Liming Sun c79fff3feb platform/mellanox: fix potential deadlock in the tmfifo driver ... commit 638bc4ca3d upstream. This commit fixes the potential deadlock caused by the console Rx and Tx processing at the same time. Rx and Tx both take the console and tmfifo spinlock but in different order which causes potential deadlock. The fix is to use different tmfifo spinlock for Rx and Tx since they protect different resources and it's safe to split the lock. Below is the reported call trace when copying/pasting large string in the console. Rx: _raw_spin_lock_irqsave (hvc lock) __hvc_poll hvc_poll in_intr vring_interrupt mlxbf_tmfifo_rxtx_one_desc (tmfifo lock) mlxbf_tmfifo_rxtx mlxbf_tmfifo_work_rxtx Tx: _raw_spin_lock_irqsave (tmfifo lock) mlxbf_tmfifo_virtio_notify virtqueue_notify virtqueue_kick put_chars hvc_push hvc_write (hvc lock) ... do_tty_write tty_write Fixes: 1357dfd726 ("platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc") Cc: <stable@vger.kernel.org> # 5.4+ Reviewed-by: David Woods <dwoods@mellanox.com> Signed-off-by: Liming Sun <lsun@mellanox.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-01-17 19:48:42 +01:00
..
Kconfig	platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc	2019-05-06 17:54:42 +03:00
Makefile	platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc	2019-05-06 17:54:42 +03:00
mlxbf-tmfifo-regs.h	platform/mellanox: Add TmFifo driver for Mellanox BlueField Soc	2019-05-06 17:54:42 +03:00
mlxbf-tmfifo.c	platform/mellanox: fix potential deadlock in the tmfifo driver	2020-01-17 19:48:42 +01:00
mlxreg-hotplug.c	platform/mellanox: mlxreg-hotplug: Remove dev_err() usage after platform_get_irq()	2019-08-01 18:03:02 +03:00
mlxreg-io.c	platform/mellanox: Use 2-factor allocator calls	2018-07-18 13:29:11 +03:00