Re: Replacing existing kernel with new on qemuriscv64

[Alistair Francis <alistair23@gmail.com>]

On Mon, Jul 20, 2020 at 11:19 AM Pankaj Vinadrao Joshi
<Pankaj.VJ@exaleapsemi.com> wrote:
>
> Hi Alistair Francis,
>
> Thanks for your response.I have same concern for other riscv hardware with custom kernel will same be applicable for it?If no from where i should change my kernel image since there also i am not able to find grub and the clarification given on web are seems to be very specific to x86 arch where i should look in case of riscv ??

Hello,

I'm not really sure what you are asking.

The way to update the kernel will depend on how you are booting it and
where it is stored. GRUB supports RISC-V, but as there is no UEFI
support in the kernel (yet) it probably isn't the best boot method.
Most hardware will probably use u-boot instead.

Alistair

>
> Thanks
>
> ________________________________
> From: Alistair Francis <alistair23@gmail.com>
> Sent: Monday, July 20, 2020 10:29 PM
> To: Pankaj Vinadrao Joshi <Pankaj.VJ@exaleapsemi.com>
> Cc: qemu-devel@nongnu.org <qemu-devel@nongnu.org>
> Subject: Re: Replacing existing kernel with new on qemuriscv64
>
> On Mon, Jul 20, 2020 at 2:46 AM Pankaj Vinadrao Joshi
> <Pankaj.VJ@exaleapsemi.com> wrote:
> >
> > Hi ,
> > I am trying to replace my existing kernel image which is 5.5.6 to 5.5.7 on qemuriscv64 i would like to mention i have built my qemu image with openembedded-core.
> >
> > i have tried to build the kernel 5.5.7 natively,i was able to build the kernel successfully and in my /boot folder i am able to see vmlinux-5.5.7  but now i want to install this image..i have tried to do it by make install i didnt got any error with it but when i rebooted my system i am getting
> >
> > i have followed the following steps to build kernel
> > $root@qemuriscv64-exaleapsemi-r2:/usr/src/kernel#  make menuconfig arch=riscv64
> > $root@qemuriscv64-exaleapsemi-r2:/usr/src/kernel# make -j4
> > $root@qemuriscv64-exaleapsemi-r2:/usr/src/kernel# make modules_install
> > $root@qemuriscv64-exaleapsemi-r2:/usr/src/kernel# make install
> > sh ./arch/riscv/boot/install.sh 5.5.7 \
> > arch/riscv/boot/Image System.map "/boot"
> > Installing normal kernel
> >
> > $reboot
> > 13024.451157] printk: systemd-shutdow: 37 output lines suppressed due to ratelimiting
> > [13024.527282] systemd-shutdown[1]: Syncing filesystems and block devices.
> > [13024.668538] systemd-shutdown[1]: Sending SIGTERM to remaining processes...
> > [13024.719496] systemd-journald[87]: Received SIGTERM from PID 1 (systemd-shutdow).
> > [13024.769405] systemd-shutdown[1]: Sending SIGKILL to remaining processes...
> > [13024.834318] systemd-shutdown[1]: Unmounting file systems.
> > [13024.868285] [13413]: Remounting '/' read-only in with options '(null)'.
> > [13025.228499] EXT4-fs (vda): re-mounted. Opts: (null)
> > [13025.358123] systemd-shutdown[1]: All filesystems unmounted.
> > [13025.358576] systemd-shutdown[1]: Deactivating swaps.
> > [13025.361264] systemd-shutdown[1]: All swaps deactivated.
> > [13025.361727] systemd-shutdown[1]: Detaching loop devices.
> > [13025.420602] systemd-shutdown[1]: All loop devices detached.
> > [13025.421071] systemd-shutdown[1]: Detaching DM devices.
> > [13025.595237] reboot: Restarting system
> > [13046.599875] rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
> > [13046.600329] (detected by 0, t=5252 jiffies, g=2837145, q=17)
> > [13046.600763] rcu: All QSes seen, last rcu_sched kthread activity 5252 (4298153942-4298148690), jiffies_till_next_fqs=1, root ->qsmask 0x0
> > [13046.601503] systemd-shutdow R  running task        0     1      0 0x00000008
> > [13046.602053] Call Trace:
> > [13046.602562] [<ffffffe00006d3fc>] walk_stackframe+0x0/0xa4
> > [13046.602890] [<ffffffe00006d5e2>] show_stack+0x2a/0x34
> > [13046.603156] [<ffffffe000091094>] sched_show_task+0x158/0x174
> > [13046.603442] [<ffffffe0000c4dde>] rcu_sched_clock_irq+0x6b2/0x6ec
> > [13046.603740] [<ffffffe0000ccadc>] update_process_times+0x1e/0x44
> > [13046.604009] [<ffffffe0000d79dc>] tick_sched_handle.isra.16+0x30/0x3e
> > [13046.604331] [<ffffffe0000d7a38>] tick_sched_timer+0x4e/0x94
> > [13046.604620] [<ffffffe0000cd44a>] __hrtimer_run_queues+0x10c/0x2de
> > [13046.604928] [<ffffffe0000cdc96>] hrtimer_interrupt+0xcc/0x1d6
> > [13046.605236] [<ffffffe0005d3f7c>] riscv_timer_interrupt+0x32/0x3a
> > [13046.605580] [<ffffffe0007889ce>] do_IRQ+0xae/0xba
> > [13046.605837] [<ffffffe00006bd3c>] ret_from_exception+0x0/0xc
> > [13046.606127] [<ffffffe00006ca58>] machine_restart+0xc/0xe
> > [13046.606508] rcu: rcu_sched kthread starved for 5252 jiffies! g2837145 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
> > [13046.606990] rcu: RCU grace-period kthread stack dump:
> > [13046.607257] rcu_sched       R  running task        0    10      2 0x00000000
> > [13046.607610] Call Trace:
> > [13046.607774] [<ffffffe000784258>] __schedule+0x1a8/0x482
> > [13046.608044] [<ffffffe000784592>] schedule+0x60/0xda
> > [13046.608304] [<ffffffe000787a56>] schedule_timeout+0x15c/0x2b2
> > [13046.608602] [<ffffffe0000c2ec8>] rcu_gp_kthread+0x4cc/0x7ec
> > [13046.608889] [<ffffffe00008b0f2>] kthread+0xf0/0x102
> > [13046.609162] [<ffffffe00006bd3c>] ret_from_exception+0x0/0xc
> >
> > ..... so on getting continuously......
> >
> >
> > Can someone help me out how i can replace my kernel to 5.5.7 since i am not able to find grub or grub2 on my riscv platform?? i have googled for the solution but most of them seems to be x86 specific where they are trying to change the grub??Where i should modify for riscv to get my kernel up????
>
> You won't be able to install a new kernel from the QEMU guest. You
> will need to use OpenEmbedded to build a new kernel and boot that.
>
> Alistair
>
> >
> >
> > Thanks
> [EXT]