diff options
| author | Manoj Kumar <manoj@linux.vnet.ibm.com> | 2015-12-14 15:07:23 -0600 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-01-06 20:55:01 -0500 |
| commit | b45cdbaf9f7f0486847c52f60747fb108724652a (patch) | |
| tree | c59b83e2a7384f2f9ab2a74a8e11223a114e85a5 /drivers/scsi/cxlflash/common.h | |
| parent | ee91e332a6e6e9b939f60f6e1bd72fb2def5290d (diff) | |
cxlflash: Resolve oops in wait_port_offline
If an async error interrupt is generated, and the error requires the FC
link to be reset, it cannot be performed in the interrupt context. So a
work element is scheduled to complete the link reset in a process
context. If either an EEH event or an escalation occurs in between when
the interrupt is generated and the scheduled work is started, the MMIO
space may no longer be available. This will cause an oops in the worker
thread.
[ 606.806583] NIP kthread_data+0x28/0x40
[ 606.806633] LR wq_worker_sleeping+0x30/0x100
[ 606.806694] Call Trace:
[ 606.806721] 0x50 (unreliable)
[ 606.806796] wq_worker_sleeping+0x30/0x100
[ 606.806884] __schedule+0x69c/0x8a0
[ 606.806959] schedule+0x44/0xc0
[ 606.807034] do_exit+0x770/0xb90
[ 606.807109] die+0x300/0x460
[ 606.807185] bad_page_fault+0xd8/0x150
[ 606.807259] handle_page_fault+0x2c/0x30
[ 606.807338] wait_port_offline.constprop.12+0x60/0x130 [cxlflash]
To prevent the problem space area from being unmapped, when there is
pending work, a mapcount (using the kref mechanism) is held. The
mapcount is released only when the work is completed. The last
reference release is tied to the unmapping service.
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/cxlflash/common.h')
| -rw-r--r-- | drivers/scsi/cxlflash/common.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h index c11cd193f896..5ada9268a450 100644 --- a/drivers/scsi/cxlflash/common.h +++ b/drivers/scsi/cxlflash/common.h @@ -165,6 +165,8 @@ struct afu { struct sisl_host_map __iomem *host_map; /* MC host map */ struct sisl_ctrl_map __iomem *ctrl_map; /* MC control map */ + struct kref mapcount; + ctx_hndl_t ctx_hndl; /* master's context handle */ u64 *hrrq_start; u64 *hrrq_end; |