1. 20 12月, 2007 4 次提交
  2. 19 12月, 2007 3 次提交
    • I
      x86: fix "Kernel panic - not syncing: IO-APIC + timer doesn't work!" · 4aae0702
      Ingo Molnar 提交于
      this is the tale of a full day spent debugging an ancient but elusive bug.
      
      after booting up thousands of random .config kernels, i finally happened
      to generate a .config that produced the following rare bootup failure
      on 32-bit x86:
      
      | ..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1
      | ..MP-BIOS bug: 8254 timer not connected to IO-APIC
      | ...trying to set up timer (IRQ0) through the 8259A ...  failed.
      | ...trying to set up timer as Virtual Wire IRQ... failed.
      | ...trying to set up timer as ExtINT IRQ... failed :(.
      | Kernel panic - not syncing: IO-APIC + timer doesn't work!  Boot with apic=debug
      | and send a report.  Then try booting with the 'noapic' option
      
      this bug has been reported many times during the years, but it was never
      reproduced nor fixed.
      
      the bug that i hit was extremely sensitive to .config details.
      
      First i did a .config-bisection - suspecting some .config detail.
      That led to CONFIG_X86_MCE: enabling X86_MCE magically made the bug disappear
      and the system would boot up just fine.
      
      Debugging my way through the MCE code ended up identifying two unlikely
      candidates: the thing that made a real difference to the hang was that
      X86_MCE did two printks:
      
       Intel machine check architecture supported.
       Intel machine check reporting enabled on CPU#1.
      
      Adding the same printks to a !CONFIG_X86_MCE kernel made the bug go away!
      
      this left timing as the main suspect: i experimented with adding various
      udelay()s to the arch/x86/kernel/io_apic_32.c:check_timer() function, and
      the race window turned out to be narrower than 30 microseconds (!).
      
      That made debugging especially funny, debugging without having printk
      ability before the bug hits is ... interesting ;-)
      
      eventually i started suspecting IRQ activities - those are pretty much the
      only thing that happen this early during bootup and have the timescale of
      a few dozen microseconds. Also, check_timer() changes the IRQ hardware
      in various creative ways, so the main candidate became IRQ0 interaction.
      
      i've added a counter to track timer irqs (on which core they arrived, at
      what exact time, etc.) and found that no timer IRQ would arrive after the
      bug condition hits - even if we re-enable IRQ0 and re-initialize the i8259A,
      but that we'd get a small number of timer irqs right around the time when we
      call the check_timer() function.
      
      Eventually i got the following backtrace triggered from debug code in the
      timer interrupt:
      
      ...trying to set up timer as Virtual Wire IRQ... failed.
      ...trying to set up timer as ExtINT IRQ...
      Pid: 1, comm: swapper Not tainted (2.6.24-rc5 #57)
      EIP: 0060:[<c044d57e>] EFLAGS: 00000246 CPU: 0
      EIP is at _spin_unlock_irqrestore+0x5/0x1c
      EAX: c0634178 EBX: 00000000 ECX: c4947d63 EDX: 00000246
      ESI: 00000002 EDI: 00010031 EBP: c04e0f2e ESP: f7c41df4
       DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
       CR0: 8005003b CR2: ffe04000 CR3: 00630000 CR4: 000006d0
       DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
       DR6: ffff0ff0 DR7: 00000400
        [<c05f5784>] setup_IO_APIC+0x9c3/0xc5c
      
      the spin_unlock() was called from init_8259A(). Wait ... we have an IRQ0
      entry while we are in the middle of setting up the local APIC, the i8259A
      and the PIT??
      
      That is certainly not how it's supposed to work! check_timer() was supposed
      to be called with irqs turned off - but this eroded away sometime in the
      past. This code would still work most of the time because this code runs
      very quickly, but just the right timing conditions are present and IRQ0
      hits in this small, ~30 usecs window, timer irqs stop and the system does
      not boot up. Also, given how early this is during bootup, the hang is
      very deterministic - but it would only occur on certain machines (and
      certain configs).
      
      The fix was quite simple: disable/restore interrupts properly in this
      function. With that in place the test-system now boots up just fine.
      
      (64-bit x86 io_apic_64.c had the same bug.)
      
