kernel/linux.git/drivers/s390, branch v4.14.286

s390/lcs: fix variable dereferenced before check

2022-05-18T07:18:06+00:00

[ Upstream commit 671bb35c8e746439f0ed70815968f9a4f20a8deb ] smatch complains about drivers/s390/net/lcs.c:1741 lcs_get_control() warn: variable dereferenced before check 'card->dev' (see line 1739) Fixes: 27eb5ac8f015 ("[PATCH] s390: lcs driver bug fixes and improvements [1/2]") Signed-off-by: Alexandra Winter Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

s390/ctcm: fix potential memory leak

2022-05-18T07:18:06+00:00

[ Upstream commit 0c0b20587b9f25a2ad14db7f80ebe49bdf29920a ] smatch complains about drivers/s390/net/ctcm_mpc.c:1210 ctcmpc_unpack_skb() warn: possible memory leak of 'mpcginfo' mpc_action_discontact() did not free mpcginfo. Consolidate the freeing in ctcmpc_unpack_skb(). Fixes: 293d984f0e36 ("ctcm: infrastructure for replaced ctc driver") Signed-off-by: Alexandra Winter Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

s390/ctcm: fix variable dereferenced before check

2022-05-18T07:18:06+00:00

[ Upstream commit 2c50c6867c85afee6f2b3bcbc50fc9d0083d1343 ] Found by cppcheck and smatch. smatch complains about drivers/s390/net/ctcm_sysfs.c:43 ctcm_buffer_write() warn: variable dereferenced before check 'priv' (see line 42) Fixes: 3c09e2647b5e ("ctcm: rename READ/WRITE defines to avoid redefinitions") Reported-by: Colin Ian King Signed-off-by: Alexandra Winter Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

scsi: zfcp: Fix failed recovery on gone remote port with non-NPIV FCP devices

2022-02-08T17:16:24+00:00

commit 8c9db6679be4348b8aae108e11d4be2f83976e30 upstream. Suppose we have an environment with a number of non-NPIV FCP devices (virtual HBAs / FCP devices / zfcp "adapter"s) sharing the same physical FCP channel (HBA port) and its I_T nexus. Plus a number of storage target ports zoned to such shared channel. Now one target port logs out of the fabric causing an RSCN. Zfcp reacts with an ADISC ELS and subsequent port recovery depending on the ADISC result. This happens on all such FCP devices (in different Linux images) concurrently as they all receive a copy of this RSCN. In the following we look at one of those FCP devices. Requests other than FSF_QTCB_FCP_CMND can be slow until they get a response. Depending on which requests are affected by slow responses, there are different recovery outcomes. Here we want to fix failed recoveries on port or adapter level by avoiding recovery requests that can be slow. We need the cached N_Port_ID for the remote port "link" test with ADISC. Just before sending the ADISC, we now intentionally forget the old cached N_Port_ID. The idea is that on receiving an RSCN for a port, we have to assume that any cached information about this port is stale. This forces a fresh new GID_PN [FC-GS] nameserver lookup on any subsequent recovery for the same port. Since we typically can still communicate with the nameserver efficiently, we now reach steady state quicker: Either the nameserver still does not know about the port so we stop recovery, or the nameserver already knows the port potentially with a new N_Port_ID and we can successfully and quickly perform open port recovery. For the one case, where ADISC returns successfully, we re-initialize port->d_id because that case does not involve any port recovery. This also solves a problem if the storage WWPN quickly logs into the fabric again but with a different N_Port_ID. Such as on virtual WWPN takeover during target NPIV failover. [https://www.redbooks.ibm.com/abstracts/redp5477.html] In that case the RSCN from the storage FDISC was ignored by zfcp and we could not successfully recover the failover. On some later failback on the storage, we could have been lucky if the virtual WWPN got the same old N_Port_ID from the SAN switch as we still had cached. Then the related RSCN triggered a successful port reopen recovery. However, there is no guarantee to get the same N_Port_ID on NPIV FDISC. Even though NPIV-enabled FCP devices are not affected by this problem, this code change optimizes recovery time for gone remote ports as a side effect. The timely drop of cached N_Port_IDs prevents unnecessary slow open port attempts. While the problem might have been in code before v2.6.32 commit 799b76d09aee ("[SCSI] zfcp: Decouple gid_pn requests from erp") this fix depends on the gid_pn_work introduced with that commit, so we mark it as culprit to satisfy fix dependencies. Note: Point-to-point remote port is already handled separately and gets its N_Port_ID from the cached peer_d_id. So resetting port->d_id in general does not affect PtP. Link: https://lore.kernel.org/r/20220118165803.3667947-1-maier@linux.ibm.com Fixes: 799b76d09aee ("[SCSI] zfcp: Decouple gid_pn requests from erp") Cc: #2.6.32+ Suggested-by: Benjamin Block Reviewed-by: Benjamin Block Signed-off-by: Steffen Maier Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

