#11891 NORM 12.1.0: rtcwake: disable rtc alarm interrupt failed

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#11891: rtcwake: disable rtc alarm interrupt failed
--------------------+-------------------------------------------------------
 Reporter:  Quozl   |                 Owner:                                   
     Type:  defect  |                Status:  new                              
 Priority:  normal  |             Milestone:  12.1.0                           
Component:  kernel  |               Version:  Development build as of this date
 Keywords:          |           Next_action:  diagnose                         
 Verified:  0       |   Deployment_affected:                                   
Blockedby:          |              Blocking:                                   
--------------------+-------------------------------------------------------
 rtcwake emits an error after resume.

 {{{
 # rtcwake --seconds 10 --mode mem
 rtcwake: wakeup from "mem" using /dev/rtc0 at Thu Jan  1 12:24:20 1970
 rtcwake: disable rtc alarm interrupt failed: Invalid argument
 #
 }}}

 impact: low, it generates noise in runin logs.

 versions: XO-1.75 12.1.0 os11.

 diagnosis: /dev/rtc0 is opened as file descriptor 3, then a series of
 ioctl calls are made; RTC_RD_TIME, RTC_WKALM_SET, then RTC_AIE_OFF.  It is
 the last ioctl that fails with EINVAL.  An strace fragment follows:

 {{{
 sync()                                  = 0
 open("/sys/power/state", O_WRONLY|O_CREAT|O_TRUNC|O_LARGEFILE, 0666) = 4
 fstat64(4, {st_mode=S_IFREG|0644, st_size=4096, ...}) = 0
 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
 = 0x402d3000
 write(4, "mem\n", 4)                    = 4
 close(4)                                = 0
 munmap(0x402d3000, 4096)                = 0
 ioctl(3, PHN_GET_REGS or RTC_AIE_OFF, 0) = -1 EINVAL (Invalid argument)
 write(2, "rtcwake: ", 9)                = 9
 write(2, "disable rtc alarm interrupt failed", 34) = 34
 write(2, ": ", 2: )                       = 2
 write(2, "Invalid argument\n", 17)      = 17
 close(3)                                = 0
 exit_group(0)                           = ?
 }}}

-- 
Ticket URL: <http://dev.laptop.org/ticket/11891>
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