1. 25 Jun, 2005 40 commits
    • Heiko Carstens's avatar
      [PATCH] kexec: s390 support · cf13f0ea
      Heiko Carstens authored
      
      
      Add kexec support for s390 architecture.
      
      From: Milton Miller <miltonm@bga.com>
      
      - Fix passing of first argument to relocate_kernel assembly.
      - Fix Kconfig description.
      - Remove wrong comment and comments that describe obvious things.
      - Allow only KEXEC_TYPE_DEFAULT as image type -> dump not supported.
      Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      cf13f0ea
    • R Sharada's avatar
      [PATCH] ppc64: kexec support for ppc64 · fce0d574
      R Sharada authored
      
      
      This patch implements the kexec support for ppc64 platforms.
      
      A couple of notes:
      
      1)  We copy the pages in virtual mode, using the full base kernel
          and a statically allocated stack.   At kexec_prepare time we
          scan the pages and if any overlap our (0, _end[]) range we
          return -ETXTBSY.
      
          On PowerPC 64 systems running in LPAR (logical partitioning)
          mode, only a small region of memory, referred to as the RMO,
          can be accessed in real mode.  Since Linux runs with only one
          zone of memory in the memory allocator, and it can be orders of
          magnitude more memory than the RMO, looping until we allocate
          pages in the source region is not feasible.  Copying in virtual
          means we don't have to write a hash table generation and call
          hypervisor to insert translations, instead we rely on the pinned
          kernel linear mapping.  The kernel already has move to linked
          location built in, so there is no requirement to load it at 0.
      
          If we want to load something other than a kernel, then a stub
          can be written to copy a linear chunk in real mode.
      
      2)  The start entry point gets passed parameters from the kernel.
          Slaves are started at a fixed address after copying code from
          the entry point.
      
          All CPUs get passed their firmware assigned physical id in r3
          (most calling conventions use this register for the first
          argument).
      
          This is used to distinguish each CPU from all other CPUs.
          Since firmware is not around, there is no other way to obtain
          this information other than to pass it somewhere.
      
          A single CPU, referred to here as the master and the one executing
          the kexec call, branches to start with the address of start in r4.
          While this can be calculated, we have to load it through a gpr to
          branch to this point so defining the register this is contained
          in is free.  A stack of unspecified size is available at r1
          (also common calling convention).
      
          All remaining running CPUs are sent to start at absolute address
          0x60 after copying the first 0x100 bytes from start to address 0.
          This convention was chosen because it matches what the kernel
          has been doing itself.  (only gpr3 is defined).
      
          Note: This is not quite the convention of the kexec bootblock v2
          in the kernel.  A stub has been written to convert between them,
          and we may adjust the kernel in the future to allow this directly
          without any stub.
      
      3)  Destination pages can be placed anywhere, even where they
          would not be accessible in real mode.  This will allow us to
          place ram disks above the RMO if we choose.
      Signed-off-by: default avatarMilton Miller <miltonm@bga.com>
      Signed-off-by: default avatarR Sharada <sharada@in.ibm.com>
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      fce0d574
    • R Sharada's avatar
      [PATCH] ppc64 kexec: native hash clear · f4c82d51
      R Sharada authored
      
      
      Add code to clear the hash table and invalidate the tlb for native (SMP,
      non-LPAR) mode.  Supports 16M and 4k pages.
      Signed-off-by: default avatarMilton Miller <miltonm@bga.com>
      Signed-off-by: default avatarR Sharada <sharada@in.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      f4c82d51
    • Eric W. Biederman's avatar
      [PATCH] kexec: kexec ppc support · 70765aa4
      Eric W. Biederman authored
      
      
      I have tweaked this patch slightly to handle an empty list
      of pages to relocate passed to relocate_new_kernel.  And
      I have added ppc_md.machine_crash_shutdown.  To keep up with
      the changes in the generic kexec infrastructure.
      
      From: Albert Herranz <albert_herranz@yahoo.es>
      
      The following patch adds support for kexec on the ppc32 platform.
      
      Non-OpenFirmware based platforms are likely to work directly without
      additional changes on the kernel side.  The kexec-tools userland package
      may need to be slightly updated, though.
      
