[PATCH 6/47] sysfs: Make poll behaviour consistent

From: =?utf-8?q?Juha_Yrj=F6l=E4?= <juha.yrjola@xxxxxxxxxxxxx>

When no events have been reported by sysfs_notify(), sd->s_events
was previously set to zero. The initial value for new readers is
also zero, so poll was blocking, regardless of whether the attribute
was read by the process or not.

Make poll behave consistently by setting the initial value of
sd->s_events to non-zero.

Signed-off-by: Juha Yrjola <juha.yrjola@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
fs/sysfs/dir.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 61c4243..5f3d725 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -43,7 +43,7 @@ static struct sysfs_dirent * sysfs_new_d

memset(sd, 0, sizeof(*sd));
atomic_set(&sd->s_count, 1);
- atomic_set(&sd->s_event, 0);
+ atomic_set(&sd->s_event, 1);
INIT_LIST_HEAD(&sd->s_children);
list_add(&sd->s_sibling, &parent_sd->s_children);
sd->s_element = element;
--
1.4.2.1

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