| Message ID | 20120228205621.GC3252@dhcp-172-17-108-109.mtv.corp.google.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On Wed, Feb 29, 2012 at 05:56:21AM +0900, Tejun Heo wrote: > memblock allocator aligns @size to @align to reduce the amount of > fragmentation. 7bd0b0f0da "memblock: Reimplement memblock allocation > using reverse free area iterator" broke it by incorrectly relocating > @size aligning to memblock_find_in_range_node(). As the aligned size > is not propagated back to memblock_alloc_base_nid(), the actually > reserved size isn't aligned. > > While this increases memory use for memblock reserved array, this > shouldn't cause any critical failure; however, it seems that the size > aligning was hiding a use-beyond-allocation bug in sparc64 and losing > the aligning causes boot failure. > > The underlying problem is currently being debugged but this is a > proper fix in itself, it's already pretty late in -rc cycle for boot > failures and reverting the change for debugging isn't difficult. > Restore the size aligning moving it to memblock_alloc_base_nid(). > > Signed-off-by: Tejun Heo <tj@kernel.org> > Reported-by: Meelis Roos <mroos@linux.ee> > Reported-by: Sam Ravnborg <sam@ravnborg.org> Actually not :-( I only fooled around with some clueless suggestions - I do not have any sparc64 boxes. And my sparc32 box that is alive atm, does not exhibit this problem. Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/mm/memblock.c b/mm/memblock.c index 77b5f22..99f2855 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -99,9 +99,6 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start, phys_addr_t this_start, this_end, cand; u64 i; - /* align @size to avoid excessive fragmentation on reserved array */ - size = round_up(size, align); - /* pump up @end */ if (end == MEMBLOCK_ALLOC_ACCESSIBLE) end = memblock.current_limit; @@ -731,6 +728,9 @@ static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size, { phys_addr_t found; + /* align @size to avoid excessive fragmentation on reserved array */ + size = round_up(size, align); + found = memblock_find_in_range_node(0, max_addr, size, align, nid); if (found && !memblock_reserve(found, size)) return found;
memblock allocator aligns @size to @align to reduce the amount of fragmentation. 7bd0b0f0da "memblock: Reimplement memblock allocation using reverse free area iterator" broke it by incorrectly relocating @size aligning to memblock_find_in_range_node(). As the aligned size is not propagated back to memblock_alloc_base_nid(), the actually reserved size isn't aligned. While this increases memory use for memblock reserved array, this shouldn't cause any critical failure; however, it seems that the size aligning was hiding a use-beyond-allocation bug in sparc64 and losing the aligning causes boot failure. The underlying problem is currently being debugged but this is a proper fix in itself, it's already pretty late in -rc cycle for boot failures and reverting the change for debugging isn't difficult. Restore the size aligning moving it to memblock_alloc_base_nid(). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Meelis Roos <mroos@linux.ee> Reported-by: Sam Ravnborg <sam@ravnborg.org> LKML-Reference: <alpine.SOC.1.00.1202130942030.1488@math.ut.ee> --- mm/memblock.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html