Re: [PATCH v3 -next 11/11] serial: 8250_early: Remove setup_early_serial8250_console()

From: Peter Hurley
Date: Thu Apr 02 2015 - 12:31:52 EST


Hi Yinghai,

On 04/02/2015 05:15 AM, Yinghai Lu wrote:
> On Wed, Apr 1, 2015 at 8:22 PM, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> wrote:
>> The documented behavior of console=ttyS options, to which your
>> quote refers, clearly states:
>>
>> Default is "9600n8".
>
> drivers/tty/serial/8250/8250_early.c:early_serial8250_setup
> still have calling to probe_baud, but it is not triggered.
>
> Here is root cause.
> The gap between entries in earlycon_table cause
> iteration fail to find next entry, so uart8250 handler is
> not called proplerly.

Thanks for finding that bug; so the earlycon never started, right?

> attached patch fix the problem.

Would you please try the patch below instead?

Regards,
Peter Hurley

--- >% ---
From: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
Subject: [PATCH] earlycon: Fix __earlycon_table stride

Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
---
include/asm-generic/vmlinux.lds.h | 2 +-
include/linux/serial_core.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 7b0ef49..2e11f31 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -151,7 +151,7 @@
#endif

#ifdef CONFIG_SERIAL_EARLYCON
-#define EARLYCON_TABLE() . = ALIGN(8); \
+#define EARLYCON_TABLE() STRUCT_ALIGN(); \
VMLINUX_SYMBOL(__earlycon_table) = .; \
*(__earlycon_table) \
*(__earlycon_table_end)
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 34de168..025dad9 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -342,7 +342,7 @@ struct earlycon_device {
struct earlycon_id {
char name[16];
int (*setup)(struct earlycon_device *, const char *options);
-};
+} __aligned(32);

extern int setup_earlycon(char *buf);
extern int of_setup_earlycon(unsigned long addr,
--
2.3.5

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