Commit b4fc4e83 authored Oct 05, 2018 by Rasmus Villemoes Committed by Greg Kroah-Hartman Oct 11, 2018

staging: greybus: loopback.c: remove unused gb_loopback::lbid



It's not obvious how the code prevents adding more than 31 elements to
the list and thus invoking undefined behaviour in the 1 << new_lbid
expression, and in practice causing ->lbid values to repeat every 32
elements.

But the definition of struct gb_loopback is local to loopback.c, and the
lbid field is entirely unused outside of this function, so it seems we
can just drop it entirely.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent aa5a54a0

drivers/staging/greybus/loopback.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -97,7 +97,6 @@ struct gb_loopback {
		u32 timeout_min;
		u32 timeout_max;
		u32 outstanding_operations_max;
		u32 lbid;
		u64 elapsed_nsecs;
		u32 apbridge_latency_ts;
		u32 gbphy_latency_ts;
		@@ -1014,16 +1013,9 @@ static int gb_loopback_bus_id_compare(void priv, struct list_head lha,

		static void gb_loopback_insert_id(struct gb_loopback *gb)
		{
		struct gb_loopback *gb_list;
		u32 new_lbid = 0;

		/* perform an insertion sort */
		list_add_tail(&gb->entry, &gb_dev.list);
		list_sort(NULL, &gb_dev.list, gb_loopback_bus_id_compare);
		list_for_each_entry(gb_list, &gb_dev.list, entry) {
		gb_list->lbid = 1 << new_lbid;
		new_lbid++;
		}
		}

		#define DEBUGFS_NAMELEN 32

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