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    Subject[PATCH] clk: ti: Fix reference imbalance in ti_find_clock_provider
    From: Jan Kiszka <jan.kiszka@siemens.com>

    When a clock is found via clock-output-names, we need to reference it
    explicitly to match of_find_node_by_name behavior. Failing to do so
    causes warnings like this:

    ------------[ cut here ]------------
    WARNING: CPU: 0 PID: 0 at lib/refcount.c:25 kobject_get+0x9c/0xa0
    refcount_t: addition on 0; use-after-free.
    Modules linked in:
    CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0+ #37
    Hardware name: Generic AM33XX (Flattened Device Tree)
    unwind_backtrace from show_stack+0x10/0x14
    show_stack from dump_stack_lvl+0x40/0x4c
    dump_stack_lvl from __warn+0xc8/0x13c
    __warn from warn_slowpath_fmt+0x78/0xa8
    warn_slowpath_fmt from kobject_get+0x9c/0xa0
    kobject_get from of_node_get+0x14/0x1c
    of_node_get from of_fwnode_get+0x34/0x40
    of_fwnode_get from fwnode_full_name_string+0x34/0xa0
    fwnode_full_name_string from device_node_string+0x604/0x6d0
    device_node_string from pointer+0x38c/0x5b0
    pointer from vsnprintf+0x230/0x3cc
    vsnprintf from vprintk_store+0x10c/0x3fc
    vprintk_store from vprintk_emit+0x70/0x240
    vprintk_emit from vprintk_default+0x20/0x28
    vprintk_default from _printk+0x2c/0x5c
    _printk from of_node_release+0x11c/0x124
    of_node_release from kobject_put+0x98/0x104
    kobject_put from ti_dt_clocks_register+0x2d8/0x3a8
    ti_dt_clocks_register from am33xx_dt_clk_init+0x14/0xa4
    am33xx_dt_clk_init from omap_init_time_of+0x8/0x10
    omap_init_time_of from start_kernel+0x4f8/0x6b0
    start_kernel from 0x0
    ---[ end trace 0000000000000000 ]---

    Fixes: 51f661ef9a10 ("clk: ti: Add ti_find_clock_provider() to use clock-output-names")
    Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
    ---

    Tested against 5.19 as at least current Linus master does not boot on
    the BeagleBone Black.

    drivers/clk/ti/clk.c | 4 +++-
    1 file changed, 3 insertions(+), 1 deletion(-)

    diff --git a/drivers/clk/ti/clk.c b/drivers/clk/ti/clk.c
    index ef2a445c63a3..5261642974df 100644
    --- a/drivers/clk/ti/clk.c
    +++ b/drivers/clk/ti/clk.c
    @@ -142,8 +142,10 @@ static struct device_node *ti_find_clock_provider(struct device_node *from,
    of_node_put(from);
    kfree(tmp);

    - if (found)
    + if (found) {
    + of_node_get(np);
    return np;
    + }

    /* Fall back to using old node name base provider name */
    return of_find_node_by_name(from, name);
    --
    2.35.3
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