From 0541881502a1276149889fe468662ff6a8fc8f6d Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 13 Jun 2013 13:17:02 -0700 Subject: [PATCH] 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 Tested-by: Joshua Covington Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1371154622-8929-3-git-send-email-yinghai@kernel.org Cc: v3.9 Signed-off-by: H. Peter Anvin --- kernel/range.c | 21 +++++++++++---------- 1 file 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 #include #include - +#include #include 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: */ -- 2.20.1