      For OpenFirmware based machines, additional work is still needed on the
      kernel side before kexec support is ready.  Benjamin Herrenschmidt is
      kindly working on that part.
      
      In order for a ppc platform to use the kexec kernel services it must
      implement some ppc_md hooks.  Otherwise, kexec will be explicitly disabled,
      as suggested by benh.
      
      There are 3+1 new ppc_md hooks that a platform supporting kexec may
      implement.  Two of them are mandatory for kexec to work.  See
      include/asm-ppc/machdep.h for details.
      
      - machine_kexec_prepare(image)
      
        This function is called to make any arrangements to the image before it
        is loaded.
      
        This hook _MUST_ be provided by a platform in order to activate kexec
        support for that platform.  Otherwise, the platform is considered to not
        support kexec and the kexec_load system call will fail (that makes all
        existing platforms by default non-kexec'able).
      
      - machine_kexec_cleanup(image)
      
        This function is called to make any cleanups on image after the loaded
        image data it is freed.  This hook is optional.  A platform may or may
        not provide this hook.
      
      - machine_kexec(image)
      
        This function is called to perform the _actual_ kexec.  This hook
        _MUST_ be provided by a platform in order to activate kexec support for
        that platform.
      
        If a platform provides machine_kexec_prepare but forgets to provide
        machine_kexec, a kexec will fall back to a reboot.
      
        A ready-to-use machine_kexec_simple() generic function is provided to,
        hopefully, simplify kexec adoption for embedded platforms.  A platform
        may call this function from its specific machine_kexec hook, like this:
      
      void myplatform_kexec(struct kimage *image)
      {
              machine_kexec_simple(image);
      }
      
      - machine_shutdown()
      
        This function is called to perform any machine specific shutdowns, not
        already done by drivers.  This hook is optional.  A platform may or may
        not provide this hook.
      
      An example (trimmed) platform specific module for a platform supporting
      kexec through the existing machine_kexec_simple follows:
      
      /* ... */
      
      #ifdef CONFIG_KEXEC
      int myplatform_kexec_prepare(struct kimage *image)
      {
              /* here, we can place additional preparations
      */
              return 0; /* yes, we support kexec */
      }
      
      void myplatform_kexec(struct kimage *image)
      {
              machine_kexec_simple(image);
      }
      #endif /* CONFIG_KEXEC */
      
      /* ... */
      
      void __init
      platform_init(unsigned long r3, unsigned long r4,
      unsigned long r5,
                    unsigned long r6, unsigned long r7)
      {
      
      /* ... */
      
      #ifdef CONFIG_KEXEC
              ppc_md.machine_kexec_prepare =
      myplatform_kexec_prepare;
              ppc_md.machine_kexec         =
      myplatform_kexec;
      #endif /* CONFIG_KEXEC */
      
      /* ... */
      
      }
      
      The kexec ppc kernel support has been heavily tested on the GameCube Linux
      port, and, as reported in the fastboot mailing list, it has been tested too
      on a Moto 82xx ppc by Rick Richardson.
      Signed-off-by: default avatarAlbert Herranz <albert_herranz@yahoo.es>
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      70765aa4
    • Eric W. Biederman's avatar
      [PATCH] crashdump: x86_64: crashkernel option · 5f5609df
      Eric W. Biederman authored
      
      
      This is the x86_64 implementation of the crashkernel option.  It reserves
      a window of memory very early in the bootup process, so we never use
      it for anything but the kernel to switch to when the running
      kernel panics.
      
      In addition to reserving this memory a resource structure is registered
      so looking at /proc/iomem it is clear what happened to that memory.
      
      ISSUES:
      Is it possible to implement this in a architecture generic way?
      What should be done with architectures that always use an iommu and
      thus don't report their RAM memory resources in /proc/iomem?
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5f5609df
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64 kexec implementation · 5234f5eb
      Eric W. Biederman authored
      
      
      This is the x86_64 implementation of machine kexec.  32bit compatibility
      support has been implemented, and machine_kexec has been enhanced to not care
      about the changing internal kernel paget table structures.
      
