diff options
author | David Woodhouse <dwmw@amazon.co.uk> | 2023-10-20 19:15:27 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-11-28 20:19:57 +0300 |
commit | 192e6eba4e72655571907dddcbf2ad61a373cea7 (patch) | |
tree | 1f8dedaecad5b4947d1ccffd8933a935e4b9a768 /drivers/pci/pci-sysfs.c | |
parent | 202f4d78d16b5fa920f0d28c22ed2c07f189879a (diff) | |
download | linux-192e6eba4e72655571907dddcbf2ad61a373cea7.tar.xz |
hvc/xen: fix event channel handling for secondary consoles
commit ef5dd8ec88ac11e8e353164407d55b73c988b369 upstream.
The xencons_connect_backend() function allocates a local interdomain
event channel with xenbus_alloc_evtchn(), then calls
bind_interdomain_evtchn_to_irq_lateeoi() to bind to that port# on the
*remote* domain.
That doesn't work very well:
(qemu) device_add xen-console,id=con1,chardev=pty0
[ 44.323872] xenconsole console-1: 2 xenbus_dev_probe on device/console/1
[ 44.323995] xenconsole: probe of console-1 failed with error -2
Fix it to use bind_evtchn_to_irq_lateeoi(), which does the right thing
by just binding that *local* event channel to an irq. The backend will
do the interdomain binding.
This didn't affect the primary console because the setup for that is
special — the toolstack allocates the guest event channel and the guest
discovers it with HVMOP_get_param.
Fixes: fe415186b43d ("xen/console: harden hvc_xen against event channel storms")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20231020161529.355083-2-dwmw2@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/pci/pci-sysfs.c')
0 files changed, 0 insertions, 0 deletions