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-rw-r--r--kernel/trace/ftrace.c30
1 files changed, 22 insertions, 8 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 483b8c1b1de0..31c90fec4158 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1925,8 +1925,16 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
1925 * when we are adding another op to the rec or removing the 1925 * when we are adding another op to the rec or removing the
1926 * current one. Thus, if the op is being added, we can 1926 * current one. Thus, if the op is being added, we can
1927 * ignore it because it hasn't attached itself to the rec 1927 * ignore it because it hasn't attached itself to the rec
1928 * yet. That means we just need to find the op that has a 1928 * yet.
1929 * trampoline and is not beeing added. 1929 *
1930 * If an ops is being modified (hooking to different functions)
1931 * then we don't care about the new functions that are being
1932 * added, just the old ones (that are probably being removed).
1933 *
1934 * If we are adding an ops to a function that already is using
1935 * a trampoline, it needs to be removed (trampolines are only
1936 * for single ops connected), then an ops that is not being
1937 * modified also needs to be checked.
1930 */ 1938 */
1931 do_for_each_ftrace_op(op, ftrace_ops_list) { 1939 do_for_each_ftrace_op(op, ftrace_ops_list) {
1932 1940
@@ -1940,17 +1948,23 @@ ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
1940 if (op->flags & FTRACE_OPS_FL_ADDING) 1948 if (op->flags & FTRACE_OPS_FL_ADDING)
1941 continue; 1949 continue;
1942 1950
1951
1943 /* 1952 /*
1944 * If the ops is not being added and has a trampoline, 1953 * If the ops is being modified and is in the old
1945 * then it must be the one that we want! 1954 * hash, then it is probably being removed from this
1955 * function.
1946 */ 1956 */
1947 if (hash_contains_ip(ip, op->func_hash))
1948 return op;
1949
1950 /* If the ops is being modified, it may be in the old hash. */
1951 if ((op->flags & FTRACE_OPS_FL_MODIFYING) && 1957 if ((op->flags & FTRACE_OPS_FL_MODIFYING) &&
1952 hash_contains_ip(ip, &op->old_hash)) 1958 hash_contains_ip(ip, &op->old_hash))
1953 return op; 1959 return op;
1960 /*
1961 * If the ops is not being added or modified, and it's
1962 * in its normal filter hash, then this must be the one
1963 * we want!
1964 */
1965 if (!(op->flags & FTRACE_OPS_FL_MODIFYING) &&
1966 hash_contains_ip(ip, op->func_hash))
1967 return op;
1954 1968
1955 } while_for_each_ftrace_op(op); 1969 } while_for_each_ftrace_op(op);
1956 1970