Today my laptop went to ‘hibernation’ or shut itself down (I not quite sure) during a pacman update, while updating DKMS, of course.
As a result grub can’t find my linux image when I boot it up.
I tried to check a bit in grub’s console mode but I didn’t have had the time to look thoroughly into it yet (work is calling).
But it does sound ugly, right ? 
If you haven’t already, check your bios boot setup to make certain it is pointing to your install correctly.
Boot off a flash drive, connect to a network, mount your partitions to /mnt and /mnt/boot, then arch-chroot /mnt
Once in you can finish updating and do a mkinitcpio, possibly update grub if you use it.
Don’t forget to exit the chroot before rebooting.
thanks Nate
Will try that as soon as I can
update:
tl;dr: that partially did the trick… sadly
I did that finished updating
Then since my /boot folder was ‘empty’ (no kernel or initiramfs img), I reinstalled my kernel image using pacman
I managed to get to my session again, but thing felt a bit broken.
Upon a reboot I had a message telling me that my partition was corrupted. I executed fsck manually as prompted but now I’m stuck on lightdm, keyboard not recognized, and I can’t manage to know what is going wrong. (I tried checking the journal and other logs by going in again booting from usb and mounting my disks)
Feels like I have broken my system and that’ll be easier to reinstall it> Since I’m quite oblivious as what is going wrong here… (I’m glad I have a separate home partition )
This doesn’t “reinstall” the kernel image (just runs mkinitcpio as a side effect,) that’s what mkinitcpio does…
I can’t touch on whether your partitions are an issue or not, that would be something fsck handles, but in cases like yours (reboot during crucial updates) things can vary (though I doubt I wouldn’t be able to make it a fully functional system anymore).
At the end of the day I feel like you’d be better off (knowledge wise) to fix the issues present, at no point is an arch install completely borked, just a matter of work to get it functional again.
mmmh ok. Thanks for the precision (it seemed so looking at pacman logs but I wasn’t quite sure)
I did manage to rebuild a initramfs image, but couldn’t find out how to recreate the kernel image using mkinitcpio 
fsck seems to have done it’s job somewhat correctly, but as I said, a lot of other things seemed quite broken.
If I had more time I might have tried getting my system functional again.
I ended reinstalling it out of frustration (I must say the latest installer is quite nice)
Now I have some config cleanup to do 