1. 14 3月, 2012 1 次提交
  2. 26 12月, 2011 1 次提交
    • J
      KVM: Don't automatically expose the TSC deadline timer in cpuid · 4d25a066
      Jan Kiszka 提交于
      Unlike all of the other cpuid bits, the TSC deadline timer bit is set
      unconditionally, regardless of what userspace wants.
      
      This is broken in several ways:
       - if userspace doesn't use KVM_CREATE_IRQCHIP, and doesn't emulate the TSC
         deadline timer feature, a guest that uses the feature will break
       - live migration to older host kernels that don't support the TSC deadline
         timer will cause the feature to be pulled from under the guest's feet;
         breaking it
       - guests that are broken wrt the feature will fail.
      
      Fix by not enabling the feature automatically; instead report it to userspace.
      Because the feature depends on KVM_CREATE_IRQCHIP, which we cannot guarantee
      will be called, we expose it via a KVM_CAP_TSC_DEADLINE_TIMER and not
      KVM_GET_SUPPORTED_CPUID.
      
      Fixes the Illumos guest kernel, which uses the TSC deadline timer feature.
      
      [avi: add the KVM_CAP + documentation]
      Reported-by: NAlexey Zaytsev <alexey.zaytsev@gmail.com>
      Tested-by: NAlexey Zaytsev <alexey.zaytsev@gmail.com>
      Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
      Signed-off-by: NAvi Kivity <avi@redhat.com>
      4d25a066
  3. 25 12月, 2011 1 次提交
    • J
      KVM: x86: Prevent starting PIT timers in the absence of irqchip support · 0924ab2c
      Jan Kiszka 提交于
      User space may create the PIT and forgets about setting up the irqchips.
      In that case, firing PIT IRQs will crash the host:
      
      BUG: unable to handle kernel NULL pointer dereference at 0000000000000128
      IP: [<ffffffffa10f6280>] kvm_set_irq+0x30/0x170 [kvm]
      ...
      Call Trace:
       [<ffffffffa11228c1>] pit_do_work+0x51/0xd0 [kvm]
       [<ffffffff81071431>] process_one_work+0x111/0x4d0
       [<ffffffff81071bb2>] worker_thread+0x152/0x340
       [<ffffffff81075c8e>] kthread+0x7e/0x90
       [<ffffffff815a4474>] kernel_thread_helper+0x4/0x10
      
      Prevent this by checking the irqchip mode before starting a timer. We
      can't deny creating the PIT if the irqchips aren't set up yet as
      current user land expects this order to work.
      Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
      Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
      0924ab2c
  4. 24 12月, 2011 1 次提交
  5. 20 12月, 2011 2 次提交
  6. 16 12月, 2011 1 次提交
    • I
      xen: only limit memory map to maximum reservation for domain 0. · d3db7281
      Ian Campbell 提交于
      d312ae87 "xen: use maximum reservation to limit amount of usable RAM"
      clamped the total amount of RAM to the current maximum reservation. This is
      correct for dom0 but is not correct for guest domains. In order to boot a guest
      "pre-ballooned" (e.g. with memory=1G but maxmem=2G) in order to allow for
      future memory expansion the guest must derive max_pfn from the e820 provided by
      the toolstack and not the current maximum reservation (which can reflect only
      the current maximum, not the guest lifetime max). The existing algorithm
      already behaves this correctly if we do not artificially limit the maximum
      number of pages for the guest case.
      
      For a guest booted with maxmem=512, memory=128 this results in:
       [    0.000000] BIOS-provided physical RAM map:
       [    0.000000]  Xen: 0000000000000000 - 00000000000a0000 (usable)
       [    0.000000]  Xen: 00000000000a0000 - 0000000000100000 (reserved)
      -[    0.000000]  Xen: 0000000000100000 - 0000000008100000 (usable)
      -[    0.000000]  Xen: 0000000008100000 - 0000000020800000 (unusable)
      +[    0.000000]  Xen: 0000000000100000 - 0000000020800000 (usable)
      ...
       [    0.000000] NX (Execute Disable) protection: active
       [    0.000000] DMI not present or invalid.
       [    0.000000] e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
       [    0.000000] e820 remove range: 00000000000a0000 - 0000000000100000 (usable)
      -[    0.000000] last_pfn = 0x8100 max_arch_pfn = 0x1000000
      +[    0.000000] last_pfn = 0x20800 max_arch_pfn = 0x1000000
       [    0.000000] initial memory mapped : 0 - 027ff000
       [    0.000000] Base memory trampoline at [c009f000] 9f000 size 4096
      -[    0.000000] init_memory_mapping: 0000000000000000-0000000008100000
      -[    0.000000]  0000000000 - 0008100000 page 4k
      -[    0.000000] kernel direct mapping tables up to 8100000 @ 27bb000-27ff000
      +[    0.000000] init_memory_mapping: 0000000000000000-0000000020800000
      +[    0.000000]  0000000000 - 0020800000 page 4k
      +[    0.000000] kernel direct mapping tables up to 20800000 @ 26f8000-27ff000
       [    0.000000] xen: setting RW the range 27e8000 - 27ff000
       [    0.000000] 0MB HIGHMEM available.
      -[    0.000000] 129MB LOWMEM available.
      -[    0.000000]   mapped low ram: 0 - 08100000
      -[    0.000000]   low ram: 0 - 08100000
      +[    0.000000] 520MB LOWMEM available.
      +[    0.000000]   mapped low ram: 0 - 20800000
      +[    0.000000]   low ram: 0 - 20800000
      
      With this change "xl mem-set <domain> 512M" will successfully increase the
      guest RAM (by reducing the balloon).
      
