24 Mar, 2011

1 commit

  • …p_elfcorehdr and saved_max_pfn

    The Xen PV drivers in a crashed HVM guest can not connect to the dom0
    backend drivers because both frontend and backend drivers are still in
    connected state. To run the connection reset function only in case of a
    crashdump, the is_kdump_kernel() function needs to be available for the PV
    driver modules.

    Consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn into
    kernel/crash_dump.c Also export elfcorehdr_addr to make is_kdump_kernel()
    usable for modules.

    Leave 'elfcorehdr' as early_param(). This changes powerpc from __setup()
    to early_param(). It adds an address range check from x86 also on ia64
    and powerpc.

    [akpm@linux-foundation.org: additional #includes]
    [akpm@linux-foundation.org: remove elfcorehdr_addr export]
    [akpm@linux-foundation.org: fix for Tejun's mm/nobootmem.c changes]
    Signed-off-by: Olaf Hering <olaf@aepfle.de>
    Cc: Russell King <rmk@arm.linux.org.uk>
    Cc: "Luck, Tony" <tony.luck@intel.com>
    Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Cc: Paul Mundt <lethal@linux-sh.org>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: "H. Peter Anvin" <hpa@zytor.com>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

    Olaf Hering
     

27 Oct, 2010

1 commit

  • Keep the current interface but ignore the KM_type and use a stack based
    approach.

    The advantage is that we get rid of crappy code like:

    #define __KM_PTE \
    (in_nmi() ? KM_NMI_PTE : \
    in_irq() ? KM_IRQ_PTE : \
    KM_PTE0)

    and in general can stop worrying about what context we're in and what kmap
    slots might be appropriate for that.

    The downside is that FRV kmap_atomic() gets more expensive.

    For now we use a CPP trick suggested by Andrew:

    #define kmap_atomic(page, args...) __kmap_atomic(page)

    to avoid having to touch all kmap_atomic() users in a single patch.

    [ not compiled on:
    - mn10300: the arch doesn't actually build with highmem to begin with ]

    [akpm@linux-foundation.org: coding-style fixes]
    [akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
    Acked-by: Rik van Riel
    Signed-off-by: Peter Zijlstra
    Acked-by: Chris Metcalf
    Cc: David Howells
    Cc: Hugh Dickins
    Cc: Ingo Molnar
    Cc: Thomas Gleixner
    Cc: "H. Peter Anvin"
    Cc: Steven Rostedt
    Cc: Russell King
    Cc: Ralf Baechle
    Cc: David Miller
    Cc: Paul Mackerras
    Cc: Benjamin Herrenschmidt
    Cc: Dave Airlie
    Cc: Li Zefan
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Peter Zijlstra
     

30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

26 Oct, 2009

1 commit

  • Non-PAE 32-bit dump kernels may wrap an address around 4G and
    poke unwanted space. ptes there are 32-bit long, and since
    pfn << PAGE_SIZE may exceed this limit, high pfn bits are
    cropped and wrong address mapped by kmap_atomic_pfn in
    copy_oldmem_page.

    Don't allow this behavior in non-PAE kdump kernels by checking
    pfns passed into copy_oldmem_page. In the case of failure,
    userspace process gets EFAULT.

    [v2]
    - fix comments
    - move ifdefs inside the function

    Signed-off-by: Jiri Slaby
    Cc: Vivek Goyal
    Cc: Eric W. Biederman
    Cc: Simon Horman
    Cc: Paul Mundt
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Jiri Slaby
     

20 Oct, 2008

1 commit

  • o elfcorehdr_addr is used by not only the code under CONFIG_PROC_VMCORE
    but also by the code which is not inside CONFIG_PROC_VMCORE. For
    example, is_kdump_kernel() is used by powerpc code to determine if
    kernel is booting after a panic then use previous kernel's TCE table.
    So even if CONFIG_PROC_VMCORE is not set in second kernel, one should be
    able to correctly determine that we are booting after a panic and setup
    calgary iommu accordingly.

    o So remove the assumption that elfcorehdr_addr is under
    CONFIG_PROC_VMCORE.

    o Move definition of elfcorehdr_addr to arch dependent crash files.
    (Unfortunately crash dump does not have an arch independent file
    otherwise that would have been the best place).

    o kexec.c is not the right place as one can Have CRASH_DUMP enabled in
    second kernel without KEXEC being enabled.

    o I don't see sh setup code parsing the command line for
    elfcorehdr_addr. I am wondering how does vmcore interface work on sh.
    Anyway, I am atleast defining elfcoredhr_addr so that compilation is not
    broken on sh.

    Signed-off-by: Vivek Goyal
    Acked-by: "Eric W. Biederman"
    Acked-by: Simon Horman
    Acked-by: Paul Mundt
    Cc: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Vivek Goyal
     

20 Oct, 2007

1 commit


14 Oct, 2007

1 commit

  • Since the x86 merge, lots of files that referenced their own filenames
    are no longer correct. Rather than keep them up to date, just delete
    them, as they add no real value.

    Additionally:
    - fix up comment formatting in scx200_32.c
    - Remove a credit from myself in setup_64.c from a time when we had no SCM
    - remove longwinded history from tsc_32.c which can be figured out from
    git.

    Signed-off-by: Dave Jones
    Signed-off-by: Linus Torvalds

    Dave Jones
     

11 Oct, 2007

1 commit