lkml.org 
[lkml]   [2010]   [Mar]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH] free_early_partial() should permit start == end
    On 03/26/2010 09:37 AM, Jan Beulich wrote:
    > The per-CPU allocator, when using atom_size == PAGE_SIZE, may call
    > free_area_init_partial() this way.
    >
    > Signed-off-by: Jan Beulich <jbeulich@novell.com>
    >
    > ---
    > kernel/early_res.c | 4 ++--
    > 1 file changed, 2 insertions(+), 2 deletions(-)
    >
    > --- linux-2.6.34-rc2/kernel/early_res.c 2010-03-25 15:23:45.000000000 +0100
    > +++ 2.6.34-rc2-free_early_partial-zero-size/kernel/early_res.c 2010-03-26 14:49:41.000000000 +0100
    > @@ -335,10 +335,10 @@ void __init free_early_partial(u64 start
    >
    > try_next:
    > i = find_overlapped_early(start, end);
    > - if (i >= max_early_res)
    > + r = &early_res[i];
    > + if (i >= max_early_res || !r->end)
    > return;
    >
    > - r = &early_res[i];
    > /* hole ? */
    > if (r->end >= end && r->start <= start) {
    > drop_range_partial(i, start, end);
    >
    >

    can you check if this patch work for you?

    Thanks

    Yinghai Lu

    Subject: [PATCH -v6] x86: do not free zero sized per cpu areas
    From: Ian Campbell <ian.campbell@citrix.com>

    This avoids an infinite loop in free_early_partial().

    Add a warning to free_early_partial to catch future problems.

    -v5: put back start > end back into WARN_ONCE()
    -v6: use one line for if according to linus

    Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
    Signed-off-by: Yinghai Lu <yinghai@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Ingo Molnar <mingo@elte.hu>
    ---
    kernel/early_res.c | 6 ++++++
    1 file changed, 6 insertions(+)

    Index: linux-2.6/kernel/early_res.c
    ===================================================================
    --- linux-2.6.orig/kernel/early_res.c
    +++ linux-2.6/kernel/early_res.c
    @@ -333,6 +333,12 @@ void __init free_early_partial(u64 start
    struct early_res *r;
    int i;

    + if (start == end)
    + return;
    +
    + if (WARN_ONCE(start > end, "free_early_partial: wrong range [%#llx, %#llx]\n", start, end))
    + return;
    +
    try_next:
    i = find_overlapped_early(start, end);
    if (i >= max_early_res)

    \
     
     \ /
      Last update: 2010-03-26 21:43    [W:0.027 / U:90.884 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site