From: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Date: Tue, 22 Feb 2022 12:44:10 +0000 (+0000)
Subject: um: Fix uml_mconsole stop/go
X-Git-Tag: v4.19.238~86
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c80ecb143a709ee8099e71f0db0b431820b35343;p=thirdparty%2Fkernel%2Fstable.git

um: Fix uml_mconsole stop/go

commit 1a3a6a2a035bb6c3a7ef4c788d8fd69a7b2d6284 upstream.

Moving to an EPOLL based IRQ controller broke uml_mconsole stop/go
commands. This fixes it and restores stop/go functionality.

Fixes: ff6a17989c08 ("Epoll based IRQ controller")
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index d5f9a2d1da1ba..ef4b00b9590b1 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -218,7 +218,7 @@ void mconsole_go(struct mc_request *req)
 
 void mconsole_stop(struct mc_request *req)
 {
-	deactivate_fd(req->originating_fd, MCONSOLE_IRQ);
+	block_signals();
 	os_set_fd_block(req->originating_fd, 1);
 	mconsole_reply(req, "stopped", 0, 0);
 	for (;;) {
@@ -242,6 +242,7 @@ void mconsole_stop(struct mc_request *req)
 	os_set_fd_block(req->originating_fd, 0);
 	reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
 	mconsole_reply(req, "", 0, 0);
+	unblock_signals();
 }
 
 static DEFINE_SPINLOCK(mc_devices_lock);