linux/drivers/scsi/ufs
Venkat Gopalakrishnan f2a785ac23 scsi: ufshcd: Fix race between clk scaling and ungate work
The ungate work turns on the clock before it exits hibern8, if the link
was put in hibern8 during clock gating work.  There occurs a race
condition when clock scaling work calls ufshcd_hold() to make sure low
power states cannot be entered, but that returns by checking only
whether the clocks are on.  This causes the clock scaling work to issue
UIC commands when the link is in hibern8 causing failures. Make sure we
exit hibern8 state before returning from ufshcd_hold().

Callstacks for race condition:

 ufshcd_scale_gear
 ufshcd_devfreq_scale
 ufshcd_devfreq_target
 update_devfreq
 devfreq_monitor
 process_one_work
 worker_thread
 kthread
 ret_from_fork

 ufshcd_uic_hibern8_exit
 ufshcd_ungate_work
 process_one_work
 worker_thread
 kthread
 ret_from_fork

Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08 17:29:58 -05:00
..
Kconfig scsi: ufs: Kconfig fix 2016-09-29 21:57:08 -04:00
Makefile ufs: add TC G210 pci driver 2016-07-12 23:16:31 -04:00
tc-dwc-g210-pci.c ufs: add TC G210 pci driver 2016-07-12 23:16:31 -04:00
tc-dwc-g210-pltfrm.c ufs: add TC G210 platform driver 2016-07-12 23:16:31 -04:00
tc-dwc-g210.c scsi: ufs: Add missing header dependencies for tc-dwc-g210 2016-09-04 01:28:08 -04:00
tc-dwc-g210.h ufs: add support for Synopsys G210 Test Chip 2016-07-12 23:16:31 -04:00
ufs_quirks.h scsi: ufs: Enable no vccq quirk for skhynix device 2016-09-28 01:08:05 -04:00
ufs-qcom.c scsi: ufshcd: Fix possible unclocked register access 2016-11-08 17:29:47 -05:00
ufs-qcom.h scsi: ufs-qcom: add printouts of testbus debug registers 2016-03-14 21:04:45 -04:00
ufs.h scsi: ufs: fix bugs related to null pointer access and array size 2016-11-08 17:29:58 -05:00
ufshcd-dwc.c ufs: Adding license info do tc-dwc-g210 and ufshcd-dwc to enable loadable module 2016-07-12 23:16:31 -04:00
ufshcd-dwc.h ufs: add support for DesignWare Controller 2016-07-12 23:16:31 -04:00
ufshcd-pci.c SCSI / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM 2014-12-15 15:11:06 +01:00
ufshcd-pltfrm.c ufs: fixed typo in ufshcd-pltfrm 2016-07-12 23:16:31 -04:00
ufshcd-pltfrm.h scsi: ufs: make the UFS variant a platform device 2015-11-09 18:00:02 -05:00
ufshcd.c scsi: ufshcd: Fix race between clk scaling and ungate work 2016-11-08 17:29:58 -05:00
ufshcd.h scsi: ufshcd: Fix possible unclocked register access 2016-11-08 17:29:47 -05:00
ufshci-dwc.h ufs: add support for DesignWare Controller 2016-07-12 23:16:31 -04:00
ufshci.h ufs: add link status to ufshci 2016-07-12 23:16:31 -04:00
unipro.h ufs: add unipro attributes 2016-07-12 23:16:31 -04:00