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| author | Yinghai Lu <yinghai@kernel.org> | 2013-06-13 13:17:02 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2013-06-18 11:32:10 -0500 |
| commit | 0541881502a1276149889fe468662ff6a8fc8f6d (patch) | |
| tree | 14bdb51938b710d8b224215bccaea4cbf680b818 /kernel | |
| parent | d8d386c10630d8f7837700f4c466443d49e12cc0 (diff) | |
| download | lwn-0541881502a1276149889fe468662ff6a8fc8f6d.tar.gz lwn-0541881502a1276149889fe468662ff6a8fc8f6d.zip | |
range: Do not add new blank slot with add_range_with_merge
Joshua reported: Commit cd7b304dfaf1 (x86, range: fix missing merge
during add range) broke mtrr cleanup on his setup in 3.9.5.
corresponding commit in upstream is fbe06b7bae7c.
The reason is add_range_with_merge could generate blank spot.
We could avoid that by searching new expanded start/end, that
new range should include all connected ranges in range array.
At last add the new expanded start/end to the range array.
Also move up left array so do not add new blank slot in the
range array.
-v2: move left array to avoid enhance add_range()
-v3: include fix from Joshua about memmove declaring when
DYN_DEBUG is used.
Reported-by: Joshua Covington <joshuacov@googlemail.com>
Tested-by: Joshua Covington <joshuacov@googlemail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1371154622-8929-3-git-send-email-yinghai@kernel.org
Cc: <stable@vger.kernel.org> v3.9
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/range.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/kernel/range.c b/kernel/range.c index eb911dbce267..322ea8e93e4b 100644 --- a/kernel/range.c +++ b/kernel/range.c @@ -4,7 +4,7 @@ #include <linux/kernel.h> #include <linux/init.h> #include <linux/sort.h> - +#include <linux/string.h> #include <linux/range.h> int add_range(struct range *range, int az, int nr_range, u64 start, u64 end) @@ -32,9 +32,8 @@ int add_range_with_merge(struct range *range, int az, int nr_range, if (start >= end) return nr_range; - /* Try to merge it with old one: */ + /* get new start/end: */ for (i = 0; i < nr_range; i++) { - u64 final_start, final_end; u64 common_start, common_end; if (!range[i].end) @@ -45,14 +44,16 @@ int add_range_with_merge(struct range *range, int az, int nr_range, if (common_start > common_end) continue; - final_start = min(range[i].start, start); - final_end = max(range[i].end, end); + /* new start/end, will add it back at last */ + start = min(range[i].start, start); + end = max(range[i].end, end); - /* clear it and add it back for further merge */ - range[i].start = 0; - range[i].end = 0; - return add_range_with_merge(range, az, nr_range, - final_start, final_end); + memmove(&range[i], &range[i + 1], + (nr_range - (i + 1)) * sizeof(range[i])); + range[nr_range - 1].start = 0; + range[nr_range - 1].end = 0; + nr_range--; + i--; } /* Need to add it: */ |