1. 23 Jan, 2009 4 commits
    • Heiko Carstens's avatar
      [S390] etr/stp: fix possible deadlock · 179cb81a
      Heiko Carstens authored
      Precreate stop_machine threads in case the machine supports ETR/STP.
      Otherwise we might deadlock if a time sync operation gets scheduled
      and the creation of stop_machine threads would cause disk I/O.
      This is just the minimal fix.
      The real fix would be to only precreate stop_machine threads if
      ETR/STP is actually used. But that would be a rather large and
      complicated patch.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      179cb81a
    • Heiko Carstens's avatar
      [S390] cputime: fix lowcore initialization on cpu hotplug · f9a2f797
      Heiko Carstens authored
      On (initial) cpu hotplug the lowcore values for user_timer and
      system_timer don't get initialized like they would get on each
      process schedule.
      On initial start of secondary cpus this leads to the situation
      where per thread user/system_timer values are larger than the
      corresponding contents of the lowcore. When later calculating
      time spent in user/system context the result can be negative.
      
      So for cpu hotplug we should manually initialize lowcore values.
      
      Fixes this bug:
      
      Kernel BUG at 000ec080 [verbose debug info unavailable]
      fixpoint divide exception: 0009 [#1] PREEMPT SMP
      Modules linked in:
      CPU: 10 Not tainted 2.6.28 #4
      Process sysctl (pid: 975, task: 3fa752e0, ksp: 3fbebca0)
      Krnl PSW : 070c1000 800ec080 (show_stat+0x390/0x5fc)
                 R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0
      Krnl GPRS: 7fffffff fefc7ce5 3faec080 003879ae
                 00000001 01388000 7fffffff 01388000
                 00000000 00000000 0049ad50 3fbebcf8
                 01388000 002f51a8 800ec1fe 3fbebcf8
      Krnl Code: 800ec076: 9001b188           stm     %r0,%r1,392(%r11)
                 800ec07a: 9801b0c0           lm      %r0,%r1,192(%r11)
                 800ec07e: 1d05               dr      %r0,%r5
                >800ec080: 9001b0c0           stm     %r0,%r1,192(%r11)
                 800ec084: 5860b0c4           l       %r6,196(%r11)
                 800ec088: 1806               lr      %r0,%r6
                 800ec08a: 8c800001           srdl    %r8,1
                 800ec08e: 1d87               dr      %r8,%r7
      Call Trace:
      ([<00000000000ec1ee>] show_stat+0x4fe/0x5fc)
       [<00000000000c13e8>] seq_read+0xc4/0x3ac
       [<00000000000e4796>] proc_reg_read+0x6e/0x9c
       [<00000000000a6a44>] vfs_read+0x78/0x100
       [<00000000000a6ba8>] sys_read+0x40/0x80
       [<00000000000234a8>] sysc_do_restart+0x1a/0x1e
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      f9a2f797
    • Michael Holzheu's avatar
      [S390] fix compat sigaltstack syscall table entry · e9a4e9d5
      Michael Holzheu authored
      When 31 bit user space programs call sigaltstack on a 64 bit Linux
      OS, the system call returns -1 with errno=EFAULT. The 31 bit pointer passed
      to the system call is extended to 64 bit, but the high order bits are not
      set to zero. The kernel detects the invalid user space pointer and
      returns -EFAULT. To solve the problem, sys32_sigaltstack_wrapper()
      instead of sys32_sigaltstack() has to be called. The wrapper function sets
      the high order bits to zero.
      Signed-off-by: default avatarMichael Holzheu <holzheu@linux.vnet.ibm.com>
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      e9a4e9d5
    • Heiko Carstens's avatar
      [S390] personality: fix personality loss on execve · 03e4c49f
      Heiko Carstens authored
      Use the personality() macro to mask out all bits that are not
      relevant for the personality type.
      The personality field contains bits for other things as well,
      so without masking out the not relevalent bits the comparison
      won't do what is expected.
      Reported-by: default avatarAndreas Krebbel <krebbel@linux.vnet.ibm.com>
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      03e4c49f
  2. 17 Jan, 2009 5 commits
  3. 16 Jan, 2009 31 commits