From 89f7e9de59bf3e3cda2e00de12c66db22675a7cf Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Fri, 12 Dec 2014 15:04:16 -0800 Subject: [PATCH] clk: Really fix deadlock with mmap_sem Commit 6314b6796e3c (clk: Don't hold prepare_lock across debugfs creation, 2014-09-04) forgot to update one place where we hold the prepare_lock while creating debugfs directories. This means we still have the chance of a deadlock that the commit was trying to fix. Actually fix it by moving the debugfs creation outside the prepare_lock. Cc: # 3.18 Reported-by: Russell King Fixes: 6314b6796e3c "clk: Don't hold prepare_lock across debugfs creation" Signed-off-by: Stephen Boyd Reviewed-by: Thomas Gleixner Signed-off-by: Michael Turquette [mturquette@linaro.org: removed lockdep_assert] --- drivers/clk/clk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 44cdc47a6cc5..f4963b7d4e17 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -240,7 +240,6 @@ static const struct file_operations clk_dump_fops = { .release = single_release, }; -/* caller must hold prepare_lock */ static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry) { struct dentry *d; @@ -1944,7 +1943,6 @@ int __clk_init(struct device *dev, struct clk *clk) else clk->rate = 0; - clk_debug_register(clk); /* * walk the list of orphan clocks and reparent any that are children of * this clock @@ -1979,6 +1977,9 @@ int __clk_init(struct device *dev, struct clk *clk) out: clk_prepare_unlock(); + if (!ret) + clk_debug_register(clk); + return ret; } -- GitLab