      There is no change for dom0.
      Reported-and-Tested-by: NGeorge Shuklin <george.shuklin@gmail.com>
      Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
      Cc: stable@kernel.org
      Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      d3db7281
  7. 13 12月, 2011 1 次提交
  8. 10 12月, 2011 1 次提交
    • M
      x86, efi: Make efi_call_phys_{prelog,epilog} CONFIG_RELOCATABLE-aware · 6d3e32e6
      Matt Fleming 提交于
      efi_call_phys_prelog() sets up a 1:1 mapping of the physical address
      range in swapper_pg_dir. Instead of replacing then restoring entries
      in swapper_pg_dir we should be using initial_page_table which already
      contains the 1:1 mapping.
      
      It's safe to blindly switch back to swapper_pg_dir in the epilog
      because the physical EFI routines are only called before
      efi_enter_virtual_mode(), e.g. before any user processes have been
      forked. Therefore, we don't need to track which pgd was in %cr3 when
      we entered the prelog.
      
      The previous code actually contained a bug because it assumed that the
      kernel was loaded at a physical address within the first 8MB of ram,
      usually at 0x100000. However, this isn't the case with a
      CONFIG_RELOCATABLE=y kernel which could have been loaded anywhere in
      the physical address space.
      
      Also delete the ancient (and bogus) comments about the page table
      being restored after the lock is released. There is no locking.
      
      Cc: Matthew Garrett <mjg@redhat.com>
      Cc: Darrent Hart <dvhart@linux.intel.com>
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Link: http://lkml.kernel.org/r/1323346250.3894.74.camel@mfleming-mobl1.ger.corp.intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      6d3e32e6
  9. 09 12月, 2011 3 次提交
    • Y
      thp: add compound tail page _mapcount when mapped · b6999b19
      Youquan Song 提交于
      With the 3.2-rc kernel, IOMMU 2M pages in KVM works.  But when I tried
      to use IOMMU 1GB pages in KVM, I encountered an oops and the 1GB page
      failed to be used.
      
      The root cause is that 1GB page allocation calls gup_huge_pud() while 2M
      page calls gup_huge_pmd.  If compound pages are used and the page is a
      tail page, gup_huge_pmd() increases _mapcount to record tail page are
      mapped while gup_huge_pud does not do that.
      
      So when the mapped page is relesed, it will result in kernel oops
      because the page is not marked mapped.
      
      This patch add tail process for compound page in 1GB huge page which
      keeps the same process as 2M page.
      
      Reproduce like:
      1. Add grub boot option: hugepagesz=1G hugepages=8
      2. mount -t hugetlbfs -o pagesize=1G hugetlbfs /dev/hugepages
      3. qemu-kvm -m 2048 -hda os-kvm.img -cpu kvm64 -smp 4 -mem-path /dev/hugepages
      	-net none -device pci-assign,host=07:00.1
      
        kernel BUG at mm/swap.c:114!
        invalid opcode: 0000 [#1] SMP
        Call Trace:
          put_page+0x15/0x37
          kvm_release_pfn_clean+0x31/0x36
          kvm_iommu_put_pages+0x94/0xb1
          kvm_iommu_unmap_memslots+0x80/0xb6
          kvm_assign_device+0xba/0x117
          kvm_vm_ioctl_assigned_device+0x301/0xa47
          kvm_vm_ioctl+0x36c/0x3a2
          do_vfs_ioctl+0x49e/0x4e4
          sys_ioctl+0x5a/0x7c
          system_call_fastpath+0x16/0x1b
        RIP  put_compound_page+0xd4/0x168
      Signed-off-by: NYouquan Song <youquan.song@intel.com>
      Reviewed-by: NAndrea Arcangeli <aarcange@redhat.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b6999b19
    • M
      x86, efi: Calling __pa() with an ioremap()ed address is invalid · e8c71062
      Matt Fleming 提交于
      If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set
      in ->attribute we currently call set_memory_uc(), which in turn
      calls __pa() on a potentially ioremap'd address.
      
      On CONFIG_X86_32 this is invalid, resulting in the following
      oops on some machines:
      
        BUG: unable to handle kernel paging request at f7f22280
        IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
        [...]
      
