1. 22 9月, 2012 1 次提交
  2. 03 5月, 2012 1 次提交
  3. 13 3月, 2012 1 次提交
  4. 27 1月, 2012 1 次提交
    • P
      bugs, x86: Fix printk levels for panic, softlockups and stack dumps · b0f4c4b3
      Prarit Bhargava 提交于
      rsyslog will display KERN_EMERG messages on a connected
      terminal.  However, these messages are useless/undecipherable
      for a general user.
      
      For example, after a softlockup we get:
      
       Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
       kernel:Stack:
      
       Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
       kernel:Call Trace:
      
       Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
       kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89
       d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89
      
      This happens because the printk levels for these messages are
      incorrect. Only an informational message should be displayed on
      a terminal.
      
      I modified the printk levels for various messages in the kernel
      and tested the output by using the drivers/misc/lkdtm.c kernel
      modules (ie, softlockups, panics, hard lockups, etc.) and
      confirmed that the console output was still the same and that
      the output to the terminals was correct.
      
      For example, in the case of a softlockup we now see the much
      more informative:
      
       Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ...
       BUG: soft lockup - CPU4 stuck for 60s!
      
      instead of the above confusing messages.
      
      AFAICT, the messages no longer have to be KERN_EMERG.  In the
      most important case of a panic we set console_verbose().  As for
      the other less severe cases the correct data is output to the
      console and /var/log/messages.
      
      Successfully tested by me using the drivers/misc/lkdtm.c module.
      Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
      Cc: dzickus@redhat.com
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
      b0f4c4b3
  5. 05 12月, 2011 1 次提交
  6. 29 9月, 2011 1 次提交
    • J
      x86-64: Don't apply destructive erratum workaround on unaffected CPUs · e05139f2
      Jan Beulich 提交于
      Erratum 93 applies to AMD K8 CPUs only, and its workaround
      (forcing the upper 32 bits of %rip to all get set under certain
      conditions) is actually getting in the way of analyzing page
      faults occurring during EFI physical mode runtime calls (in
      particular the page table walk shown is completely unrelated to
      the actual fault). This is because typically EFI runtime code
      lives in the space between 2G and 4G, which - modulo the above
      manipulation - is likely to overlap with the kernel or modules
      area.
      
      While even for the other errata workarounds their taking effect
      could be limited to just the affected CPUs, none of them appears
      to be destructive, and they're generally getting called only
      outside of performance critical paths, so they're being left
      untouched.
      Signed-off-by: NJan Beulich <jbeulich@suse.com>
      Link: http://lkml.kernel.org/r/4E835FE30200007800058464@nat28.tlf.novell.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
      e05139f2
  7. 16 8月, 2011 2 次提交
  8. 11 8月, 2011 1 次提交
  9. 05 8月, 2011 1 次提交
  10. 01 7月, 2011 1 次提交
    • P
      perf: Remove the nmi parameter from the swevent and overflow interface · a8b0ca17
      Peter Zijlstra 提交于
      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: NPeter 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.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      a8b0ca17
  11. 26 5月, 2011 1 次提交
  12. 25 5月, 2011 1 次提交
    • K
      x86,mm: make pagefault killable · 37b23e05
      KOSAKI Motohiro 提交于
      When an oom killing occurs, almost all processes are getting stuck at the
      following two points.
      
      	1) __alloc_pages_nodemask
      	2) __lock_page_or_retry
      
      1) is not very problematic because TIF_MEMDIE leads to an allocation
      failure and getting out from page allocator.
      
      2) is more problematic.  In an OOM situation, zones typically don't have
      page cache at all and memory starvation might lead to greatly reduced IO
      performance.  When a fork bomb occurs, TIF_MEMDIE tasks don't die quickly,
      meaning that a fork bomb may create new process quickly rather than the
      oom-killer killing it.  Then, the system may become livelocked.
      
      This patch makes the pagefault interruptible by SIGKILL.
      Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Minchan Kim <minchan.kim@gmail.com>
      Cc: Matthew Wilcox <willy@linux.intel.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      37b23e05
  13. 21 5月, 2011 1 次提交
    • L
      sanitize <linux/prefetch.h> usage · 268bb0ce
      Linus Torvalds 提交于
      Commit e66eed65 ("list: remove prefetching from regular list
      iterators") removed the include of prefetch.h from list.h, which
      uncovered several cases that had apparently relied on that rather
      obscure header file dependency.
      
