2008-01-17 21:46:46

by Jeff Dike

[permalink] [raw]
Subject: [PATCH 15/20] UML - Fix infinite mconsole loop

From: Karol Swietlicki <[email protected]>

This patch takes care of a problem with the stopping code.

The function inside the while condition returns 0 to signify a problem.
A problem could be for example a bad command or a bad version of the
mconsole client.
A bad command would terminate the stopping loop and resume the kernel.
This is a problem.

A better solution is to make the loop infinite and don't leave it
until we are explicitly told to.

Signed-off-by: Karol Swietlicki <[email protected]>
Signed-off-by: Jeff Dike <[email protected]>
---
arch/um/drivers/mconsole_kern.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

Index: linux-2.6.22/arch/um/drivers/mconsole_kern.c
===================================================================
--- linux-2.6.22.orig/arch/um/drivers/mconsole_kern.c 2007-12-12 13:44:20.000000000 -0500
+++ linux-2.6.22/arch/um/drivers/mconsole_kern.c 2007-12-12 15:53:08.000000000 -0500
@@ -305,7 +305,9 @@ void mconsole_stop(struct mc_request *re
deactivate_fd(req->originating_fd, MCONSOLE_IRQ);
os_set_fd_block(req->originating_fd, 1);
mconsole_reply(req, "stopped", 0, 0);
- while (mconsole_get_request(req->originating_fd, req)) {
+ for (;;) {
+ if (!mconsole_get_request(req->originating_fd, req))
+ continue;
if (req->cmd->handler == mconsole_go)
break;
if (req->cmd->handler == mconsole_stop) {