6.6-stable review patch. If anyone has any objections, please let me know.
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From: Stephen Boyd sboyd@kernel.org
[ Upstream commit 9d1e795f754db1ac3344528b7af0b17b8146f321 ]
Similar to the previous commit, we should make sure that all devices are runtime resumed before printing the clk_summary through debugfs. Failure to do so would result in a deadlock if the thread is resuming a device to print clk state and that device is also runtime resuming in another thread, e.g the screen is turning on and the display driver is starting up. We remove the calls to clk_pm_runtime_{get,put}() in this path because they're superfluous now that we know the devices are runtime resumed. This also squashes a bug where the return value of clk_pm_runtime_get() wasn't checked, leading to an RPM count underflow on error paths.
Fixes: 1bb294a7981c ("clk: Enable/Disable runtime PM for clk_summary") Cc: Taniya Das quic_tdas@quicinc.com Cc: Douglas Anderson dianders@chromium.org Signed-off-by: Stephen Boyd sboyd@kernel.org Link: https://lore.kernel.org/r/20240325184204.745706-6-sboyd@kernel.org Reviewed-by: Douglas Anderson dianders@chromium.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/clk.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 011e7632541fa..4a67c0d4823cf 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3321,9 +3321,7 @@ static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c, { struct clk_core *child;
- clk_pm_runtime_get(c); clk_summary_show_one(s, c, level); - clk_pm_runtime_put(c);
hlist_for_each_entry(child, &c->children, child_node) clk_summary_show_subtree(s, child, level + 1); @@ -3333,11 +3331,15 @@ static int clk_summary_show(struct seq_file *s, void *data) { struct clk_core *c; struct hlist_head **lists = s->private; + int ret;
seq_puts(s, " enable prepare protect duty hardware connection\n"); seq_puts(s, " clock count count count rate accuracy phase cycle enable consumer id\n"); seq_puts(s, "---------------------------------------------------------------------------------------------------------------------------------------------\n");
+ ret = clk_pm_runtime_get_all(); + if (ret) + return ret;
clk_prepare_lock();
@@ -3346,6 +3348,7 @@ static int clk_summary_show(struct seq_file *s, void *data) clk_summary_show_subtree(s, c, 0);
clk_prepare_unlock(); + clk_pm_runtime_put_all();
return 0; } @@ -3393,8 +3396,14 @@ static int clk_dump_show(struct seq_file *s, void *data) struct clk_core *c; bool first_node = true; struct hlist_head **lists = s->private; + int ret; + + ret = clk_pm_runtime_get_all(); + if (ret) + return ret;
seq_putc(s, '{'); + clk_prepare_lock();
for (; *lists; lists++) { @@ -3407,6 +3416,7 @@ static int clk_dump_show(struct seq_file *s, void *data) }
clk_prepare_unlock(); + clk_pm_runtime_put_all();
seq_puts(s, "}\n"); return 0;