From: Greg Kroah-Hartman Date: Tue, 19 Nov 2019 04:59:03 +0000 (+0100) Subject: 4.4-stable patches X-Git-Tag: v5.3.12~19 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=77e23f826755c7a5f21749e38a12b647fd835dcb;p=thirdparty%2Fkernel%2Fstable-queue.git 4.4-stable patches added patches: memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch --- diff --git a/queue-4.4/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch b/queue-4.4/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch new file mode 100644 index 00000000000..36071321f0d --- /dev/null +++ b/queue-4.4/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch @@ -0,0 +1,38 @@ +From zhongjiang@huawei.com Tue Nov 19 05:57:26 2019 +From: zhong jiang +Date: Mon, 18 Nov 2019 11:26:09 +0800 +Subject: memfd: Use radix_tree_deref_slot_protected to avoid the warning. +To: , , , +Cc: , +Message-ID: <20191118032610.182862-3-zhongjiang@huawei.com> + +From: zhong jiang + +The commit eb4058d8daf8 ("memfd: Fix locking when tagging pins") +introduces the following warning messages. + +*WARNING: suspicious RCU usage in memfd_wait_for_pins* + +It is because we still use radix_tree_deref_slot without read_rcu_lock. +We should use radix_tree_deref_slot_protected instead in the case. + +Cc: stable@vger.kernel.org +Fixes: eb4058d8daf8 ("memfd: Fix locking when tagging pins") +Signed-off-by: zhong jiang +Reviewed-by: Matthew Wilcox (Oracle) +Signed-off-by: Greg Kroah-Hartman +--- + mm/shmem.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/mm/shmem.c ++++ b/mm/shmem.c +@@ -1862,7 +1862,7 @@ static void shmem_tag_pins(struct addres + spin_lock_irq(&mapping->tree_lock); + restart: + radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { +- page = radix_tree_deref_slot(slot); ++ page = radix_tree_deref_slot_protected(slot, &mapping->tree_lock); + if (!page || radix_tree_exception(page)) { + if (radix_tree_deref_retry(page)) + goto restart; diff --git a/queue-4.4/series b/queue-4.4/series index 4344fd55faa..5d7764d36eb 100644 --- a/queue-4.4/series +++ b/queue-4.4/series @@ -96,3 +96,4 @@ arm64-dts-amd-fix-spi-bus-warnings.patch fuse-use-read_once-on-congestion_threshold-and-max_b.patch bluetooth-hci_ldisc-fix-null-pointer-derefence-in-case-of-early-data.patch bluetooth-hci_ldisc-postpone-hci_uart_proto_ready-bit-set-in-hci_uart_set_proto.patch +memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch