6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: NeilBrown <neilb@xxxxxxx>
[ Upstream commit e8ae8ad479e2d037daa33756e5e72850a7bd37a9 ]
The comment for idr_for_each_entry_ul() states
after normal termination @entry is left with the value NULL
This is not correct in the case where UINT_MAX has an entry in the idr.
In that case @entry will be non-NULL after termination.
No current code depends on the documentation being correct, but to
save future code we should fix it.
Also fix idr_for_each_entry_continue_ul(). While this is not documented
as leaving @entry as NULL, the mellanox driver appears to depend on
it doing so. So make that explicit in the documentation as well as in
the code.
Fixes: e33d2b74d805 ("idr: fix overflow case for idr_for_each_entry_ul()")
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Chris Mi <chrism@xxxxxxxxxxxx>
Cc: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Signed-off-by: NeilBrown <neilb@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/linux/idr.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/include/linux/idr.h b/include/linux/idr.h
index a0dce14090a9e..da5f5fa4a3a6a 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -200,7 +200,7 @@ static inline void idr_preload_end(void)
*/
#define idr_for_each_entry_ul(idr, entry, tmp, id) \
for (tmp = 0, id = 0; \
- tmp <= id && ((entry) = idr_get_next_ul(idr, &(id))) != NULL; \
+ ((entry) = tmp <= id ? idr_get_next_ul(idr, &(id)) : NULL) != NULL; \
tmp = id, ++id)
/**
@@ -224,10 +224,12 @@ static inline void idr_preload_end(void)
* @id: Entry ID.
*
* Continue to iterate over entries, continuing after the current position.
+ * After normal termination @entry is left with the value NULL. This
+ * is convenient for a "not found" value.
*/
#define idr_for_each_entry_continue_ul(idr, entry, tmp, id) \
for (tmp = id; \
- tmp <= id && ((entry) = idr_get_next_ul(idr, &(id))) != NULL; \
+ ((entry) = tmp <= id ? idr_get_next_ul(idr, &(id)) : NULL) != NULL; \
tmp = id, ++id)
/*
--
2.42.0
