|
 |
9ae3a8 |
From dd0ab2d849f8a93fe54a29eedb8a536fbc42fe5d Mon Sep 17 00:00:00 2001
|
|
|
9ae3a8 |
From: Amit Shah <amit.shah@redhat.com>
|
|
|
9ae3a8 |
Date: Tue, 8 Oct 2013 06:13:07 +0200
|
|
|
9ae3a8 |
Subject: [PATCH 08/11] char: remove watch callback on chardev detach from frontend
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
RH-Author: Amit Shah <amit.shah@redhat.com>
|
|
|
9ae3a8 |
Message-id: <0044db8c12053fd38667200f350132d7a3485cde.1381210228.git.amit.shah@redhat.com>
|
|
|
9ae3a8 |
Patchwork-id: 54729
|
|
|
9ae3a8 |
O-Subject: [RHEL7 qemu-kvm PATCH 3/3] char: remove watch callback on chardev detach from frontend
|
|
|
9ae3a8 |
Bugzilla: 1007222
|
|
|
9ae3a8 |
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
|
9ae3a8 |
RH-Acked-by: Gerd Hoffmann <kraxel@redhat.com>
|
|
|
9ae3a8 |
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
If a frontend device releases the chardev (via unplug), the chr handlers
|
|
|
9ae3a8 |
are set to NULL via qdev's exit callbacks invoking
|
|
|
9ae3a8 |
qemu_chr_add_handlers(). If the chardev had a pending operation, a
|
|
|
9ae3a8 |
callback will be invoked, which will try to access data in the
|
|
|
9ae3a8 |
just-released frontend, causing a segfault.
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
Ensure the callbacks are disabled when frontends release chardevs.
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
This was seen when a virtio-serial port was unplugged when heavy
|
|
|
9ae3a8 |
guest->host IO was in progress (causing a callback to be registered).
|
|
|
9ae3a8 |
In the window in which the throttling was active, unplugging ports
|
|
|
9ae3a8 |
caused a qemu segfault.
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
https://bugzilla.redhat.com/show_bug.cgi?id=985205
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
CC: <qemu-stable@nongnu.org>
|
|
|
9ae3a8 |
Reported-by: Sibiao Luo <sluo@redhat.com>
|
|
|
9ae3a8 |
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
|
|
|
9ae3a8 |
Signed-off-by: Amit Shah <amit.shah@redhat.com>
|
|
|
9ae3a8 |
---
|
|
|
9ae3a8 |
qemu-char.c | 3 +++
|
|
|
9ae3a8 |
1 file changed, 3 insertions(+)
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
|
|
|
9ae3a8 |
---
|
|
|
9ae3a8 |
qemu-char.c | 3 +++
|
|
|
9ae3a8 |
1 files changed, 3 insertions(+), 0 deletions(-)
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
diff --git a/qemu-char.c b/qemu-char.c
|
|
|
9ae3a8 |
index 8d46f98..2fb876c 100644
|
|
|
9ae3a8 |
--- a/qemu-char.c
|
|
|
9ae3a8 |
+++ b/qemu-char.c
|
|
|
9ae3a8 |
@@ -195,6 +195,8 @@ void qemu_chr_fe_printf(CharDriverState *s, const char *fmt, ...)
|
|
|
9ae3a8 |
va_end(ap);
|
|
|
9ae3a8 |
}
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
+static void remove_fd_in_watch(CharDriverState *chr);
|
|
|
9ae3a8 |
+
|
|
|
9ae3a8 |
void qemu_chr_add_handlers(CharDriverState *s,
|
|
|
9ae3a8 |
IOCanReadHandler *fd_can_read,
|
|
|
9ae3a8 |
IOReadHandler *fd_read,
|
|
|
9ae3a8 |
@@ -205,6 +207,7 @@ void qemu_chr_add_handlers(CharDriverState *s,
|
|
|
9ae3a8 |
|
|
|
9ae3a8 |
if (!opaque && !fd_can_read && !fd_read && !fd_event) {
|
|
|
9ae3a8 |
fe_open = 0;
|
|
|
9ae3a8 |
+ remove_fd_in_watch(s);
|
|
|
9ae3a8 |
} else {
|
|
|
9ae3a8 |
fe_open = 1;
|
|
|
9ae3a8 |
}
|
|
|
9ae3a8 |
--
|
|
|
9ae3a8 |
1.7.1
|
|
|
9ae3a8 |
|