1da3b0141e
Calling ufshcd_rpm_{get/put}_sync() prior to ufshcd_scsi_add_wlus() being
called will trigger a NULL pointer dereference. This is because
hba->sdev_ufs_device is initialized in ufshcd_scsi_add_wlus().
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000348
Mem abort info:
ESR = 0x96000004
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x04: level 0 translation fault
Data abort info:
ISV = 0, ISS = 0x00000004
CM = 0, WnR = 0
[0000000000000348] user address but active_mm is swapper
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 91 Comm: kworker/u16:1 Not tainted 5.15.0-rc1-beanhuo-linaro-1423
Hardware name: MicronRB (DT)
Workqueue: events_unbound async_run_entry_fn
pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : pm_runtime_drop_link+0x128/0x338
lr : ufshpb_get_dev_info+0x8c/0x148
sp : ffff800012573c10
x29: ffff800012573c10 x28: 0000000000000000 x27: 0000000000000003
x26: ffff000001d21298 x25: 000000005abcea60 x24: ffff800011d89000
x23: 0000000000000001 x22: ffff000001d21880 x21: ffff000001ec9300
x20: 0000000000000004 x19: 0000000000000198 x18: ffffffffffffffff
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000041400
x14: 5eee00201100200a x13: 000000000000bb03 x12: 0000000000000000
x11: 0000000000000100 x10: 0200000000000000 x9 : bb0000021a162c01
x8 : 0302010021021003 x7 : 0000000000000000 x6 : ffff800012573af0
x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000200
x2 : 0000000000000348 x1 : 0000000000000348 x0 : ffff80001095308c
Call trace:
pm_runtime_drop_link+0x128/0x338
ufshpb_get_dev_info+0x8c/0x148
ufshcd_probe_hba+0xda0/0x11b8
ufshcd_async_scan+0x34/0x330
async_run_entry_fn+0x38/0x180
process_one_work+0x1f4/0x498
worker_thread+0x48/0x480
kthread+0x140/0x158
ret_from_fork+0x10/0x20
Code: 88027c01 35ffffa2 17fff6c4 f9800051 (885f7c40)
---[ end trace 2ba541335f595c95 ]
ufshpb_get_dev_info() is only called during asynchronous scanning and at
that time pm_runtime_get_sync() has been called:
...
/* Hold auto suspend until async scan completes */
pm_runtime_get_sync(dev);
atomic_set(&hba->scsi_block_reqs_cnt, 0);
...
ufshcd_async_scan()
ufshcd_probe_hba(hba, true);
ufshcd_device_params_init(hba);
ufshpb_get_dev_info();
...
pm_runtime_put_sync(hba->dev);
Remove ufshcd_rpm_{get/put}_sync() from ufshpb_get_dev_info() to fix this
problem.
Link: https://lore.kernel.org/r/20210929200640.828611-2-huobean@gmail.com
Fixes: 351b3a849ac7 ("scsi: ufs: ufshpb: Use proper power management API")
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.