The patch titled
Subject: radix-tree: must check __radix_tree_preload() return value
has been added to the -mm tree. Its filename is
radix-tree-must-check-__radix_tree_preload-return-value.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/radix-tree-must-check-__radix_tree_preload-return-value.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/radix-tree-must-check-__radix_tree_preload-return-value.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
Subject: radix-tree: must check __radix_tree_preload() return value
__radix_tree_preload() only disables preemption if no error is returned.
So we really need to make sure callers always check the return value.
idr_preload() contract is to always disable preemption, so we need
to add a missing preempt_disable() if an error happened.
Similarly, ida_pre_get() only needs to call preempt_enable() in the
case no error happened.
Link: http://lkml.kernel.org/r/1504637190.15310.62.camel@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 0a835c4f090a ("Reimplement IDR and IDA using the radix tree")
Fixes: 7ad3d4d85c7a ("ida: Move ida_bitmap to a percpu variable")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [4.11+]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/radix-tree.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff -puN lib/radix-tree.c~radix-tree-must-check-__radix_tree_preload-return-value lib/radix-tree.c
--- a/lib/radix-tree.c~radix-tree-must-check-__radix_tree_preload-return-value
+++ a/lib/radix-tree.c
@@ -463,7 +463,7 @@ radix_tree_node_free(struct radix_tree_n
* To make use of this facility, the radix tree must be initialised without
* __GFP_DIRECT_RECLAIM being passed to INIT_RADIX_TREE().
*/
-static int __radix_tree_preload(gfp_t gfp_mask, unsigned nr)
+static __must_check int __radix_tree_preload(gfp_t gfp_mask, unsigned nr)
{
struct radix_tree_preload *rtp;
struct radix_tree_node *node;
@@ -2104,7 +2104,8 @@ EXPORT_SYMBOL(radix_tree_tagged);
*/
void idr_preload(gfp_t gfp_mask)
{
- __radix_tree_preload(gfp_mask, IDR_PRELOAD_SIZE);
+ if (__radix_tree_preload(gfp_mask, IDR_PRELOAD_SIZE))
+ preempt_disable();
}
EXPORT_SYMBOL(idr_preload);
@@ -2118,13 +2119,13 @@ EXPORT_SYMBOL(idr_preload);
*/
int ida_pre_get(struct ida *ida, gfp_t gfp)
{
- __radix_tree_preload(gfp, IDA_PRELOAD_SIZE);
/*
* The IDA API has no preload_end() equivalent. Instead,
* ida_get_new() can return -EAGAIN, prompting the caller
* to return to the ida_pre_get() step.
*/
- preempt_enable();
+ if (!__radix_tree_preload(gfp, IDA_PRELOAD_SIZE))
+ preempt_enable();
if (!this_cpu_read(ida_bitmap)) {
struct ida_bitmap *bitmap = kmalloc(sizeof(*bitmap), gfp);
_
Patches currently in -mm which might be from edumazet@xxxxxxxxxx are
radix-tree-must-check-__radix_tree_preload-return-value.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
