3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jason Liu <[email protected]> commit 7964c06d66c76507d8b6b662bffea770c29ef0ce upstream. when run the folloing command under shell, it will return error sh/$ echo 1 > /proc/sys/vm/compact_memory sh/$ sh: write error: Bad address After strace, I found the following log: ... write(1, "1\n", 2) = 3 write(1, "", 4294967295) = -1 EFAULT (Bad address) write(2, "echo: write error: Bad address\n", 31echo: write error: Bad address ) = 31 This tells system return 3(COMPACT_COMPLETE) after write data to compact_memory. The fix is to make the system just return 0 instead 3(COMPACT_COMPLETE) from sysctl_compaction_handler after compaction_nodes finished. Signed-off-by: Jason Liu <[email protected]> Suggested-by: David Rientjes <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Minchan Kim <[email protected]> Cc: KAMEZAWA Hiroyuki <[email protected]> Acked-by: David Rientjes <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- mm/compaction.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index 6b807e4..f8f5c11 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1210,7 +1210,7 @@ static int compact_node(int nid) } /* Compact all nodes in the system */ -static int compact_nodes(void) +static void compact_nodes(void) { int nid; @@ -1219,8 +1219,6 @@ static int compact_nodes(void) for_each_online_node(nid) compact_node(nid); - - return COMPACT_COMPLETE; } /* The written value is actually unused, all memory is compacted */ @@ -1231,7 +1229,7 @@ int sysctl_compaction_handler(struct ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos) { if (write) - return compact_nodes(); + compact_nodes(); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
