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

From: Stephen Boyd
Date: Thu Mar 04 2021 - 23:21:24 EST


Quoting Rasmus Villemoes (2021-03-04 15:11:47)
> On 04/03/2021 20.15, Stephen Boyd wrote:
> > 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
>
> Can you avoid claiming a new "top-level" %p modifier? Isn't it better to
> add a new flag to '%pS', say '%pSb' to include build-id?
>

I see that %pSR is used in alpha for the stacktrace. I guess we can have
%pSb and %pSr then.