On 4/25/19 6:35 AM, Anup Patel wrote:
The Linux kernel will auto-disables all boot consoles whenever it
gets a preferred real console.
Currently on RISC-V systems, if we have a real console which is not
RISCV SBI console then boot consoles (such as earlycon=sbi) are not
auto-disabled when a real console (ttyS0 or ttySIF0) is available.
This results in duplicate prints at boot-time after kernel starts
using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel
parameter was passed by bootloader.
The reason for above issue is that RISCV SBI console always adds
itself as preferred console which is causing other real consoles
to be not used as preferred console.
Do we even need HVC_SBI console to be enabled by default? Disabling
CONFIG_HVC_RISCV_SBI seems to be fine while running in QEMU.
If we don't need it, I suggest we should remove the config option from
defconfig in addition to this patch.
Regards,
Atish
Ideally "console=" kernel parameter passed by bootloaders should
be the one selecting a preferred real console.
This patch fixes above issue by not forcing RISCV SBI console as
preferred console.
Fixes: afa6b1ccfad5 ("tty: New RISC-V SBI console driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
---
drivers/tty/hvc/hvc_riscv_sbi.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
index 75155bde2b88..31f53fa77e4a 100644
--- a/drivers/tty/hvc/hvc_riscv_sbi.c
+++ b/drivers/tty/hvc/hvc_riscv_sbi.c
@@ -53,7 +53,6 @@ device_initcall(hvc_sbi_init);
static int __init hvc_sbi_console_init(void)
{
hvc_instantiate(0, 0, &hvc_sbi_ops);
- add_preferred_console("hvc", 0, NULL);
return 0;
}