      Phew! One down, only 1500 other kernel bugs are left ;-)
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      4aae0702
    • M
      x86: kprobes bugfix · 0b0122fa
      Masami Hiramatsu 提交于
      Kprobes for x86-64 may cause a kernel crash if it inserted on "iret"
      instruction. "call absolute" is invalid on x86-64, so we don't need
      treat it.
      
       - Change the processing order as same as x86-32.
       - Add "iret"(0xcf) case.
       - Remove next_rip local variable.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      0b0122fa
    • M
      x86: jprobe bugfix · 29b6cd79
      Masami Hiramatsu 提交于
      jprobe for x86-64 may cause kernel page fault when the jprobe_return()
      is called from incorrect function.
      
      - Use jprobe_saved_regs instead getting it from stack.
        (Especially on x86-64, it may get incorrect data, because
         pt_regs can not be get by using container_of(rsp))
      - Change the type of stack pointer to unsigned long *.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      29b6cd79
  3. 18 12月, 2007 1 次提交
  4. 07 12月, 2007 1 次提交
  5. 05 12月, 2007 3 次提交
  6. 04 12月, 2007 3 次提交
  7. 30 11月, 2007 1 次提交
    • J
      x86/paravirt: revert exports to restore old behaviour · f97b8954
      Jeremy Fitzhardinge 提交于
      Subdividing the paravirt_ops structure caused a regression in certain
      non-GPL modules which try to use mmu_ops and cpu_ops.  This restores the
      old behaviour, and makes it consistent with the non-CONFIG_PARAVIRT case.
      
      Takashi Iwai <tiwai@suse.de> adds:
      > I took at this problem (as I have an nvidia card on one of my
      > workstations), and found out that the following suffer from
      > EXPORT_SYMBOL_GPL changes:
      >
      > * local_disable_irq(), local_irq_save*(), etc.
      > * MSR-related macros like rdmsr(), wrmsr(), read_cr0(), etc.
      >   wbinvd(), too.
      > * pmd_val(), pgd_val(), etc are all involved with pv_mm_ops.
      >   pmd_large() and pmd_bad() is also indirectly involved.
      >   __flush_tlb() and friends suffer, too.
      
      Christoph Hellwig objects to this patch on the grounds that modules
      shouldn't be using these operations anyway.  I don't think this is a
      particularly good reason to reject the patch, for several reasons:
      
      1. These operations are still available to modules when not using
         CONFIG_PARAVIRT, since they are implicitly exported as inline
         functions via the kernel headers.  Exporting the same functionality as
         GPL-only symbols just adds a gratuitious difference between
         CONFIG_PARAVIRT and non-CONFIG_PARAVIRT configurations.  If we really
         think these operations are not for module use (or non-GPL module use),
         then we should solve the problem in a general way.
      
      2. It's a regression from previous kernels, which would work these
         modules even with CONFIG_PARAVIRT enabled.
      
      3. The operations in question seem pretty reasonable for modules to
         use.  The control registers/MSRs can be accessed directly anyway, so there's
         no benefit in preventing modules from using standard interfaces.  And it seems
         reasonable to allow a graphics driver to create its own mappings if it wants.
      
      Therefore, I think this patch should go in for 2.6.24.  If people
      really think that these operations should not be available to modules,
      then we can address that separately.
      Signed-off-by: NJeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
      Cc: Tobias Powalowski <t.powa@gmx.de>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Takashi Iwai <tiwai@suse.de>
      Cc: Zachary Amsden <zach@vmware.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f97b8954
  8. 27 11月, 2007 7 次提交
    • I
      x86: fix APIC related bootup crash on Athlon XP CPUs · f44d9efd
      Ingo Molnar 提交于
      warmbloodedcreature@gmail.com reported that an APIC-enabled
      Asus a7v8x-x with an Athlon XP reboots early in the bootup:
      
