From: Robin Gong <b38343@xxxxxxxxxxxxx> Sent: Wednesday, November 04, 2015 10:58 AM > To: gregkh@xxxxxxxxxxxxxxxxxxx; edubezval@xxxxxxxxx > Cc: Duan Fugang-B38611; linux-serial@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx > Subject: [PATCH v1] Revert "serial: imx: remove unbalanced clk_prepare" > > commit 9e7b399d6528 ("serial: imx: remove unbalanced clk_prepare"). > Otherwise below warning happen since there are some printk logs in > interrupt. > > [ 14.868319] udevd[501]: starting version 182 > [ 16.386107] random: nonblocking pool is initialized > [ 16.386123] ------------[ cut here ]------------ > [ 16.386140] WARNING: CPU: 0 PID: 501 at kernel/locking/mutex.c:868 > mutex_trylock+0x210/0x230() > [ 16.386146] DEBUG_LOCKS_WARN_ON(in_interrupt()) > [ 16.386149] Modules linked in: > [ 16.386157] CPU: 0 PID: 501 Comm: udevd Not tainted 4.3.0-rc1-00014- > gf843df8 #28 > [ 16.386160] Hardware name: Freescale i.MX6 SoloX (Device Tree) > [ 16.386165] Backtrace: > [ 16.386182] [<c0013e98>] (dump_backtrace) from [<c0014090>] > (show_stack+0x18/0x1c) > [ 16.386192] r6:c0af1840 r5:00000000 r4:00000000 r3:00000000 > [ 16.386201] [<c0014078>] (show_stack) from [<c02d4af8>] > (dump_stack+0x8c/0xa4) > [ 16.386216] [<c02d4a6c>] (dump_stack) from [<c002be14>] > (warn_slowpath_common+0x80/0xbc) > [ 16.386225] r6:c07b1ccc r5:00000009 r4:edcf5c60 r3:00000001 > [ 16.386234] [<c002bd94>] (warn_slowpath_common) from [<c002be88>] > (warn_slowpath_fmt+0x38/0x40) > [ 16.386246] r8:c0564694 r7:eeb76880 r6:c13323ec r5:00000001 > r4:c0976990 > [ 16.386255] [<c002be54>] (warn_slowpath_fmt) from [<c07b1ccc>] > (mutex_trylock+0x210/0x230) > [ 16.386261] r3:c0978f50 r2:c0976990 > [ 16.386264] r4:c0b29a70 > [ 16.386278] [<c07b1abc>] (mutex_trylock) from [<c0564694>] > (clk_prepare_lock+0x14/0xf4) > [ 16.386289] r8:c133000c r7:eeb76880 r6:00000037 r5:c12efbc8 > r4:eeb76880 > [ 16.386297] [<c0564680>] (clk_prepare_lock) from [<c0565e04>] > (clk_prepare+0x18/0x38) > [ 16.386303] r5:c12efbc8 r4:eeb76880 > [ 16.386311] [<c0565dec>] (clk_prepare) from [<c0379a90>] > (imx_console_write+0x34/0x248) > [ 16.386317] r4:ee999c10 r3:c134a92c > [ 16.386329] [<c0379a5c>] (imx_console_write) from [<c007ac74>] > (call_console_drivers.constprop.25+0xe0/0x104) > [ 16.386342] r10:c07b938c r9:00000000 r8:c133000c r7:00000037 > r6:edcf4000 r5:c12ef6c0 > [ 16.386345] r4:c0afef38 > [ 16.386355] [<c007ab94>] (call_console_drivers.constprop.25) from > [<c007be84>] (console_unlock+0x3fc/0x57c) > [ 16.386367] r10:c132fff0 r9:00000100 r8:00000037 r7:00000000 > r6:00000005 r5:c12f4df0 > > Signed-off-by: Robin Gong <b38343@xxxxxxxxxxxxx> > --- > drivers/tty/serial/imx.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) I remember there had patch for this. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html