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* [PATCH] Revert "tty: serial: 8250: add CON_CONSDEV to flags"
@ 2016-12-11  2:05 Herbert Xu
  2016-12-11  7:12 ` Greg Kroah-Hartman
  0 siblings, 1 reply; 7+ messages in thread
From: Herbert Xu @ 2016-12-11  2:05 UTC (permalink / raw)
  To: Greg Kroah-Hartman, linux-serial, Linux Kernel Mailing List,
	Matthew Leach

This commit needs to be reverted because it prevents people from
using the serial console as a secondary console with input being
directed to tty0.

IOW, if you boot with console=ttyS0 console=tty0 then all kernels
prior to this commit will produce output on both ttyS0 and tty0
but input will only be taken from tty0.  With this patch the serial
console will always be the primary console instead of tty0,
potentially preventing people from getting into their machines in
emergency situations.

Fixes: d03516df8375 ("tty: serial: 8250: add CON_CONSDEV to flags")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 240a361..e8819aa 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -675,7 +675,7 @@ static int univ8250_console_match(struct console *co, char *name, int idx,
 	.device		= uart_console_device,
 	.setup		= univ8250_console_setup,
 	.match		= univ8250_console_match,
-	.flags		= CON_PRINTBUFFER | CON_ANYTIME | CON_CONSDEV,
+	.flags		= CON_PRINTBUFFER | CON_ANYTIME,
 	.index		= -1,
 	.data		= &serial8250_reg,
 };
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply related	[flat|nested] 7+ messages in thread
* [PATCH] Revert "tty: serial: 8250: add CON_CONSDEV to flags"
@ 2016-11-14  2:53 Huacai Chen
  2016-11-14 11:49 ` Greg Kroah-Hartman
  0 siblings, 1 reply; 7+ messages in thread
From: Huacai Chen @ 2016-11-14  2:53 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: linux-serial, Matthew Leach, Huacai Chen, stable, Ce Sun

This reverts commit d03516df837587368fc6e75591f6329c072b9eb5. From
Documentation/serial-console.txt we can know that serial port becomes
the system console only when it appears in the kernel parameters as the
last console device. But commit d03516df837587 adds a CON_CONSDEV flag
to univ8250_console and breaks this convention. After that either we
use "console=tty console=ttyS0" or "console=ttyS0 console=tty", serial
port will always be the system console.

Cc: stable@vger.kernel.org
Signed-off-by: Ce Sun <sunc@lemote.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 drivers/tty/serial/8250/8250_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 240a361..e8819aa 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -675,7 +675,7 @@ static struct console univ8250_console = {
 	.device		= uart_console_device,
 	.setup		= univ8250_console_setup,
 	.match		= univ8250_console_match,
-	.flags		= CON_PRINTBUFFER | CON_ANYTIME | CON_CONSDEV,
+	.flags		= CON_PRINTBUFFER | CON_ANYTIME,
 	.index		= -1,
 	.data		= &serial8250_reg,
 };
-- 
2.7.0

^ permalink raw reply related	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2017-01-17  8:01 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-12-11  2:05 [PATCH] Revert "tty: serial: 8250: add CON_CONSDEV to flags" Herbert Xu
2016-12-11  7:12 ` Greg Kroah-Hartman
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2016-11-14  2:53 Huacai Chen
2016-11-14 11:49 ` Greg Kroah-Hartman
2017-01-17  7:34   ` 陈华才
2017-01-17  7:54     ` Greg Kroah-Hartman
2017-01-17  8:01       ` 陈华才

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