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>
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 70c2d62..ba11ccd 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -347,14 +347,15 @@
{
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);