From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-f41.google.com (mail-ej1-f41.google.com [209.85.218.41]) by mail19.linbit.com (LINBIT Mail Daemon) with ESMTP id EC8F8422117 for ; Fri, 13 Jan 2023 13:35:48 +0100 (CET) Received: by mail-ej1-f41.google.com with SMTP id qk9so52025534ejc.3 for ; Fri, 13 Jan 2023 04:35:48 -0800 (PST) From: =?UTF-8?q?Christoph=20B=C3=B6hmwalder?= To: Jens Axboe Date: Fri, 13 Jan 2023 13:35:37 +0100 Message-Id: <20230113123538.144276-8-christoph.boehmwalder@linbit.com> In-Reply-To: <20230113123538.144276-1-christoph.boehmwalder@linbit.com> References: <20230113123538.144276-1-christoph.boehmwalder@linbit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Philipp Reisner , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Lars Ellenberg , drbd-dev@lists.linbit.com Subject: [Drbd-dev] [PATCH 7/8] drbd: interval tree: make removing an "empty" interval a no-op List-Id: "*Coordination* of development, patches, contributions -- *Questions* \(even to developers\) go to drbd-user, please." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Lars Ellenberg Trying to remove an "empty" (just initialized, or "cleared") interval from the tree, this results in an endless loop. As we typically protect the tree with a spinlock_irq, the result is a hung system. Be nice to error cleanup code paths, ignore removal of empty intervals. Signed-off-by: Lars Ellenberg Signed-off-by: Christoph Böhmwalder --- drivers/block/drbd/drbd_interval.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/block/drbd/drbd_interval.c b/drivers/block/drbd/drbd_interval.c index 5024ffd6143d..b6aaf0d4d85b 100644 --- a/drivers/block/drbd/drbd_interval.c +++ b/drivers/block/drbd/drbd_interval.c @@ -95,6 +95,10 @@ drbd_contains_interval(struct rb_root *root, sector_t sector, void drbd_remove_interval(struct rb_root *root, struct drbd_interval *this) { + /* avoid endless loop */ + if (drbd_interval_empty(this)) + return; + rb_erase_augmented(&this->rb, root, &augment_callbacks); } -- 2.38.1