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author | Fugang Duan <fugang.duan@nxp.com> | 2020-11-11 05:51:36 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-11-12 11:39:53 +0300 |
commit | e67c139c488e84e7eae6c333231e791f0e89b3fb (patch) | |
tree | fbaf0eef288eefcc641d39c8416aabb730673026 /Documentation/Changes | |
parent | d4122754442799187d5d537a9c039a49a67e57f1 (diff) | |
download | linux-e67c139c488e84e7eae6c333231e791f0e89b3fb.tar.xz |
tty: serial: imx: keep console clocks always on
For below code, there has chance to cause deadlock in SMP system:
Thread 1:
clk_enable_lock();
pr_info("debug message");
clk_enable_unlock();
Thread 2:
imx_uart_console_write()
clk_enable()
clk_enable_lock();
Thread 1:
Acuired clk enable_lock -> printk -> console_trylock_spinning
Thread 2:
console_unlock() -> imx_uart_console_write -> clk_disable -> Acquite clk enable_lock
So the patch is to keep console port clocks always on like
other console drivers.
Fixes: 1cf93e0d5488 ("serial: imx: remove the uart_console() check")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20201111025136.29818-1-fugang.duan@nxp.com
Cc: stable <stable@vger.kernel.org>
[fix up build warning - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/Changes')
0 files changed, 0 insertions, 0 deletions