On Tue, Nov 24, 2020 at 09:49:16AM +0000, Russell King - ARM Linux admin wrote: > On Tue, Nov 24, 2020 at 10:41:51AM +0200, Ido Schimmel wrote: > > On Tue, Nov 24, 2020 at 01:14:31AM +0100, Andrew Lunn wrote: > > > On Mon, Nov 23, 2020 at 10:06:16PM +0000, Russell King wrote: > > > > Add debugfs support to SFP so that the internal state of the SFP state > > > > machines and hardware signal state can be viewed from userspace, rather > > > > than having to compile a debug kernel to view state state transitions > > > > in the kernel log. The 'state' output looks like: > > > > > > > > Module state: empty > > > > Module probe attempts: 0 0 > > > > Device state: up > > > > Main state: down > > > > Fault recovery remaining retries: 5 > > > > PHY probe remaining retries: 12 > > > > moddef0: 0 > > > > rx_los: 1 > > > > tx_fault: 1 > > > > tx_disable: 1 > > > > > > > > Signed-off-by: Russell King <rmk+ker...@armlinux.org.uk> > > > > > > Hi Russell > > > > > > This looks useful. I always seem to end up recompiling the kernel, > > > which as you said, this should avoid. > > > > FWIW, another option is to use drgn [1]. Especially when the state is > > queried from the kernel and not hardware. We are using that in mlxsw > > [2][3]. > > Presumably that requires /proc/kcore support, which 32-bit ARM doesn't > have.
Yes, it does seem to be required for live debugging. I mostly work with x86 systems, I guess it's completely different for Andrew and you.
