Re: [PATCH 5/7] printk: Make %pS and friends print module build ID

From: Stephen Boyd
Date: Thu Mar 04 2021 - 14:17:37 EST


Quoting Matthew Wilcox (2021-03-04 09:00:52)
> On Mon, Mar 01, 2021 at 09:47:47AM -0800, Stephen Boyd wrote:
> > Example:
> >
> > WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm] (ed5019fdf5e53be37cb1ba7899292d7e143b259e)
>
> Would the first 12 characters instead of all 40 make it more palatable
> without reducing its utility?

I can't seem to request debuginfo from debuginfod without the full 40
characters. It's not a git sha1 hash.

> And I feel it should be within the [], so maybe this:
>
> WARNING: CPU: 4 PID: 3255 at drivers/misc/lkdtm/bugs.c:83 lkdtm_WARNING+0x28/0x30 [lkdtm ed5019fdf5e5]
>

Sure I could put the hex numbers inside the brackets. I suspect changing
%pS or updating the "Modules linked in:" line isn't going to be
palatable. I've decided to introduce another printk format %pT to print
the stacktrace and then updated the architecture code on arm64 and x86
to see how it goes. Other architecures can be updated if this is
acceptable. I'll send out a patch series in a little bit that also
updates the decode_stacktrace.sh script to parse this.