        Call Trace:
         [<c104f8ca>] ? page_is_ram+0x1a/0x40
         [<c1025aff>] reserve_memtype+0xdf/0x2f0
         [<c1024dc9>] set_memory_uc+0x49/0xa0
         [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa
         [<c19216d4>] start_kernel+0x291/0x2f2
         [<c19211c7>] ? loglevel+0x1b/0x1b
         [<c19210bf>] i386_start_kernel+0xbf/0xc8
      
      A better approach to this problem is to map the memory region
      with the correct attributes from the start, instead of modifying
      it after the fact. The uncached case can be handled by
      ioremap_nocache() and the cached by ioremap_cache().
      
      Despite first impressions, it's not possible to use
      ioremap_cache() to map all cached memory regions on
      CONFIG_X86_64 because EFI_RUNTIME_SERVICES_DATA regions really
      don't like being mapped into the vmalloc space, as detailed in
      the following bug report,
      
      	https://bugzilla.redhat.com/show_bug.cgi?id=748516
      
      Therefore, we need to ensure that any EFI_RUNTIME_SERVICES_DATA
      regions are covered by the direct kernel mapping table on
      CONFIG_X86_64. To accomplish this we now map E820_RESERVED_EFI
      regions via the direct kernel mapping with the initial call to
      init_memory_mapping() in setup_arch(), whereas previously these
      regions wouldn't be mapped if they were after the last E820_RAM
      region until efi_ioremap() was called. Doing it this way allows
      us to delete efi_ioremap() completely.
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Matthew Garrett <mjg@redhat.com>
      Cc: Zhang Rui <rui.zhang@intel.com>
      Cc: Huang Ying <huang.ying.caritas@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console-pimps.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      e8c71062
    • M
      x86, hpet: Immediately disable HPET timer 1 if rtc irq is masked · 2ded6e6a
      Mark Langsdorf 提交于
      When HPET is operating in RTC mode, the TN_ENABLE bit on timer1
      controls whether the HPET or the RTC delivers interrupts to irq8. When
      the system goes into suspend, the RTC driver sends a signal to the
      HPET driver so that the HPET releases control of irq8, allowing the
      RTC to wake the system from suspend. The switchover is accomplished by
      a write to the HPET configuration registers which currently only
      occurs while servicing the HPET interrupt.
      
      On some systems, I have seen the system suspend before an HPET
      interrupt occurs, preventing the write to the HPET configuration
      register and leaving the HPET in control of the irq8. As the HPET is
      not active during suspend, it does not generate a wake signal and RTC
      alarms do not work.
      
      This patch forces the HPET driver to immediately transfer control of
      the irq8 channel to the RTC instead of waiting until the next
      interrupt event.
      Signed-off-by: NMark Langsdorf <mark.langsdorf@amd.com>
      Link: http://lkml.kernel.org/r/20111118153306.GB16319@alberich.amd.comTested-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
      Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: stable@vger.kernel.org
      2ded6e6a
  10. 06 12月, 2011 5 次提交
  11. 05 12月, 2011 15 次提交
  12. 04 12月, 2011 1 次提交
    • K
      xen/pm_idle: Make pm_idle be default_idle under Xen. · e5fd47bf
      Konrad Rzeszutek Wilk 提交于
      The idea behind commit d91ee586 ("cpuidle: replace xen access to x86
      pm_idle and default_idle") was to have one call - disable_cpuidle()
      which would make pm_idle not be molested by other code.  It disallows
      cpuidle_idle_call to be set to pm_idle (which is excellent).
      
      But in the select_idle_routine() and idle_setup(), the pm_idle can still
      be set to either: amd_e400_idle, mwait_idle or default_idle.  This
      depends on some CPU flags (MWAIT) and in AMD case on the type of CPU.
      
      In case of mwait_idle we can hit some instances where the hypervisor
      (Amazon EC2 specifically) sets the MWAIT and we get:
      
        Brought up 2 CPUs
        invalid opcode: 0000 [#1] SMP
      
        Pid: 0, comm: swapper Not tainted 3.1.0-0.rc6.git0.3.fc16.x86_64 #1
        RIP: e030:[<ffffffff81015d1d>]  [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
        ...
        Call Trace:
         [<ffffffff8100e2ed>] cpu_idle+0xae/0xe8
         [<ffffffff8149ee78>] cpu_bringup_and_idle+0xe/0x10
        RIP  [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
         RSP <ffff8801d28ddf10>
      
      In the case of amd_e400_idle we don't get so spectacular crashes, but we
      do end up making an MSR which is trapped in the hypervisor, and then
      follow it up with a yield hypercall.  Meaning we end up going to
      hypervisor twice instead of just once.
      
      The previous behavior before v3.0 was that pm_idle was set to
      default_idle regardless of select_idle_routine/idle_setup.
      
      We want to do that, but only for one specific case: Xen.  This patch
      does that.
      
      Fixes RH BZ #739499 and Ubuntu #881076
      Reported-by: NStefan Bader <stefan.bader@canonical.com>
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e5fd47bf
  13. 22 11月, 2011 1 次提交
  14. 20 11月, 2011 1 次提交
  15. 17 11月, 2011 5 次提交