         http://bugzilla.kernel.org/show_bug.cgi?id=8723
      
      after a long marathon of spontaneous-reboot debugging, it turns
      out to be caused by sync_Arb_ids(). AMD CPUs never really needed
      this sequence anyway, so just return early if we meet an AMD CPU.
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      f44d9efd
    • T
      x86: export the symbol empty_zero_page on the 32-bit x86 architecture · 8232fd62
      Theodore Ts'o 提交于
      The latest KVM driver wants to use the empty_zero_page symbol, and it's
      not exported in 32-bit x86 (although it is exported by x86_64, s390, and
      uml architectures).
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      Cc: tglx@linutronix.de
      Cc: linux-kernel@vger.kernel.com
      Cc: kvm-devel@lists.sourceforge.net
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8232fd62
    • A
      x86: fix kprobes_64.c inlining borkage · 8645419c
      Andrew Morton 提交于
      fix:
      
      arch/x86/kernel/kprobes_64.c: In function 'set_current_kprobe':
      arch/x86/kernel/kprobes_64.c:152: sorry, unimplemented: inlining failed in call to 'is_IF_modifier': recursive inlining
      arch/x86/kernel/kprobes_64.c:166: sorry, unimplemented: called from here
      
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Cc: mingo@elte.hu
      Cc: akpm@linux-foundation.org
      Cc: tglx@linutronix.de
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8645419c
    • P
      lockdep: annotate do_debug() trap handler · 000f4a9e
      Peter Zijlstra 提交于
      Ensure the hardirq state is consistent before using locks. Use the rare
      trace_hardirqs_fixup() because the trap can happen in any context.
      
      resolves this rare lockdep warning:
      
      WARNING: at kernel/lockdep.c:2658 check_flags()
       [<c013571e>] check_flags+0x90/0x140
       [<c0138a69>] lock_release+0x4b/0x1d0
       [<c0507fea>] notifier_call_chain+0x2a/0x47
       [<c050806b>] __atomic_notifier_call_chain+0x64/0x6d
       [<c0508007>] __atomic_notifier_call_chain+0x0/0x6d
       [<c050808b>] atomic_notifier_call_chain+0x17/0x1a
       [<c0131802>] notify_die+0x30/0x34
       [<c0506b09>] do_debug+0x3e/0xd4
       [<c050658f>] debug_stack_correct+0x27/0x2c
       [<c04be389>] tcp_rcv_established+0x1/0x620
       [<c04c38c2>] tcp_v4_do_rcv+0x2b/0x313
       [<c04c56b6>] tcp_v4_rcv+0x467/0x85d
       [<c0505ff2>] _spin_lock_nested+0x27/0x32
       [<c04c5a4d>] tcp_v4_rcv+0x7fe/0x85d
       [<c04c560e>] tcp_v4_rcv+0x3bf/0x85d
       [<c04adbb5>] ip_local_deliver_finish+0x11b/0x1b0
       [<c04adac8>] ip_local_deliver_finish+0x2e/0x1b0
       [<c04ada7b>] ip_rcv_finish+0x27b/0x29a
       [<c04961e5>] netif_receive_skb+0xfb/0x2a6
       [<c04add0f>] ip_rcv+0x0/0x1fb
       [<c0496354>] netif_receive_skb+0x26a/0x2a6
       [<c04961e5>] netif_receive_skb+0xfb/0x2a6
       [<c049872e>] process_backlog+0x7f/0xc6
       [<c04983ba>] net_rx_action+0xb9/0x1ac
       [<c0498348>] net_rx_action+0x47/0x1ac
       [<c01376cb>] trace_hardirqs_on+0x118/0x16b
       [<c01225e2>] __do_softirq+0x49/0xa2
       [<c010595f>] do_softirq+0x60/0xdd
       [<c0506300>] _spin_unlock_irq+0x20/0x2c
       [<c0103e4f>] restore_nocheck+0x12/0x15
       [<c01440e1>] handle_fasteoi_irq+0x0/0x9b
       [<c0105a70>] do_IRQ+0x94/0xaa
       [<c0506300>] _spin_unlock_irq+0x20/0x2c
       [<c0104832>] common_interrupt+0x2e/0x34
       [<c0114703>] native_safe_halt+0x2/0x3
       [<c0102c01>] default_idle+0x44/0x65
       [<c010257f>] cpu_idle+0x42/0x50
       [<c076ea09>] start_kernel+0x26b/0x270
       [<c076e317>] unknown_bootoption+0x0/0x196
       =======================
      irq event stamp: 559190
      hardirqs last  enabled at (559190): [<c0507316>] kprobe_exceptions_notify+0x299/0x305
      hardirqs last disabled at (559189): [<c05067bf>] do_int3+0x1d/0x95
      softirqs last  enabled at (559172): [<c010595f>] do_softirq+0x60/0xdd
      softirqs last disabled at (559181): [<c010595f>] do_softirq+0x60/0xdd
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      000f4a9e
    • I
      x86: turn off iommu merge by default · bc84cf17
      Ingo Molnar 提交于
      revert this commit for now:
      