      From: Alexander Nyberg <alexn@dsv.su.se>
      
            build fix
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5234f5eb
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: factor out apic shutdown code · d8955958
      Eric W. Biederman authored
      
      
      Factor out the apic and smp shutdown code from machine_restart so it can be
      called by in the kexec reboot path as well.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      d8955958
    • Eric W. Biederman's avatar
      [PATCH] crashdump: x86 crashkernel option · 1bc3b91a
      Eric W. Biederman authored
      
      
      This is the x86 implementation of the crashkernel option.  It reserves a
      window of memory very early in the bootup process, so we never use it for
      anything but the kernel to switch to when the running kernel panics.
      
      In addition to reserving this memory a resource structure is registered so
      looking at /proc/iomem it is clear what happened to that memory.
      
      ISSUES:
      Is it possible to implement this in a architecture generic way?
      What should be done with architectures that always use an iommu and
      thus don't report their RAM memory resources in /proc/iomem?
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      1bc3b91a
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86 shutdown APICs during crash_shutdown · 63d30298
      Eric W. Biederman authored
      
      
      In the case of a crash/panic an architecture specific function
      machine_crash_shutdown is called.  This patch adds to the x86 machine_crash
      function the standard kernel code for shutting down apics.
      
      Every line of code added to that function increases the risk that we will call
      code after a kernel panic that is not safe.
      
      This patch should not make it to the stable kernel without a being reviewed a
      lot more.  It is unclear how much a hardned kernel can take when it comes to
      misconfigured apics.  So since a normal kernel has problems this patch does a
      clean shutdown.
      
      It is my expectation this patch will be dropped from future generations of the
      kexec work.  But for the moment it is a crutch to keep from breaking
      everything.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      63d30298
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: snapshot registers during crash shutdown · 2c818b45
      Eric W. Biederman authored
      
      
      After the kernel panics if we wish to generate an entire machine core file it
      is very nice to know the register state at the time the machine crashed.
      
      After long discussion it was realized that if you are going to be saving the
      information anyway it is reasonable to store the information in a format that
      it will be used and recognized in so the register state is stored in the
      standard ELF note format.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      2c818b45
    • Eric W. Biederman's avatar
      [PATCH] crashdump: x86: add NMI handler to capture other CPUs · c4ac4263
      Eric W. Biederman authored
      
      
      One of the dangers when switching from one kernel to another is what happens
      to all of the other cpus that were running in the crashed kernel.  In an
      attempt to avoid that problem this patch adds a nmi handler and attempts to
      shoot down the other cpus by sending them non maskable interrupts.
      
      The code then waits for 1 second or until all known cpus have stopped running
      and then jumps from the running kernel that has crashed to the kernel in
      reserved memory.
      
      The kernel spin loop is used for the delay as that should behave continue to
      be safe even in after a crash.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      c4ac4263
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86 kexec core · 5033cba0
      Eric W. Biederman authored
      
      
      This is the i386 implementation of kexec.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5033cba0
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: factor out apic shutdown code · dd2a1305
      Eric W. Biederman authored
      
      
      Factor out the apic and smp shutdown code from machine_restart so it can be
      called by in the kexec reboot path as well.
      
      By switching to the bootstrap cpu by default on reboot I can delete/simplify
      some motherboard fixups well.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      dd2a1305
    • Vivek Goyal's avatar
      [PATCH] Kexec on panic vmlinux initrd fix · 50cccc69
      Vivek Goyal authored
      
      
      This is a minor bug fix in kexec to resolve the problem of loading panic
      kernel with initrd.
      
      o Problem: Loading a capture kenrel fails if initrd is also being loaded.
        This has been observed for vmlinux image for kexec on panic case.
      
      o This patch fixes the problem. In segment location and size verification
        logic, minor correction has been done. Segment memory end (mend) should be
        mstart + memsz - 1. This one byte offset was source of failure for initrd
        loading which was being loaded at hole boundary.
      Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      50cccc69
    • Eric W. Biederman's avatar
      [PATCH] kexec: add kexec syscalls · dc009d92
      Eric W. Biederman authored
      
      
      This patch introduces the architecture independent implementation the
      sys_kexec_load, the compat_sys_kexec_load system calls.
      
      Kexec on panic support has been integrated into the core patch and is
      relatively clean.
      
