1. 24 Jul, 2009 4 commits
    • Martin Schwidefsky's avatar
      [S390] vdso: clock_gettime of CLOCK_THREAD_CPUTIME_ID with noexec=on · 1277580f
      Martin Schwidefsky authored
      The combination of noexec=on and a clock_gettime call with clock id
      CLOCK_THREAD_CPUTIME_ID is broken. The vdso code switches to the
      access register mode to get access to the per-cpu data structure to
      execute the magic ectg instruction. After the ectg instruction the
      code always switches back to the primary mode but for noexec=on the
      correct mode is the secondary mode. The effect of the bug is that the
      user space program looses the access to all mappings without PROT_EXEC,
      e.g. the stack. The problem is fixed by restoring the mode that has
      been active before the switch to the access register mode.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      1277580f
    • Heiko Carstens's avatar
      [S390] vdso: fix per cpu area allocation · 3a6ba460
      Heiko Carstens authored
      vdso per cpu area allocation in smp_prepare_cpus() happens with GFP_KERNEL
      but irqs disabled. Triggers this one:
      
      Badness at kernel/lockdep.c:2280
      Modules linked in:
      CPU: 0 Not tainted 2.6.30 #2
      Process swapper (pid: 1, task: 000000003fe88000, ksp: 000000003fe87eb8)
      Krnl PSW : 0400c00180000000 0000000000083360 (lockdep_trace_alloc+0xec/0xf8)
      [...]
      Call Trace:
      ([<00000000000832b6>] lockdep_trace_alloc+0x42/0xf8)
       [<00000000000b1880>] __alloc_pages_internal+0x3e8/0x5c4
       [<00000000000b1b4a>] __get_free_pages+0x3a/0xb0
       [<0000000000026546>] vdso_alloc_per_cpu+0x6a/0x18c
       [<00000000005eff82>] smp_prepare_cpus+0x322/0x594
       [<00000000005e8232>] kernel_init+0x76/0x398
       [<000000000001bb1e>] kernel_thread_starter+0x6/0xc
       [<000000000001bb18>] kernel_thread_starter+0x0/0xc
      
      Fix this by moving the allocation out of the irqs disabled section.
      Reported-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      3a6ba460
    • Heiko Carstens's avatar
      [S390] hibernation: fix register corruption on machine checks · c63b196a
      Heiko Carstens authored
      swsusp_arch_suspend() actually saves all cpu register contents on
      hibernation.
      Machine checks must be disabled since swsusp_arch_suspend() stores
      register contents to their lowcore save areas. That's the same
      place where register contents on machine checks would be saved.
      To avoid register corruption disable machine checks.
      We must also disable machine checks in the new psw mask for
      program checks, since swsusp_arch_suspend() may generate program
      checks.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      c63b196a
    • Heiko Carstens's avatar
      [S390] hibernation: fix lowcore handling · 5f954c34
      Heiko Carstens authored
      Our swsusp_arch_suspend() backend implementation disables prefixing
      by setting the contents of the prefix register to 0.
      However afterwards common code functions are called which might
      access percpu data structures.
      Since the lowcore contains e.g. the percpu base pointer this isn't
      a good idea. So fix this by copying the hibernating cpu's lowcore to
      absolute address zero.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      5f954c34
  2. 23 Jul, 2009 1 commit
  3. 22 Jul, 2009 35 commits