ARC no console output (was Re: [PATCH 1/2] init/console: Use ttynull as a fallback when there is no console)

[Peter Korsgaard]

>>>>> "Vineet" == Vineet Gupta <vgupta at synopsys.com> writes:

 > On 1/7/21 9:04 AM, Petr Mladek wrote:
 >> On Thu 2021-01-07 08:43:16, Vineet Gupta wrote:
 >>> Hi John,
 >>> 
 >>> On 1/7/21 1:02 AM, John Ogness wrote:
 >>>> Hi Vineet,
 >>>> 
 >>>> On 2021-01-06, Vineet Gupta <vgupta at synopsys.com> wrote:
 >>>>> This breaks ARC booting (no output on console).
 >>>> 
 >>>> Could you provide the kernel boot arguments that you use? This series is
 >>>> partly about addressing users that have used boot arguments that are
 >>>> technically incorrect (even if had worked). Seeing the boot arguments of
 >>>> users that are not experiencing problems may help to reveal some of the
 >>>> unusual console usages until now.
 >>> 
 >>> 
 >>> Kernel command line: earlycon=uart8250,mmio32,0xf0005000,115200n8
 >>> console=ttyS0,115200n8 debug print-fatal-signals=1
 >> 
 >> This is strange, the problematic patch should use ttynull
 >> only as a fallback. It should not be used when a particular console
 >> is defined on the command line.

 > What happens in my case is console_on_rootfs() doesn't find
 > /dev/console and switching to ttynull. /dev is not present because
 > devtmpfs doesn't automount for initramfs.

But our initramfs/cpio logic ensures that the initramfs has a static
/dev/console device node, so how can that be?

https://git.buildroot.net/buildroot/tree/fs/cpio/cpio.mk#n25

-- 
Bye, Peter Korsgaard