gve: fix the wrong AdminQ buffer queue index check

Browse source

The 'tail' and 'head' are 'unsigned int' type free-running count, when
'head' is overflow, the 'int i (= tail) < u32 head' will be false:

Only '- loop 0: idx = 63' result is shown, so it needs to use 'int' type
to compare, it can handle the overflow correctly.

typedef uint32_t u32;

int main()
{
        u32 tail, head;
        int stail, shead;
        int i, loop;

        tail = 0xffffffff;
        head = 0x00000000;

        for (i = tail, loop = 0; i < head; i++) {
                unsigned int idx = i & 63;

                printf("+ loop %d: idx = %u\n", loop++, idx);
        }

        stail = tail;
        shead = head;
        for (i = stail, loop = 0; i < shead; i++) {
                unsigned int idx = i & 63;

                printf("- loop %d: idx = %u\n", loop++, idx);
        }

        return 0;
}

Fixes: 5cdad90de6 ("gve: Batch AQ commands for creating and destroying queues.")
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

...

This commit is contained in:

Haiyue Wang 2022-01-28 18:47:14 +08:00 • committed by David S. Miller

parent 501c8f5e39

commit 1f84a9450d

1 changed files with 1 additions and 1 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

drivers/net/ethernet/google/gve/gve_adminq.c

View file