      In addition the hopefully architecture independent option
      crashkernel=size@location has been docuemented.  It's purpose is to reserve
      space for the panic kernel to live, and where no DMA transfer will ever be
      setup to access.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAlexander Nyberg <alexn@telia.com>
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      dc009d92
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: add CONFIG_PHYSICAL_START · d0537508
      Eric W. Biederman authored
      
      
      For one kernel to report a crash another kernel has created we need
      to have 2 kernels loaded simultaneously in memory.  To accomplish this
      the two kernels need to built to run at different physical addresses.
      
      This patch adds the CONFIG_PHYSICAL_START option to the x86_64 kernel
      so we can do just that.  You need to know what you are doing and
      the ramifications are before changing this value, and most users
      won't care so I have made it depend on CONFIG_EMBEDDED
      
      bzImage kernels will work and run at a different address when compiled
      with this option but they will still load at 1MB.  If you need a kernel
      loaded at a different address as well you need to boot a vmlinux.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      d0537508
    • Vivek Goyal's avatar
      [PATCH] kexec: reserve Bootmem fix for booting nondefault location kernel · 8a919085
      Vivek Goyal authored
      
      
      This patch fixes a problem with reserving memory during boot up of a kernel
      built for non-default location.  Currently boot memory allocator reserves
      the memory required by kernel image, boot allocaotor bitmap etc.  It
      assumes that kernel is loaded at 1MB (HIGH_MEMORY hard coded to 1024*1024).
       But kernel can be built for non-default locatoin, hence existing
      hardcoding will lead to reserving unnecessary memory.  This patch fixes it.
      Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      8a919085
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: add CONFIG_PYSICAL_START · 3d345e3f
      Eric W. Biederman authored
      
      
      For one kernel to report a crash another kernel has created we need
      to have 2 kernels loaded simultaneously in memory.  To accomplish this
      the two kernels need to built to run at different physical addresses.
      
      This patch adds the CONFIG_PHYSICAL_START option to the x86 kernel
      so we can do just that.  You need to know what you are doing and
      the ramifications are before changing this value, and most users
      won't care so I have made it depend on CONFIG_EMBEDDED
      
      bzImage kernels will work and run at a different address when compiled
      with this option but they will still load at 1MB.  If you need a kernel
      loaded at a different address as well you need to boot a vmlinux.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      3d345e3f
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: vmlinux: fix physical addresses · 5ded01e8
      Eric W. Biederman authored
      
      
      The vmlinux on x86_64 does not report the correct physical address of
      the kernel.  Instead in the physical address field it currently
      reports the virtual address of the kernel.
      
      This is patch is a bug fix that corrects vmlinux to report the
      proper physical addresses.
      
      This is potentially a help for crash dump analysis tools.
      
      This definitiely allows bootloaders that load vmlinux as a standard
      ELF executable.  Bootloaders directly loading vmlinux become of
      practical importance when we consider the kexec on panic case.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5ded01e8
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: vmlinux: fix physical addresses · ad0d75eb
      Eric W. Biederman authored
      
      
      The vmlinux on i386 does not report the correct physical address of
      the kernel.  Instead in the physical address field it currently
      reports the virtual address of the kernel.
      
      This is patch is a bug fix that corrects vmlinux to report the
      proper physical addresses.
      
      This is potentially a help for crash dump analysis tools.
      
      This definitiely allows bootloaders that load vmlinux as a standard
      ELF executable.  Bootloaders directly loading vmlinux become of
      practical importance when we consider the kexec on panic case.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      ad0d75eb
    • Eric W. Biederman's avatar
      [PATCH] kexec: vmlinux: fix physical addresses · 60bad7fa
      Eric W. Biederman authored
      
      
      In vmlinux.lds.h the code is carefull to define every section so vmlinux
      properly reports the correct physical load address of code, as well as
      it's virtual address.
      
      The new SECURITY_INIT definition fails to follow that convention and
      and causes incorrect physical address to appear in the vmlinux if
      there are any security initcalls.
      
      This patch updates the SECURITY_INIT to follow the convention in the rest of
      the file.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      60bad7fa
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: restore apic virtual wire mode on shutdown · 208fb931
      Eric W. Biederman authored
      
      
      When coming out of apic mode attempt to set the appropriate
      apic back into virtual wire mode.  This improves on previous versions
      of this patch by by never setting bot the local apic and the ioapic
      into veritual wire mode.
      
