Following commit caused the build failures on s390,
On Mon, 27 Sept 2021 at 22:43, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> From: Alexandra Winter <wintera@xxxxxxxxxxxxx>
>
> [ Upstream commit d2b59bd4b06d84a4eadb520b0f71c62fe8ec0a62 ]
>
> Commit 0b9902c1fcc5 ("s390/qeth: fix deadlock during recovery") removed
> taking discipline_mutex inside qeth_do_reset(), fixing potential
> deadlocks. An error path was missed though, that still takes
> discipline_mutex and thus has the original deadlock potential.
>
> Intermittent deadlocks were seen when a qeth channel path is configured
> offline, causing a race between qeth_do_reset and ccwgroup_remove.
> Call qeth_set_offline() directly in the qeth_do_reset() error case and
> then a new variant of ccwgroup_set_offline(), without taking
> discipline_mutex.
>
> Fixes: b41b554c1ee7 ("s390/qeth: fix locking for discipline setup / removal")
> Signed-off-by: Alexandra Winter <wintera@xxxxxxxxxxxxx>
> Reviewed-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
> Signed-off-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> arch/s390/include/asm/ccwgroup.h | 2 +-
> drivers/s390/cio/ccwgroup.c | 10 ++++++++--
> drivers/s390/net/qeth_core_main.c | 3 ++-
> 3 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/arch/s390/include/asm/ccwgroup.h b/arch/s390/include/asm/ccwgroup.h
> index ad3acb1e882b..8a22da9a735a 100644
> --- a/arch/s390/include/asm/ccwgroup.h
> +++ b/arch/s390/include/asm/ccwgroup.h
> @@ -58,7 +58,7 @@ struct ccwgroup_device *get_ccwgroupdev_by_busid(struct ccwgroup_driver *gdrv,
> char *bus_id);
>
> extern int ccwgroup_set_online(struct ccwgroup_device *gdev);
> -extern int ccwgroup_set_offline(struct ccwgroup_device *gdev);
> +int ccwgroup_set_offline(struct ccwgroup_device *gdev, bool call_gdrv);
>
> extern int ccwgroup_probe_ccwdev(struct ccw_device *cdev);
> extern void ccwgroup_remove_ccwdev(struct ccw_device *cdev);
> diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
> index 483a9ecfcbb1..cfdc1c7825d0 100644
> --- a/drivers/s390/cio/ccwgroup.c
> +++ b/drivers/s390/cio/ccwgroup.c
> @@ -98,12 +98,13 @@ EXPORT_SYMBOL(ccwgroup_set_online);
> /**
> * ccwgroup_set_offline() - disable a ccwgroup device
> * @gdev: target ccwgroup device
> + * @call_gdrv: Call the registered gdrv set_offline function
> *
> * This function attempts to put the ccwgroup device into the offline state.
> * Returns:
> * %0 on success and a negative error value on failure.
> */
> -int ccwgroup_set_offline(struct ccwgroup_device *gdev)
> +int ccwgroup_set_offline(struct ccwgroup_device *gdev, bool call_gdrv)
> {
> struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
> int ret = -EINVAL;
> @@ -112,11 +113,16 @@ int ccwgroup_set_offline(struct ccwgroup_device *gdev)
> return -EAGAIN;
> if (gdev->state == CCWGROUP_OFFLINE)
> goto out;
> + if (!call_gdrv) {
> + ret = 0;
> + goto offline;
> + }
> if (gdrv->set_offline)
> ret = gdrv->set_offline(gdev);
> if (ret)
> goto out;
>
> +offline:
> gdev->state = CCWGROUP_OFFLINE;
> out:
> atomic_set(&gdev->onoff, 0);
> @@ -145,7 +151,7 @@ static ssize_t ccwgroup_online_store(struct device *dev,
> if (value == 1)
> ret = ccwgroup_set_online(gdev);
> else if (value == 0)
> - ret = ccwgroup_set_offline(gdev);
> + ret = ccwgroup_set_offline(gdev, true);
> else
> ret = -EINVAL;
> out:
> diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
> index 7b0155b0e99e..15477bfb5bd8 100644
> --- a/drivers/s390/net/qeth_core_main.c
> +++ b/drivers/s390/net/qeth_core_main.c
> @@ -5406,7 +5406,8 @@ static int qeth_do_reset(void *data)
> dev_info(&card->gdev->dev,
> "Device successfully recovered!\n");
> } else {
> - ccwgroup_set_offline(card->gdev);
> + qeth_set_offline(card, disc, true);
> + ccwgroup_set_offline(card->gdev, false);
drivers/s390/net/qeth_core_main.c: In function 'qeth_close_dev_handler':
drivers/s390/net/qeth_core_main.c:83:9: error: too few arguments to
function 'ccwgroup_set_offline'
83 | ccwgroup_set_offline(card->gdev);
| ^~~~~~~~~~~~~~~~~~~~
In file included from drivers/s390/net/qeth_core.h:44,
from drivers/s390/net/qeth_core_main.c:46:
arch/s390/include/asm/ccwgroup.h:61:5: note: declared here
61 | int ccwgroup_set_offline(struct ccwgroup_device *gdev, bool call_gdrv);
| ^~~~~~~~~~~~~~~~~~~~
make[3]: *** [scripts/Makefile.build:280:
drivers/s390/net/qeth_core_main.o] Error 1
Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Build url:
https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc/-/jobs/1626658768#L73
--
Linaro LKFT
https://lkft.linaro.org