          commit 94806268
          Author: Andi Kleen <ak@suse.de>
          Date:   Fri Oct 19 20:35:03 2007 +0200
      
              x86: enable iommu_merge by default
      
      it's causing regressions:
      
          http://bugzilla.kernel.org/show_bug.cgi?id=9412Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      bc84cf17
    • A
      x86: printk kernel version in WARN_ON and other dump_stack users · 57c351de
      Arjan van de Ven 提交于
      today, all oopses contain a version number of the kernel, which is nice
      because the people who actually do bother to read the oops get this
      vital bit of information always without having to ask the reporter in
      another round trip.
      
      However, WARN_ON() and many other dump_stack() users right now lack this
      information; the patch below adds this. This information is essential
      for getting people to use their time effectively when looking at these
      things; in addition, it's essential for tools that try to collect
      statistics about defects.
      
      Please consider, since its so simple and important for long term kernel
      quality processes.
      
      The code is identical between 32/64 bit; a lot of this code should be
      unified over time, the patch keeps the identical-ness intact.
      Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      57c351de
    • M
      x86: fix NMI watchdog & 'stopped time' problem · d4d25dec
      Maciej W. Rozycki 提交于
      More than 3 years ago Niclas Gustafsson reported a 'stopped time'
      problem:
      
      > Watching the /proc/interrupts with 10s apart after the "stop".
      >
      > [root@s151 root]# more /proc/interrupts
      >            CPU0
      >   0:   66413955  local-APIC-edge  timer
      [...]
      > LOC:   67355837
      > ERR:          0
      > MIS:          0
      > [root@s151 root]# more /proc/interrupts
      >            CPU0
      >   0:   66413955  local-APIC-edge  timer
      [...]
      > LOC:   67379568
      > ERR:          0
      > MIS:          0
      
      This may be because buggy SMM firmware messes with the 8259A (configured
      for a transparent mode -- yes that rare "local-APIC-edge" mode is tricky
      ;-) ) insanely.
      
      this should resolve:
      
        http://bugzilla.kernel.org/show_bug.cgi?id=2544
        http://bugzilla.kernel.org/show_bug.cgi?id=6296Patch-dusted-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      d4d25dec
  9. 20 11月, 2007 1 次提交
  10. 17 11月, 2007 9 次提交
  11. 15 11月, 2007 1 次提交
    • A
      x86: don't call mce_create_device on CPU_UP_PREPARE · bae19fe0
      Andreas Herrmann 提交于
      Fix regression introduced with d435d862
      ("cpu hotplug: mce: fix cpu hotplug error handling").
      
      A CPU which was not brought up during boot (using maxcpus and
      additional_cpus parameters) couldn't be onlined anymore.  For such a CPU it
      seemed that MCE was not supported during CPU_UP_PREPARE-time which caused
      mce_cpu_callback to return NOTIFY_BAD to notifier_call_chain.  To fix this
      we:
      
       - call mce_create_device for CPU_ONLINE event (instead of CPU_UP_PREPARE),
       - avoid mce_remove_device() for the CPU that is not correctly initialized
         by mce_create_device() failure,
       - make mce_cpu_callback always return NOTIFY_OK for CPU_ONLINE event.
         Because CPU_ONLINE callback return value is always ignored.
      
      [akinobu.mita@gmail.com: avoid mce_remove_device() for not initialized device]
      [akinobu.mita@gmail.com: make mce_cpu_callback always return NOTIFY_OK]
      Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
      Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bae19fe0
  12. 13 11月, 2007 3 次提交
  13. 10 11月, 2007 2 次提交
  14. 30 10月, 2007 1 次提交