From 9ac625a3986034d79938baf9604210280fae35fa Mon Sep 17 00:00:00 2001
From: Jeff Dike <jdike@addtoit.com>
Date: Wed, 14 Nov 2007 17:00:23 -0800
Subject: [PATCH] uml: fix spurious IRQ testing
The spurious IRQ testing in request_irq is mishandled in um_request_irq, which
sets the incoming file descriptors non-blocking only after request_irq
succeeds. This results in the spurious irq calling read on a blocking
descriptor, and a hang.
Fixed by reversing the O_NONBLOCK setting and the request_irq call.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/um/kernel/irq.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 70c2d625b070..ba11ccd6a8a3 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -347,14 +347,15 @@ int um_request_irq(unsigned int irq, int fd, int type,
{
int err;
- err = request_irq(irq, handler, irqflags, devname, dev_id);
- if (err)
- return err;
-
- if (fd != -1)
+ if (fd != -1) {
err = activate_fd(irq, fd, type, dev_id);
- return err;
+ if (err)
+ return err;
+ }
+
+ return request_irq(irq, handler, irqflags, devname, dev_id);
}
+
EXPORT_SYMBOL(um_request_irq);
EXPORT_SYMBOL(reactivate_fd);
--
2.20.1