      This code looks at data from the mptable to see if an ioapic has
      an ExtInt input to make this decision.  A future improvement
      is to figure out which apic or ioapic was in virtual wire mode
      at boot time and to remember it.  That is potentially a more accurate
      method, of selecting which apic to place in virutal wire mode.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      208fb931
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: resture apic virtual wire mode on shutdown · 650927ef
      Eric W. Biederman authored
      
      
      When coming out of apic mode attempt to set the appropriate
      apic back into virtual wire mode.  This improves on previous versions
      of this patch by by never setting bot the local apic and the ioapic
      into veritual wire mode.
      
      This code looks at data from the mptable to see if an ioapic has
      an ExtInt input to make this decision.  A future improvement
      is to figure out which apic or ioapic was in virtual wire mode
      at boot time and to remember it.  That is potentially a more accurate
      method, of selecting which apic to place in virutal wire mode.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      650927ef
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: add i8259 shutdown method · 719e7110
      Eric W. Biederman authored
      
      
      From: Eric W. Biederman <ebiederm@xmission.com
      
      The following patch simply adds a shutdown method to the x86_64 i8259 code.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      719e7110
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: i8259 shutdown: disable interrupts · cee5dab4
      Eric W. Biederman authored
      From: Eric W. Biederman <ebiederm@xmission.com>
      
      This patch disables interrupt generation from the legacy pic on reboot.  Now
      that there is a sys_device class it should not be called while drivers are
      still using interrupts.
      
      There is a report about this breaking ACPI power off on some systems.
      http://bugme.osdl.org/show_bug.cgi?id=4041
      
      
      However the final comment seems to exonerate this code.  So until
      I get more information I believe that was a false positive.
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      cee5dab4
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86_64: e820 64bit fix · 70adada4
      Eric W. Biederman authored
      
      
      From: Eric W. Biederman <ebiederm@xmission.com>
      
      It is ok to reserve resources > 4G on x86_64 struct resource is 64bit now :)
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      70adada4
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: local apic fix · 9635b47d
      Eric W. Biederman authored
      
      
      From: "Maciej W. Rozycki" <macro@linux-mips.org>
      
      Fix a kexec problem whcih causes local APIC detection failure.
      
      The problem is detect_init_APIC() is called early, before the command line
      have been processed.  Therefore "lapic" (and "nolapic") have not been seen,
      yet.
      Signed-off-by: default avatarMaciej W. Rozycki <macro@linux-mips.org>
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      9635b47d
    • Eric W. Biederman's avatar
      [PATCH] kexec: x86: rename APIC_MODE_EXINT · 8f43d03f
      Eric W. Biederman authored
      
      
      From: "Maciej W. Rozycki" <macro@linux-mips.org>
      
      Rename APIC_MODE_EXINT to APIC_MODE_EXTINT - I think it should be named
      after what the mode is called in documentation.
      
      From: "Eric W. Biederman" <ebiederm@lnxi.com>
      
      I have reduced this patch to just the name change in the header.  And
      integrated the changes into the patches that add those
      lines. Otherwise I ran into some ugly dependencies.
      
      Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org
      Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      8f43d03f
    • Ingo Molnar's avatar
      [PATCH] sched: voluntary kernel preemption · f8cbd99b
      Ingo Molnar authored
      
      
      This patch adds a new preemption model: 'Voluntary Kernel Preemption'.  The
      3 models can be selected from a new menu:
      
                  (X) No Forced Preemption (Server)
                  ( ) Voluntary Kernel Preemption (Desktop)
                  ( ) Preemptible Kernel (Low-Latency Desktop)
      
      we still default to the stock (Server) preemption model.
      
      Voluntary preemption works by adding a cond_resched()
      (reschedule-if-needed) call to every might_sleep() check.  It is lighter
      than CONFIG_PREEMPT - at the cost of not having as tight latencies.  It
      represents a different latency/complexity/overhead tradeoff.
      
