ORACLE在HP-UX下的系列問題處理(49)
2024-08-29 13:39:59
供稿：網友
HP-UX: 在HP-UX 10.20上安裝Oracle 7.3.3版時掛起。
問題描述
我使用運行HP-UX 10.20的9000/K，我試圖在上面安裝Oracle 7.3.3版，但安裝掛起，我們找不到原因。
是否能夠為我提供幫助？
配置信息
操作系統 - HP-UX
版本 - 10.20
硬件系統 - HP9000
系列 -
解決方法
問題是由于在PA8000系統上使用VxFS Direct IO和SHMEM_MAGIC時的死鎖引起的。
使用下面的方法禁用superpage exec():
# adb -w /stand/vmunix
allow_superpage_text?W 0
這個規避方法應當可以解決這個問題。
缺陷實際上在VxFS代碼中。VX_DIRECT IO特性的設計只適用于用戶IO (UIOSEG_USER)，問題在于VxFS不檢查UIOSEG_PAGEIN IO，然后有可能在保持區域RW鎖定的同時，調用vx_dio_iovec()/vx_memiolock()及exec_superpage_text()，從而導致到達useracc()/pfault()/findPReg()/lock_write()時出現死鎖：
save+0x0
_swtch+0x2e0
real_sleep+0x2f4
_sleep+0x14
lock_write+0x2c8
findpreg+0xb0 <<< 再次調用 reglock()!!!
pfault+0x98
lacc+0x68
vx_memiolock+0x3c
vx_dio_iovec+0x420
vx_dio_rdwri+0x104
vx_dio_readi+0x8c
vx_read1+0x2e4 <<< 調用 vx_dio_check()
vx_rdwr+0x16c
vn_rdwr+0x8c <<< UIOSEG_PAGEIN
exec_superpage_text+0x168 <<< 調用 reglock()
getxfile+0x478
execve+0xb70
syscall+0x1a4
解決方法是將vx_dio_check()中的EINVAL返回non-UIOSEG_USER段的IO，然后vx_read1()將返回標準IO通道，從而避免死鎖。
針對此問題的SR 1653223669已經打開。
.........following with all English text ....
A4747242 [A4747242/TRAK/English]
HP-UX: Installation of Oracle release 7.3.3 hangs with HP-UX 10.20.
Problem Description
I have a 9000/K with HP-UX 10.20 on which I am trying to install Oracle release 7.3.3. The installation hangs and we cannot find the cause.
Can you help?
Configuration Info
Operating System - HP-UX
Version - 10.20
Hardware System - HP9000
Series -
Solution
The problem is caused by a deadlock when using VxFS Direct IO and SHMEM_MAGIC on PA8000 systems.
Use this work-around to disable superpage exec():
# adb -w /stand/vmunix
allow_superpage_text?W 0
The work-around should solve the problem.
The defect is actually in the VxFS code. The VX_DIRECT IO feature is designed to work for user IOs only(UIOSEG_USER). The problem is that VxFS does not check for UIOSEG_PAGEIN IOs. It is then possible to call vx_dio_iovec()/vx_memiolock() along the exec_superpage_text()
while holding the region RW lock, thus resulting in a deadlock when
reaching useracc()/pfault()/findpreg()/lock_write():
save+0x0
_swtch+0x2e0
real_sleep+0x2f4
_sleep+0x14
lock_write+0x2c8
findpreg+0xb0 <<< calling reglock() again !
!!
pfault+0x98
lacc+0x68
vx_memiolock+0x3c
vx_dio_iovec+0x420
vx_dio_rdwri+0x104
vx_dio_readi+0x8c
vx_read1+0x2e4 <<< called vx_dio_check()
vx_rdwr+0x16c
vn_rdwr+0x8c <<< UIOSEG_PAGEIN
exec_superpage_text+0x168 <<< called reglock()
getxfile+0x478
execve+0xb70
syscall+0x1a4
The fix would be to return EINVAL in vx_dio_check() for IOs with non-UIOSEG_USER segments. Then vx_read1() would fall-back to the
regular IO path and this would avoid the deadlock.
SR 1653223669 has been opened for this problem.