s390/cio: check the subchannel validity for dev_busid

2021-11-26T10:40:37+00:00

commit a4751f157c194431fae9e9c493f456df8272b871 upstream. Check the validity of subchanel before reading other fields in the schib. Fixes: d3683c055212 ("s390/cio: add dev_busid sysfs entry for each subchannel") CC: Reported-by: Cornelia Huck Signed-off-by: Vineeth Vijayan Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/20211105154451.847288-1-vneethv@linux.ibm.com Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

s390/cio: add dev_busid sysfs entry for each subchannel

2021-09-22T09:45:18+00:00

[ Upstream commit d3683c055212bf910d4e318f7944910ce10dbee6 ] Introduce dev_busid, which exports the device-id associated with the io-subchannel (and message-subchannel). The dev_busid indicates that of the device which may be physically installed on the corrosponding subchannel. The dev_busid value "none" indicates that the subchannel is not valid, there is no I/O device currently associated with the subchannel. The dev_busid information would be helpful to write device-specific udev-rules associated with the subchannel. The dev_busid interface would be available even when the sch is not bound to any driver or if there is no operational device connected on it. Hence this attribute can be used to write udev-rules which are specific to the device associated with the subchannel. Signed-off-by: Vineeth Vijayan Reviewed-by: Peter Oberparleiter Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/sclp_vt220: fix console name to match device

2021-07-20T14:17:50+00:00

[ Upstream commit b7d91d230a119fdcc334d10c9889ce9c5e15118b ] Console name reported in /proc/consoles: ttyS1 -W- (EC p ) 4:65 does not match the char device name: crw--w---- 1 root root 4, 65 May 17 12:18 /dev/ttysclp0 so debian-installer inside a QEMU s390x instance gets confused and fails to start with the following error: steal-ctty: No such file or directory Signed-off-by: Valentin Vidic Link: https://lore.kernel.org/r/20210427194010.9330-1-vvidic@valentin-vidic.from.hr Signed-off-by: Christian Borntraeger Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

s390/cio: dont call css_wait_for_slow_path() inside a lock

2021-07-20T14:17:29+00:00

commit c749d8c018daf5fba6dfac7b6c5c78b27efd7d65 upstream. Currently css_wait_for_slow_path() gets called inside the chp->lock. The path-verification-loop of slowpath inside this lock could lead to deadlock as reported by the lockdep validator. The ccw_device_get_chp_desc() during the instance of a device-set-online would try to acquire the same 'chp->lock' to read the chp->desc. The instance of this function can get called from multiple scenario, like probing or setting-device online manually. This could, in some corner-cases lead to the deadlock. lockdep validator reported this as, CPU0 CPU1 ---- ---- lock(&chp->lock); lock(kn->active#43); lock(&chp->lock); lock((wq_completion)cio); The chp->lock was introduced to serialize the access of struct channel_path. This lock is not needed for the css_wait_for_slow_path() function, so invoke the slow-path function outside this lock. Fixes: b730f3a93395 ("[S390] cio: add lock to struct channel_path") Cc: Reviewed-by: Peter Oberparleiter Signed-off-by: Vineeth Vijayan Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

s390/dasd: fix hanging IO request during DASD driver unbind

2021-03-17T15:34:31+00:00

commit 66f669a272898feb1c69b770e1504aa2ec7723d1 upstream. Prevent that an IO request is build during device shutdown initiated by a driver unbind. This request will never be able to be processed or canceled and will hang forever. This will lead also to a hanging unbind. Fix by checking not only if the device is in READY state but also check that there is no device offline initiated before building a new IO request. Fixes: e443343e509a ("s390/dasd: blk-mq conversion") Cc: # v4.14+ Signed-off-by: Stefan Haberland Tested-by: Bjoern Walk Reviewed-by: Jan Hoeppner Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

s390/dasd: fix hanging DASD driver unbind

2021-03-17T15:34:31+00:00

commit 7d365bd0bff3c0310c39ebaffc9a8458e036d666 upstream. In case of an unbind of the DASD device driver the function dasd_generic_remove() is called which shuts down the device. Among others this functions removes the int_handler from the cdev. During shutdown the device cancels all outstanding IO requests and waits for completion of the clear request. Unfortunately the clear interrupt will never be received when there is no interrupt handler connected. Fix by moving the int_handler removal after the call to the state machine where no request or interrupt is outstanding. Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland Tested-by: Bjoern Walk Reviewed-by: Jan Hoeppner Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman