[PATCH 4.19 253/338] um: Fix uml_mconsole stop/go

Greg Kroah-Hartman
2022-04-14T14:04:41Z

From: Anton Ivanov <anton.ivanov@cambridgegreys.com>

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>
---
arch/um/drivers/mconsole_kern.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- 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 *re
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);