4.9-stable review patch. If anyone has any objections, please let me know.
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From: Geert Uytterhoeven geert+renesas@glider.be
commit 666902e42fd8344b923c02dc5b0f37948ff4f225 upstream.
"%pCr" formats the current rate of a clock, and calls clk_get_rate(). The latter obtains a mutex, hence it must not be called from atomic context.
Remove support for this rarely-used format, as vsprintf() (and e.g. printk()) must be callable from any context.
Any remaining out-of-tree users will start seeing the clock's name printed instead of its rate.
Reported-by: Jia-Ju Bai baijiaju1990@gmail.com Fixes: 900cca2944254edd ("lib/vsprintf: add %pC{,n,r} format specifiers for clocks") Link: http://lkml.kernel.org/r/1527845302-12159-5-git-send-email-geert+renesas@gli... To: Jia-Ju Bai baijiaju1990@gmail.com To: Jonathan Corbet corbet@lwn.net To: Michael Turquette mturquette@baylibre.com To: Stephen Boyd sboyd@kernel.org To: Zhang Rui rui.zhang@intel.com To: Eduardo Valentin edubezval@gmail.com To: Eric Anholt eric@anholt.net To: Stefan Wahren stefan.wahren@i2se.com To: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Sergey Senozhatsky sergey.senozhatsky.work@gmail.com Cc: Petr Mladek pmladek@suse.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Steven Rostedt rostedt@goodmis.org Cc: linux-doc@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: linux-serial@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-renesas-soc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Geert Uytterhoeven geert+renesas@glider.be Cc: stable@vger.kernel.org # 4.1+ Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be Signed-off-by: Petr Mladek pmladek@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- Documentation/printk-formats.txt | 3 +-- lib/vsprintf.c | 3 --- 2 files changed, 1 insertion(+), 5 deletions(-)
--- a/Documentation/printk-formats.txt +++ b/Documentation/printk-formats.txt @@ -279,11 +279,10 @@ struct clk:
%pC pll1 %pCn pll1 - %pCr 1560000000
For printing struct clk structures. '%pC' and '%pCn' print the name (Common Clock Framework) or address (legacy clock framework) of the - structure; '%pCr' prints the current clock rate. + structure.
Passed by reference.
--- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1391,9 +1391,6 @@ char *clock(char *buf, char *end, struct return string(buf, end, NULL, spec);
switch (fmt[1]) { - case 'r': - return number(buf, end, clk_get_rate(clk), spec); - case 'n': default: #ifdef CONFIG_COMMON_CLK