1. 30 Oct, 2011 1 commit
  2. 24 Jul, 2011 1 commit
    • Martin Schwidefsky's avatar
      [S390] kvm guest address space mapping · e5992f2e
      Martin Schwidefsky authored
      
      
      Add code that allows KVM to control the virtual memory layout that
      is seen by a guest. The guest address space uses a second page table
      that shares the last level pte-tables with the process page table.
      If a page is unmapped from the process page table it is automatically
      unmapped from the guest page table as well.
      
      The guest address space mapping starts out empty, KVM can map any
      individual 1MB segments from the process virtual memory to any 1MB
      aligned location in the guest virtual memory. If a target segment in
      the process virtual memory does not exist or is unmapped while a
      guest mapping exists the desired target address is stored as an
      invalid segment table entry in the guest page table.
      The population of the guest page table is fault driven.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      e5992f2e
  3. 01 Jul, 2011 1 commit
    • Peter Zijlstra's avatar
      perf: Remove the nmi parameter from the swevent and overflow interface · a8b0ca17
      Peter Zijlstra authored
      
      
      The nmi parameter indicated if we could do wakeups from the current
      context, if not, we would set some state and self-IPI and let the
      resulting interrupt do the wakeup.
      
      For the various event classes:
      
        - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
          the PMI-tail (ARM etc.)
        - tracepoint: nmi=0; since tracepoint could be from NMI context.
        - software: nmi=[0,1]; some, like the schedule thing cannot
          perform wakeups, and hence need 0.
      
      As one can see, there is very little nmi=1 usage, and the down-side of
      not using it is that on some platforms some software events can have a
      jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).
      
      The up-side however is that we can remove the nmi parameter and save a
      bunch of conditionals in fast paths.
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Michael Cree <mcree@orcon.net.nz>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
      Cc: Anton Blanchard <anton@samba.org>
      Cc: Eric B Munson <emunson@mgebm.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Wessel <jason.wessel@windriver.com>
      Cc: Don Zickus <dzickus@redhat.com>
      Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
      
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      a8b0ca17
  4. 26 May, 2011 5 commits
  5. 23 May, 2011 3 commits
    • Heiko Carstens's avatar
      [S390] pfault: cleanup code · 7dd8fe1f
      Heiko Carstens authored
      
      
      Small code cleanup.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      7dd8fe1f
    • Heiko Carstens's avatar
      [S390] pfault: cpu hotplug vs missing completion interrupts · f2db2e6c
      Heiko Carstens authored
      
      
      On cpu hot remove a PFAULT CANCEL command is sent to the hypervisor
      which in turn will cancel all outstanding pfault requests that have
      been issued on that cpu (the same happens with a SIGP cpu reset).
      
      The result is that we end up with uninterruptible processes where
      the interrupt that would wake up these processes never arrives.
      
      In order to solve this all processes which wait for a pfault
      completion interrupt get woken up after a cpu hot remove. The worst
      case that could happen is that they fault again and in turn need to
      wait again.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      f2db2e6c
    • Martin Schwidefsky's avatar
      [S390] Remove data execution protection · 043d0708
      Martin Schwidefsky authored
      
      
      The noexec support on s390 does not rely on a bit in the page table
      entry but utilizes the secondary space mode to distinguish between
      memory accesses for instructions vs. data. The noexec code relies
      on the assumption that the cpu will always use the secondary space
      page table for data accesses while it is running in the secondary
      space mode. Up to the z9-109 class machines this has been the case.
      Unfortunately this is not true anymore with z10 and later machines.
      The load-relative-long instructions lrl, lgrl and lgfrl access the
      memory operand using the same addressing-space mode that has been
      used to fetch the instruction.
      This breaks the noexec mode for all user space binaries compiled
      with march=z10 or later. The only option is to remove the current
      noexec support.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      043d0708
  6. 29 Apr, 2011 1 commit
  7. 20 Apr, 2011 1 commit
    • Heiko Carstens's avatar
      [S390] pfault: fix token handling · e35c76cd
      Heiko Carstens authored
      f6649a7e
      
       "[S390] cleanup lowcore access from external interrupts" changed
      handling of external interrupts. Instead of letting the external interrupt
      handlers accessing the per cpu lowcore the entry code of the kernel reads
      already all fields that are necessary and passes them to the handlers.
      The pfault interrupt handler was incorrectly converted. It tries to
      dereference a value which used to be a pointer to a lowcore field. After
      the conversion however it is not anymore the pointer to the field but its
      content. So instead of a dereference only a cast is needed to get the
      task pointer that caused the pfault.
      
      Fixes a NULL pointer dereference and a subsequent kernel crash:
      
      Unable to handle kernel pointer dereference at virtual kernel address (null)
      Oops: 0004 [#1] SMP
      Modules linked in: nfsd exportfs nfs lockd fscache nfs_acl auth_rpcgss sunrpc
                         loop qeth_l3 qeth vmur ccwgroup ext3 jbd mbcache dm_mod
                         dasd_eckd_mod dasd_diag_mod dasd_mod
      CPU: 0 Not tainted 2.6.38-2-s390x #1
      Process cron (pid: 1106, task: 000000001f962f78, ksp: 000000001fa0f9d0)
      Krnl PSW : 0404200180000000 000000000002c03e (pfault_interrupt+0xa2/0x138)
                 R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
      Krnl GPRS: 0000000000000000 0000000000000001 0000000000000000 0000000000000001
                 000000001f962f78 0000000000518968 0000000090000002 000000001ff03280
                 0000000000000000 000000000064f000 000000001f962f78 0000000000002603
                 0000000006002603 0000000000000000 000000001ff7fe68 000000001ff7fe48
      Krnl Code: 000000000002c036: 5820d010            l       %r2,16(%r13)
                 000000000002c03a: 1832                lr      %r3,%r2
                 000000000002c03c: 1a31                ar      %r3,%r1
                >000000000002c03e: ba23d010            cs      %r2,%r3,16(%r13)
                 000000000002c042: a744fffc            brc     4,2c03a
                 000000000002c046: a7290002            lghi    %r2,2
                 000000000002c04a: e320d0000024        stg     %r2,0(%r13)
                 000000000002c050: 07f0                bcr     15,%r0
      Call Trace:
       ([<000000001f962f78>] 0x1f962f78)
        [<000000000001acda>] do_extint+0xf6/0x138
        [<000000000039b6ca>] ext_no_vtime+0x30/0x34
        [<000000007d706e04>] 0x7d706e04
      Last Breaking-Event-Address:
        [<0000000000000000>] 0x0
      
