtconsole ports.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a virtio-console device gets unplugged while a port is open, a
subsequent close() call on the port accesses vqs to free up buffers.
This can lead to a crash.
The buffers are already freed up as a result of the call to
unplug_ports() from virtcons_remove(). The fix is to simply not access
vq information if port->portdev is NULL.
Reported-by: juzhang <juzhang@redhat.com>
CC: stable@kernel.org
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yoshihiro YUNOMAE