      It has no runtime impact at all if disabled.  Here are size stats that show
      how the various preemption models impact the kernel's size:
      
          text    data     bss     dec     hex filename
       3618774  547184  179896 4345854  424ffe vmlinux.stock
       3626406  547184  179896 4353486  426dce vmlinux.voluntary   +0.2%
       3748414  548640  179896 4476950  445016 vmlinux.preempt     +3.5%
      
      voluntary-preempt is +0.2% of .text, preempt is +3.5%.
      
      This feature has been tested for many months by lots of people (and it's
      also included in the RHEL4 distribution and earlier variants were in Fedora
      as well), and it's intended for users and distributions who dont want to
      use full-blown CONFIG_PREEMPT for one reason or another.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      f8cbd99b
    • Ingo Molnar's avatar
      [PATCH] enable PREEMPT_BKL on !PREEMPT+SMP too · f704f56a
      Ingo Molnar authored
      
      
      The only sane way to clean up the current 3 lock_kernel() variants seems to
      be to remove the spinlock-based BKL implementations altogether, and to keep
      the semaphore-based one only.  If we dont want to do that for whatever
      reason then i'm afraid we have to live with the current complexity.  (but
      i'm open for other cleanup suggestions as well.)
      
      To explore this possibility we'll (at a minimum) have to know whether the
      semaphore-based BKL works fine on plain SMP too.  The patch below enables
      this.
      
      The patch may make sense in isolation as well, as it might bring
      performance benefits: code that would formerly spin on the BKL spinlock
      will now schedule away and give up the CPU.  It might introduce performance
      regressions as well, if any performance-critical code uses the BKL heavily
      and gets overscheduled due to the semaphore.  I very much hope there is no
      such performance-critical codepath left though.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      f704f56a
    • Ingo Molnar's avatar
      [PATCH] consolidate PREEMPT options into kernel/Kconfig.preempt · cc19ca86
      Ingo Molnar authored
      
      
      This patch consolidates the CONFIG_PREEMPT and CONFIG_PREEMPT_BKL
      preemption options into kernel/Kconfig.preempt.  This, besides reducing
      source-code, also enables more centralized tweaking of preemption related
      options.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      cc19ca86
    • Dinakar Guniguntala's avatar
      [PATCH] Dynamic sched domains: ia64 changes · 7f1867a5
      Dinakar Guniguntala authored
      
      
      ia64 changes similar to kernel/sched.c.
      Signed-off-by: default avatarDinakar Guniguntala <dino@in.ibm.com>
      Acked-by: default avatarPaul Jackson <pj@sgi.com>
      Acked-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      7f1867a5
    • Dinakar Guniguntala's avatar
      [PATCH] Dynamic sched domains: cpuset changes · 85d7b949
      Dinakar Guniguntala authored
      
      
      Adds the core update_cpu_domains code and updated cpusets documentation
      Signed-off-by: default avatarDinakar Guniguntala <dino@in.ibm.com>
      Acked-by: default avatarPaul Jackson <pj@sgi.com>
      Acked-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      85d7b949
    • Dinakar Guniguntala's avatar
      [PATCH] Dynamic sched domains: sched changes · 1a20ff27
      Dinakar Guniguntala authored
      
      
      The following patches add dynamic sched domains functionality that was
      extensively discussed on lkml and lse-tech.  I would like to see this added to
      -mm
      
      o The main advantage with this feature is that it ensures that the scheduler
        load balacing code only balances against the cpus that are in the sched
        domain as defined by an exclusive cpuset and not all of the cpus in the
        system. This removes any overhead due to load balancing code trying to
        pull tasks outside of the cpu exclusive cpuset only to be prevented by
        the tasks' cpus_allowed mask.
      o cpu exclusive cpusets are useful for servers running orthogonal
        workloads such as RT applications requiring low latency and HPC
        applications that are throughput sensitive
      
      o It provides a new API partition_sched_domains in sched.c
        that makes dynamic sched domains possible.
      o cpu_exclusive cpusets sets are now associated with a sched domain.
        Which means that the users can dynamically modify the sched domains
        through the cpuset file system interface
      o ia64 sched domain code has been updated to support this feature as well
      o Currently, this does not support hotplug. (However some of my tests
        indicate hotplug+preempt is currently broken)
      o I have tested it extensively on x86.
      o This should have very minimal impact on performance as none of
        the fast paths are affected
      Signed-off-by: default avatarDinakar Guniguntala <dino@in.ibm.com>
      Acked-by: default avatarPaul Jackson <pj@sgi.com>
      Acked-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Acked-by: default avatarMatthew Dobson <colpatch@us.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      1a20ff27
    • Olivier Croquette's avatar
      [PATCH] Changing RT priority without CAP_SYS_NICE · 37e4ab3f
      Olivier Croquette authored
      
      
      Presently, a process without the capability CAP_SYS_NICE can not change
      its own policy, which is OK.
      