      So this fixes things up a bit, using
      
         grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]')
         grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]')
      
      to guide us in finding files that either need <linux/prefetch.h>
      inclusion, or have it despite not needing it.
      
      There are more of them around (mostly network drivers), but this gets
      many core ones.
      Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      268bb0ce
  14. 10 3月, 2011 2 次提交
    • A
      x86/mm: Fix pgd_lock deadlock · a79e53d8
      Andrea Arcangeli 提交于
      It's forbidden to take the page_table_lock with the irq disabled
      or if there's contention the IPIs (for tlb flushes) sent with
      the page_table_lock held will never run leading to a deadlock.
      
      Nobody takes the pgd_lock from irq context so the _irqsave can be
      removed.
      Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Acked-by: NRik van Riel <riel@redhat.com>
      Tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: <stable@kernel.org>
      LKML-Reference: <201102162345.p1GNjMjm021738@imap1.linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a79e53d8
    • A
      x86/mm: Handle mm_fault_error() in kernel space · f8626854
      Andrey Vagin 提交于
      mm_fault_error() should not execute oom-killer, if page fault
      occurs in kernel space.  E.g. in copy_from_user()/copy_to_user().
      
      This would happen if we find ourselves in OOM on a
      copy_to_user(), or a copy_from_user() which faults.
      
      Without this patch, the kernels hangs up in copy_from_user(),
      because OOM killer sends SIG_KILL to current process, but it
      can't handle a signal while in syscall, then the kernel returns
      to copy_from_user(), reexcute current command and provokes
      page_fault again.
      
      With this patch the kernel return -EFAULT from copy_from_user().
      
      The code, which checks that page fault occurred in kernel space,
      has been copied from do_sigbus().
      
      This situation is handled by the same way on powerpc, xtensa,
      tile, ...
      Signed-off-by: NAndrey Vagin <avagin@openvz.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: <stable@kernel.org>
      LKML-Reference: <201103092322.p29NMNPH001682@imap1.linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f8626854
  15. 27 10月, 2010 2 次提交
  16. 21 10月, 2010 1 次提交
  17. 20 10月, 2010 1 次提交
  18. 15 10月, 2010 1 次提交
    • F
      x86: Barf when vmalloc and kmemcheck faults happen in NMI · ebc8827f
      Frederic Weisbecker 提交于
      In x86, faults exit by executing the iret instruction, which then
      reenables NMIs if we faulted in NMI context. Then if a fault
      happens in NMI, another NMI can nest after the fault exits.
      
      But we don't yet support nested NMIs because we have only one NMI
      stack. To prevent from that, check that vmalloc and kmemcheck
      faults don't happen in this context. Most of the other kernel faults
      in NMIs can be more easily spotted by finding explicit
      copy_from,to_user() calls on review.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      ebc8827f
  19. 08 10月, 2010 1 次提交
    • A
      x86: HWPOISON: Report correct address granuality for huge hwpoison faults · f672b49b
      Andi Kleen 提交于
      An earlier patch fixed the hwpoison fault handling to encode the
      huge page size in the fault code of the page fault handler.
      
      This is needed to report this information in SIGBUS to user space.
      
      This is a straight forward patch to pass this information
      through to the signal handling in the x86 specific fault.c
      
      Cc: x86@kernel.org
      Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: fengguang.wu@intel.com
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      f672b49b
  20. 27 8月, 2010 2 次提交
  21. 14 8月, 2010 1 次提交
    • L
      x86: don't send SIGBUS for kernel page faults · 96054569
      Linus Torvalds 提交于
      It's wrong for several reasons, but the most direct one is that the
      fault may be for the stack accesses to set up a previous SIGBUS.  When
      we have a kernel exception, the kernel exception handler does all the
      fixups, not some user-level signal handler.
      