      For stable maintainers:
      the first kernel which contains this bug is 2.6.37.
      Reported-by: default avatarStephen Powell <zlinuxman@wowway.com>
      Cc: Jonathan Nieder <jrnieder@gmail.com>
      Cc: stable@kernel.org
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      e35c76cd
  8. 31 Mar, 2011 1 commit
  9. 05 Jan, 2011 3 commits
  10. 25 Oct, 2010 5 commits
  11. 17 May, 2010 1 commit
    • Heiko Carstens's avatar
      [S390] debug: enable exception-trace debug facility · ab3c68ee
      Heiko Carstens authored
      
      
      The exception-trace facility on x86 and other architectures prints
      traces to dmesg whenever a user space application crashes.
      s390 has such a feature since ages however it is called
      userprocess_debug and is enabled differently.
      This patch makes sure that whenever one of the two procfs files
      
      /proc/sys/kernel/userprocess_debug
      /proc/sys/debug/exception-trace
      
      is modified the contents of the second one changes as well.
      That way we keep backwards compatibilty but also support the same
      interface like other architectures do.
      Besides that the output of the traces is improved since it will now
      also contain the corresponding filename of the vma (when available)
      where the process caused a fault or trap.
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      ab3c68ee
  12. 26 Feb, 2010 2 commits
  13. 07 Dec, 2009 6 commits
  14. 21 Sep, 2009 1 commit
    • Ingo Molnar's avatar
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      Ingo Molnar authored
      
      
      Bye-bye Performance Counters, welcome Performance Events!
      
      In the past few months the perfcounters subsystem has grown out its
      initial role of counting hardware events, and has become (and is
      becoming) a much broader generic event enumeration, reporting, logging,
      monitoring, analysis facility.
      
      Naming its core object 'perf_counter' and naming the subsystem
      'perfcounters' has become more and more of a misnomer. With pending
      code like hw-breakpoints support the 'counter' name is less and
      less appropriate.
      
      All in one, we've decided to rename the subsystem to 'performance
      events' and to propagate this rename through all fields, variables
      and API names. (in an ABI compatible fashion)
      
      The word 'event' is also a bit shorter than 'counter' - which makes
      it slightly more convenient to write/handle as well.
      
      Thanks goes to Stephane Eranian who first observed this misnomer and
      suggested a rename.
      
      User-space tooling and ABI compatibility is not affected - this patch
      should be function-invariant. (Also, defconfigs were not touched to
      keep the size down.)
      
      This patch has been generated via the following script:
      
        FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
      
        sed -i \
          -e 's/PERF_EVENT_/PERF_RECORD_/g' \
          -e 's/PERF_COUNTER/PERF_EVENT/g' \
          -e 's/perf_counter/perf_event/g' \
          -e 's/nb_counters/nb_events/g' \
          -e 's/swcounter/swevent/g' \
          -e 's/tpcounter_event/tp_event/g' \
          $FILES
      
        for N in $(find . -name perf_counter.[ch]); do
          M=$(echo $N | sed 's/perf_counter/perf_event/g')
          mv $N $M
        done
      
        FILES=$(find . -name perf_event.*)
      
        sed -i \
          -e 's/COUNTER_MASK/REG_MASK/g' \
          -e 's/COUNTER/EVENT/g' \
          -e 's/\<event\>/event_id/g' \
          -e 's/counter/event/g' \
          -e 's/Counter/Event/g' \
          $FILES
      
      ... to keep it as correct as possible. This script can also be
      used by anyone who has pending perfcounters patches - it converts
      a Linux kernel tree over to the new naming. We tried to time this
      change to the point in time where the amount of pending patches
      is the smallest: the end of the merge window.
      
      Namespace clashes were fixed up in a preparatory patch - and some
      stylistic fallout will be fixed up in a subsequent patch.
      
      ( NOTE: 'counters' are still the proper terminology when we deal
        with hardware registers - and these sed scripts are a bit
        over-eager in renaming them. I've undone some of that, but
        in case there's something left where 'counter' would be
        better than 'event' we can undo that on an individual basis
        instead of touching an otherwise nicely automated patch. )
      Suggested-by: default avatarStephane Eranian <eranian@google.com>
      Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: default avatarPaul Mackerras <paulus@samba.org>
      Reviewed-by: default avatarArjan van de Ven <arjan@linux.intel.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: <linux-arch@vger.kernel.org>
      LKML-Reference: <new-submission>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      cdd6c482
  15. 11 Sep, 2009 1 commit
  16. 12 Jul, 2009 1 commit
  17. 21 Jun, 2009 1 commit
  18. 12 Jun, 2009 1 commit
  19. 26 Mar, 2009 1 commit
  20. 30 Apr, 2008 1 commit
  21. 17 Apr, 2008 2 commits