diff options
| author | Amit Shah <amit.shah@redhat.com> | 2013-08-28 15:24:05 +0530 |
|---|---|---|
| committer | Amit Shah <amit.shah@redhat.com> | 2013-09-05 18:30:36 +0530 |
| commit | 386a5a1e0057e220f79c48fe3689e3dfb17f1b09 (patch) | |
| tree | c65829a5be0be6978005dc0047ffbbc0533f7497 /qemu-char.c | |
| parent | 26da70c72524eb22c946ab19ec98a217b8252f7e (diff) | |
char: remove watch callback on chardev detach from frontend
If a frontend device releases the chardev (via unplug), the chr handlers
are set to NULL via qdev's exit callbacks invoking
qemu_chr_add_handlers(). If the chardev had a pending operation, a
callback will be invoked, which will try to access data in the
just-released frontend, causing a segfault.
Ensure the callbacks are disabled when frontends release chardevs.
This was seen when a virtio-serial port was unplugged when heavy
guest->host IO was in progress (causing a callback to be registered).
In the window in which the throttling was active, unplugging ports
caused a qemu segfault.
https://bugzilla.redhat.com/show_bug.cgi?id=985205
CC: <qemu-stable@nongnu.org>
Reported-by: Sibiao Luo <sluo@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Diffstat (limited to 'qemu-char.c')
| -rw-r--r-- | qemu-char.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/qemu-char.c b/qemu-char.c index 0a0833f77b..6f111abfbe 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -193,6 +193,8 @@ void qemu_chr_fe_printf(CharDriverState *s, const char *fmt, ...) va_end(ap); } +static void remove_fd_in_watch(CharDriverState *chr); + void qemu_chr_add_handlers(CharDriverState *s, IOCanReadHandler *fd_can_read, IOReadHandler *fd_read, @@ -203,6 +205,7 @@ void qemu_chr_add_handlers(CharDriverState *s, if (!opaque && !fd_can_read && !fd_read && !fd_event) { fe_open = 0; + remove_fd_in_watch(s); } else { fe_open = 1; } |