      But it can also not decrease its RT priority (if scheduled with policy
      SCHED_RR or SCHED_FIFO), which is what this patch changes.
      
      The rationale is the same as for the nice value: a process should be
      able to require less priority for itself. Increasing the priority is
      still not allowed.
      
      This is for example useful if you give a multithreaded user process a RT
      priority, and the process would like to organize its internal threads
      using priorities also. Then you can give the process the highest
      priority needed N, and the process starts its threads with lower
      priorities: N-1, N-2...
      
      The POSIX norm says that the permissions are implementation specific, so
      I think we can do that.
      
      In a sense, it makes the permissions consistent whatever the policy is:
      with this patch, process scheduled by SCHED_FIFO, SCHED_RR and
      SCHED_OTHER can all decrease their priority.
      
      From: Ingo Molnar <mingo@elte.hu>
      
      cleaned up and merged to -mm.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      37e4ab3f
    • Chen Shang's avatar
      [PATCH] sched: micro-optimize task requeueing in schedule() · a3464a10
      Chen Shang authored
      
      
      micro-optimize task requeueing in schedule() & clean up recalc_task_prio().
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      a3464a10
    • Nick Piggin's avatar
      [PATCH] sched: relax pinned balancing · 77391d71
      Nick Piggin authored
      
      
      The maximum rebalance interval allowed by the multiprocessor balancing
      backoff is often not large enough to handle corner cases where there are
      lots of tasks pinned on a CPU.  Suresh reported:
      
      	I see system livelock's if for example I have 7000 processes
      	pinned onto one cpu (this is on the fastest 8-way system I
      	have access to).
      
      After this patch, the machine is reported to go well above this number.
      Signed-off-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Acked-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      77391d71
    • Nick Piggin's avatar
      [PATCH] sched: consolidate sbe sbf · 476d139c
      Nick Piggin authored
      
      
      Consolidate balance-on-exec with balance-on-fork.  This is made easy by the
      sched-domains RCU patches.
      
      As well as the general goodness of code reduction, this allows the runqueues
      to be unlocked during balance-on-fork.
      
      schedstats is a problem.  Maybe just have balance-on-event instead of
      distinguishing fork and exec?
      Signed-off-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Acked-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      476d139c
    • Nick Piggin's avatar
      [PATCH] sched: RCU domains · 674311d5
      Nick Piggin authored
      
      
      One of the problems with the multilevel balance-on-fork/exec is that it needs
      to jump through hoops to satisfy sched-domain's locking semantics (that is,
      you may traverse your own domain when not preemptable, and you may traverse
      others' domains when holding their runqueue lock).
      
      balance-on-exec had to potentially migrate between more than one CPU before
      finding a final CPU to migrate to, and balance-on-fork needed to potentially
      take multiple runqueue locks.
      
      So bite the bullet and make sched-domains go completely RCU.  This actually
      simplifies the code quite a bit.
      
      From: Ingo Molnar <mingo@elte.hu>
      
      schedstats RCU fix, and a nice comment on for_each_domain, from Ingo.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Acked-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      674311d5
    • Nick Piggin's avatar
      [PATCH] sched: multilevel sbe sbf · 3dbd5342
      Nick Piggin authored
      
      
      The fundamental problem that Suresh has with balance on exec and fork is that
      it only tries to balance the top level domain with the flag set.
      
      This was worked around by removing degenerate domains, but is still a problem
      if people want to start using more complex sched-domains, especially
      multilevel NUMA that ia64 is already using.
      
      This patch makes balance on fork and exec try balancing over not just the top
      most domain with the flag set, but all the way down the domain tree.
      Signed-off-by: default avatarNick Piggin <nickpiggin@yahoo.com.au>
      Acked-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      3dbd5342