      Even apart from the nested SIGBUS issue, it's also wrong to give out
      kernel fault addresses in the signal handler info block, or to send a
      SIGBUS when a system call already returns EFAULT.
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      96054569
  22. 23 11月, 2009 1 次提交
  23. 21 9月, 2009 1 次提交
    • I
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      Ingo Molnar 提交于
      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: NStephane Eranian <eranian@google.com>
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NPaul Mackerras <paulus@samba.org>
      Reviewed-by: NArjan 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: NIngo Molnar <mingo@elte.hu>
      cdd6c482
  24. 16 9月, 2009 1 次提交
  25. 30 8月, 2009 1 次提交
  26. 11 7月, 2009 1 次提交
    • R
      x86: Remove spurious printk level from segfault message · a1a08d1c
      Roland Dreier 提交于
      Since commit 5fd29d6c ("printk: clean up handling of log-levels
      and newlines"), the kernel logs segfaults like:
      
          <6>gnome-power-man[24509]: segfault at 20 ip 00007f9d4950465a sp 00007fffbb50fc70 error 4 in libgobject-2.0.so.0.2103.0[7f9d494f7000+45000]
      
      with the extra "<6>" being KERN_INFO.  This happens because the
      printk in show_signal_msg() started with KERN_CONT and then
      used "%s" to pass in the real level; and KERN_CONT is no longer
      an empty string, and printk only pays attention to the level at
      the very beginning of the format string.
      
      Therefore, remove the KERN_CONT from this printk, since it is
      now actively causing problems (and never really made any
      sense).
      Signed-off-by: NRoland Dreier <roland@digitalvampire.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      LKML-Reference: <874otjitkj.fsf@shaolin.home.digitalvampire.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a1a08d1c
  27. 09 7月, 2009 1 次提交
  28. 29 6月, 2009 1 次提交
  29. 22 6月, 2009 1 次提交
  30. 16 6月, 2009 1 次提交
    • I
      x86: mm: Read cr2 before prefetching the mmap_lock · 5dfaf90f
      Ingo Molnar 提交于
      Prefetch instructions can generate spurious faults on certain
      models of older CPUs. The faults themselves cannot be stopped
      and they can occur pretty much anywhere - so the way we solve
      them is that we detect certain patterns and ignore the fault.
      
      There is one small path of code where we must not take faults
      though: the #PF handler execution leading up to the reading
      of the CR2 (the faulting address). If we take a fault there
      then we destroy the CR2 value (with that of the prefetching
      instruction's) and possibly mishandle user-space or
      kernel-space pagefaults.
      
      It turns out that in current upstream we do exactly that:
      
      	prefetchw(&mm->mmap_sem);
      
      	/* Get the faulting address: */
      	address = read_cr2();
      
      This is not good.
      
      So turn around the order: first read the cr2 then prefetch
      the lock address. Reading cr2 is plenty fast (2 cycles) so
      delaying the prefetch by this amount shouldnt be a big issue
      performance-wise.
      
      [ And this might explain a mystery fault.c warning that sometimes
        occurs on one an old AMD/Semptron based test-system i have -
        which does have such prefetch problems. ]
      
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Pekka Enberg <penberg@cs.helsinki.fi>
      Cc: Vegard Nossum <vegard.nossum@gmail.com>
      Cc: Jeremy Fitzhardinge <jeremy@goop.org>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      LKML-Reference: <20090616030522.GA22162@Krystal>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5dfaf90f
  31. 15 6月, 2009 1 次提交
    • V
      x86: add hooks for kmemcheck · f8561296
      Vegard Nossum 提交于
      The hooks that we modify are:
      - Page fault handler (to handle kmemcheck faults)
      - Debug exception handler (to hide pages after single-stepping
        the instruction that caused the page fault)
      
      Also redefine memset() to use the optimized version if kmemcheck is
      enabled.
      
      (Thanks to Pekka Enberg for minimizing the impact on the page fault
      handler.)
      
      As kmemcheck doesn't handle MMX/SSE instructions (yet), we also disable
      the optimized xor code, and rely instead on the generic C implementation
      in order to avoid false-positive warnings.
      Signed-off-by: NVegard Nossum <vegardno@ifi.uio.no>
      
      [whitespace fixlet]
      Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      
      [rebased for mainline inclusion]
      Signed-off-by: NVegard Nossum <vegardno@ifi.uio.no>
      f8561296
  32. 11 6月, 2009 1 次提交
  33. 03 5月, 2009 1 次提交
  34. 09 4月, 2009 1 次提交
  35. 06 4月, 2009 2 次提交