+++ /dev/null
-From 936529dd0dc33682c44260c24b139ae51a0653cf Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Thu, 8 Apr 2021 15:18:39 +0800
-Subject: crypto: omap-aes - Fix PM reference leak on omap-aes.c
-
-From: Shixin Liu <liushixin2@huawei.com>
-
-[ Upstream commit 1f34cc4a8da34fbb250efb928f9b8c6fe7ee0642 ]
-
-pm_runtime_get_sync will increment pm usage counter even it failed.
-Forgetting to putting operation will result in reference leak here.
-Fix it by replacing it with pm_runtime_resume_and_get to keep usage
-counter balanced.
-
-Signed-off-by: Shixin Liu <liushixin2@huawei.com>
-Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- drivers/crypto/omap-aes.c | 6 +++---
- 1 file changed, 3 insertions(+), 3 deletions(-)
-
-diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c
-index a5d6e1a0192b..2288fa6a939e 100644
---- a/drivers/crypto/omap-aes.c
-+++ b/drivers/crypto/omap-aes.c
-@@ -107,7 +107,7 @@ static int omap_aes_hw_init(struct omap_aes_dev *dd)
- dd->err = 0;
- }
-
-- err = pm_runtime_get_sync(dd->dev);
-+ err = pm_runtime_resume_and_get(dd->dev);
- if (err < 0) {
- dev_err(dd->dev, "failed to get sync: %d\n", err);
- return err;
-@@ -1159,7 +1159,7 @@ static int omap_aes_probe(struct platform_device *pdev)
- pm_runtime_set_autosuspend_delay(dev, DEFAULT_AUTOSUSPEND_DELAY);
-
- pm_runtime_enable(dev);
-- err = pm_runtime_get_sync(dev);
-+ err = pm_runtime_resume_and_get(dev);
- if (err < 0) {
- dev_err(dev, "%s: failed to get_sync(%d)\n",
- __func__, err);
-@@ -1327,7 +1327,7 @@ static int omap_aes_suspend(struct device *dev)
-
- static int omap_aes_resume(struct device *dev)
- {
-- pm_runtime_get_sync(dev);
-+ pm_runtime_resume_and_get(dev);
- return 0;
- }
- #endif
---
-2.30.2
-
For more detail, please refer with Christoph's "split mddev_find" patch
in later commits.
-*** env ***
-kvm-qemu VM 2C1G with 2 iscsi luns
-kernel should be non-preempt
-
-*** script ***
-
-about trigger every time with below script
-
-```
-1 node1="mdcluster1"
-2 node2="mdcluster2"
-3
-4 mdadm -Ss
-5 ssh ${node2} "mdadm -Ss"
-6 wipefs -a /dev/sda /dev/sdb
-7 mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
- /dev/sdb --assume-clean
-8
-9 for i in {1..10}; do
-10 echo ==== $i ====;
-11
-12 echo "test ...."
-13 ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
-14 sleep 1
-15
-16 echo "clean ....."
-17 ssh ${node2} "mdadm -Ss"
-18 done
-```
-
-I use mdcluster env to trigger soft lockup, but it isn't mdcluster
-speical bug. To stop md array in mdcluster env will do more jobs than
-non-cluster array, which will leave enough time/gap to allow kernel to
-run md_open.
-
-*** stack ***
-
-```
-[ 884.226509] mddev_put+0x1c/0xe0 [md_mod]
-[ 884.226515] md_open+0x3c/0xe0 [md_mod]
-[ 884.226518] __blkdev_get+0x30d/0x710
-[ 884.226520] ? bd_acquire+0xd0/0xd0
-[ 884.226522] blkdev_get+0x14/0x30
-[ 884.226524] do_dentry_open+0x204/0x3a0
-[ 884.226531] path_openat+0x2fc/0x1520
-[ 884.226534] ? seq_printf+0x4e/0x70
-[ 884.226536] do_filp_open+0x9b/0x110
-[ 884.226542] ? md_release+0x20/0x20 [md_mod]
-[ 884.226543] ? seq_read+0x1d8/0x3e0
-[ 884.226545] ? kmem_cache_alloc+0x18a/0x270
-[ 884.226547] ? do_sys_open+0x1bd/0x260
-[ 884.226548] do_sys_open+0x1bd/0x260
-[ 884.226551] do_syscall_64+0x5b/0x1e0
-[ 884.226554] entry_SYSCALL_64_after_hwframe+0x44/0xa9
-```
-
-*** rootcause ***
-
-"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
---monitor" by default. When "mdadm -Ss" is running, the stop action will
-wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
-info from /proc/mdstat. This time mddev in kernel still exist, so
-/proc/mdstat still show md device, which makes "mdadm --monitor" to open
-/dev/md0.
-
-The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
-open action will trigger md_open which is creating action. Racing is
-happening.
-
-```
-<thread 1>: "mdadm -Ss"
-md_release
- mddev_put deletes mddev from all_mddevs
- queue_work for mddev_delayed_delete
- at this time, "/dev/md0" is still available for opening
-
-<thread 2>: "mdadm --monitor ..."
-md_open
- + mddev_find can't find mddev of /dev/md0, and create a new mddev and
- | return.
- + trigger "if (mddev->gendisk != bdev->bd_disk)" and return
- -ERESTARTSYS.
-```
-
-In non-preempt kernel, <thread 2> is occupying on current CPU. and
-mddev_delayed_delete which was created in <thread 1> also can't be
-schedule.
-
-In preempt kernel, it can also trigger above racing. But kernel doesn't
-allow one thread running on a CPU all the time. after <thread 2> running
-some time, the later "mdadm -A" (refer above script line 13) will call
-md_alloc to alloc a new gendisk for mddev. it will break md_open
-statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
-the soft lockup is broken.
-
-Cc: stable@vger.kernel.org
-Reviewed-by: Christoph Hellwig <hch@lst.de>
-Signed-off-by: Zhao Heming <heming.zhao@suse.com>
-Signed-off-by: Song Liu <song@kernel.org>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
- drivers/md/md.c | 3 +--
+ drivers/md/md.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
-diff --git a/drivers/md/md.c b/drivers/md/md.c
-index 368cad6cd53a..464cca5d5952 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
-@@ -7821,8 +7821,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
+@@ -7481,8 +7481,7 @@ static int md_open(struct block_device *
/* Wait until bdev->bd_disk is definitely gone */
if (work_pending(&mddev->del_work))
flush_workqueue(md_misc_wq);
}
BUG_ON(mddev != bdev->bd_disk->private_data);
---
-2.31.1
-
projects / thirdparty / kernel / stable-queue.git / commitdiff
