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* [RFC][PATCHv2 0/4] less deadlock prone serial consoles
@ 2018-10-16  5:04 Sergey Senozhatsky
  2018-10-16  5:04 ` [RFC][PATCHv2 1/4] panic: avoid deadlocks in re-entrant console drivers Sergey Senozhatsky
                   ` (4 more replies)
  0 siblings, 5 replies; 44+ messages in thread
From: Sergey Senozhatsky @ 2018-10-16  5:04 UTC (permalink / raw)
  To: linux-kernel
  Cc: Petr Mladek, Steven Rostedt, Daniel Wang, Peter Zijlstra,
	Andrew Morton, Linus Torvalds, Greg Kroah-Hartman, Alan Cox,
	Jiri Slaby, Peter Feiner, linux-serial, Sergey Senozhatsky,
	Sergey Senozhatsky

	Hello,


	RFC


	The patch set reduces the number of ways serial consoles
can deadlock the system, including the recently reported deadlock
in panic().

The test scenario I ran on my x86_64 box:
- panic() the system while one of the CPUs holds 8250's
  uart_port->lock.

Test results:

	base		|	patched
	-----------------------------------------
	deadlock	|	flush logbuf
			|	reboot the system

To keep the cover letter short, please find full description in
commit messages.

P.S. since this is RFC I modify only 8250 serial driver.

Sergey Senozhatsky (4):
  panic: avoid deadlocks in re-entrant console drivers
  printk: move printk_safe macros to printk header
  seial: introduce uart_port locking helpers
  tty: 8250: switch to uart_port locking helpers

 drivers/tty/serial/8250/8250_core.c |  8 +--
 drivers/tty/serial/8250/8250_dma.c  |  4 +-
 drivers/tty/serial/8250/8250_port.c | 81 +++++++++++++----------------
 include/linux/printk.h              | 40 ++++++++++++++
 include/linux/serial_core.h         | 48 +++++++++++++++++
 kernel/panic.c                      |  6 +++
 kernel/printk/internal.h            | 37 -------------
 kernel/printk/printk_safe.c         |  6 ++-
 8 files changed, 141 insertions(+), 89 deletions(-)

-- 
2.19.1


^ permalink raw reply	[flat|nested] 44+ messages in thread

end of thread, other threads:[~2018-12-12 11:08 UTC | newest]

Thread overview: 44+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-16  5:04 [RFC][PATCHv2 0/4] less deadlock prone serial consoles Sergey Senozhatsky
2018-10-16  5:04 ` [RFC][PATCHv2 1/4] panic: avoid deadlocks in re-entrant console drivers Sergey Senozhatsky
2018-10-17  4:48   ` Sergey Senozhatsky
2018-10-23 11:07   ` Petr Mladek
2018-10-23 11:54     ` Sergey Senozhatsky
2018-10-23 12:04       ` Sergey Senozhatsky
2018-10-23 12:12         ` Sergey Senozhatsky
2018-10-25  9:06           ` Petr Mladek
2018-10-25  9:31             ` Sergey Senozhatsky
2018-10-25  8:29       ` Petr Mladek
2018-10-25  9:05         ` Sergey Senozhatsky
2018-10-25 10:10   ` [PATCHv3] " Sergey Senozhatsky
2018-10-25 10:51     ` kbuild test robot
2018-10-25 11:56       ` Sergey Senozhatsky
2018-10-31 12:27     ` Petr Mladek
2018-11-01  1:48       ` Sergey Senozhatsky
2018-11-01  8:08         ` Petr Mladek
2018-11-22 13:12           ` Petr Mladek
2018-12-12  0:53             ` Daniel Wang
2018-12-12  5:23               ` Sergey Senozhatsky
2018-12-12  5:59                 ` Daniel Wang
2018-12-12  6:06                   ` Sergey Senozhatsky
2018-12-12  6:09                     ` Daniel Wang
2018-10-16  5:04 ` [RFC][PATCHv2 2/4] printk: move printk_safe macros to printk header Sergey Senozhatsky
2018-10-16  7:27   ` Peter Zijlstra
2018-10-16 11:40     ` Petr Mladek
2018-10-16 12:17       ` Peter Zijlstra
2018-10-17 10:50         ` Petr Mladek
2018-10-17 14:00           ` Peter Zijlstra
2018-10-22 14:30             ` Petr Mladek
2018-10-16 12:27     ` Sergey Senozhatsky
2018-10-16 12:38       ` Peter Zijlstra
2018-10-16 12:54       ` Peter Zijlstra
2018-10-16 14:21         ` Peter Zijlstra
2018-10-17  4:32         ` Sergey Senozhatsky
2018-10-17  7:57           ` Peter Zijlstra
2018-10-17 13:36             ` Sergey Senozhatsky
2018-10-23  6:25         ` Sergey Senozhatsky
2018-10-16  5:04 ` [RFC][PATCHv2 3/4] serial: introduce uart_port locking helpers Sergey Senozhatsky
2018-12-08  3:12   ` Sergey Senozhatsky
2018-12-12 11:08     ` Greg Kroah-Hartman
2018-10-16  5:04 ` [RFC][PATCHv2 4/4] tty: 8250: switch to " Sergey Senozhatsky
2018-10-16  7:23 ` [RFC][PATCHv2 0/4] less deadlock prone serial consoles Peter Zijlstra
2018-10-16  8:12   ` Sergey Senozhatsky

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